TDKCandidates // Massive renovation + Cocoa legacy mode.

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/CandidateCellData.swift

@@ -1,221 +0,0 @@
-// (c) 2022 and onwards The vChewing Project (MIT-NTL License).
-// ====================
-// This code is released under the MIT license (SPDX-License-Identifier: MIT)
-// ... with NTL restriction stating that:
-// No trademark license is granted to use the trade names, trademarks, service
-// marks, or product names of Contributor, except as required to fulfill notice
-// requirements defined in MIT License.
-
-import Cocoa
-import Shared
-import SwiftUI
-import SwiftUIBackports
-
-// MARK: - Classes used by Candidate Window
-
-/// 用來管理選字窗內顯示的候選字的單位。用 class 型別會比較方便一些。
-public class CandidateCellData: Hashable {
-  public var locale = ""
-  public static var unifiedSize: Double = 16
-  public static var highlightBackground: NSColor = {
-    if #available(macOS 10.14, *) {
-      return .selectedContentBackgroundColor
-    }
-    return NSColor.alternateSelectedControlColor
-  }()
-
-  public var key: String
-  public var displayedText: String
-  public var size: Double { Self.unifiedSize }
-  public var isSelected: Bool = false
-  public var whichRow: Int = 0 // 橫排選字窗專用
-  public var whichColumn: Int = 0 // 縱排選字窗專用
-  public var index: Int = 0
-  public var subIndex: Int = 0
-
-  public var fontSizeCandidate: Double { CandidateCellData.unifiedSize }
-  public var fontSizeKey: Double { max(ceil(CandidateCellData.unifiedSize * 0.6), 11) }
-  public var fontColorKey: NSColor {
-    isSelected ? .selectedMenuItemTextColor.withAlphaComponent(0.8) : .secondaryLabelColor
-  }
-
-  public var fontColorCandidate: NSColor { isSelected ? .selectedMenuItemTextColor : .labelColor }
-
-  public init(key: String, displayedText: String, isSelected: Bool = false) {
-    self.key = key
-    self.displayedText = displayedText
-    self.isSelected = isSelected
-  }
-
-  public static func == (lhs: CandidateCellData, rhs: CandidateCellData) -> Bool {
-    lhs.key == rhs.key && lhs.displayedText == rhs.displayedText
-  }
-
-  public func hash(into hasher: inout Hasher) {
-    hasher.combine(key)
-    hasher.combine(displayedText)
-  }
-
-  public var cellLength: Int {
-    if displayedText.count <= 2 { return Int(ceil(size * 3)) }
-    return Int(ceil(attributedStringForLengthCalculation.boundingDimension.width))
-  }
-
-  public var attributedStringHeader: NSAttributedString {
-    let paraStyleKey = NSMutableParagraphStyle()
-    paraStyleKey.setParagraphStyle(NSParagraphStyle.default)
-    paraStyleKey.alignment = .natural
-    let paraStyle = NSMutableParagraphStyle()
-    paraStyle.setParagraphStyle(NSParagraphStyle.default)
-    paraStyle.alignment = .natural
-    let theFontForCandidateKey: NSFont = {
-      if #available(macOS 10.15, *) {
-        return NSFont.monospacedSystemFont(ofSize: fontSizeKey, weight: .regular)
-      }
-      return NSFont.monospacedDigitSystemFont(ofSize: fontSizeKey, weight: .regular)
-    }()
-    var attrKey: [NSAttributedString.Key: AnyObject] = [
-      .font: theFontForCandidateKey,
-      .paragraphStyle: paraStyleKey,
-    ]
-    if isSelected {
-      attrKey[.foregroundColor] = NSColor.white.withAlphaComponent(0.8)
-    } else {
-      attrKey[.foregroundColor] = NSColor.secondaryLabelColor
-    }
-    let attrStrKey = NSMutableAttributedString(string: key, attributes: attrKey)
-    return attrStrKey
-  }
-
-  public var attributedStringForLengthCalculation: NSAttributedString {
-    let paraStyleKey = NSMutableParagraphStyle()
-    paraStyleKey.setParagraphStyle(NSParagraphStyle.default)
-    paraStyleKey.alignment = .natural
-    let paraStyle = NSMutableParagraphStyle()
-    paraStyle.setParagraphStyle(NSParagraphStyle.default)
-    paraStyle.alignment = .natural
-    paraStyle.lineBreakMode = .byWordWrapping
-    let attrCandidate: [NSAttributedString.Key: AnyObject] = [
-      .font: NSFont.monospacedDigitSystemFont(ofSize: size, weight: .regular),
-      .paragraphStyle: paraStyle,
-    ]
-    let attrStrCandidate = NSMutableAttributedString(string: displayedText + "　", attributes: attrCandidate)
-    return attrStrCandidate
-  }
-
-  public var attributedString: NSAttributedString {
-    let paraStyleKey = NSMutableParagraphStyle()
-    paraStyleKey.setParagraphStyle(NSParagraphStyle.default)
-    paraStyleKey.alignment = .natural
-    let paraStyle = NSMutableParagraphStyle()
-    paraStyle.setParagraphStyle(NSParagraphStyle.default)
-    paraStyle.alignment = .natural
-    paraStyle.lineBreakMode = .byWordWrapping
-    var attrCandidate: [NSAttributedString.Key: AnyObject] = [
-      .font: NSFont.monospacedDigitSystemFont(ofSize: size, weight: .regular),
-      .paragraphStyle: paraStyle,
-    ]
-    if isSelected {
-      attrCandidate[.foregroundColor] = NSColor.white
-    } else {
-      attrCandidate[.foregroundColor] = NSColor.labelColor
-    }
-    if #available(macOS 12, *) {
-      if UserDefaults.standard.bool(forKey: UserDef.kHandleDefaultCandidateFontsByLangIdentifier.rawValue) {
-        attrCandidate[.languageIdentifier] = self.locale as AnyObject
-      }
-    }
-    let attrStrCandidate = NSMutableAttributedString(string: displayedText, attributes: attrCandidate)
-    return attrStrCandidate
-  }
-
-  public var charDescriptions: String {
-    var result = displayedText
-    if displayedText.contains("("), displayedText.count > 2 {
-      result = displayedText.replacingOccurrences(of: "(", with: "").replacingOccurrences(of: ")", with: "")
-    }
-    return result.charDescriptions.joined(separator: "\n")
-  }
-
-  public var minWidthToDrawInSwiftUI: Double {
-    Double(cellLength) + ((displayedText.count > 2) ? 0 : fontSizeKey + 0) + ceil(fontSizeCandidate * 0.4)
-  }
-}
-
-// MARK: - Contents specifically made for macOS 12 and newer.
-
-@available(macOS 12, *)
-public extension CandidateCellData {
-  var attributedStringForSwiftUI: some View {
-    var result: some View {
-      ZStack(alignment: .leading) {
-        if isSelected {
-          Color(nsColor: CandidateCellData.highlightBackground).ignoresSafeArea().cornerRadius(6)
-        }
-        VStack(spacing: 0) {
-          HStack(spacing: 4) {
-            if UserDefaults.standard.bool(forKey: UserDef.kHandleDefaultCandidateFontsByLangIdentifier.rawValue) {
-              Text(AttributedString(attributedStringHeader))
-              Text(AttributedString(attributedString))
-            } else {
-              Text(verbatim: key).font(.system(size: fontSizeKey).monospaced())
-                .foregroundColor(.init(nsColor: fontColorKey)).lineLimit(1)
-              Text(verbatim: displayedText)
-                .font(.init(CTFontCreateUIFontForLanguage(.system, fontSizeCandidate, locale as CFString)!))
-                .foregroundColor(.init(nsColor: fontColorCandidate)).lineLimit(1)
-            }
-          }.padding(3)
-        }.frame(minWidth: minWidthToDrawInSwiftUI, alignment: .leading)
-      }.fixedSize(horizontal: false, vertical: true)
-    }
-    return result
-  }
-}
-
-// MARK: - Contents specifically made for macOS 10.15 and macOS 11.
-
-@available(macOS 10.15, *)
-public extension CandidateCellData {
-  var themeColorBackports: some View {
-    // 設定當前高亮候選字的背景顏色。
-    let result: Color = {
-      switch locale {
-      case "zh-Hans": return Color.red
-      case "zh-Hant": return Color.blue
-      case "ja": return Color.pink
-      default: return Color.accentColor
-      }
-    }()
-    return result.opacity(0.85)
-  }
-
-  var attributedStringForSwiftUIBackports: some View {
-    var result: some View {
-      ZStack(alignment: .leading) {
-        if isSelected {
-          themeColorBackports.cornerRadius(6)
-          VStack(spacing: 0) {
-            HStack(spacing: 4) {
-              Text(verbatim: key).font(.custom("Menlo", size: fontSizeKey))
-                .foregroundColor(Color.white.opacity(0.8)).lineLimit(1)
-              Text(verbatim: displayedText)
-                .font(.init(CTFontCreateUIFontForLanguage(.system, fontSizeCandidate, locale as CFString)!))
-                .foregroundColor(Color(white: 1)).lineLimit(1)
-            }.padding(3).foregroundColor(Color(white: 0.9))
-          }.frame(minWidth: minWidthToDrawInSwiftUI, alignment: .leading)
-        } else {
-          VStack(spacing: 0) {
-            HStack(spacing: 4) {
-              Text(verbatim: key).font(.custom("Menlo", size: fontSizeKey))
-                .foregroundColor(Color.secondary).lineLimit(1)
-              Text(verbatim: displayedText)
-                .font(.init(CTFontCreateUIFontForLanguage(.system, fontSizeCandidate, locale as CFString)!))
-                .foregroundColor(Color.primary).lineLimit(1)
-            }.padding(3).foregroundColor(Color(white: 0.9))
-          }.frame(minWidth: minWidthToDrawInSwiftUI, alignment: .leading)
-        }
-      }.fixedSize(horizontal: false, vertical: true)
-    }
-    return result
-  }
-}

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/CandidateCellData_Core.swift

@@ -0,0 +1,191 @@
+// (c) 2022 and onwards The vChewing Project (MIT-NTL License).
+// ====================
+// This code is released under the MIT license (SPDX-License-Identifier: MIT)
+// ... with NTL restriction stating that:
+// No trademark license is granted to use the trade names, trademarks, service
+// marks, or product names of Contributor, except as required to fulfill notice
+// requirements defined in MIT License.
+
+import Cocoa
+import Shared
+import SwiftUI
+import SwiftUIBackports
+
+// MARK: - Candidate Cell
+
+/// 用來管理選字窗內顯示的候選字的單位。用 class 型別會比較方便一些。
+public class CandidateCellData: Hashable {
+  public var locale = ""
+  public static var unifiedSize: Double = 16
+  public var key: String
+  public var displayedText: String
+  public var size: Double { Self.unifiedSize }
+  public var isHighlighted: Bool = false
+  public var whichLine: Int = 0
+  // 該候選字詞在資料池內的總索引編號
+  public var index: Int = 0
+  // 該候選字詞在當前行/列內的索引編號
+  public var subIndex: Int = 0
+
+  public var charGlyphWidth: Double { ceil(size * 1.0125 + 7) }
+  public var fontSizeCandidate: Double { size }
+  public var fontSizeKey: Double { max(ceil(fontSizeCandidate * 0.6), 11) }
+  public var fontColorKey: NSColor {
+    isHighlighted ? .selectedMenuItemTextColor.withAlphaComponent(0.8) : .secondaryLabelColor
+  }
+
+  public var fontColorCandidate: NSColor { isHighlighted ? .selectedMenuItemTextColor : .labelColor }
+
+  public init(key: String, displayedText: String, isSelected: Bool = false) {
+    self.key = key
+    self.displayedText = displayedText
+    isHighlighted = isSelected
+  }
+
+  public static func == (lhs: CandidateCellData, rhs: CandidateCellData) -> Bool {
+    lhs.key == rhs.key && lhs.displayedText == rhs.displayedText
+  }
+
+  public func hash(into hasher: inout Hasher) {
+    hasher.combine(key)
+    hasher.combine(displayedText)
+  }
+
+  public func cellLength(isMatrix: Bool = true) -> Double {
+    let minLength = ceil(charGlyphWidth * 2 + size)
+    if displayedText.count <= 2, isMatrix { return minLength }
+    return ceil(attributedStringForLengthCalculation.boundingDimension.width)
+  }
+
+  public static let sharedParagraphStyle: NSParagraphStyle = {
+    let paraStyle = NSMutableParagraphStyle()
+    paraStyle.setParagraphStyle(NSParagraphStyle.default)
+    paraStyle.alignment = .natural
+    paraStyle.lineBreakMode = .byWordWrapping
+    return paraStyle
+  }()
+
+  var phraseFont: NSFont {
+    CTFontCreateUIFontForLanguage(.system, size, locale as CFString) ?? NSFont.systemFont(ofSize: size)
+  }
+
+  var highlightedNSColor: NSColor {
+    var result = NSColor.alternateSelectedControlColor
+    var colorBlendAmount: Double = NSApplication.isDarkMode ? 0.3 : 0.0
+    if #available(macOS 10.14, *), !NSApplication.isDarkMode, locale == "zh-Hant" {
+      colorBlendAmount = 0.15
+    }
+    // 設定當前高亮候選字的背景顏色。
+    switch locale {
+    case "zh-Hans":
+      result = NSColor.systemRed
+    case "zh-Hant":
+      result = NSColor.systemBlue
+    case "ja":
+      result = NSColor.systemBrown
+    default: break
+    }
+    var blendingAgainstTarget: NSColor = NSApplication.isDarkMode ? NSColor.black : NSColor.white
+    if #unavailable(macOS 10.14) {
+      colorBlendAmount = 0.3
+      blendingAgainstTarget = NSColor.white
+    }
+    return result.blended(withFraction: colorBlendAmount, of: blendingAgainstTarget)!
+  }
+
+  public var attributedStringForLengthCalculation: NSAttributedString {
+    let attrCandidate: [NSAttributedString.Key: AnyObject] = [
+      .font: NSFont.monospacedDigitSystemFont(ofSize: size, weight: .regular),
+      .paragraphStyle: Self.sharedParagraphStyle,
+    ]
+    let attrStrCandidate = NSAttributedString(string: displayedText + "　", attributes: attrCandidate)
+    return attrStrCandidate
+  }
+
+  public func attributedString(
+    noSpacePadding: Bool = true, withHighlight: Bool = false, isMatrix: Bool = false
+  ) -> NSAttributedString {
+    let attrCandidate: [NSAttributedString.Key: AnyObject] = [
+      .font: NSFont.monospacedDigitSystemFont(ofSize: size, weight: .regular),
+      .paragraphStyle: Self.sharedParagraphStyle,
+    ]
+    let result: NSMutableAttributedString = {
+      if noSpacePadding {
+        let resultNeo = NSMutableAttributedString(string: " ", attributes: attrCandidate)
+        resultNeo.insert(attributedStringPhrase(isMatrix: isMatrix), at: 1)
+        resultNeo.insert(attributedStringHeader, at: 0)
+        return resultNeo
+      }
+      let resultNeo = NSMutableAttributedString(string: "   ", attributes: attrCandidate)
+      resultNeo.insert(attributedStringPhrase(isMatrix: isMatrix), at: 2)
+      resultNeo.insert(attributedStringHeader, at: 1)
+      return resultNeo
+    }()
+    if withHighlight, isHighlighted {
+      result.addAttribute(
+        .backgroundColor, value: highlightedNSColor,
+        range: NSRange(location: 0, length: result.string.utf16.count)
+      )
+    }
+    return result
+  }
+
+  public var attributedStringHeader: NSAttributedString {
+    let theFontForCandidateKey: NSFont = {
+      if #available(macOS 10.15, *) {
+        return NSFont.monospacedSystemFont(ofSize: fontSizeKey, weight: .regular)
+      }
+      return NSFont.monospacedDigitSystemFont(ofSize: fontSizeKey, weight: .regular)
+    }()
+    var attrKey: [NSAttributedString.Key: AnyObject] = [
+      .font: theFontForCandidateKey,
+      .paragraphStyle: Self.sharedParagraphStyle,
+    ]
+    if isHighlighted {
+      attrKey[.foregroundColor] = NSColor.white.withAlphaComponent(0.8)
+    } else {
+      attrKey[.foregroundColor] = NSColor.secondaryLabelColor
+    }
+    let attrStrKey = NSAttributedString(string: key, attributes: attrKey)
+    return attrStrKey
+  }
+
+  public func attributedStringPhrase(isMatrix: Bool = false) -> NSAttributedString {
+    var attrCandidate: [NSAttributedString.Key: AnyObject] = [
+      .font: phraseFont,
+      .paragraphStyle: Self.sharedParagraphStyle,
+    ]
+    if isHighlighted {
+      attrCandidate[.foregroundColor] = NSColor.white
+    } else {
+      attrCandidate[.foregroundColor] = NSColor.labelColor
+    }
+    if #available(macOS 12, *) {
+      if UserDefaults.standard.bool(
+        forKey: UserDef.kLegacyCandidateViewTypesettingMethodEnabled.rawValue
+      ) {
+        attrCandidate[.languageIdentifier] = self.locale as AnyObject
+      }
+    }
+    let delta: String = (isMatrix && displayedText.count < 2) ? "  　" : ""
+    let attrStrCandidate = NSAttributedString(
+      string: displayedText + delta, attributes: attrCandidate
+    )
+    return attrStrCandidate
+  }
+
+  public var charDescriptions: [String] {
+    var result = displayedText
+    if displayedText.contains("("), displayedText.count > 2 {
+      result = displayedText.replacingOccurrences(of: "(", with: "").replacingOccurrences(of: ")", with: "")
+    }
+    return result.flatMap(\.unicodeScalars).compactMap {
+      let theName: String = $0.properties.name ?? ""
+      return String(format: "U+%02X %@", $0.value, theName)
+    }
+  }
+
+  public func minWidthToDraw(isMatrix: Bool = true) -> Double {
+    cellLength(isMatrix: isMatrix) + ceil(fontSizeKey * 0.1)
+  }
+}

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/CandidateCellData_SwiftUIImpl.swift

@@ -0,0 +1,85 @@
+// (c) 2022 and onwards The vChewing Project (MIT-NTL License).
+// ====================
+// This code is released under the MIT license (SPDX-License-Identifier: MIT)
+// ... with NTL restriction stating that:
+// No trademark license is granted to use the trade names, trademarks, service
+// marks, or product names of Contributor, except as required to fulfill notice
+// requirements defined in MIT License.
+
+import Foundation
+import Shared
+import SwiftUI
+
+// MARK: - Contents specifically made for SwiftUI.
+
+@available(macOS 10.15, *)
+public extension CandidateCellData {
+  var themeColor: Color {
+    // 設定當前高亮候選字的背景顏色。
+    let result: Color = {
+      switch locale {
+      case "zh-Hans": return Color.red
+      case "zh-Hant": return Color.blue
+      case "ja": return Color(red: 0.64, green: 0.52, blue: 0.37)
+      default: return Color.accentColor
+      }
+    }()
+    return result.opacity(0.85)
+  }
+
+  var attributedStringForSwiftUIBackports: some View {
+    var result: some View {
+      ZStack(alignment: .leading) {
+        if isHighlighted {
+          themeColor.cornerRadius(6)
+          VStack(spacing: 0) {
+            HStack(spacing: 4) {
+              Text(verbatim: key).font(.custom("Menlo", size: fontSizeKey))
+                .foregroundColor(Color.white.opacity(0.8)).lineLimit(1)
+              Text(verbatim: displayedText)
+                .font(.init(CTFontCreateUIFontForLanguage(.system, fontSizeCandidate, locale as CFString)!))
+                .foregroundColor(Color(white: 1)).lineLimit(1)
+            }.padding(3).foregroundColor(Color(white: 0.9))
+          }.frame(alignment: .leading)
+        } else {
+          VStack(spacing: 0) {
+            HStack(spacing: 4) {
+              Text(verbatim: key).font(.custom("Menlo", size: fontSizeKey))
+                .foregroundColor(Color.secondary).lineLimit(1)
+              Text(verbatim: displayedText)
+                .font(.init(CTFontCreateUIFontForLanguage(.system, fontSizeCandidate, locale as CFString)!))
+                .foregroundColor(Color.primary).lineLimit(1)
+            }.padding(3).foregroundColor(Color(white: 0.9))
+          }.frame(alignment: .leading)
+        }
+      }.fixedSize(horizontal: false, vertical: true)
+    }
+    return result
+  }
+
+  @available(macOS 12, *)
+  var attributedStringForSwiftUI: some View {
+    var result: some View {
+      ZStack(alignment: .leading) {
+        if isHighlighted {
+          themeColor.ignoresSafeArea().cornerRadius(6)
+        }
+        VStack(spacing: 0) {
+          HStack(spacing: 4) {
+            if UserDefaults.standard.bool(forKey: UserDef.kLegacyCandidateViewTypesettingMethodEnabled.rawValue) {
+              Text(AttributedString(attributedStringHeader))
+              Text(AttributedString(attributedStringPhrase()))
+            } else {
+              Text(verbatim: key).font(.system(size: fontSizeKey).monospaced())
+                .foregroundColor(.init(nsColor: fontColorKey)).lineLimit(1)
+              Text(verbatim: displayedText)
+                .font(.init(CTFontCreateUIFontForLanguage(.system, fontSizeCandidate, locale as CFString)!))
+                .foregroundColor(.init(nsColor: fontColorCandidate)).lineLimit(1)
+            }
+          }.padding(3)
+        }.frame(alignment: .leading)
+      }.fixedSize(horizontal: false, vertical: true)
+    }
+    return result
+  }
+}

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/CandidatePool.swift

@@ -6,343 +6,200 @@
 // marks, or product names of Contributor, except as required to fulfill notice
 // requirements defined in MIT License.
 
-import Cocoa
+import Foundation
 import Shared
 
-/// 候選字窗會用到的資料池單位。
+/// 候選字窗會用到的資料池單位，即用即拋。
 public struct CandidatePool {
-  public let blankCell = CandidateCellData(key: " ", displayedText: "　", isSelected: false)
+  public let blankCell: CandidateCellData
-  public var currentLayout: NSUserInterfaceLayoutOrientation = .horizontal
+  public let maxLinesPerPage: Int
-  public private(set) var candidateDataAll: [CandidateCellData] = []
+  public let layout: LayoutOrientation
-  public private(set) var selectionKeys: String
+  public let selectionKeys: String
+  public let candidateDataAll: [CandidateCellData]
+  public var candidateLines: [[CandidateCellData]] = []
+  public var tooltip: String = ""
+  public var reverseLookupResult: [String] = []
   public private(set) var highlightedIndex: Int = 0
+  public private(set) var currentLineNumber = 0
 
-  // 下述變數只有橫排選字窗才會用到
+  private var recordedLineRangeForCurrentPage: Range<Int>?
-  private var currentRowNumber = 0
+  private var previouslyRecordedLineRangeForPreviousPage: Range<Int>?
-  private var maxRowsPerPage = 3
-  private var maxRowCapacity: Int = 6
-  private var candidateRows: [[CandidateCellData]] = []
-
-  // 下述變數只有縱排選字窗才會用到
-  private var currentColumnNumber = 0
-  private var maxColumnsPerPage = 3
-  private var maxColumnCapacity: Int = 6
-  private var candidateColumns: [[CandidateCellData]] = []
 
   // MARK: - 動態變數
 
-  public var maxRowWidth: Int { Int(ceil((Double(maxRowCapacity + 3) * 2 - 0.5) * CandidateCellData.unifiedSize)) }
+  /// 用來在初期化一個候選字詞資料池的時候研判「橫版多行選字窗每行最大應該塞多少個候選字詞」。
-  public var maxWindowWidth: Double {
+  /// 注意：該參數不用來計算視窗寬度，所以無須算上候選字詞間距。
-    Double(maxRowCapacity) * (blankCell.minWidthToDrawInSwiftUI + ceil(CandidateCellData.unifiedSize * 0.5))
+  public var maxRowWidth: Double { ceil(Double(maxLineCapacity) * blankCell.minWidthToDraw()) }
+
+  /// 當前高亮的候選字詞的順序標籤（同時顯示資料池內已有的全部的候選字詞的數量）
+  public var currentPositionLabelText: String {
+    (highlightedIndex + 1).description + "/" + candidateDataAll.count.description
   }
 
-  public var currentLineNumber: Int {
+  /// 當前高亮的候選字詞。
-    switch currentLayout {
+  public var currentCandidate: CandidateCellData? {
-    case .horizontal:
+    (0 ..< candidateDataAll.count).contains(highlightedIndex) ? candidateDataAll[highlightedIndex] : nil
-      return currentRowNumber
-    case .vertical:
-      return currentColumnNumber
-    @unknown default:
-      return 0
-    }
   }
 
-  public var candidateLines: [[CandidateCellData]] {
+  /// 當前高亮的候選字詞的文本。如果相關資料不存在或者不合規的話，則返回空字串。
-    switch currentLayout {
+  public var currentSelectedCandidateText: String? { currentCandidate?.displayedText ?? nil }
-    case .horizontal:
+
-      return candidateRows
+  /// 每行/每列理論上應該最多塞多少個候選字詞。這其實就是當前啟用的選字鍵的數量。
-    case .vertical:
+  public var maxLineCapacity: Int { selectionKeys.count }
-      return candidateColumns
+
-    @unknown default:
+  /// 當選字窗處於單行模式時，如果一行內的內容過少的話，該變數會指出需要再插入多少個空白候選字詞單位。
-      return []
+  public var dummyCellsRequiredForCurrentLine: Int {
-    }
+    maxLineCapacity - candidateLines[currentLineNumber].count
   }
 
-  public var maxLineCapacity: Int {
+  /// 如果當前的行數小於最大行數的話，該變數會指出還需要多少空白行。
-    switch currentLayout {
+  public var lineRangeForFinalPageBlanked: Range<Int> {
-    case .horizontal:
+    0 ..< (maxLinesPerPage - lineRangeForCurrentPage.count)
-      return maxRowCapacity
-    case .vertical:
-      return maxColumnCapacity
-    @unknown default:
-      return 0
-    }
   }
 
-  public var maxLinesPerPage: Int {
+  /// 當前頁所在的行範圍。
-    get {
+  public var lineRangeForCurrentPage: Range<Int> {
-      switch currentLayout {
+    recordedLineRangeForCurrentPage ?? fallbackedLineRangeForCurrentPage
-      case .horizontal:
-        return maxRowsPerPage
-      case .vertical:
-        return maxColumnsPerPage
-      @unknown default:
-        return 0
-      }
-    }
-    set {
-      switch currentLayout {
-      case .horizontal:
-        maxRowsPerPage = newValue
-      case .vertical:
-        maxColumnsPerPage = newValue
-      @unknown default:
-        return
-      }
-    }
   }
 
-  public var rangeForLastPageBlanked: Range<Int> {
+  /// 當前高亮候選字所在的某個相容頁的行範圍。該參數僅用作墊底回退之用途、或者其它極端用途。
-    switch currentLayout {
+  public var fallbackedLineRangeForCurrentPage: Range<Int> {
-    case .horizontal: return rangeForLastHorizontalPageBlanked
+    currentLineNumber ..< min(candidateLines.count, currentLineNumber + maxLinesPerPage)
-    case .vertical: return rangeForLastVerticalPageBlanked
-    @unknown default: return 0 ..< 0
-    }
-  }
-
-  public var rangeForCurrentPage: Range<Int> {
-    switch currentLayout {
-    case .horizontal: return rangeForCurrentHorizontalPage
-    case .vertical: return rangeForCurrentVerticalPage
-    @unknown default: return 0 ..< 0
-    }
   }
 
   // MARK: - Constructors
 
-  /// 初期化一個縱排候選字窗專用資料池。
+  /// 初期化一個候選字窗專用資料池。
   /// - Parameters:
   ///   - candidates: 要塞入的候選字詞陣列。
-  ///   - columnCapacity: (第一縱列的最大候選字詞數量, 陣列畫面展開之後的每一縱列的最大候選字詞數量)。
   ///   - selectionKeys: 選字鍵。
+  ///   - direction: 橫向排列還是縱向排列（預設情況下是縱向）。
   ///   - locale: 區域編碼。例：「zh-Hans」或「zh-Hant」。
   public init(
-    candidates: [String], columnCapacity: Int, columns: Int = 3, selectionKeys: String = "123456789",
+    candidates: [String], lines: Int = 3, selectionKeys: String = "123456789",
-    locale: String = ""
+    layout: LayoutOrientation = .vertical, locale: String = ""
   ) {
-    maxColumnsPerPage = max(1, columns)
+    self.layout = layout
-    maxColumnCapacity = max(1, columnCapacity)
+    maxLinesPerPage = max(1, lines)
-    self.selectionKeys = selectionKeys
+    blankCell = CandidateCellData(key: " ", displayedText: "　", isSelected: false)
-    candidateDataAll = candidates.map { .init(key: "0", displayedText: $0) }
+    blankCell.locale = locale
+    self.selectionKeys = selectionKeys.isEmpty ? "123456789" : selectionKeys
+    var allCandidates = candidates.map { CandidateCellData(key: " ", displayedText: $0) }
+    if allCandidates.isEmpty { allCandidates.append(blankCell) }
+    candidateDataAll = allCandidates
     var currentColumn: [CandidateCellData] = []
     for (i, candidate) in candidateDataAll.enumerated() {
       candidate.index = i
-      candidate.whichColumn = candidateColumns.count
+      candidate.whichLine = candidateLines.count
-      if currentColumn.count == maxColumnCapacity, !currentColumn.isEmpty {
+      var isOverflown: Bool = (currentColumn.count == maxLineCapacity) && !currentColumn.isEmpty
-        candidateColumns.append(currentColumn)
+      if layout == .horizontal {
+        isOverflown = isOverflown
+          || currentColumn.map { $0.cellLength() }.reduce(0, +) >= maxRowWidth - candidate.cellLength()
+      }
+      if isOverflown {
+        candidateLines.append(currentColumn)
         currentColumn.removeAll()
-        candidate.whichColumn += 1
+        candidate.whichLine += 1
       }
       candidate.subIndex = currentColumn.count
       candidate.locale = locale
       currentColumn.append(candidate)
     }
-    candidateColumns.append(currentColumn)
+    candidateLines.append(currentColumn)
-    currentLayout = .vertical
+    recordedLineRangeForCurrentPage = fallbackedLineRangeForCurrentPage
-  }
+    highlight(at: 0)
-
-  /// 初期化一個橫排候選字窗專用資料池。
-  /// - Parameters:
-  ///   - candidates: 要塞入的候選字詞陣列。
-  ///   - rowCapacity: (第一橫行的最大候選字詞數量, 陣列畫面展開之後的每一橫行的最大候選字詞數量)。
-  ///   - selectionKeys: 選字鍵。
-  ///   - locale: 區域編碼。例：「zh-Hans」或「zh-Hant」。
-  public init(
-    candidates: [String], rowCapacity: Int, rows: Int = 3, selectionKeys: String = "123456789", locale: String = ""
-  ) {
-    maxRowsPerPage = max(1, rows)
-    maxRowCapacity = max(1, rowCapacity)
-    self.selectionKeys = selectionKeys
-    candidateDataAll = candidates.map { .init(key: "0", displayedText: $0) }
-    var currentRow: [CandidateCellData] = []
-    for (i, candidate) in candidateDataAll.enumerated() {
-      candidate.index = i
-      candidate.whichRow = candidateRows.count
-      let isOverflown: Bool = currentRow.map(\.cellLength).reduce(0, +) > maxRowWidth
-      if isOverflown || currentRow.count == maxRowCapacity, !currentRow.isEmpty {
-        candidateRows.append(currentRow)
-        currentRow.removeAll()
-        candidate.whichRow += 1
-      }
-      candidate.subIndex = currentRow.count
-      candidate.locale = locale
-      currentRow.append(candidate)
-    }
-    candidateRows.append(currentRow)
-    currentLayout = .horizontal
-  }
-
-  // MARK: Public Functions
-
-  public mutating func selectNewNeighborLine(isForward: Bool) {
-    switch currentLayout {
-    case .horizontal: selectNewNeighborRow(direction: isForward ? .down : .up)
-    case .vertical: selectNewNeighborColumn(direction: isForward ? .right : .left)
-    @unknown default: break
-    }
-  }
-
-  public mutating func highlight(at indexSpecified: Int) {
-    switch currentLayout {
-    case .horizontal: highlightHorizontal(at: indexSpecified)
-    case .vertical: highlightVertical(at: indexSpecified)
-    @unknown default: break
-    }
-    vCLog("\n" + candidateDataAll[highlightedIndex].charDescriptions)
   }
 }
 
-// MARK: - Private Functions
+// MARK: - Public Functions (for all OS)
 
-extension CandidatePool {
+public extension CandidatePool {
-  private enum VerticalDirection {
+  /// 選字窗的候選字詞陳列方向。
-    case up
+  enum LayoutOrientation {
-    case down
+    case horizontal
+    case vertical
   }
 
-  private enum HorizontalDirection {
+  /// 往指定的方向翻頁。
-    case left
+  /// - Parameter isBackward: 是否逆向翻頁。
-    case right
+  /// - Returns: 操作是否順利。
+  @discardableResult mutating func flipPage(isBackward: Bool) -> Bool {
+    backupLineRangeForCurrentPage()
+    defer { flipLineRangeToNeighborPage(isBackward: isBackward) }
+    return consecutivelyFlipLines(isBackward: isBackward, count: maxLinesPerPage)
   }
 
-  private var rangeForLastHorizontalPageBlanked: Range<Int> {
+  /// 嘗試用給定的行內編號推算該候選字在資料池內的總編號。
-    0 ..< (maxRowsPerPage - rangeForCurrentHorizontalPage.count)
+  /// - Parameter subIndex: 給定的行內編號。
+  /// - Returns: 推算結果（可能會是 nil）。
+  func calculateCandidateIndex(subIndex: Int) -> Int? {
+    let arrCurrentLine = candidateLines[currentLineNumber]
+    if !(0 ..< arrCurrentLine.count).contains(subIndex) { return nil }
+    return arrCurrentLine[subIndex].index
   }
 
-  private var rangeForLastVerticalPageBlanked: Range<Int> {
+  /// 往指定的方向連續翻行。
-    0 ..< (maxColumnsPerPage - rangeForCurrentVerticalPage.count)
+  /// - Parameters:
-  }
+  ///   - isBackward: 是否逆向翻行。
-
+  ///   - count: 翻幾行。
-  private var rangeForCurrentHorizontalPage: Range<Int> {
+  /// - Returns: 操作是否順利。
-    currentRowNumber ..< min(candidateRows.count, currentRowNumber + maxRowsPerPage)
+  @discardableResult mutating func consecutivelyFlipLines(isBackward: Bool, count: Int) -> Bool {
-  }
+    switch isBackward {
-
+    case false where currentLineNumber == candidateLines.count - 1:
-  private var rangeForCurrentVerticalPage: Range<Int> {
+      return highlightNeighborCandidate(isBackward: false)
-    currentColumnNumber ..< min(candidateColumns.count, currentColumnNumber + maxColumnsPerPage)
+    case true where currentLineNumber == 0:
-  }
+      return highlightNeighborCandidate(isBackward: true)
-
+    default:
-  private mutating func selectNewNeighborRow(direction: VerticalDirection) {
+      if count <= 0 { return false }
-    let currentSubIndex = candidateDataAll[highlightedIndex].subIndex
+      for _ in 0 ..< min(maxLinesPerPage, count) {
-    var result = currentSubIndex
+        selectNewNeighborLine(isBackward: isBackward)
-    switch direction {
-    case .up:
-      if currentRowNumber <= 0 {
-        if candidateRows.isEmpty { break }
-        let firstRow = candidateRows[0]
-        let newSubIndex = min(currentSubIndex, firstRow.count - 1)
-        highlightHorizontal(at: firstRow[newSubIndex].index)
-        break
       }
-      if currentRowNumber >= candidateRows.count - 1 { currentRowNumber = candidateRows.count - 1 }
+      return true
-      if candidateRows[currentRowNumber].count != candidateRows[currentRowNumber - 1].count {
-        let ratio: Double = min(1, Double(currentSubIndex) / Double(candidateRows[currentRowNumber].count))
-        result = Int(floor(Double(candidateRows[currentRowNumber - 1].count) * ratio))
-      }
-      let targetRow = candidateRows[currentRowNumber - 1]
-      let newSubIndex = min(result, targetRow.count - 1)
-      highlightHorizontal(at: targetRow[newSubIndex].index)
-    case .down:
-      if currentRowNumber >= candidateRows.count - 1 {
-        if candidateRows.isEmpty { break }
-        let finalRow = candidateRows[candidateRows.count - 1]
-        let newSubIndex = min(currentSubIndex, finalRow.count - 1)
-        highlightHorizontal(at: finalRow[newSubIndex].index)
-        break
-      }
-      if candidateRows[currentRowNumber].count != candidateRows[currentRowNumber + 1].count {
-        let ratio: Double = min(1, Double(currentSubIndex) / Double(candidateRows[currentRowNumber].count))
-        result = Int(floor(Double(candidateRows[currentRowNumber + 1].count) * ratio))
-      }
-      let targetRow = candidateRows[currentRowNumber + 1]
-      let newSubIndex = min(result, targetRow.count - 1)
-      highlightHorizontal(at: targetRow[newSubIndex].index)
     }
   }
 
-  private mutating func selectNewNeighborColumn(direction: HorizontalDirection) {
+  /// 嘗試高亮前方或者後方的鄰近候選字詞。
-    let currentSubIndex = candidateDataAll[highlightedIndex].subIndex
+  /// - Parameter isBackward: 是否是後方的鄰近候選字詞。
-    switch direction {
+  /// - Returns: 是否成功。
-    case .left:
+  @discardableResult mutating func highlightNeighborCandidate(isBackward: Bool) -> Bool {
-      if currentColumnNumber <= 0 {
+    switch isBackward {
-        if candidateColumns.isEmpty { break }
+    case false where highlightedIndex >= candidateDataAll.count - 1:
-        let firstColumn = candidateColumns[0]
+      highlight(at: 0)
-        let newSubIndex = min(currentSubIndex, firstColumn.count - 1)
+      return false
-        highlightVertical(at: firstColumn[newSubIndex].index)
+    case true where highlightedIndex <= 0:
-        break
+      highlight(at: candidateDataAll.count - 1)
-      }
+      return false
-      if currentColumnNumber >= candidateColumns.count - 1 { currentColumnNumber = candidateColumns.count - 1 }
+    default:
-      let targetColumn = candidateColumns[currentColumnNumber - 1]
+      highlight(at: highlightedIndex + (isBackward ? -1 : 1))
-      let newSubIndex = min(currentSubIndex, targetColumn.count - 1)
+      return true
-      highlightVertical(at: targetColumn[newSubIndex].index)
-    case .right:
-      if currentColumnNumber >= candidateColumns.count - 1 {
-        if candidateColumns.isEmpty { break }
-        let finalColumn = candidateColumns[candidateColumns.count - 1]
-        let newSubIndex = min(currentSubIndex, finalColumn.count - 1)
-        highlightVertical(at: finalColumn[newSubIndex].index)
-        break
-      }
-      let targetColumn = candidateColumns[currentColumnNumber + 1]
-      let newSubIndex = min(currentSubIndex, targetColumn.count - 1)
-      highlightVertical(at: targetColumn[newSubIndex].index)
     }
   }
 
-  private mutating func highlightHorizontal(at indexSpecified: Int) {
+  /// 高亮指定的候選字。
+  /// - Parameter indexSpecified: 給定的候選字詞索引編號，得是資料池內的總索引編號。
+  mutating func highlight(at indexSpecified: Int) {
     var indexSpecified = indexSpecified
+    let isBackward: Bool = indexSpecified > highlightedIndex
     highlightedIndex = indexSpecified
     if !(0 ..< candidateDataAll.count).contains(highlightedIndex) {
       switch highlightedIndex {
       case candidateDataAll.count...:
-        currentRowNumber = candidateRows.count - 1
+        currentLineNumber = candidateLines.count - 1
         highlightedIndex = max(0, candidateDataAll.count - 1)
         indexSpecified = highlightedIndex
       case ..<0:
         highlightedIndex = 0
-        currentRowNumber = 0
+        currentLineNumber = 0
         indexSpecified = highlightedIndex
       default: break
       }
     }
     for (i, candidate) in candidateDataAll.enumerated() {
-      candidate.isSelected = (indexSpecified == i)
+      candidate.isHighlighted = (indexSpecified == i)
-      if candidate.isSelected { currentRowNumber = candidate.whichRow }
+      if candidate.isHighlighted { currentLineNumber = candidate.whichLine }
     }
-    for (i, candidateRow) in candidateRows.enumerated() {
+    for (i, candidateColumn) in candidateLines.enumerated() {
-      if i != currentRowNumber {
+      if i != currentLineNumber {
-        candidateRow.forEach {
-          $0.key = " "
-        }
-      } else {
-        for (i, neta) in candidateRow.enumerated() {
-          neta.key = selectionKeys.map(\.description)[i]
-        }
-      }
-    }
-  }
-
-  private mutating func highlightVertical(at indexSpecified: Int) {
-    var indexSpecified = indexSpecified
-    highlightedIndex = indexSpecified
-    if !(0 ..< candidateDataAll.count).contains(highlightedIndex) {
-      switch highlightedIndex {
-      case candidateDataAll.count...:
-        currentColumnNumber = candidateColumns.count - 1
-        highlightedIndex = max(0, candidateDataAll.count - 1)
-        indexSpecified = highlightedIndex
-      case ..<0:
-        highlightedIndex = 0
-        currentColumnNumber = 0
-        indexSpecified = highlightedIndex
-      default: break
-      }
-    }
-    for (i, candidate) in candidateDataAll.enumerated() {
-      candidate.isSelected = (indexSpecified == i)
-      if candidate.isSelected { currentColumnNumber = candidate.whichColumn }
-    }
-    for (i, candidateColumn) in candidateColumns.enumerated() {
-      if i != currentColumnNumber {
         candidateColumn.forEach {
           $0.key = " "
         }
@@ -353,5 +210,167 @@ extension CandidatePool {
         }
       }
     }
+    if highlightedIndex != 0, indexSpecified == 0 {
+      recordedLineRangeForCurrentPage = fallbackedLineRangeForCurrentPage
+    } else {
+      fixLineRange(isBackward: isBackward)
+    }
+  }
+}
+
+// MARK: - Private Functions
+
+private extension CandidatePool {
+  enum VerticalDirection {
+    case up
+    case down
+  }
+
+  enum HorizontalDirection {
+    case left
+    case right
+  }
+
+  /// 第一頁所在的行範圍。
+  var lineRangeForFirstPage: Range<Int> {
+    0 ..< min(maxLinesPerPage, candidateLines.count)
+  }
+
+  /// 最後一頁所在的行範圍。
+  var lineRangeForFinalPage: Range<Int> {
+    max(0, candidateLines.count - maxLinesPerPage) ..< candidateLines.count
+  }
+
+  mutating func selectNewNeighborLine(isBackward: Bool) {
+    switch layout {
+    case .horizontal: selectNewNeighborRow(direction: isBackward ? .up : .down)
+    case .vertical: selectNewNeighborColumn(direction: isBackward ? .left : .right)
+    }
+  }
+
+  mutating func fixLineRange(isBackward: Bool = false) {
+    if !lineRangeForCurrentPage.contains(currentLineNumber) {
+      switch isBackward {
+      case false:
+        let theMin = currentLineNumber
+        let theMax = min(theMin + maxLinesPerPage, candidateLines.count)
+        recordedLineRangeForCurrentPage = theMin ..< theMax
+      case true:
+        let theMax = currentLineNumber + 1
+        let theMin = max(0, theMax - maxLinesPerPage)
+        recordedLineRangeForCurrentPage = theMin ..< theMax
+      }
+    }
+  }
+
+  mutating func backupLineRangeForCurrentPage() {
+    previouslyRecordedLineRangeForPreviousPage = lineRangeForCurrentPage
+  }
+
+  mutating func flipLineRangeToNeighborPage(isBackward: Bool = false) {
+    guard let prevRange = previouslyRecordedLineRangeForPreviousPage else { return }
+    var lowerBound = prevRange.lowerBound
+    var upperBound = prevRange.upperBound
+    // 先對上下邊界資料值做模進處理。
+    lowerBound += maxLinesPerPage * (isBackward ? -1 : 1)
+    upperBound += maxLinesPerPage * (isBackward ? -1 : 1)
+    // 然後糾正可能出錯的資料值。
+    branch1: switch isBackward {
+    case false:
+      if upperBound < candidateLines.count { break branch1 }
+      if lowerBound < lineRangeForFinalPage.lowerBound { break branch1 }
+      let isOverFlipped = !lineRangeForFinalPage.contains(currentLineNumber)
+      recordedLineRangeForCurrentPage = isOverFlipped ? lineRangeForFirstPage : lineRangeForFinalPage
+      return
+    case true:
+      if lowerBound > 0 { break branch1 }
+      if upperBound > lineRangeForFirstPage.upperBound { break branch1 }
+      let isOverFlipped = !lineRangeForFirstPage.contains(currentLineNumber)
+      recordedLineRangeForCurrentPage = isOverFlipped ? lineRangeForFinalPage : lineRangeForFirstPage
+      return
+    }
+    let result = lowerBound ..< upperBound
+    if result.contains(currentLineNumber) {
+      recordedLineRangeForCurrentPage = result
+      return
+    }
+    // 應該不會有漏檢的情形了。
+  }
+
+  mutating func selectNewNeighborRow(direction: VerticalDirection) {
+    let currentSubIndex = candidateDataAll[highlightedIndex].subIndex
+    var result = currentSubIndex
+    branch: switch direction {
+    case .up:
+      if currentLineNumber <= 0 {
+        if candidateLines.isEmpty { break }
+        let firstRow = candidateLines[0]
+        let newSubIndex = min(currentSubIndex, firstRow.count - 1)
+        highlight(at: firstRow[newSubIndex].index)
+        fixLineRange(isBackward: false)
+        break branch
+      }
+      if currentLineNumber >= candidateLines.count - 1 { currentLineNumber = candidateLines.count - 1 }
+      result = currentSubIndex
+      // 考慮到選字窗末行往往都是將選字窗貼左排列的（而非左右平鋪排列），所以這裡對「↑」鍵不採用這段特殊處理。
+      // if candidateLines[currentLineNumber].count != candidateLines[currentLineNumber - 1].count {
+      //   let ratio: Double = min(1, Double(currentSubIndex) / Double(candidateLines[currentLineNumber].count))
+      //   result = max(Int(floor(Double(candidateLines[currentLineNumber - 1].count) * ratio)), result)
+      // }
+      let targetRow = candidateLines[currentLineNumber - 1]
+      let newSubIndex = min(result, targetRow.count - 1)
+      highlight(at: targetRow[newSubIndex].index)
+      fixLineRange(isBackward: true)
+    case .down:
+      if currentLineNumber >= candidateLines.count - 1 {
+        if candidateLines.isEmpty { break }
+        let finalRow = candidateLines[candidateLines.count - 1]
+        let newSubIndex = min(currentSubIndex, finalRow.count - 1)
+        highlight(at: finalRow[newSubIndex].index)
+        fixLineRange(isBackward: true)
+        break branch
+      }
+      result = currentSubIndex
+      // 特殊處理。
+      if candidateLines[currentLineNumber].count != candidateLines[currentLineNumber + 1].count {
+        let ratio: Double = min(1, Double(currentSubIndex) / Double(candidateLines[currentLineNumber].count))
+        result = max(Int(floor(Double(candidateLines[currentLineNumber + 1].count) * ratio)), result)
+      }
+      let targetRow = candidateLines[currentLineNumber + 1]
+      let newSubIndex = min(result, targetRow.count - 1)
+      highlight(at: targetRow[newSubIndex].index)
+      fixLineRange(isBackward: false)
+    }
+  }
+
+  mutating func selectNewNeighborColumn(direction: HorizontalDirection) {
+    let currentSubIndex = candidateDataAll[highlightedIndex].subIndex
+    switch direction {
+    case .left:
+      if currentLineNumber <= 0 {
+        if candidateLines.isEmpty { break }
+        let firstColumn = candidateLines[0]
+        let newSubIndex = min(currentSubIndex, firstColumn.count - 1)
+        highlight(at: firstColumn[newSubIndex].index)
+        break
+      }
+      if currentLineNumber >= candidateLines.count - 1 { currentLineNumber = candidateLines.count - 1 }
+      let targetColumn = candidateLines[currentLineNumber - 1]
+      let newSubIndex = min(currentSubIndex, targetColumn.count - 1)
+      highlight(at: targetColumn[newSubIndex].index)
+      fixLineRange(isBackward: true)
+    case .right:
+      if currentLineNumber >= candidateLines.count - 1 {
+        if candidateLines.isEmpty { break }
+        let finalColumn = candidateLines[candidateLines.count - 1]
+        let newSubIndex = min(currentSubIndex, finalColumn.count - 1)
+        highlight(at: finalColumn[newSubIndex].index)
+        break
+      }
+      let targetColumn = candidateLines[currentLineNumber + 1]
+      let newSubIndex = min(currentSubIndex, targetColumn.count - 1)
+      highlight(at: targetColumn[newSubIndex].index)
+      fixLineRange(isBackward: false)
+    }
   }
 }

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/CandidatePool_CocoaImpl.swift

@@ -0,0 +1,171 @@
+// (c) 2022 and onwards The vChewing Project (MIT-NTL License).
+// ====================
+// This code is released under the MIT license (SPDX-License-Identifier: MIT)
+// ... with NTL restriction stating that:
+// No trademark license is granted to use the trade names, trademarks, service
+// marks, or product names of Contributor, except as required to fulfill notice
+// requirements defined in MIT License.
+
+import Cocoa
+
+extension CandidatePool {
+  public var attributedDescription: NSAttributedString {
+    switch layout {
+    case .horizontal: return attributedDescriptionHorizontal
+    case .vertical: return attributedDescriptionVertical
+    }
+  }
+
+  /// 將當前資料池以橫版的形式列印成 NSAttributedString。
+  private var attributedDescriptionHorizontal: NSAttributedString {
+    let paragraphStyle = CandidateCellData.sharedParagraphStyle as! NSMutableParagraphStyle
+    paragraphStyle.lineSpacing = ceil(blankCell.size * 0.3)
+    paragraphStyle.lineBreakStrategy = .pushOut
+    let attrCandidate: [NSAttributedString.Key: AnyObject] = [
+      .font: NSFont.monospacedDigitSystemFont(ofSize: blankCell.size, weight: .regular),
+      .paragraphStyle: paragraphStyle,
+    ]
+    let result = NSMutableAttributedString(string: "", attributes: attrCandidate)
+    let spacer = NSAttributedString(string: " ", attributes: attrCandidate)
+    let lineFeed = NSAttributedString(string: "\n", attributes: attrCandidate)
+    for lineID in lineRangeForCurrentPage {
+      let arrLine = candidateLines[lineID]
+      arrLine.enumerated().forEach { cellID, currentCell in
+        let cellString = NSMutableAttributedString(
+          attributedString: currentCell.attributedString(
+            noSpacePadding: false, withHighlight: true, isMatrix: maxLinesPerPage > 1
+          )
+        )
+        if lineID != currentLineNumber {
+          cellString.addAttribute(
+            .foregroundColor, value: NSColor.controlTextColor,
+            range: .init(location: 0, length: cellString.string.utf16.count)
+          )
+        }
+        result.append(cellString)
+        if cellID < arrLine.count - 1 {
+          result.append(spacer)
+        }
+      }
+      if lineID < lineRangeForCurrentPage.upperBound - 1 || maxLinesPerPage > 1 {
+        result.append(lineFeed)
+      } else {
+        result.append(spacer)
+      }
+    }
+    // 這裡已經換行過了。
+    result.append(attributedDescriptionBottomPanes)
+    return result
+  }
+
+  private var attributedDescriptionVertical: NSAttributedString {
+    let paragraphStyle = CandidateCellData.sharedParagraphStyle as! NSMutableParagraphStyle
+    paragraphStyle.lineSpacing = ceil(blankCell.size * 0.3)
+    paragraphStyle.lineBreakStrategy = .pushOut
+    let attrCandidate: [NSAttributedString.Key: AnyObject] = [
+      .font: NSFont.monospacedDigitSystemFont(ofSize: blankCell.size, weight: .regular),
+      .paragraphStyle: paragraphStyle,
+    ]
+    let result = NSMutableAttributedString(string: "", attributes: attrCandidate)
+    let spacer = NSMutableAttributedString(string: "　", attributes: attrCandidate)
+    let lineFeed = NSAttributedString(string: "\n", attributes: attrCandidate)
+    for (inlineIndex, _) in selectionKeys.enumerated() {
+      for (lineID, lineData) in candidateLines.enumerated() {
+        if !fallbackedLineRangeForCurrentPage.contains(lineID) { continue }
+        if !(0 ..< lineData.count).contains(inlineIndex) { continue }
+        let currentCell = lineData[inlineIndex]
+        let cellString = NSMutableAttributedString(
+          attributedString: currentCell.attributedString(
+            noSpacePadding: false, withHighlight: true, isMatrix: maxLinesPerPage > 1
+          )
+        )
+        if lineID != currentLineNumber {
+          cellString.addAttribute(
+            .foregroundColor, value: NSColor.gray,
+            range: .init(location: 0, length: cellString.string.utf16.count)
+          )
+        }
+        result.append(cellString)
+        if maxLinesPerPage > 1, currentCell.displayedText.count > 1 {
+          if currentCell.isHighlighted {
+            spacer.addAttribute(
+              .backgroundColor,
+              value: currentCell.highlightedNSColor,
+              range: .init(location: 0, length: spacer.string.utf16.count)
+            )
+          } else {
+            spacer.removeAttribute(
+              .backgroundColor,
+              range: .init(location: 0, length: spacer.string.utf16.count)
+            )
+          }
+          result.append(spacer)
+        }
+      }
+      result.append(lineFeed)
+    }
+    // 這裡已經換行過了。
+    result.append(attributedDescriptionBottomPanes)
+    return result
+  }
+
+  private var attributedDescriptionBottomPanes: NSAttributedString {
+    let paragraphStyle = CandidateCellData.sharedParagraphStyle as! NSMutableParagraphStyle
+    paragraphStyle.lineSpacing = ceil(blankCell.size * 0.3)
+    paragraphStyle.lineBreakStrategy = .pushOut
+    let attrCandidate: [NSAttributedString.Key: AnyObject] = [
+      .font: NSFont.monospacedDigitSystemFont(ofSize: blankCell.size, weight: .regular),
+      .paragraphStyle: paragraphStyle,
+    ]
+    let result = NSMutableAttributedString(string: "", attributes: attrCandidate)
+    let positionCounterColorBG = NSApplication.isDarkMode
+      ? NSColor(white: 0.215, alpha: 0.7)
+      : NSColor(white: 0.9, alpha: 0.7)
+    let positionCounterColorText = NSColor.controlTextColor
+    let positionCounterTextSize = max(ceil(CandidateCellData.unifiedSize * 0.7), 11)
+    let attrPositionCounter: [NSAttributedString.Key: AnyObject] = [
+      .font: NSFont.monospacedDigitSystemFont(ofSize: positionCounterTextSize, weight: .bold),
+      .paragraphStyle: paragraphStyle,
+      .backgroundColor: positionCounterColorBG,
+      .foregroundColor: positionCounterColorText,
+    ]
+    let positionCounter = NSAttributedString(
+      string: " \(currentPositionLabelText) ", attributes: attrPositionCounter
+    )
+    result.append(positionCounter)
+
+    if !tooltip.isEmpty {
+      let attrTooltip: [NSAttributedString.Key: AnyObject] = [
+        .font: NSFont.monospacedDigitSystemFont(ofSize: positionCounterTextSize, weight: .regular),
+        .paragraphStyle: paragraphStyle,
+      ]
+      let tooltipText = NSAttributedString(
+        string: " \(tooltip) ", attributes: attrTooltip
+      )
+      result.append(tooltipText)
+    }
+
+    if !reverseLookupResult.isEmpty {
+      let reverseLookupTextSize = max(ceil(CandidateCellData.unifiedSize * 0.6), 9)
+      let reverseLookupColorBG = NSApplication.isDarkMode
+        ? NSColor(white: 0.1, alpha: 1)
+        : NSColor(white: 0.9, alpha: 1)
+      let attrReverseLookup: [NSAttributedString.Key: AnyObject] = [
+        .font: NSFont.monospacedDigitSystemFont(ofSize: reverseLookupTextSize, weight: .regular),
+        .paragraphStyle: paragraphStyle,
+        .backgroundColor: reverseLookupColorBG,
+      ]
+      let attrReverseLookupSpacer: [NSAttributedString.Key: AnyObject] = [
+        .font: NSFont.monospacedDigitSystemFont(ofSize: reverseLookupTextSize, weight: .regular),
+        .paragraphStyle: paragraphStyle,
+      ]
+      for neta in reverseLookupResult {
+        result.append(NSAttributedString(string: " ", attributes: attrReverseLookupSpacer))
+        result.append(NSAttributedString(string: " \(neta) ", attributes: attrReverseLookup))
+        if maxLinesPerPage == 1 { break }
+      }
+    }
+    result.addAttribute(.paragraphStyle, value: paragraphStyle, range: .init(location: 0, length: result.string.utf16.count))
+    return result
+  }
+}

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/TDKCandidates/CtlCandidateTDK.swift

@@ -9,61 +9,44 @@
 import Cocoa
 import CocoaExtension
 import Shared
+import SwiftExtension
 import SwiftUI
 
-@available(macOS 10.15, *)
+private extension NSUserInterfaceLayoutOrientation {
+  var layoutTDK: CandidatePool.LayoutOrientation {
+    switch self {
+    case .horizontal:
+      return .horizontal
+    case .vertical:
+      return .vertical
+    @unknown default:
+      return .horizontal
+    }
+  }
+}
+
 public class CtlCandidateTDK: CtlCandidate {
   public var maxLinesPerPage: Int = 0
-
+  public var isLegacyMode: Bool = false
-  private static var thePoolHorizontal: CandidatePool = .init(candidates: [], rowCapacity: 6)
+  private static var thePool: CandidatePool = .init(candidates: [])
-  private static var thePoolVertical: CandidatePool = .init(candidates: [], columnCapacity: 6)
   private static var currentView: NSView = .init()
 
-  @available(macOS 12, *)
+  @available(macOS 10.15, *)
-  private var theViewHorizontal: some View {
+  private var theView: some View {
-    VwrCandidateHorizontal(
+    VwrCandidateTDK(
-      controller: self, thePool: Self.thePoolHorizontal,
+      controller: self, thePool: Self.thePool
-      tooltip: tooltip, reverseLookupResult: reverseLookupResult
     ).edgesIgnoringSafeArea(.top)
   }
 
-  @available(macOS 12, *)
+  private var theViewLegacy: NSView {
-  private var theViewVertical: some View {
+    let textField = NSTextField(
-    VwrCandidateVertical(
+      labelWithAttributedString: Self.thePool.attributedDescription
-      controller: self, thePool: Self.thePoolVertical,
+    )
-      tooltip: tooltip, reverseLookupResult: reverseLookupResult
+    textField.isSelectable = false
-    ).edgesIgnoringSafeArea(.top)
+    textField.allowsEditingTextAttributes = false
-  }
+    textField.preferredMaxLayoutWidth = textField.frame.width
-
+    textField.backgroundColor = .controlBackgroundColor
-  private var theViewHorizontalBackports: some View {
+    return textField
-    VwrCandidateHorizontalBackports(
-      controller: self, thePool: Self.thePoolHorizontal,
-      tooltip: tooltip, reverseLookupResult: reverseLookupResult
-    ).edgesIgnoringSafeArea(.top)
-  }
-
-  private var theViewVerticalBackports: some View {
-    VwrCandidateVerticalBackports(
-      controller: self, thePool: Self.thePoolVertical,
-      tooltip: tooltip, reverseLookupResult: reverseLookupResult
-    ).edgesIgnoringSafeArea(.top)
-  }
-
-  private var thePool: CandidatePool {
-    get {
-      switch currentLayout {
-      case .horizontal: return Self.thePoolHorizontal
-      case .vertical: return Self.thePoolVertical
-      @unknown default: return .init(candidates: [], rowCapacity: 0)
-      }
-    }
-    set {
-      switch currentLayout {
-      case .horizontal: Self.thePoolHorizontal = newValue
-      case .vertical: Self.thePoolVertical = newValue
-      @unknown default: break
-      }
-    }
   }
 
   // MARK: - Constructors
@@ -93,165 +76,108 @@ public class CtlCandidateTDK: CtlCandidate {
   // MARK: - Public functions
 
   override public func reloadData() {
-    CandidateCellData.highlightBackground = highlightedColor()
     CandidateCellData.unifiedSize = candidateFont.pointSize
     guard let delegate = delegate else { return }
-
+    Self.thePool = .init(
-    switch currentLayout {
+      candidates: delegate.candidatePairs(conv: true).map(\.1), lines: maxLinesPerPage,
-    case .horizontal:
+      selectionKeys: delegate.selectionKeys, layout: currentLayout.layoutTDK, locale: locale
-      Self.thePoolHorizontal = .init(
+    )
-        candidates: delegate.candidatePairs(conv: true).map(\.1), rowCapacity: 6,
+    Self.thePool.tooltip = tooltip
-        rows: maxLinesPerPage, selectionKeys: delegate.selectionKeys, locale: locale
+    Self.thePool.reverseLookupResult = reverseLookupResult
-      )
+    Self.thePool.highlight(at: 0)
-      Self.thePoolHorizontal.highlight(at: 0)
-    case .vertical:
-      Self.thePoolVertical = .init(
-        candidates: delegate.candidatePairs(conv: true).map(\.1), columnCapacity: 6,
-        columns: maxLinesPerPage, selectionKeys: delegate.selectionKeys, locale: locale
-      )
-      Self.thePoolVertical.highlight(at: 0)
-    @unknown default:
-      return
-    }
     updateDisplay()
   }
 
   override open func updateDisplay() {
     guard let window = window else { return }
-    reverseLookupResult = delegate?.reverseLookup(for: currentSelectedCandidateText) ?? []
+    if let currentCandidateText = Self.thePool.currentSelectedCandidateText {
-    switch currentLayout {
+      reverseLookupResult = delegate?.reverseLookup(for: currentCandidateText) ?? []
-    case .horizontal:
+      Self.thePool.reverseLookupResult = reverseLookupResult
-      DispatchQueue.main.async { [self] in
+    }
-        if #available(macOS 12, *) {
+    DispatchQueue.main.async { [self] in
-          Self.currentView = NSHostingView(rootView: theViewHorizontal)
+      if #available(macOS 10.15, *) {
-        } else {
+        if isLegacyMode {
-          Self.currentView = NSHostingView(rootView: theViewHorizontalBackports)
+          updateNSWindowLegacy(window)
+          return
         }
+        window.isOpaque = false
+        window.backgroundColor = NSColor.clear
+        Self.currentView = NSHostingView(rootView: theView)
         let newSize = Self.currentView.fittingSize
         window.contentView = Self.currentView
         window.setContentSize(newSize)
+      } else {
+        updateNSWindowLegacy(window)
       }
-    case .vertical:
-      DispatchQueue.main.async { [self] in
-        if #available(macOS 12, *) {
-          Self.currentView = NSHostingView(rootView: theViewVertical)
-        } else {
-          Self.currentView = NSHostingView(rootView: theViewVerticalBackports)
-        }
-        let newSize = Self.currentView.fittingSize
-        window.contentView = Self.currentView
-        window.setContentSize(newSize)
-      }
-    @unknown default:
-      return
     }
   }
 
+  func updateNSWindowLegacy(_ window: NSWindow) {
+    window.isOpaque = true
+    window.backgroundColor = NSColor.controlBackgroundColor
+    let viewToDraw = theViewLegacy
+    let coreSize = viewToDraw.fittingSize
+    let padding: Double = 5
+    let outerSize: NSSize = .init(
+      width: coreSize.width + 2 * padding,
+      height: coreSize.height + 2 * padding
+    )
+    let innerOrigin: NSPoint = .init(x: padding, y: padding)
+    let outerRect: NSRect = .init(origin: .zero, size: outerSize)
+    viewToDraw.setFrameOrigin(innerOrigin)
+    Self.currentView = NSView(frame: outerRect)
+    Self.currentView.addSubview(viewToDraw)
+    window.contentView = Self.currentView
+    window.setContentSize(outerSize)
+  }
+
+  // Already implemented in CandidatePool.
   @discardableResult override public func showNextPage() -> Bool {
-    showNextLine(count: thePool.maxLinesPerPage)
+    defer { updateDisplay() }
-  }
+    return Self.thePool.flipPage(isBackward: false)
-
-  @discardableResult override public func showNextLine() -> Bool {
-    showNextLine(count: 1)
-  }
-
-  public func showNextLine(count: Int) -> Bool {
-    if thePool.currentLineNumber == thePool.candidateLines.count - 1 {
-      return highlightNextCandidate()
-    }
-    if count <= 0 { return false }
-    for _ in 0 ..< min(thePool.maxLinesPerPage, count) {
-      thePool.selectNewNeighborLine(isForward: true)
-    }
-    updateDisplay()
-    return true
   }
 
+  // Already implemented in CandidatePool.
   @discardableResult override public func showPreviousPage() -> Bool {
-    showPreviousLine(count: thePool.maxLinesPerPage)
+    defer { updateDisplay() }
+    return Self.thePool.flipPage(isBackward: true)
   }
 
+  // Already implemented in CandidatePool.
   @discardableResult override public func showPreviousLine() -> Bool {
-    showPreviousLine(count: 1)
+    defer { updateDisplay() }
+    return Self.thePool.consecutivelyFlipLines(isBackward: true, count: 1)
   }
 
-  public func showPreviousLine(count: Int) -> Bool {
+  // Already implemented in CandidatePool.
-    if thePool.currentLineNumber == 0 {
+  @discardableResult override public func showNextLine() -> Bool {
-      return highlightPreviousCandidate()
+    defer { updateDisplay() }
-    }
+    return Self.thePool.consecutivelyFlipLines(isBackward: false, count: 1)
-    if count <= 0 { return false }
-    for _ in 0 ..< min(thePool.maxLinesPerPage, count) {
-      thePool.selectNewNeighborLine(isForward: false)
-    }
-    updateDisplay()
-    return true
   }
 
+  // Already implemented in CandidatePool.
   @discardableResult override public func highlightNextCandidate() -> Bool {
-    if thePool.highlightedIndex == thePool.candidateDataAll.count - 1 {
+    defer { updateDisplay() }
-      thePool.highlight(at: 0)
+    return Self.thePool.highlightNeighborCandidate(isBackward: false)
-      updateDisplay()
-      return false
-    }
-    thePool.highlight(at: thePool.highlightedIndex + 1)
-    updateDisplay()
-    return true
   }
 
+  // Already implemented in CandidatePool.
   @discardableResult override public func highlightPreviousCandidate() -> Bool {
-    if thePool.highlightedIndex == 0 {
+    defer { updateDisplay() }
-      thePool.highlight(at: thePool.candidateDataAll.count - 1)
+    return Self.thePool.highlightNeighborCandidate(isBackward: true)
-      updateDisplay()
-      return false
-    }
-    thePool.highlight(at: thePool.highlightedIndex - 1)
-    updateDisplay()
-    return true
   }
 
-  override public func candidateIndexAtKeyLabelIndex(_ id: Int) -> Int {
+  // Already implemented in CandidatePool.
-    let arrCurrentLine = thePool.candidateLines[thePool.currentLineNumber]
+  override public func candidateIndexAtKeyLabelIndex(_ id: Int) -> Int? {
-    if !(0 ..< arrCurrentLine.count).contains(id) { return -114_514 }
+    Self.thePool.calculateCandidateIndex(subIndex: id)
-    let actualID = max(0, min(id, arrCurrentLine.count - 1))
-    return arrCurrentLine[actualID].index
   }
 
+  // Already implemented in CandidatePool.
   override public var highlightedIndex: Int {
-    get { thePool.highlightedIndex }
+    get { Self.thePool.highlightedIndex }
     set {
-      thePool.highlight(at: newValue)
+      Self.thePool.highlight(at: newValue)
       updateDisplay()
     }
   }
 }
-
-@available(macOS 10.15, *)
-extension CtlCandidateTDK {
-  private var isMontereyAvailable: Bool {
-    if #unavailable(macOS 12) { return false }
-    return true
-  }
-
-  private var currentSelectedCandidateText: String {
-    if thePool.candidateDataAll.count > highlightedIndex {
-      return thePool.candidateDataAll[highlightedIndex].displayedText
-    }
-    return ""
-  }
-}
-
-@available(macOS 10.15, *)
-public extension CtlCandidateTDK {
-  var highlightedColorUIBackports: some View {
-    // 設定當前高亮候選字的背景顏色。
-    let result: Color = {
-      switch locale {
-      case "zh-Hans": return Color.red
-      case "zh-Hant": return Color.blue
-      case "ja": return Color.pink
-      default: return Color.accentColor
-      }
-    }()
-    return result.opacity(0.85)
-  }
-}

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/TDKCandidates/VwrCandidateTDK.swift

@@ -0,0 +1,508 @@
+// (c) 2022 and onwards The vChewing Project (MIT-NTL License).
+// ====================
+// This code is released under the MIT license (SPDX-License-Identifier: MIT)
+// ... with NTL restriction stating that:
+// No trademark license is granted to use the trade names, trademarks, service
+// marks, or product names of Contributor, except as required to fulfill notice
+// requirements defined in MIT License.
+
+import Cocoa
+import Shared
+import SwiftUI
+import SwiftUIBackports
+
+// MARK: - Main View
+
+@available(macOS 10.15, *)
+public struct VwrCandidateTDK: View {
+  public weak var controller: CtlCandidateTDK?
+  @Environment(\.colorScheme) var colorScheme
+  @State public var thePool: CandidatePool
+  @State public var forceCatalinaCompatibility: Bool = false
+  var tooltip: String { thePool.tooltip }
+  var reverseLookupResult: [String] { thePool.reverseLookupResult }
+
+  let horizontalCellSpacing: CGFloat = 0
+
+  public var body: some View {
+    Group {
+      VStack(alignment: .leading, spacing: 0) {
+        switch thePool.layout {
+        case .horizontal:
+          ZStack {
+            candidateListBackground
+            HStack {
+              mainViewHorizontal
+              if thePool.maxLinesPerPage == 1 {
+                rightPanes
+              }
+            }
+          }
+        default:
+          mainViewVertical.background(candidateListBackground)
+        }
+        if thePool.maxLinesPerPage > 1 || thePool.layout == .vertical {
+          if controller?.delegate?.showReverseLookupResult ?? true, !tooltip.isEmpty {
+            ZStack(alignment: .leading) {
+              bottomPanelBackgroundTDK
+                .opacity(colorScheme == .dark ? 0 : 0.35)
+              reverseLookupPane.padding([.top, .horizontal], 4).padding([.bottom], 2)
+            }
+          }
+          statusBar.background(
+            bottomPanelBackgroundTDK
+              .opacity(colorScheme == .dark ? 0.35 : 0.5)
+          )
+        }
+      }
+      .frame(minWidth: windowWidth, maxWidth: windowWidth)
+      .background(candidateListBackground)
+      .overlay(
+        RoundedRectangle(cornerRadius: 10).stroke(
+          absoluteBackgroundColor.opacity(colorScheme == .dark ? 1 : 0.1), lineWidth: 0.5
+        )
+      )
+      .cornerRadius(10)
+    }
+  }
+}
+
+// MARK: - Main Views.
+
+@available(macOS 10.15, *)
+extension VwrCandidateTDK {
+  var mainViewHorizontal: some View {
+    ScrollView(.vertical, showsIndicators: false) {
+      VStack(alignment: .leading, spacing: 1.6) {
+        ForEach(thePool.lineRangeForCurrentPage, id: \.self) { rowIndex in
+          ZStack(alignment: .leading) {
+            lineBackground(lineID: rowIndex).cornerRadius(6)
+            HStack(spacing: horizontalCellSpacing) {
+              ForEach(Array(thePool.candidateLines[rowIndex]), id: \.self) { currentCandidate in
+                drawCandidate(currentCandidate).fixedSize()
+              }
+            }
+          }
+          .opacity(rowIndex == thePool.currentLineNumber ? 1 : 0.95)
+          .id(rowIndex)
+        }
+        if thePool.maxLinesPerPage - thePool.lineRangeForCurrentPage.count > 0 {
+          ForEach(thePool.lineRangeForFinalPageBlanked, id: \.self) { _ in
+            HStack(spacing: 0) {
+              attributedStringFor(cell: thePool.blankCell)
+                .frame(alignment: .topLeading)
+                .contentShape(Rectangle())
+              Spacer()
+            }.frame(
+              minWidth: 0,
+              maxWidth: thePool.maxLinesPerPage != 1 ? .infinity : nil,
+              alignment: .topLeading
+            )
+          }
+        }
+      }
+    }
+    .fixedSize(horizontal: thePool.maxLinesPerPage == 1, vertical: true)
+    .padding([.horizontal, .top], 5)
+    .padding([.bottom], thePool.maxLinesPerPage == 1 ? 5 : 2)
+  }
+
+  var mainViewVertical: some View {
+    ScrollView(.horizontal, showsIndicators: false) {
+      HStack(alignment: .top, spacing: 4) {
+        ForEach(Array(thePool.lineRangeForCurrentPage.enumerated()), id: \.offset) { loopIndex, columnIndex in
+          VStack(alignment: .leading, spacing: 0) {
+            ForEach(Array(thePool.candidateLines[columnIndex]), id: \.self) { currentCandidate in
+              drawCandidate(currentCandidate)
+            }
+            if thePool.candidateLines[columnIndex].count < thePool.maxLineCapacity {
+              ForEach(0 ..< thePool.dummyCellsRequiredForCurrentLine, id: \.self) { _ in
+                drawCandidate(thePool.blankCell)
+              }
+            }
+          }
+          .background(lineBackground(lineID: columnIndex)).cornerRadius(6)
+          .opacity(columnIndex == thePool.currentLineNumber ? 1 : 0.95)
+          .frame(
+            minWidth: thePool.maxLinesPerPage == 1
+              ? max(Double(CandidateCellData.unifiedSize * 6), 90)
+              : nil,
+            alignment: .topLeading
+          )
+          .id(columnIndex)
+          if thePool.maxLinesPerPage > 1, thePool.maxLinesPerPage <= loopIndex + 1 {
+            Spacer(minLength: 0)
+          }
+        }
+        if thePool.maxLinesPerPage - thePool.lineRangeForCurrentPage.count > 0 {
+          ForEach(Array(thePool.lineRangeForFinalPageBlanked.enumerated()), id: \.offset) { loopIndex, _ in
+            VStack(alignment: .leading, spacing: 0) {
+              ForEach(0 ..< thePool.maxLineCapacity, id: \.self) { _ in
+                attributedStringFor(cell: thePool.blankCell).fixedSize()
+                  .frame(
+                    width: ceil(thePool.blankCell.minWidthToDraw(isMatrix: true)),
+                    alignment: .topLeading
+                  )
+                  .contentShape(Rectangle())
+              }
+            }.frame(
+              minWidth: 0,
+              maxWidth: .infinity,
+              alignment: .topLeading
+            )
+            if thePool.maxLinesPerPage > 1,
+               loopIndex >= thePool.maxLinesPerPage - thePool.lineRangeForCurrentPage.count - 1
+            {
+              Spacer(minLength: 0)
+            }
+          }
+        }
+      }
+    }
+    .fixedSize(horizontal: true, vertical: false)
+    .padding([.horizontal, .top], 5)
+    .padding([.bottom], thePool.maxLinesPerPage == 1 ? 5 : 2)
+  }
+}
+
+// MARK: - Common Components.
+
+@available(macOS 10.15, *)
+extension VwrCandidateTDK {
+  func drawCandidate(_ cell: CandidateCellData) -> some View {
+    attributedStringFor(cell: cell)
+      .frame(minWidth: cellWidth(cell).min, maxWidth: cellWidth(cell).max, alignment: .topLeading)
+      .contentShape(Rectangle())
+      .onTapGesture { didSelectCandidateAt(cell.index) }
+      .contextMenu {
+        if controller?.delegate?.isCandidateContextMenuEnabled ?? false {
+          Button {
+            didRightClickCandidateAt(cell.index, action: .toBoost)
+          } label: {
+            Text("↑ " + cell.displayedText)
+          }
+          Button {
+            didRightClickCandidateAt(cell.index, action: .toNerf)
+          } label: {
+            Text("↓ " + cell.displayedText)
+          }
+          Button {
+            didRightClickCandidateAt(cell.index, action: .toFilter)
+          } label: {
+            Text("✖︎ " + cell.displayedText)
+          }
+        }
+      }
+  }
+
+  func lineBackground(lineID: Int) -> Color {
+    let isCurrentLineInMatrix = lineID == thePool.currentLineNumber && thePool.maxLinesPerPage != 1
+    switch thePool.layout {
+    case .horizontal where isCurrentLineInMatrix:
+      return Color.primary.opacity(0.05)
+    case .vertical where isCurrentLineInMatrix:
+      return absoluteBackgroundColor.opacity(0.15)
+    default:
+      return Color.clear
+    }
+  }
+
+  func cellWidth(_ cell: CandidateCellData) -> (min: CGFloat?, max: CGFloat?) {
+    let minAccepted = ceil(thePool.blankCell.minWidthToDraw(isMatrix: false) * 1.1)
+    let defaultMin: CGFloat = cell.minWidthToDraw(isMatrix: thePool.maxLinesPerPage != 1)
+    var min: CGFloat = defaultMin
+    if thePool.layout != .vertical, thePool.maxLinesPerPage == 1 {
+      min = max(minAccepted, cell.minWidthToDraw(isMatrix: false))
+    }
+    return (min, nil)
+  }
+
+  var windowWidth: CGFloat? {
+    let paddings: CGFloat = 10.0
+    let spacings: CGFloat = horizontalCellSpacing * Double(thePool.maxLineCapacity - 1)
+    let maxWindowWith: CGFloat
+      = ceil(
+        Double(thePool.maxLineCapacity) * (thePool.blankCell.minWidthToDraw())
+          + paddings + spacings
+      )
+    return thePool.layout == .horizontal && thePool.maxLinesPerPage > 1 ? maxWindowWith : nil
+  }
+
+  var firstReverseLookupResult: String {
+    reverseLookupResult.first?.trimmingCharacters(in: .newlines) ?? ""
+  }
+
+  /// 以系統字型就給定的粗細狀態與字號來測量給定的字串的渲染寬度，且給出其「向上取整值」。
+  /// - Remark: 所有 SwiftUI Text 元件必須手動在介面元素尺寸處理這方面加上向上取整的步驟，
+  /// 否則的話：當元素尺寸不是整數、且整個視窗內部的 View 都在 .fixedSize() 的時候，
+  /// 視窗內整個 View 的橫向或縱向起始座標可能就不是 0 而是 -0.5。
+  /// - Parameters:
+  ///   - text: 給定的字串。
+  ///   - fontSize: 給定的字號。
+  ///   - isBold: 給定的粗細狀態。
+  /// - Returns: 測量出來的字串渲染寬度，經過向上取整之處理。
+  func getTextWidth(text: String, fontSize: CGFloat, isBold: Bool) -> CGFloat? {
+    guard !text.isEmpty else { return nil }
+    let attributes: [NSAttributedString.Key: AnyObject] = [
+      .font: NSFont.systemFont(ofSize: fontSize, weight: isBold ? .bold : .regular),
+      .paragraphStyle: CandidateCellData.sharedParagraphStyle,
+    ]
+    let attrString = NSAttributedString(string: text, attributes: attributes)
+    return ceil(attrString.boundingDimension.width)
+  }
+
+  var positionLabelView: some View {
+    ZStack {
+      Color(white: colorScheme == .dark ? 0.215 : 0.9).cornerRadius(4)
+      Text(thePool.currentPositionLabelText).lineLimit(1)
+        .font(.system(size: max(ceil(CandidateCellData.unifiedSize * 0.7), 11), weight: .bold))
+        .frame(
+          width: getTextWidth(
+            text: thePool.currentPositionLabelText,
+            fontSize: max(ceil(CandidateCellData.unifiedSize * 0.7), 11),
+            isBold: true
+          )
+        )
+        .padding([.horizontal], 2)
+        .foregroundColor(.primary.opacity(0.8))
+    }.fixedSize()
+  }
+
+  var rightPanes: some View {
+    HStack {
+      if !tooltip.isEmpty {
+        ZStack(alignment: .center) {
+          Circle().fill(highlightBackgroundTDK.opacity(0.8))
+          Text(tooltip.first?.description ?? "").padding(2).font(.system(size: CandidateCellData.unifiedSize))
+        }.frame(width: ceil(CandidateCellData.unifiedSize * 1.7), height: ceil(CandidateCellData.unifiedSize * 1.7))
+      }
+      VStack(alignment: .center, spacing: 1) {
+        positionLabelView
+        if controller?.delegate?.showReverseLookupResult ?? true {
+          if !firstReverseLookupResult.isEmpty {
+            ZStack(alignment: .center) {
+              Color(white: colorScheme == .dark ? 0.2 : 0.9).cornerRadius(4)
+              Text(firstReverseLookupResult)
+                .font(.system(size: max(ceil(CandidateCellData.unifiedSize * 0.6), 9)))
+                .frame(
+                  width: getTextWidth(
+                    text: firstReverseLookupResult,
+                    fontSize: max(ceil(CandidateCellData.unifiedSize * 0.6), 9),
+                    isBold: false
+                  )
+                )
+                .opacity(0.8).padding([.horizontal], 4)
+            }.fixedSize()
+          }
+        }
+      }
+      .opacity(0.9)
+      .fixedSize()
+      .padding([.trailing], 12)
+    }
+  }
+
+  var reverseLookupPane: some View {
+    HStack(alignment: .center, spacing: 2) {
+      if thePool.maxLinesPerPage == 1 {
+        if !firstReverseLookupResult.isEmpty {
+          ZStack(alignment: .center) {
+            Color(white: colorScheme == .dark ? 0.3 : 0.9).cornerRadius(3)
+            Text("\(firstReverseLookupResult.trimmingCharacters(in: .newlines))")
+              .lineLimit(1).padding([.horizontal], 2)
+          }.fixedSize()
+        }
+      } else {
+        Text("→").opacity(0.8)
+        ForEach(reverseLookupResult, id: \.self) { currentResult in
+          ZStack(alignment: .center) {
+            Color(white: colorScheme == .dark ? 0.3 : 0.9).cornerRadius(3)
+            Text("\(currentResult.trimmingCharacters(in: .newlines))")
+              .lineLimit(1).padding([.horizontal], 2)
+          }.fixedSize()
+        }
+      }
+    }
+    .font(.system(size: max(ceil(CandidateCellData.unifiedSize * 0.6), 9)))
+    .foregroundColor(colorScheme == .light ? Color(white: 0.1) : Color(white: 0.9))
+  }
+
+  var statusBar: some View {
+    HStack(alignment: .center) {
+      if !tooltip.isEmpty {
+        Text(tooltip).lineLimit(1)
+      } else {
+        if controller?.delegate?.showReverseLookupResult ?? true, tooltip.isEmpty {
+          reverseLookupPane.padding(0)
+        }
+      }
+      Spacer()
+      positionLabelView
+    }
+    .font(.system(size: max(ceil(CandidateCellData.unifiedSize * 0.7), 11), weight: .bold))
+    .padding([.bottom, .horizontal], 7).padding([.top], 2)
+    .fixedSize(horizontal: false, vertical: true)
+  }
+
+  var highlightBackgroundTDK: Color {
+    tooltip.isEmpty ? Color(white: colorScheme == .dark ? 0.2 : 0.9) : thePool.blankCell.themeColor
+  }
+
+  var candidateListBackground: some View {
+    Group {
+      absoluteBackgroundColor
+      if colorScheme == .dark {
+        Color.primary.opacity(0.05)
+      } else {
+        Color.primary.opacity(0.01)
+      }
+    }
+  }
+
+  var absoluteBackgroundColor: Color {
+    if colorScheme == .dark {
+      return Color(white: 0)
+    } else {
+      return Color(white: 1)
+    }
+  }
+
+  var bottomPanelBackgroundTDK: Color {
+    Color(white: colorScheme == .dark ? 0.145 : 0.95)
+  }
+
+  func attributedStringFor(cell theCell: CandidateCellData) -> some View {
+    let defaultResult = theCell.attributedStringForSwiftUIBackports
+    if forceCatalinaCompatibility {
+      return defaultResult
+    }
+    if #available(macOS 12, *) {
+      return theCell.attributedStringForSwiftUI
+    }
+    return defaultResult
+  }
+}
+
+// MARK: - Delegate Methods
+
+@available(macOS 10.15, *)
+extension VwrCandidateTDK {
+  func didSelectCandidateAt(_ pos: Int) {
+    controller?.delegate?.candidatePairSelected(at: pos)
+  }
+
+  func didRightClickCandidateAt(_ pos: Int, action: CandidateContextMenuAction) {
+    controller?.delegate?.candidatePairRightClicked(at: pos, action: action)
+  }
+}
+
+// MARK: - Preview
+
+import SwiftExtension
+
+@available(macOS 10.15, *)
+struct AttributedLabel_Previews: PreviewProvider {
+  @State static var testCandidates: [String] = [
+    "二十四歲是學生", "二十四歲", "昏睡紅茶", "食雪漢", "意味深", "學生", "便乗",
+    "🐂🍺🐂🍺", "🐃🍺", "🐂🍺", "🐃🐂🍺🍺", "🐂🍺", "🐃🍺", "🐂🍺", "🐃🍺", "🐂🍺", "🐃🍺",
+    "迫真", "驚愕", "論證", "正論", "惱", "悲", "屑", "食", "雪", "漢", "意", "味",
+    "深", "二", "十", "四", "歲", "是", "學", "生", "昏", "睡", "紅", "茶", "便", "乗",
+    "嗯", "哼", "啊",
+  ]
+  @State static var reverseLookupResult = ["mmmmm", "dddd"]
+  @State static var tooltip = "📼"
+  @State static var oldOS: Bool = true
+
+  static var thePoolX: CandidatePool {
+    var result = CandidatePool(
+      candidates: testCandidates, lines: 4,
+      selectionKeys: "123456", layout: .horizontal
+    )
+    result.reverseLookupResult = Self.reverseLookupResult
+    result.tooltip = Self.tooltip
+    result.highlight(at: 0)
+    return result
+  }
+
+  static var thePoolXS: CandidatePool {
+    var result = CandidatePool(
+      candidates: testCandidates, lines: 1,
+      selectionKeys: "123456", layout: .horizontal
+    )
+    result.reverseLookupResult = Self.reverseLookupResult
+    result.tooltip = Self.tooltip
+    result.highlight(at: 1)
+    return result
+  }
+
+  static var thePoolY: CandidatePool {
+    var result = CandidatePool(
+      candidates: testCandidates, lines: 4,
+      selectionKeys: "123456", layout: .vertical
+    )
+    result.reverseLookupResult = Self.reverseLookupResult
+    result.tooltip = Self.tooltip
+    result.flipPage(isBackward: false)
+    result.highlight(at: 2)
+    return result
+  }
+
+  static var thePoolYS: CandidatePool {
+    var result = CandidatePool(
+      candidates: testCandidates, lines: 1,
+      selectionKeys: "123456", layout: .vertical
+    )
+    result.reverseLookupResult = Self.reverseLookupResult
+    result.tooltip = Self.tooltip
+    result.highlight(at: 1)
+    return result
+  }
+
+  static var candidateListBackground: Color {
+    if NSApplication.isDarkMode {
+      return Color(white: 0.05)
+    } else {
+      return Color(white: 0.99)
+    }
+  }
+
+  static var previews: some View {
+    VStack {
+      HStack(alignment: .top) {
+        Text("田所選字窗 效能模式").bold().font(Font.system(.title))
+        VStack {
+          AttributedLabel(attributedString: Self.thePoolX.attributedDescription)
+            .padding(5)
+            .background(candidateListBackground)
+            .cornerRadius(10).fixedSize()
+          AttributedLabel(attributedString: Self.thePoolXS.attributedDescription)
+            .padding(5)
+            .background(candidateListBackground)
+            .cornerRadius(10).fixedSize()
+          HStack {
+            AttributedLabel(attributedString: Self.thePoolY.attributedDescription)
+              .padding(5)
+              .background(candidateListBackground)
+              .cornerRadius(10).fixedSize()
+            AttributedLabel(attributedString: Self.thePoolYS.attributedDescription)
+              .padding(5)
+              .background(candidateListBackground)
+              .cornerRadius(10).fixedSize()
+          }
+        }
+      }
+      Divider()
+      HStack(alignment: .top) {
+        Text("田所選字窗 SwiftUI 模式").bold().font(Font.system(.title))
+        VStack {
+          VwrCandidateTDK(controller: nil, thePool: thePoolX, forceCatalinaCompatibility: oldOS).fixedSize()
+          VwrCandidateTDK(controller: nil, thePool: thePoolXS, forceCatalinaCompatibility: oldOS).fixedSize()
+          HStack {
+            VwrCandidateTDK(controller: nil, thePool: thePoolY, forceCatalinaCompatibility: oldOS).fixedSize()
+            VwrCandidateTDK(controller: nil, thePool: thePoolYS, forceCatalinaCompatibility: oldOS).fixedSize()
+          }
+        }
+      }
+    }
+  }
+}

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/TDKCandidates/VwrCandidateTDK/VwrCandidateHorizontal.swift

@@ -1,161 +0,0 @@
-// (c) 2022 and onwards The vChewing Project (MIT-NTL License).
-// ====================
-// This code is released under the MIT license (SPDX-License-Identifier: MIT)
-// ... with NTL restriction stating that:
-// No trademark license is granted to use the trade names, trademarks, service
-// marks, or product names of Contributor, except as required to fulfill notice
-// requirements defined in MIT License.
-
-import Cocoa
-import Shared
-import SwiftUI
-
-// MARK: - Some useless tests
-
-@available(macOS 12, *)
-struct CandidatePoolViewUIHorizontal_Previews: PreviewProvider {
-  @State static var testCandidates: [String] = [
-    "二十四歲是學生", "二十四歲", "昏睡紅茶", "食雪漢", "意味深", "學生", "便乗",
-    "🐂🍺🐂🍺", "🐃🍺", "🐂🍺", "🐃🐂🍺🍺", "🐂🍺", "🐃🍺", "🐂🍺", "🐃🍺", "🐂🍺", "🐃🍺",
-    "迫真", "驚愕", "論證", "正論", "惱", "悲", "屑", "食", "雪", "漢", "意", "味",
-    "深", "二", "十", "四", "歲", "是", "學", "生", "昏", "睡", "紅", "茶", "便", "乗",
-    "嗯", "哼", "啊",
-  ]
-  static var thePool: CandidatePool {
-    var result = CandidatePool(candidates: testCandidates, rowCapacity: 6)
-    // 下一行待解決：無論這裡怎麼指定高亮選中項是哪一筆，其所在行都得被卷動到使用者眼前。
-    result.highlight(at: 5)
-    return result
-  }
-
-  static var previews: some View {
-    VwrCandidateHorizontal(controller: nil, thePool: thePool).fixedSize()
-  }
-}
-
-@available(macOS 12, *)
-public struct VwrCandidateHorizontal: View {
-  public weak var controller: CtlCandidateTDK?
-  @Environment(\.colorScheme) var colorScheme
-  @State public var thePool: CandidatePool
-  @State public var tooltip: String = ""
-  @State public var reverseLookupResult: [String] = []
-
-  private var positionLabel: String {
-    (thePool.highlightedIndex + 1).description + "/" + thePool.candidateDataAll.count.description
-  }
-
-  private func didSelectCandidateAt(_ pos: Int) {
-    if let delegate = controller?.delegate {
-      delegate.candidatePairSelected(at: pos)
-    }
-  }
-
-  private func didRightClickCandidateAt(_ pos: Int, action: CandidateContextMenuAction) {
-    if let delegate = controller?.delegate {
-      delegate.candidatePairRightClicked(at: pos, action: action)
-    }
-  }
-
-  public var body: some View {
-    VStack(alignment: .leading, spacing: 0) {
-      ScrollView(.vertical, showsIndicators: false) {
-        VStack(alignment: .leading, spacing: 1.6) {
-          ForEach(thePool.rangeForCurrentPage, id: \.self) { rowIndex in
-            HStack(spacing: ceil(CandidateCellData.unifiedSize * 0.35)) {
-              ForEach(Array(thePool.candidateLines[rowIndex]), id: \.self) { currentCandidate in
-                currentCandidate.attributedStringForSwiftUI.fixedSize()
-                  .contentShape(Rectangle())
-                  .frame(alignment: .topLeading)
-                  .onTapGesture { didSelectCandidateAt(currentCandidate.index) }
-                  .contextMenu {
-                    if controller?.delegate?.isCandidateContextMenuEnabled ?? false {
-                      Button {
-                        didRightClickCandidateAt(currentCandidate.index, action: .toBoost)
-                      } label: {
-                        Text("↑ " + currentCandidate.displayedText)
-                      }
-                      Button {
-                        didRightClickCandidateAt(currentCandidate.index, action: .toNerf)
-                      } label: {
-                        Text("↓ " + currentCandidate.displayedText)
-                      }
-                      Button {
-                        didRightClickCandidateAt(currentCandidate.index, action: .toFilter)
-                      } label: {
-                        Text("✖︎ " + currentCandidate.displayedText)
-                      }
-                    }
-                  }
-              }
-              Spacer()
-            }.frame(
-              minWidth: 0,
-              maxWidth: .infinity,
-              alignment: .topLeading
-            ).id(rowIndex)
-            Divider()
-          }
-          if thePool.maxLinesPerPage - thePool.rangeForCurrentPage.count > 0 {
-            ForEach(thePool.rangeForLastPageBlanked, id: \.self) { _ in
-              HStack(spacing: 0) {
-                thePool.blankCell.attributedStringForSwiftUI
-                  .contentShape(Rectangle())
-                  .frame(alignment: .topLeading)
-                Spacer()
-              }.frame(
-                minWidth: 0,
-                maxWidth: .infinity,
-                alignment: .topLeading
-              )
-              Divider()
-            }
-          }
-        }
-      }
-      .fixedSize(horizontal: false, vertical: true)
-      .padding([.horizontal], 5).padding([.top], 5).padding([.bottom], -1)
-      if controller?.delegate?.showReverseLookupResult ?? true {
-        ZStack(alignment: .leading) {
-          Color(white: colorScheme == .dark ? 0.15 : 0.97)
-          HStack(alignment: .center, spacing: 4) {
-            Text("→")
-            ForEach(reverseLookupResult, id: \.self) { currentResult in
-              ZStack(alignment: .center) {
-                Color(white: colorScheme == .dark ? 0.3 : 0.9).cornerRadius(3)
-                Text(" \(currentResult.trimmingCharacters(in: .newlines)) ").lineLimit(1)
-              }.fixedSize()
-            }
-          }
-          .font(.system(size: max(CandidateCellData.unifiedSize * 0.6, 9)))
-          .padding([.horizontal], 4).padding([.vertical], 4)
-          .foregroundColor(colorScheme == .light ? Color(white: 0.1) : Color(white: 0.9))
-        }
-      }
-      ZStack(alignment: .trailing) {
-        Color(nsColor: tooltip.isEmpty ? .windowBackgroundColor : CandidateCellData.highlightBackground)
-          .ignoresSafeArea()
-        HStack(alignment: .center) {
-          if !tooltip.isEmpty {
-            Text(tooltip).lineLimit(1)
-            Spacer()
-          }
-          Text(positionLabel).lineLimit(1)
-        }
-        .font(.system(size: max(CandidateCellData.unifiedSize * 0.7, 11), weight: .bold))
-        .padding(7).foregroundColor(
-          .init(nsColor: tooltip.isEmpty ? .controlTextColor : .selectedMenuItemTextColor.withAlphaComponent(0.9))
-        )
-      }
-      .fixedSize(horizontal: false, vertical: true)
-    }
-    .frame(minWidth: thePool.maxWindowWidth, maxWidth: thePool.maxWindowWidth)
-    .background(Color(nsColor: NSColor.controlBackgroundColor).ignoresSafeArea())
-    .overlay(
-      RoundedRectangle(cornerRadius: 10).stroke(
-        Color(white: colorScheme == .dark ? 0 : 1).opacity(colorScheme == .dark ? 1 : 0.1), lineWidth: 0.5
-      )
-    )
-    .cornerRadius(10)
-  }
-}

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/TDKCandidates/VwrCandidateTDK/VwrCandidateVertical.swift

@@ -1,171 +0,0 @@
-// (c) 2022 and onwards The vChewing Project (MIT-NTL License).
-// ====================
-// This code is released under the MIT license (SPDX-License-Identifier: MIT)
-// ... with NTL restriction stating that:
-// No trademark license is granted to use the trade names, trademarks, service
-// marks, or product names of Contributor, except as required to fulfill notice
-// requirements defined in MIT License.
-
-import Cocoa
-import Shared
-import SwiftUI
-
-// MARK: - Some useless tests
-
-@available(macOS 12, *)
-struct CandidatePoolViewUIVertical_Previews: PreviewProvider {
-  @State static var testCandidates: [String] = [
-    "二十四歲是學生", "二十四歲", "昏睡紅茶", "食雪漢", "意味深", "學生", "便乗",
-    "🐂🍺🐂🍺", "🐃🍺", "🐂🍺", "🐃🐂🍺🍺", "🐂🍺", "🐃🍺", "🐂🍺", "🐃🍺", "🐂🍺", "🐃🍺",
-    "迫真", "驚愕", "論證", "正論", "惱", "悲", "屑", "食", "雪", "漢", "意", "味",
-    "深", "二", "十", "四", "歲", "是", "學", "生", "昏", "睡", "紅", "茶", "便", "乗",
-    "嗯", "哼", "啊",
-  ]
-  static var thePool: CandidatePool {
-    var result = CandidatePool(candidates: testCandidates, columnCapacity: 6, selectionKeys: "123456789")
-    // 下一行待解決：無論這裡怎麼指定高亮選中項是哪一筆，其所在行都得被卷動到使用者眼前。
-    result.highlight(at: 5)
-    return result
-  }
-
-  static var previews: some View {
-    VwrCandidateVertical(controller: nil, thePool: thePool).fixedSize()
-  }
-}
-
-@available(macOS 12, *)
-public struct VwrCandidateVertical: View {
-  public weak var controller: CtlCandidateTDK?
-  @Environment(\.colorScheme) var colorScheme
-  @State public var thePool: CandidatePool
-  @State public var tooltip: String = ""
-  @State public var reverseLookupResult: [String] = []
-
-  private var positionLabel: String {
-    (thePool.highlightedIndex + 1).description + "/" + thePool.candidateDataAll.count.description
-  }
-
-  private func didSelectCandidateAt(_ pos: Int) {
-    if let delegate = controller?.delegate {
-      delegate.candidatePairSelected(at: pos)
-    }
-  }
-
-  private func didRightClickCandidateAt(_ pos: Int, action: CandidateContextMenuAction) {
-    if let delegate = controller?.delegate {
-      delegate.candidatePairRightClicked(at: pos, action: action)
-    }
-  }
-
-  public var body: some View {
-    VStack(alignment: .leading, spacing: 0) {
-      ScrollView(.horizontal, showsIndicators: false) {
-        HStack(alignment: .top, spacing: 10) {
-          ForEach(Array(thePool.rangeForCurrentPage.enumerated()), id: \.offset) { loopIndex, columnIndex in
-            VStack(alignment: .leading, spacing: 0) {
-              ForEach(Array(thePool.candidateLines[columnIndex]), id: \.self) { currentCandidate in
-                HStack(spacing: 0) {
-                  currentCandidate.attributedStringForSwiftUI.fixedSize(horizontal: false, vertical: true)
-                    .frame(
-                      maxWidth: .infinity,
-                      alignment: .topLeading
-                    )
-                    .contentShape(Rectangle())
-                    .onTapGesture { didSelectCandidateAt(currentCandidate.index) }
-                    .contextMenu {
-                      if controller?.delegate?.isCandidateContextMenuEnabled ?? false {
-                        Button {
-                          didRightClickCandidateAt(currentCandidate.index, action: .toBoost)
-                        } label: {
-                          Text("↑ " + currentCandidate.displayedText)
-                        }
-                        Button {
-                          didRightClickCandidateAt(currentCandidate.index, action: .toNerf)
-                        } label: {
-                          Text("↓ " + currentCandidate.displayedText)
-                        }
-                        Button {
-                          didRightClickCandidateAt(currentCandidate.index, action: .toFilter)
-                        } label: {
-                          Text("✖︎ " + currentCandidate.displayedText)
-                        }
-                      }
-                    }
-                }
-              }
-            }.frame(
-              minWidth: Double(CandidateCellData.unifiedSize * 5),
-              alignment: .topLeading
-            ).id(columnIndex)
-            if loopIndex < thePool.maxLinesPerPage - 1 {
-              Divider()
-            } else if thePool.maxLinesPerPage > 1 {
-              Spacer(minLength: 0)
-            }
-          }
-          if thePool.maxLinesPerPage - thePool.rangeForCurrentPage.count > 0 {
-            ForEach(Array(thePool.rangeForLastPageBlanked.enumerated()), id: \.offset) { loopIndex, _ in
-              VStack(alignment: .leading, spacing: 0) {
-                ForEach(0 ..< thePool.maxLineCapacity, id: \.self) { _ in
-                  thePool.blankCell.attributedStringForSwiftUI.fixedSize()
-                    .frame(width: Double(CandidateCellData.unifiedSize * 5), alignment: .topLeading)
-                    .contentShape(Rectangle())
-                }
-              }.frame(
-                minWidth: 0,
-                maxWidth: .infinity,
-                alignment: .topLeading
-              )
-              if loopIndex < thePool.maxLinesPerPage - thePool.rangeForCurrentPage.count - 1 {
-                Divider()
-              } else if thePool.maxLinesPerPage > 1 {
-                Spacer(minLength: 0)
-              }
-            }
-          }
-        }
-      }
-      .fixedSize(horizontal: true, vertical: false).padding(5)
-      if controller?.delegate?.showReverseLookupResult ?? true {
-        ZStack(alignment: .leading) {
-          Color(white: colorScheme == .dark ? 0.15 : 0.97)
-          HStack(alignment: .center, spacing: 4) {
-            Text("→")
-            ForEach(reverseLookupResult, id: \.self) { currentResult in
-              ZStack(alignment: .center) {
-                Color(white: colorScheme == .dark ? 0.3 : 0.9).cornerRadius(3)
-                Text(" \(currentResult.trimmingCharacters(in: .newlines)) ").lineLimit(1)
-              }.fixedSize()
-            }
-          }
-          .font(.system(size: max(CandidateCellData.unifiedSize * 0.6, 9)))
-          .padding([.horizontal], 4).padding([.vertical], 4)
-          .foregroundColor(colorScheme == .light ? Color(white: 0.1) : Color(white: 0.9))
-        }
-      }
-      ZStack(alignment: .trailing) {
-        Color(nsColor: tooltip.isEmpty ? .windowBackgroundColor : CandidateCellData.highlightBackground)
-          .ignoresSafeArea()
-        HStack(alignment: .center) {
-          if !tooltip.isEmpty {
-            Text(tooltip).lineLimit(1)
-            Spacer()
-          }
-          Text(positionLabel).lineLimit(1)
-        }
-        .font(.system(size: max(CandidateCellData.unifiedSize * 0.7, 11), weight: .bold))
-        .padding(7).foregroundColor(
-          .init(nsColor: tooltip.isEmpty ? .controlTextColor : .selectedMenuItemTextColor.withAlphaComponent(0.9))
-        )
-      }
-      .fixedSize(horizontal: false, vertical: true)
-    }
-    .background(Color(nsColor: NSColor.controlBackgroundColor).ignoresSafeArea())
-    .overlay(
-      RoundedRectangle(cornerRadius: 10).stroke(
-        Color(white: colorScheme == .dark ? 0 : 1).opacity(colorScheme == .dark ? 1 : 0.1), lineWidth: 0.5
-      )
-    )
-    .cornerRadius(10)
-  }
-}

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/TDKCandidates/VwrCandidateTDK_Backports/VwrCandidateHorizontalBackports.swift

@@ -1,166 +0,0 @@
-// (c) 2022 and onwards The vChewing Project (MIT-NTL License).
-// ====================
-// This code is released under the MIT license (SPDX-License-Identifier: MIT)
-// ... with NTL restriction stating that:
-// No trademark license is granted to use the trade names, trademarks, service
-// marks, or product names of Contributor, except as required to fulfill notice
-// requirements defined in MIT License.
-
-import Cocoa
-import Shared
-import SwiftUI
-import SwiftUIBackports
-
-// MARK: - Some useless tests
-
-@available(macOS 10.15, *)
-struct CandidatePoolViewUIHorizontalBackports_Previews: PreviewProvider {
-  @State static var testCandidates: [String] = [
-    "二十四歲是學生", "二十四歲", "昏睡紅茶", "食雪漢", "意味深", "學生", "便乗",
-    "🐂🍺🐂🍺", "🐃🍺", "🐂🍺", "🐃🐂🍺🍺", "🐂🍺", "🐃🍺", "🐂🍺", "🐃🍺", "🐂🍺", "🐃🍺",
-    "迫真", "驚愕", "論證", "正論", "惱", "悲", "屑", "食", "雪", "漢", "意", "味",
-    "深", "二", "十", "四", "歲", "是", "學", "生", "昏", "睡", "紅", "茶", "便", "乗",
-    "嗯", "哼", "啊",
-  ]
-  static var thePool: CandidatePool {
-    var result = CandidatePool(candidates: testCandidates, rowCapacity: 6)
-    // 下一行待解決：無論這裡怎麼指定高亮選中項是哪一筆，其所在行都得被卷動到使用者眼前。
-    result.highlight(at: 5)
-    return result
-  }
-
-  static var previews: some View {
-    VwrCandidateHorizontalBackports(controller: nil, thePool: thePool).fixedSize()
-  }
-}
-
-@available(macOS 10.15, *)
-public struct VwrCandidateHorizontalBackports: View {
-  public weak var controller: CtlCandidateTDK?
-  @Environment(\.colorScheme) var colorScheme
-  @State public var thePool: CandidatePool
-  @State public var tooltip: String = ""
-  @State public var reverseLookupResult: [String] = []
-
-  private var positionLabel: String {
-    (thePool.highlightedIndex + 1).description + "/" + thePool.candidateDataAll.count.description
-  }
-
-  private func didSelectCandidateAt(_ pos: Int) {
-    if let delegate = controller?.delegate {
-      delegate.candidatePairSelected(at: pos)
-    }
-  }
-
-  private func didRightClickCandidateAt(_ pos: Int, action: CandidateContextMenuAction) {
-    if let delegate = controller?.delegate {
-      delegate.candidatePairRightClicked(at: pos, action: action)
-    }
-  }
-
-  public var body: some View {
-    VStack(alignment: .leading, spacing: 0) {
-      ScrollView(.vertical, showsIndicators: false) {
-        VStack(alignment: .leading, spacing: 1.6) {
-          ForEach(thePool.rangeForCurrentPage, id: \.self) { rowIndex in
-            HStack(spacing: ceil(CandidateCellData.unifiedSize * 0.35)) {
-              ForEach(Array(thePool.candidateLines[rowIndex]), id: \.self) { currentCandidate in
-                currentCandidate.attributedStringForSwiftUIBackports.fixedSize()
-                  .contentShape(Rectangle())
-                  .frame(alignment: .topLeading)
-                  .onTapGesture { didSelectCandidateAt(currentCandidate.index) }
-                  .contextMenu {
-                    if controller?.delegate?.isCandidateContextMenuEnabled ?? false {
-                      Button {
-                        didRightClickCandidateAt(currentCandidate.index, action: .toBoost)
-                      } label: {
-                        Text("↑ " + currentCandidate.displayedText)
-                      }
-                      Button {
-                        didRightClickCandidateAt(currentCandidate.index, action: .toNerf)
-                      } label: {
-                        Text("↓ " + currentCandidate.displayedText)
-                      }
-                      Button {
-                        didRightClickCandidateAt(currentCandidate.index, action: .toFilter)
-                      } label: {
-                        Text("✖︎ " + currentCandidate.displayedText)
-                      }
-                    }
-                  }
-              }
-              Spacer()
-            }.frame(
-              minWidth: 0,
-              maxWidth: .infinity,
-              alignment: .topLeading
-            ).id(rowIndex)
-            Divider()
-          }
-          if thePool.maxLinesPerPage - thePool.rangeForCurrentPage.count > 0 {
-            ForEach(thePool.rangeForLastPageBlanked, id: \.self) { _ in
-              HStack(spacing: 0) {
-                thePool.blankCell.attributedStringForSwiftUIBackports
-                  .contentShape(Rectangle())
-                  .frame(alignment: .topLeading)
-                Spacer()
-              }.frame(
-                minWidth: 0,
-                maxWidth: .infinity,
-                alignment: .topLeading
-              )
-              Divider()
-            }
-          }
-        }
-      }
-      .fixedSize(horizontal: false, vertical: true)
-      .padding([.horizontal], 5).padding([.top], 5).padding([.bottom], -1)
-      if controller?.delegate?.showReverseLookupResult ?? true {
-        ZStack(alignment: .leading) {
-          Color(white: colorScheme == .dark ? 0.15 : 0.97)
-          HStack(alignment: .center, spacing: 4) {
-            Text("→")
-            ForEach(reverseLookupResult, id: \.self) { currentResult in
-              ZStack(alignment: .center) {
-                Color(white: colorScheme == .dark ? 0.3 : 0.9).cornerRadius(3)
-                Text(" \(currentResult.trimmingCharacters(in: .newlines)) ").lineLimit(1)
-              }.fixedSize()
-            }
-          }
-          .font(.system(size: max(CandidateCellData.unifiedSize * 0.6, 9)))
-          .padding([.horizontal], 4).padding([.vertical], 4)
-          .foregroundColor(colorScheme == .light ? Color(white: 0.1) : Color(white: 0.9))
-        }
-      }
-      ZStack(alignment: .trailing) {
-        if tooltip.isEmpty {
-          Color(white: colorScheme == .dark ? 0.2 : 0.9)
-        } else {
-          Color(white: colorScheme == .dark ? 0.0 : 1)
-          controller?.highlightedColorUIBackports
-        }
-        HStack(alignment: .center) {
-          if !tooltip.isEmpty {
-            Text(tooltip).lineLimit(1)
-            Spacer()
-          }
-          Text(positionLabel).lineLimit(1)
-        }
-        .font(.system(size: max(CandidateCellData.unifiedSize * 0.7, 11), weight: .bold))
-        .padding(7).foregroundColor(
-          tooltip.isEmpty && colorScheme == .light ? Color(white: 0.1) : Color(white: 0.9)
-        )
-      }
-      .fixedSize(horizontal: false, vertical: true)
-    }
-    .frame(minWidth: thePool.maxWindowWidth, maxWidth: thePool.maxWindowWidth)
-    .background(Color(white: colorScheme == .dark ? 0.1 : 1))
-    .overlay(
-      RoundedRectangle(cornerRadius: 10).stroke(
-        Color(white: colorScheme == .dark ? 0 : 1).opacity(colorScheme == .dark ? 1 : 0.1), lineWidth: 0.5
-      )
-    )
-    .cornerRadius(10)
-  }
-}

Packages/vChewing_CandidateWindow/Sources/CandidateWindow/TDKCandidates/VwrCandidateTDK_Backports/VwrCandidateVerticalBackports.swift

@@ -1,176 +0,0 @@
-// (c) 2022 and onwards The vChewing Project (MIT-NTL License).
-// ====================
-// This code is released under the MIT license (SPDX-License-Identifier: MIT)
-// ... with NTL restriction stating that:
-// No trademark license is granted to use the trade names, trademarks, service
-// marks, or product names of Contributor, except as required to fulfill notice
-// requirements defined in MIT License.
-
-import Cocoa
-import Shared
-import SwiftUI
-import SwiftUIBackports
-
-// MARK: - Some useless tests
-
-@available(macOS 10.15, *)
-struct CandidatePoolViewUIVerticalBackports_Previews: PreviewProvider {
-  @State static var testCandidates: [String] = [
-    "二十四歲是學生", "二十四歲", "昏睡紅茶", "食雪漢", "意味深", "學生", "便乗",
-    "🐂🍺🐂🍺", "🐃🍺", "🐂🍺", "🐃🐂🍺🍺", "🐂🍺", "🐃🍺", "🐂🍺", "🐃🍺", "🐂🍺", "🐃🍺",
-    "迫真", "驚愕", "論證", "正論", "惱", "悲", "屑", "食", "雪", "漢", "意", "味",
-    "深", "二", "十", "四", "歲", "是", "學", "生", "昏", "睡", "紅", "茶", "便", "乗",
-    "嗯", "哼", "啊",
-  ]
-  static var thePool: CandidatePool {
-    var result = CandidatePool(candidates: testCandidates, columnCapacity: 6, selectionKeys: "123456789")
-    // 下一行待解決：無論這裡怎麼指定高亮選中項是哪一筆，其所在行都得被卷動到使用者眼前。
-    result.highlight(at: 5)
-    return result
-  }
-
-  static var previews: some View {
-    VwrCandidateVerticalBackports(controller: nil, thePool: thePool).fixedSize()
-  }
-}
-
-@available(macOS 10.15, *)
-public struct VwrCandidateVerticalBackports: View {
-  public weak var controller: CtlCandidateTDK?
-  @Environment(\.colorScheme) var colorScheme
-  @State public var thePool: CandidatePool
-  @State public var tooltip: String = ""
-  @State public var reverseLookupResult: [String] = []
-
-  private var positionLabel: String {
-    (thePool.highlightedIndex + 1).description + "/" + thePool.candidateDataAll.count.description
-  }
-
-  private func didSelectCandidateAt(_ pos: Int) {
-    if let delegate = controller?.delegate {
-      delegate.candidatePairSelected(at: pos)
-    }
-  }
-
-  private func didRightClickCandidateAt(_ pos: Int, action: CandidateContextMenuAction) {
-    if let delegate = controller?.delegate {
-      delegate.candidatePairRightClicked(at: pos, action: action)
-    }
-  }
-
-  public var body: some View {
-    VStack(alignment: .leading, spacing: 0) {
-      ScrollView(.horizontal, showsIndicators: false) {
-        HStack(alignment: .top, spacing: 10) {
-          ForEach(Array(thePool.rangeForCurrentPage.enumerated()), id: \.offset) { loopIndex, columnIndex in
-            VStack(alignment: .leading, spacing: 0) {
-              ForEach(Array(thePool.candidateLines[columnIndex]), id: \.self) { currentCandidate in
-                HStack(spacing: 0) {
-                  currentCandidate.attributedStringForSwiftUIBackports.fixedSize(horizontal: false, vertical: true)
-                    .frame(
-                      maxWidth: .infinity,
-                      alignment: .topLeading
-                    )
-                    .contentShape(Rectangle())
-                    .onTapGesture { didSelectCandidateAt(currentCandidate.index) }
-                    .contextMenu {
-                      if controller?.delegate?.isCandidateContextMenuEnabled ?? false {
-                        Button {
-                          didRightClickCandidateAt(currentCandidate.index, action: .toBoost)
-                        } label: {
-                          Text("↑ " + currentCandidate.displayedText)
-                        }
-                        Button {
-                          didRightClickCandidateAt(currentCandidate.index, action: .toNerf)
-                        } label: {
-                          Text("↓ " + currentCandidate.displayedText)
-                        }
-                        Button {
-                          didRightClickCandidateAt(currentCandidate.index, action: .toFilter)
-                        } label: {
-                          Text("✖︎ " + currentCandidate.displayedText)
-                        }
-                      }
-                    }
-                }
-              }
-            }.frame(
-              minWidth: Double(CandidateCellData.unifiedSize * 5),
-              alignment: .topLeading
-            ).id(columnIndex)
-            if loopIndex < thePool.maxLinesPerPage - 1 {
-              Divider()
-            } else if thePool.maxLinesPerPage > 1 {
-              Spacer(minLength: 0)
-            }
-          }
-          if thePool.maxLinesPerPage - thePool.rangeForCurrentPage.count > 0 {
-            ForEach(Array(thePool.rangeForLastPageBlanked.enumerated()), id: \.offset) { loopIndex, _ in
-              VStack(alignment: .leading, spacing: 0) {
-                ForEach(0 ..< thePool.maxLineCapacity, id: \.self) { _ in
-                  thePool.blankCell.attributedStringForSwiftUIBackports.fixedSize()
-                    .frame(width: Double(CandidateCellData.unifiedSize * 5), alignment: .topLeading)
-                    .contentShape(Rectangle())
-                }
-              }.frame(
-                minWidth: 0,
-                maxWidth: .infinity,
-                alignment: .topLeading
-              )
-              if loopIndex < thePool.maxLinesPerPage - thePool.rangeForCurrentPage.count - 1 {
-                Divider()
-              } else if thePool.maxLinesPerPage > 1 {
-                Spacer(minLength: 0)
-              }
-            }
-          }
-        }
-      }
-      .fixedSize(horizontal: true, vertical: false).padding(5)
-      if controller?.delegate?.showReverseLookupResult ?? true {
-        ZStack(alignment: .leading) {
-          Color(white: colorScheme == .dark ? 0.15 : 0.97)
-          HStack(alignment: .center, spacing: 4) {
-            Text("→")
-            ForEach(reverseLookupResult, id: \.self) { currentResult in
-              ZStack(alignment: .center) {
-                Color(white: colorScheme == .dark ? 0.3 : 0.9).cornerRadius(3)
-                Text(" \(currentResult.trimmingCharacters(in: .newlines)) ").lineLimit(1)
-              }.fixedSize()
-            }
-          }
-          .font(.system(size: max(CandidateCellData.unifiedSize * 0.6, 9)))
-          .padding([.horizontal], 4).padding([.vertical], 4)
-          .foregroundColor(colorScheme == .light ? Color(white: 0.1) : Color(white: 0.9))
-        }
-      }
-      ZStack(alignment: .trailing) {
-        if tooltip.isEmpty {
-          Color(white: colorScheme == .dark ? 0.2 : 0.9)
-        } else {
-          Color(white: colorScheme == .dark ? 0.0 : 1)
-          controller?.highlightedColorUIBackports
-        }
-        HStack(alignment: .center) {
-          if !tooltip.isEmpty {
-            Text(tooltip).lineLimit(1)
-            Spacer()
-          }
-          Text(positionLabel).lineLimit(1)
-        }
-        .font(.system(size: max(CandidateCellData.unifiedSize * 0.7, 11), weight: .bold))
-        .padding(7).foregroundColor(
-          tooltip.isEmpty && colorScheme == .light ? Color(white: 0.1) : Color(white: 0.9)
-        )
-      }
-      .fixedSize(horizontal: false, vertical: true)
-    }
-    .background(Color(white: colorScheme == .dark ? 0.1 : 1))
-    .overlay(
-      RoundedRectangle(cornerRadius: 10).stroke(
-        Color(white: colorScheme == .dark ? 0 : 1).opacity(colorScheme == .dark ? 1 : 0.1), lineWidth: 0.5
-      )
-    )
-    .cornerRadius(10)
-  }
-}

Packages/vChewing_CandidateWindow/Tests/CandidateWindowTests/CandidatePoolTests.swift

@@ -20,7 +20,7 @@ final class CandidatePoolTests: XCTestCase {
   ]
 
   func testPoolHorizontal() throws {
-    let pool = CandidatePool(candidates: testCandidates, rowCapacity: 6)
+    let pool = CandidatePool(candidates: testCandidates, selectionKeys: "123456", layout: .horizontal)
     var strOutput = ""
     pool.candidateLines.forEach {
       $0.forEach {
@@ -33,7 +33,7 @@ final class CandidatePoolTests: XCTestCase {
   }
 
   func testPoolVertical() throws {
-    let pool = CandidatePool(candidates: testCandidates, columnCapacity: 6)
+    let pool = CandidatePool(candidates: testCandidates, selectionKeys: "123456", layout: .vertical)
     var strOutput = ""
     pool.candidateLines.forEach {
       $0.forEach {

Source/Modules/PrefMgr_Extension.swift

@@ -14,7 +14,6 @@ public extension PrefMgr {
   func fixOddPreferences() {
     // macOS 10.15 開始才能使用 SwiftUI 構建的田所選字窗。
     if #unavailable(macOS 10.15) {
-      useIMKCandidateWindow = true
       legacyCandidateViewTypesettingMethodEnabled = false
       togglingAlphanumericalModeWithRShift = false
       togglingAlphanumericalModeWithLShift = false

Source/Modules/SessionCtl_HandleDisplay.swift

@@ -86,15 +86,15 @@ public extension SessionCtl {
     /// 先取消既有的選字窗的內容顯示。否則可能會重複生成選字窗的 NSWindow()。
     candidateUI?.visible = false
     /// 然後再重新初期化。
-    if #available(macOS 10.15, *) {
+    if #available(macOS 10.13, *) {
       candidateUI =
         PrefMgr.shared.useIMKCandidateWindow
           ? CtlCandidateIMK(candidateLayout) : CtlCandidateTDK(candidateLayout)
       if let candidateTDK = candidateUI as? CtlCandidateTDK {
-        candidateTDK.maxLinesPerPage = isVerticalTyping ? 1 : 3
+        candidateTDK.maxLinesPerPage = isVerticalTyping ? 1 : 4
       }
     } else {
-      candidateUI = CtlCandidateIMK(candidateLayout)
+      candidateUI = CtlCandidateTDK(candidateLayout)
     }
 
     candidateUI?.candidateFont = Self.candidateFont(