1.5.x Beta // Merge GitHub PR #63 from dev/1.5.x

KeyHandler Swiftification.
2022-04-18 01:46:26 +08:00 · 2022-04-18 01:46:26 +08:00 · ed834623eb
parent 61d1e4ab8e daaf0249b9
commit ed834623eb
11 changed files with 1722 additions and 1415 deletions
--- a/Source/3rdParty/OVMandarin/Mandarin.h
+++ b/Source/3rdParty/OVMandarin/Mandarin.h
@ -210,7 +210,7 @@ typedef BopomofoSyllable BPMF;
 typedef std::map<char, std::vector<BPMF::Component>> BopomofoKeyToComponentMap;
 typedef std::map<BPMF::Component, char> BopomofoComponentToKeyMap;

-class BopomofoKeyboardLayout
+extern "C" class BopomofoKeyboardLayout
 {
  public:
    static const BopomofoKeyboardLayout *StandardLayout();
@ -438,7 +438,7 @@ class BopomofoKeyboardLayout
    BopomofoComponentToKeyMap m_componentToKey;
 };

-class BopomofoReadingBuffer
+extern "C" class BopomofoReadingBuffer
 {
  public:
    explicit BopomofoReadingBuffer(const BopomofoKeyboardLayout *layout) : layout_(layout), pinyin_mode_(false)
--- a/Source/Modules/ControllerModules/KeyHandler.h
+++ b/Source/Modules/ControllerModules/KeyHandler.h
@ -36,6 +36,14 @@ extern InputMode imeModeCHT;
 extern InputMode imeModeCHS;
 extern InputMode imeModeNULL;

+struct BufferStatePackage
+{
+    NSString *composedText;
+    NSInteger cursorIndex;
+    NSString *resultOfBefore;
+    NSString *resultOfAfter;
+};
+
@class KeyHandler;

@protocol KeyHandlerDelegate <NSObject>
@ -47,21 +55,48 @@ extern InputMode imeModeNULL;
@interface KeyHandler : NSObject

 - (BOOL)isBuilderEmpty;
- (BOOL)handleInput:(keyParser *)input
-              state:(InputState *)state
-      stateCallback:(void (^)(InputState *))stateCallback
-      errorCallback:(void (^)(void))errorCallback
-    NS_SWIFT_NAME(handle(input:state:stateCallback:errorCallback:));

- (void)syncWithPreferences;
 - (void)fixNodeWithValue:(NSString *)value NS_SWIFT_NAME(fixNode(value:));
 - (void)clear;

- (InputState *)buildInputtingState;
 - (nullable InputState *)buildAssociatePhraseStateWithKey:(NSString *)key useVerticalMode:(BOOL)useVerticalMode;

@property(strong, nonatomic) InputMode inputMode;
@property(weak, nonatomic) id<KeyHandlerDelegate> delegate;
+
+// The following items need to be exposed to Swift:
+- (void)_walk;
+- (NSString *)_popOverflowComposingTextAndWalk;
+- (NSArray<NSString *> *)_currentReadings;
+
+- (BOOL)checkWhetherToneMarkerConfirmsPhoneticReadingBuffer;
+- (BOOL)chkKeyValidity:(UniChar)value;
+- (BOOL)ifLangModelHasUnigramsForKey:(NSString *)reading;
+- (BOOL)isPhoneticReadingBufferEmpty;
+- (BOOL)isPrintable:(UniChar)charCode;
+- (NSArray<NSString *> *)getCandidatesArray;
+- (NSInteger)getBuilderCursorIndex;
+- (NSInteger)getBuilderLength;
+- (NSInteger)getPackagedCursorIndex;
+- (NSString *)getComposedText;
+- (NSString *)getCompositionFromPhoneticReadingBuffer;
+- (NSString *)getStrLocationResult:(BOOL)isAfter NS_SWIFT_NAME(getStrLocationResult(isAfter:));
+- (NSString *)getSyllableCompositionFromPhoneticReadingBuffer;
+- (void)clearPhoneticReadingBuffer;
+- (void)combinePhoneticReadingBufferKey:(UniChar)charCode;
+- (void)createNewBuilder;
+- (void)dealWithOverrideModelSuggestions;
+- (void)deleteBuilderReadingAfterCursor;
+- (void)deleteBuilderReadingInFrontOfCursor;
+- (void)doBackSpaceToPhoneticReadingBuffer;
+- (void)ensurePhoneticParser;
+- (void)insertReadingToBuilderAtCursor:(NSString *)reading;
+- (void)packageBufferStateMaterials;
+- (void)removeBuilderAndReset:(BOOL)shouldReset;
+- (void)setBuilderCursorIndex:(NSInteger)value;
+- (void)setInputModesToLM:(BOOL)isCHS;
+- (void)syncBaseLMPrefs;
+
@end

 NS_ASSUME_NONNULL_END
--- a/Source/Modules/ControllerModules/KeyHandler.mm
+++ b/Source/Modules/ControllerModules/KeyHandler.mm
--- a/Source/Modules/ControllerModules/KeyHandler_HandleCandidate.swift
+++ b/Source/Modules/ControllerModules/KeyHandler_HandleCandidate.swift
@ -0,0 +1,329 @@
+// Copyright (c) 2021 and onwards The vChewing Project (MIT-NTL License).
+// Refactored from the ObjCpp-version of this class by:
+// (c) 2011 and onwards The OpenVanilla Project (MIT License).
+/*
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+1. The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+2. 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 above.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+import Cocoa
+
+// MARK: - § Handle Candidate State.
+@objc extension KeyHandler {
+	func _handleCandidateState(
+		_ state: InputState,
+		input: keyParser,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		let inputText = input.inputText
+		let charCode: UniChar = input.charCode
+		let ctlCandidateCurrent = delegate!.ctlCandidate(for: self) as! ctlCandidate
+
+		let cancelCandidateKey =
+			input.isBackSpace || input.isESC || input.isDelete
+			|| ((input.isCursorBackward || input.isCursorForward) && input.isShiftHold)
+
+		if cancelCandidateKey {
+			if state is InputState.AssociatedPhrases {
+				clear()
+				let empty = InputState.EmptyIgnoringPreviousState()
+				stateCallback(empty)
+			} else if mgrPrefs.useSCPCTypingMode {
+				clear()
+				let empty = InputState.EmptyIgnoringPreviousState()
+				stateCallback(empty)
+			} else if isBuilderEmpty() {
+				// 如果此時發現當前組字緩衝區為真空的情況的話，
+				// 就將當前的組字緩衝區析構處理、強制重設輸入狀態。
+				// 否則，一個本不該出現的真空組字緩衝區會使前後方向鍵與 BackSpace 鍵失靈。
+				clear()
+				let empty = InputState.EmptyIgnoringPreviousState()
+				stateCallback(empty)
+			} else {
+				let inputting = buildInputtingState()
+				stateCallback(inputting)
+			}
+			return true
+		}
+
+		if input.isEnter {
+			if state is InputState.AssociatedPhrases {
+				clear()
+				let empty = InputState.EmptyIgnoringPreviousState()
+				stateCallback(empty)
+				return true
+			}
+			delegate!.keyHandler(
+				self,
+				didSelectCandidateAt: Int(ctlCandidateCurrent.selectedCandidateIndex),
+				ctlCandidate: ctlCandidateCurrent)
+			return true
+		}
+
+		if input.isTab {
+			let updated: Bool =
+				mgrPrefs.specifyShiftTabKeyBehavior
+				? (input.isShiftHold ? ctlCandidateCurrent.showPreviousPage() : ctlCandidateCurrent.showNextPage())
+				: (input.isShiftHold
+					? ctlCandidateCurrent.highlightPreviousCandidate()
+					: ctlCandidateCurrent.highlightNextCandidate())
+			if !updated {
+				IME.prtDebugIntel("9B691919")
+				errorCallback()
+			}
+			return true
+		}
+
+		if input.isSpace {
+			let updated: Bool =
+				mgrPrefs.specifyShiftSpaceKeyBehavior
+				? (input.isShiftHold
+					? ctlCandidateCurrent.highlightNextCandidate()
+					: ctlCandidateCurrent.showNextPage())
+				: (input.isShiftHold
+					? ctlCandidateCurrent.showNextPage()
+					: ctlCandidateCurrent.highlightNextCandidate())
+			if !updated {
+				IME.prtDebugIntel("A11C781F")
+				errorCallback()
+			}
+			return true
+		}
+
+		if input.isPageDown || input.emacsKey == vChewingEmacsKey.nextPage {
+			let updated: Bool = ctlCandidateCurrent.showNextPage()
+			if !updated {
+				IME.prtDebugIntel("9B691919")
+				errorCallback()
+			}
+			return true
+		}
+
+		if input.isPageUp {
+			let updated: Bool = ctlCandidateCurrent.showPreviousPage()
+			if !updated {
+				IME.prtDebugIntel("9569955D")
+				errorCallback()
+			}
+			return true
+		}
+
+		if input.isLeft {
+			if ctlCandidateCurrent is ctlCandidateHorizontal {
+				let updated: Bool = ctlCandidateCurrent.highlightPreviousCandidate()
+				if !updated {
+					IME.prtDebugIntel("1145148D")
+					errorCallback()
+				}
+			} else {
+				let updated: Bool = ctlCandidateCurrent.showPreviousPage()
+				if !updated {
+					IME.prtDebugIntel("1919810D")
+					errorCallback()
+				}
+			}
+			return true
+		}
+
+		if input.emacsKey == vChewingEmacsKey.backward {
+			let updated: Bool = ctlCandidateCurrent.highlightPreviousCandidate()
+			if !updated {
+				IME.prtDebugIntel("9B89308D")
+				errorCallback()
+			}
+			return true
+		}
+
+		if input.isRight {
+			if ctlCandidateCurrent is ctlCandidateHorizontal {
+				let updated: Bool = ctlCandidateCurrent.highlightNextCandidate()
+				if !updated {
+					IME.prtDebugIntel("9B65138D")
+					errorCallback()
+				}
+			} else {
+				let updated: Bool = ctlCandidateCurrent.showNextPage()
+				if !updated {
+					IME.prtDebugIntel("9244908D")
+					errorCallback()
+				}
+			}
+			return true
+		}
+
+		if input.emacsKey == vChewingEmacsKey.forward {
+			let updated: Bool = ctlCandidateCurrent.highlightNextCandidate()
+			if !updated {
+				IME.prtDebugIntel("9B2428D")
+				errorCallback()
+			}
+			return true
+		}
+
+		if input.isUp {
+			if ctlCandidateCurrent is ctlCandidateHorizontal {
+				let updated: Bool = ctlCandidateCurrent.showPreviousPage()
+				if !updated {
+					IME.prtDebugIntel("9B614524")
+					errorCallback()
+				}
+			} else {
+				let updated: Bool = ctlCandidateCurrent.highlightPreviousCandidate()
+				if !updated {
+					IME.prtDebugIntel("ASD9908D")
+					errorCallback()
+				}
+			}
+			return true
+		}
+
+		if input.isDown {
+			if ctlCandidateCurrent is ctlCandidateHorizontal {
+				let updated: Bool = ctlCandidateCurrent.showNextPage()
+				if !updated {
+					IME.prtDebugIntel("92B990DD")
+					errorCallback()
+				}
+			} else {
+				let updated: Bool = ctlCandidateCurrent.highlightNextCandidate()
+				if !updated {
+					IME.prtDebugIntel("6B99908D")
+					errorCallback()
+				}
+			}
+			return true
+		}
+
+		if input.isHome || input.emacsKey == vChewingEmacsKey.home {
+			if ctlCandidateCurrent.selectedCandidateIndex == 0 {
+				IME.prtDebugIntel("9B6EDE8D")
+				errorCallback()
+			} else {
+				ctlCandidateCurrent.selectedCandidateIndex = 0
+			}
+
+			return true
+		}
+
+		var candidates: [String]!
+
+		if state is InputState.ChoosingCandidate {
+			candidates = (state as! InputState.ChoosingCandidate).candidates
+		} else if state is InputState.AssociatedPhrases {
+			candidates = (state as! InputState.AssociatedPhrases).candidates
+		}
+
+		if candidates.isEmpty { return false }
+
+		if (input.isEnd || input.emacsKey == vChewingEmacsKey.end) && candidates.count > 0 {
+			if ctlCandidateCurrent.selectedCandidateIndex == UInt(candidates.count - 1) {
+				IME.prtDebugIntel("9B69AAAD")
+				errorCallback()
+			} else {
+				ctlCandidateCurrent.selectedCandidateIndex = UInt(candidates.count - 1)
+			}
+
+			return true
+		}
+
+		if state is InputState.AssociatedPhrases {
+			if !input.isShiftHold { return false }
+		}
+
+		var index: Int = NSNotFound
+		var match: String!
+		if state is InputState.AssociatedPhrases { match = input.inputTextIgnoringModifiers } else { match = inputText }
+
+		var j = 0
+		while j < ctlCandidateCurrent.keyLabels.count {
+			let label: CandidateKeyLabel = ctlCandidateCurrent.keyLabels[j]
+			if match.compare(label.key, options: .caseInsensitive, range: nil, locale: .current) == .orderedSame {
+				index = j
+				break
+			}
+			j += 1
+		}
+
+		if index != NSNotFound {
+			let candidateIndex: UInt = ctlCandidateCurrent.candidateIndexAtKeyLabelIndex(UInt(index))
+			if candidateIndex != UInt.max {
+				delegate!.keyHandler(self, didSelectCandidateAt: Int(candidateIndex), ctlCandidate: ctlCandidateCurrent)
+				return true
+			}
+		}
+
+		if state is InputState.AssociatedPhrases { return false }
+
+		if mgrPrefs.useSCPCTypingMode {
+			var punctuationNamePrefix = ""
+
+			if input.isOptionHold {
+				punctuationNamePrefix = "_alt_punctuation_"
+			} else if input.isControlHold {
+				punctuationNamePrefix = "_ctrl_punctuation_"
+			} else if mgrPrefs.halfWidthPunctuationEnabled {
+				punctuationNamePrefix = "_half_punctuation_"
+			} else {
+				punctuationNamePrefix = "_punctuation_"
+			}
+
+			let parser = getCurrentMandarinParser()
+
+			let arrCustomPunctuations: [String] = [
+				punctuationNamePrefix, parser, String(format: "%c", CChar(charCode)),
+			]
+			let customPunctuation: String = arrCustomPunctuations.joined(separator: "")
+
+			let arrPunctuations: [String] = [punctuationNamePrefix, String(format: "%c", CChar(charCode))]
+			let punctuation: String = arrPunctuations.joined(separator: "")
+
+			var shouldAutoSelectCandidate: Bool =
+				chkKeyValidity(charCode) || ifLangModelHasUnigrams(forKey: customPunctuation)
+				|| ifLangModelHasUnigrams(forKey: punctuation)
+
+			if !shouldAutoSelectCandidate && input.isUpperCaseASCIILetterKey {
+				let letter: String! = String(format: "%@%c", "_letter_", CChar(charCode))
+				if ifLangModelHasUnigrams(forKey: letter) { shouldAutoSelectCandidate = true }
+			}
+
+			if shouldAutoSelectCandidate {
+				let candidateIndex: UInt = ctlCandidateCurrent.candidateIndexAtKeyLabelIndex(0)
+				if candidateIndex != UInt.max {
+					delegate!.keyHandler(
+						self,
+						didSelectCandidateAt: Int(candidateIndex),
+						ctlCandidate: ctlCandidateCurrent)
+					clear()
+					let empty = InputState.EmptyIgnoringPreviousState()
+					stateCallback(empty)
+					return handle(
+						input: input, state: empty, stateCallback: stateCallback, errorCallback: errorCallback)
+				}
+				return true
+			}
+		}
+
+		IME.prtDebugIntel("172A0F81")
+		errorCallback()
+		return true
+	}
+}
--- a/Source/Modules/ControllerModules/KeyHandler_HandleInput.swift
+++ b/Source/Modules/ControllerModules/KeyHandler_HandleInput.swift
@ -0,0 +1,426 @@
+// Copyright (c) 2021 and onwards The vChewing Project (MIT-NTL License).
+// Refactored from the ObjCpp-version of this class by:
+// (c) 2011 and onwards The OpenVanilla Project (MIT License).
+/*
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+1. The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+2. 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 above.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+import Cocoa
+
+// MARK: - § Handle Input with States.
+
+@objc extension KeyHandler {
+	func handle(
+		input: keyParser,
+		state inState: InputState,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		let charCode: UniChar = input.charCode
+		var state = inState  // Turn this incoming constant into variable.
+		let inputText: String = input.inputText ?? ""
+		let emptyState = InputState.Empty()
+
+		// Ignore the input if its inputText is empty.
+		// Reason: such inputs may be functional key combinations.
+
+		if (inputText).isEmpty {
+			return false
+		}
+
+		// Ignore the input if the composing buffer is empty with no reading
+		// and there is some function key combination.
+		let isFunctionKey: Bool =
+			input.isControlHotKey || (input.isCommandHold || input.isOptionHotKey || input.isNumericPad)
+		if !(state is InputState.NotEmpty) && !(state is InputState.AssociatedPhrases) && isFunctionKey {
+			return false
+		}
+
+		// MARK: Caps Lock processing.
+		// If Caps Lock is ON, temporarily disable bopomofo.
+		// Note: Alphanumerical mode processing.
+		if input.isBackSpace || input.isEnter || input.isAbsorbedArrowKey || input.isExtraChooseCandidateKey
+			|| input.isExtraChooseCandidateKeyReverse || input.isCursorForward || input.isCursorBackward
+		{
+			// Do nothing if backspace is pressed -- we ignore the key
+		} else if input.isCapsLockOn {
+			// Process all possible combination, we hope.
+			clear()
+			stateCallback(emptyState)
+
+			// When shift is pressed, don't do further processing...
+			// ...since it outputs capital letter anyway.
+			if input.isShiftHold {
+				return false
+			}
+
+			// If ASCII but not printable, don't use insertText:replacementRange:
+			// Certain apps don't handle non-ASCII char insertions.
+			if charCode < 0x80 && !isPrintable(charCode) {
+				return false
+			}
+
+			// Commit the entire input buffer.
+			let committingState = InputState.Committing(poppedText: inputText.lowercased())
+			stateCallback(committingState)
+			stateCallback(emptyState)
+
+			return true
+		}
+
+		// MARK: Numeric Pad Processing.
+		if input.isNumericPad {
+			if !input.isLeft && !input.isRight && !input.isDown
+				&& !input.isUp && !input.isSpace && isPrintable(charCode)
+			{
+				clear()
+				stateCallback(emptyState)
+				let committing = InputState.Committing(poppedText: inputText.lowercased())
+				stateCallback(committing)
+				stateCallback(emptyState)
+				return true
+			}
+		}
+
+		// MARK: Handle Candidates.
+		if state is InputState.ChoosingCandidate {
+			return _handleCandidateState(
+				state, input: input, stateCallback: stateCallback, errorCallback: errorCallback)
+		}
+
+		// MARK: Handle Associated Phrases.
+		if state is InputState.AssociatedPhrases {
+			let result = _handleCandidateState(
+				state, input: input, stateCallback: stateCallback, errorCallback: errorCallback)
+			if result {
+				return true
+			} else {
+				stateCallback(emptyState)
+			}
+		}
+
+		// MARK: Handle Marking.
+		if state is InputState.Marking {
+			let marking = state as! InputState.Marking
+
+			if _handleMarkingState(
+				state as! InputState.Marking, input: input, stateCallback: stateCallback,
+				errorCallback: errorCallback)
+			{
+				return true
+			}
+
+			state = marking.convertToInputting()
+			stateCallback(state)
+		}
+
+		// MARK: Handle BPMF Keys.
+		var composeReading: Bool = false
+		let skipPhoneticHandling = input.isReservedKey || input.isControlHold || input.isOptionHold
+
+		// See if Phonetic reading is valid.
+		if !skipPhoneticHandling && chkKeyValidity(charCode) {
+			combinePhoneticReadingBufferKey(charCode)
+
+			// If we have a tone marker, we have to insert the reading to the
+			// builder in other words, if we don't have a tone marker, we just
+			// update the composing buffer.
+			composeReading = checkWhetherToneMarkerConfirmsPhoneticReadingBuffer()
+			if !composeReading {
+				let inputting = buildInputtingState()
+				stateCallback(inputting)
+				return true
+			}
+
+		}
+
+		// See if we have composition if Enter/Space is hit and buffer is not empty.
+		// We use "|=" conditioning so that the tone marker key is also taken into account.
+		// However, Swift does not support "|=".
+		composeReading = composeReading || (!isPhoneticReadingBufferEmpty() && (input.isSpace || input.isEnter))
+		if composeReading {
+			let reading = getSyllableCompositionFromPhoneticReadingBuffer()
+
+			if !ifLangModelHasUnigrams(forKey: reading) {
+				IME.prtDebugIntel("B49C0979")
+				errorCallback()
+				let inputting = buildInputtingState()
+				stateCallback(inputting)
+				return true
+			}
+
+			// ... and insert it into the lattice grid...
+			insertReadingToBuilder(atCursor: reading)
+
+			// ... then walk the lattice grid...
+			let poppedText = _popOverflowComposingTextAndWalk()
+
+			// ... get and tweak override model suggestion if possible...
+			dealWithOverrideModelSuggestions()
+
+			// ... then update the text.
+			clearPhoneticReadingBuffer()
+
+			let inputting = buildInputtingState()
+			inputting.poppedText = poppedText
+			stateCallback(inputting)
+
+			if mgrPrefs.useSCPCTypingMode {
+				let choosingCandidates: InputState.ChoosingCandidate = _buildCandidateState(
+					inputting,
+					useVerticalMode: input.useVerticalMode)
+				if choosingCandidates.candidates.count == 1 {
+					clear()
+					let text: String = choosingCandidates.candidates.first ?? ""
+					let committing = InputState.Committing(poppedText: text)
+					stateCallback(committing)
+
+					if !mgrPrefs.associatedPhrasesEnabled {
+						stateCallback(emptyState)
+					} else {
+						let associatedPhrases =
+							buildAssociatePhraseState(
+								withKey: text,
+								useVerticalMode: input.useVerticalMode) as? InputState.AssociatedPhrases
+						if let associatedPhrases = associatedPhrases {
+							stateCallback(associatedPhrases)
+						} else {
+							stateCallback(emptyState)
+						}
+					}
+				} else {
+					stateCallback(choosingCandidates)
+				}
+			}
+			return true
+		}
+
+		// MARK: Calling candidate window using Space or Down or PageUp / PageDn.
+
+		if isPhoneticReadingBufferEmpty() && (state is InputState.NotEmpty)
+			&& (input.isExtraChooseCandidateKey || input.isExtraChooseCandidateKeyReverse || input.isSpace
+				|| input.isPageDown || input.isPageUp || input.isTab
+				|| (input.useVerticalMode && (input.isVerticalModeOnlyChooseCandidateKey)))
+		{
+			if input.isSpace {
+				// If the Space key is NOT set to be a selection key
+				if input.isShiftHold || !mgrPrefs.chooseCandidateUsingSpace {
+					if getBuilderCursorIndex() >= getBuilderLength() {
+						let composingBuffer = (state as! InputState.NotEmpty).composingBuffer
+						if (composingBuffer.count) != 0 {
+							let committing = InputState.Committing(poppedText: composingBuffer)
+							stateCallback(committing)
+						}
+						clear()
+						let committing = InputState.Committing(poppedText: " ")
+						stateCallback(committing)
+						let empty = InputState.Empty()
+						stateCallback(empty)
+					} else if ifLangModelHasUnigrams(forKey: " ") {
+						insertReadingToBuilder(atCursor: " ")
+						let poppedText = _popOverflowComposingTextAndWalk()
+						let inputting = buildInputtingState()
+						inputting.poppedText = poppedText
+						stateCallback(inputting)
+					}
+					return true
+				}
+			}
+			let choosingCandidates = _buildCandidateState(
+				state as! InputState.NotEmpty,
+				useVerticalMode: input.useVerticalMode)
+			stateCallback(choosingCandidates)
+			return true
+		}
+
+		// MARK: -
+
+		// MARK: Esc
+		if input.isESC { return _handleEscWithState(state, stateCallback: stateCallback, errorCallback: errorCallback) }
+
+		// MARK: Cursor backward
+		if input.isCursorBackward || input.emacsKey == vChewingEmacsKey.backward {
+			return _handleBackwardWithState(
+				state,
+				input: input,
+				stateCallback: stateCallback,
+				errorCallback: errorCallback)
+		}
+
+		// MARK: Cursor forward
+		if input.isCursorForward || input.emacsKey == vChewingEmacsKey.forward {
+			return _handleForwardWithState(
+				state, input: input, stateCallback: stateCallback, errorCallback: errorCallback)
+		}
+
+		// MARK: Home
+		if input.isHome || input.emacsKey == vChewingEmacsKey.home {
+			return _handleHomeWithState(state, stateCallback: stateCallback, errorCallback: errorCallback)
+		}
+
+		// MARK: End
+		if input.isEnd || input.emacsKey == vChewingEmacsKey.end {
+			return _handleEndWithState(state, stateCallback: stateCallback, errorCallback: errorCallback)
+		}
+
+		// MARK: Ctrl+PgLf or Shift+PgLf
+		if (input.isControlHold || input.isShiftHold) && (input.isOptionHold && input.isLeft) {
+			return _handleHomeWithState(state, stateCallback: stateCallback, errorCallback: errorCallback)
+		}
+
+		// MARK: Ctrl+PgRt or Shift+PgRt
+		if (input.isControlHold || input.isShiftHold) && (input.isOptionHold && input.isRight) {
+			return _handleEndWithState(state, stateCallback: stateCallback, errorCallback: errorCallback)
+		}
+
+		// MARK: AbsorbedArrowKey
+		if input.isAbsorbedArrowKey || input.isExtraChooseCandidateKey || input.isExtraChooseCandidateKeyReverse {
+			return _handleAbsorbedArrowKeyWithState(state, stateCallback: stateCallback, errorCallback: errorCallback)
+		}
+
+		// MARK: Backspace
+		if input.isBackSpace {
+			return _handleBackspaceWithState(state, stateCallback: stateCallback, errorCallback: errorCallback)
+		}
+
+		// MARK: Delete
+		if input.isDelete || input.emacsKey == vChewingEmacsKey.delete {
+			return _handleDeleteWithState(state, stateCallback: stateCallback, errorCallback: errorCallback)
+		}
+
+		// MARK: Enter
+		if input.isEnter {
+			return (input.isCommandHold && input.isControlHold)
+				? _handleCtrlCommandEnterWithState(state, stateCallback: stateCallback, errorCallback: errorCallback)
+				: _handleEnterWithState(state, stateCallback: stateCallback, errorCallback: errorCallback)
+		}
+
+		// MARK: -
+
+		// MARK: Punctuation list
+		if input.isSymbolMenuPhysicalKey && !input.isShiftHold {
+			if !input.isOptionHold {
+				if ifLangModelHasUnigrams(forKey: "_punctuation_list") {
+					if isPhoneticReadingBufferEmpty() {
+						insertReadingToBuilder(atCursor: "_punctuation_list")
+						let poppedText: String! = _popOverflowComposingTextAndWalk()
+						let inputting = buildInputtingState()
+						inputting.poppedText = poppedText
+						stateCallback(inputting)
+						let choosingCandidate =
+							_buildCandidateState(inputting, useVerticalMode: input.useVerticalMode)
+						stateCallback(choosingCandidate)
+					} else {  // If there is still unfinished bpmf reading, ignore the punctuation
+						IME.prtDebugIntel("17446655")
+						errorCallback()
+					}
+					return true
+				}
+			} else {
+				// 得在這裡先 commit buffer，不然會導致「在摁 ESC 離開符號選單時會重複輸入上一次的組字區的內容」的不當行為。
+				// 於是這裡用「模擬一次 Enter 鍵的操作」使其代為執行這個 commit buffer 的動作。
+				// 這裡不需要該函數所傳回的 bool 結果，所以用「_ =」解消掉。
+				_ = _handleEnterWithState(state, stateCallback: stateCallback, errorCallback: errorCallback)
+				let root: SymbolNode! = SymbolNode.root
+				let symbolState =
+					InputState.SymbolTable(node: root, useVerticalMode: input.useVerticalMode)
+				stateCallback(symbolState)
+				return true
+			}
+		}
+
+		// MARK: Punctuation
+		// if nothing is matched, see if it's a punctuation key for current layout.
+
+		var punctuationNamePrefix = ""
+
+		if input.isOptionHold {
+			punctuationNamePrefix = "_alt_punctuation_"
+		} else if input.isControlHold {
+			punctuationNamePrefix = "_ctrl_punctuation_"
+		} else if mgrPrefs.halfWidthPunctuationEnabled {
+			punctuationNamePrefix = "_half_punctuation_"
+		} else {
+			punctuationNamePrefix = "_punctuation_"
+		}
+
+		let parser = getCurrentMandarinParser()
+		let arrCustomPunctuations: [String] = [
+			punctuationNamePrefix, parser, String(format: "%c", CChar(charCode)),
+		]
+		let customPunctuation: String = arrCustomPunctuations.joined(separator: "")
+		if _handlePunctuation(
+			customPunctuation,
+			state: state,
+			usingVerticalMode: input.useVerticalMode,
+			stateCallback: stateCallback,
+			errorCallback: errorCallback)
+		{
+			return true
+		}
+
+		// if nothing is matched, see if it's a punctuation key.
+		let arrPunctuations: [String] = [punctuationNamePrefix, String(format: "%c", CChar(charCode))]
+		let punctuation: String = arrPunctuations.joined(separator: "")
+
+		if _handlePunctuation(
+			punctuation,
+			state: state,
+			usingVerticalMode: input.useVerticalMode,
+			stateCallback: stateCallback,
+			errorCallback: errorCallback)
+		{
+			return true
+		}
+
+		// 這裡不使用小麥注音 2.2 版的組字區處理方式，而是直接由詞庫負責。
+		if input.isUpperCaseASCIILetterKey {
+			let letter: String! = String(format: "%@%c", "_letter_", CChar(charCode))
+			if _handlePunctuation(
+				letter,
+				state: state,
+				usingVerticalMode: input.useVerticalMode,
+				stateCallback: stateCallback,
+				errorCallback: errorCallback)
+			{
+				return true
+			}
+		}
+
+		// MARK: - Still Nothing.
+		// Still nothing? Then we update the composing buffer.
+		// Note that some app has strange behavior if we don't do this,
+		// "thinking" that the key is not actually consumed.
+		// 砍掉這一段會導致「F1-F12 按鍵干擾組字區」的問題。
+		// 暫時只能先恢復這段，且補上偵錯彙報機制，方便今後排查故障。
+		if (state is InputState.NotEmpty) || !isPhoneticReadingBufferEmpty() {
+			IME.prtDebugIntel(
+				"Blocked data: charCode: \(charCode), keyCode: \(input.keyCode)")
+			IME.prtDebugIntel("A9BFF20E")
+			errorCallback()
+			stateCallback(state)
+			return true
+		}
+
+		return false
+	}
+}
--- a/Source/Modules/ControllerModules/KeyHandler_Misc.swift
+++ b/Source/Modules/ControllerModules/KeyHandler_Misc.swift
@ -0,0 +1,48 @@
+// Copyright (c) 2021 and onwards The vChewing Project (MIT-NTL License).
+// Refactored from the ObjCpp-version of this class by:
+// (c) 2011 and onwards The OpenVanilla Project (MIT License).
+/*
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+1. The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+2. 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 above.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+import Cocoa
+
+// MARK: - § Misc functions.
+@objc extension KeyHandler {
+
+	func getCurrentMandarinParser() -> String {
+		return (mgrPrefs.mandarinParserName + "_")
+	}
+
+	func _actualCandidateCursorIndex() -> Int {
+		var cursorIndex = getBuilderCursorIndex()
+		// MS Phonetics IME style, phrase is *after* the cursor.
+		// (i.e. the cursor is always *before* the phrase.)
+		if (mgrPrefs.selectPhraseAfterCursorAsCandidate
+			&& (cursorIndex < getBuilderLength()))
+			|| cursorIndex == 0
+		{
+			cursorIndex += 1
+		}
+		return cursorIndex
+	}
+}
--- a/Source/Modules/ControllerModules/KeyHandler_States.swift
+++ b/Source/Modules/ControllerModules/KeyHandler_States.swift
@ -0,0 +1,535 @@
+// Copyright (c) 2021 and onwards The vChewing Project (MIT-NTL License).
+// Refactored from the ObjCpp-version of this class by:
+// (c) 2011 and onwards The OpenVanilla Project (MIT License).
+/*
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+1. The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+2. 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 above.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+import Cocoa
+
+// MARK: - § State managements.
+@objc extension KeyHandler {
+
+	// MARK: - 構築狀態（State Building）
+	func buildInputtingState() -> InputState.Inputting {
+		// 觸發資料封裝更新，否則下文拿到的數據會是錯的。
+		packageBufferStateMaterials()
+		// 獲取封裝好的資料
+		let composedText = getComposedText()
+		let packagedCursorIndex = UInt(getPackagedCursorIndex())
+		let resultOfBefore = getStrLocationResult(isAfter: false)
+		let resultOfAfter = getStrLocationResult(isAfter: true)
+
+		// 初期化狀態
+		let newState = InputState.Inputting(composingBuffer: composedText, cursorIndex: packagedCursorIndex)
+
+		// 組建提示文本
+		var tooltip = ""
+		if (resultOfBefore == "") && (resultOfAfter != "") {
+			tooltip = String(format: NSLocalizedString("Cursor is after \"%@\".", comment: ""), resultOfAfter)
+		}
+		if (resultOfBefore != "") && (resultOfAfter == "") {
+			tooltip = String(format: NSLocalizedString("Cursor is before \"%@\".", comment: ""), resultOfBefore)
+		}
+		if (resultOfBefore != "") && (resultOfAfter != "") {
+			tooltip = String(
+				format: NSLocalizedString("Cursor is between \"%@\" and \"%@\".", comment: ""),
+				resultOfAfter, resultOfBefore)
+		}
+
+		// 給新狀態安插配置好的提示文本、且送出新狀態
+		newState.tooltip = tooltip
+		return newState
+	}
+
+	// MARK: - 用以生成候選詞數組
+	func _buildCandidateState(
+		_ currentState: InputState.NotEmpty,
+		useVerticalMode: Bool
+	) -> InputState.ChoosingCandidate {
+		let candidatesArray = getCandidatesArray()
+
+		let state = InputState.ChoosingCandidate(
+			composingBuffer: currentState.composingBuffer,
+			cursorIndex: currentState.cursorIndex,
+			candidates: candidatesArray,
+			useVerticalMode: useVerticalMode)
+		return state
+	}
+
+	// MARK: - 用以處理就地新增自訂語彙時的行為
+	func _handleMarkingState(
+		_ state: InputState.Marking,
+		input: keyParser,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+
+		if input.isESC {
+			let inputting = buildInputtingState()
+			stateCallback(inputting)
+			return true
+		}
+
+		// Enter
+		if input.isEnter {
+			if let keyHandlerDelegate = delegate {
+				if !keyHandlerDelegate.keyHandler(self, didRequestWriteUserPhraseWith: state) {
+					IME.prtDebugIntel("5B69CC8D")
+					errorCallback()
+					return true
+				}
+			}
+
+			let inputting = buildInputtingState()
+			stateCallback(inputting)
+			return true
+		}
+
+		// Shift + Left
+		if (input.isCursorBackward || input.emacsKey == vChewingEmacsKey.backward) && (input.isShiftHold) {
+			var index = state.markerIndex
+			if index > 0 {
+				index = UInt((state.composingBuffer as NSString).previousUtf16Position(for: Int(index)))
+				let marking = InputState.Marking(
+					composingBuffer: state.composingBuffer,
+					cursorIndex: state.cursorIndex,
+					markerIndex: index,
+					readings: state.readings)
+				marking.tooltipForInputting = state.tooltipForInputting
+
+				if marking.markedRange.length == 0 {
+					let inputting = marking.convertToInputting()
+					stateCallback(inputting)
+				} else {
+					stateCallback(marking)
+				}
+			} else {
+				IME.prtDebugIntel("1149908D")
+				errorCallback()
+				stateCallback(state)
+			}
+			return true
+		}
+
+		// Shift + Right
+		if (input.isCursorForward || input.emacsKey == vChewingEmacsKey.forward) && (input.isShiftHold) {
+			var index = state.markerIndex
+			// 這裡繼續用 NSString 是為了與 Zonble 之前引入的 NSStringUtils 相容。
+			// 不然的話，這行判斷會失敗、引發「9B51408D」錯誤。
+			if index < ((state.composingBuffer as NSString).length) {
+				index = UInt((state.composingBuffer as NSString).nextUtf16Position(for: Int(index)))
+				let marking = InputState.Marking(
+					composingBuffer: state.composingBuffer,
+					cursorIndex: state.cursorIndex,
+					markerIndex: index,
+					readings: state.readings)
+				marking.tooltipForInputting = state.tooltipForInputting
+				if marking.markedRange.length == 0 {
+					let inputting = marking.convertToInputting()
+					stateCallback(inputting)
+				} else {
+					stateCallback(marking)
+				}
+			} else {
+				IME.prtDebugIntel("9B51408D")
+				errorCallback()
+				stateCallback(state)
+			}
+			return true
+		}
+		return false
+	}
+
+	// MARK: - 標點輸入處理
+	func _handlePunctuation(
+		_ customPunctuation: String,
+		state: InputState,
+		usingVerticalMode useVerticalMode: Bool,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		if !ifLangModelHasUnigrams(forKey: customPunctuation) {
+			return false
+		}
+
+		if isPhoneticReadingBufferEmpty() {
+			insertReadingToBuilder(atCursor: customPunctuation)
+			let poppedText = _popOverflowComposingTextAndWalk()
+			let inputting = buildInputtingState()
+			inputting.poppedText = poppedText
+			stateCallback(inputting)
+
+			if mgrPrefs.useSCPCTypingMode && isPhoneticReadingBufferEmpty() {
+				let candidateState = _buildCandidateState(
+					inputting, useVerticalMode: useVerticalMode)
+				if candidateState.candidates.count == 1 {
+					clear()
+					if let strPoppedText: String = candidateState.candidates.first {
+						let committing =
+							InputState.Committing(poppedText: strPoppedText) as InputState.Committing
+						stateCallback(committing)
+						let empty = InputState.Empty()
+						stateCallback(empty)
+					} else {
+						stateCallback(candidateState)
+					}
+				} else {
+					stateCallback(candidateState)
+				}
+			}
+			return true
+		} else {
+			// If there is still unfinished bpmf reading, ignore the punctuation
+			IME.prtDebugIntel("A9B69908D")
+			errorCallback()
+			stateCallback(state)
+			return true
+		}
+	}
+
+	// MARK: - Enter 鍵處理
+	@discardableResult func _handleEnterWithState(
+		_ state: InputState,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		if !(state is InputState.Inputting) {
+			return false
+		}
+
+		clear()
+
+		let current = state as! InputState.Inputting
+		let composingBuffer = current.composingBuffer
+
+		let committing = InputState.Committing(poppedText: composingBuffer)
+		stateCallback(committing)
+		let empty = InputState.Empty()
+		stateCallback(empty)
+		return true
+	}
+
+	// MARK: - CMD+Enter 鍵處理
+	func _handleCtrlCommandEnterWithState(
+		_ state: InputState,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		if !(state is InputState.Inputting) {
+			return false
+		}
+
+		let readings: [String] = _currentReadings()
+		let composingBuffer =
+			(IME.areWeUsingOurOwnPhraseEditor)
+			? readings.joined(separator: "-")
+			: readings.joined(separator: " ")
+
+		clear()
+
+		let committing = InputState.Committing(poppedText: composingBuffer)
+		stateCallback(committing)
+		let empty = InputState.Empty()
+		stateCallback(empty)
+		return true
+	}
+
+	// MARK: - 處理 Backspace (macOS Delete) 按鍵行為
+	func _handleBackspaceWithState(
+		_ state: InputState,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		if !(state is InputState.Inputting) {
+			return false
+		}
+
+		if isPhoneticReadingBufferEmpty() {
+			if getBuilderCursorIndex() >= 0 {
+				deleteBuilderReadingInFrontOfCursor()
+				_walk()
+			} else {
+				IME.prtDebugIntel("9D69908D")
+				errorCallback()
+				stateCallback(state)
+				return true
+			}
+		} else {
+			doBackSpaceToPhoneticReadingBuffer()
+		}
+
+		if isPhoneticReadingBufferEmpty() && (getBuilderLength() == 0) {
+			let empty = InputState.EmptyIgnoringPreviousState()
+			stateCallback(empty)
+		} else {
+			let inputting = buildInputtingState()
+			stateCallback(inputting)
+		}
+		return true
+	}
+
+	// MARK: - 處理 PC Delete (macOS Fn+BackSpace) 按鍵行為
+	func _handleDeleteWithState(
+		_ state: InputState,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		if !(state is InputState.Inputting) {
+			return false
+		}
+
+		if isPhoneticReadingBufferEmpty() {
+			if getBuilderCursorIndex() != getBuilderLength() {
+				deleteBuilderReadingAfterCursor()
+				_walk()
+				let inputting = buildInputtingState()
+				if inputting.composingBuffer.count == 0 {
+					let empty = InputState.EmptyIgnoringPreviousState()
+					stateCallback(empty)
+				} else {
+					stateCallback(inputting)
+				}
+			} else {
+				IME.prtDebugIntel("9B69938D")
+				errorCallback()
+				stateCallback(state)
+			}
+		} else {
+			IME.prtDebugIntel("9C69908D")
+			errorCallback()
+			stateCallback(state)
+		}
+
+		return true
+	}
+
+	// MARK: - 處理與當前文字輸入排版前後方向呈 90 度的那兩個方向鍵的按鍵行為
+	func _handleAbsorbedArrowKeyWithState(
+		_ state: InputState,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		if !(state is InputState.Inputting) {
+			return false
+		}
+		if !isPhoneticReadingBufferEmpty() {
+			IME.prtDebugIntel("9B6F908D")
+			errorCallback()
+		}
+		stateCallback(state)
+		return true
+	}
+
+	// MARK: - 處理 Home 鍵行為
+	func _handleHomeWithState(
+		_ state: InputState,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		if !(state is InputState.Inputting) {
+			return false
+		}
+
+		if !isPhoneticReadingBufferEmpty() {
+			IME.prtDebugIntel("ABC44080")
+			errorCallback()
+			stateCallback(state)
+			return true
+		}
+
+		if getBuilderCursorIndex() != 0 {
+			setBuilderCursorIndex(0)
+			let inputting = buildInputtingState()
+			stateCallback(inputting)
+		} else {
+			IME.prtDebugIntel("66D97F90")
+			errorCallback()
+			stateCallback(state)
+		}
+
+		return true
+	}
+
+	// MARK: - 處理 End 鍵行為
+	func _handleEndWithState(
+		_ state: InputState,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		if !(state is InputState.Inputting) {
+			return false
+		}
+
+		if !isPhoneticReadingBufferEmpty() {
+			IME.prtDebugIntel("9B69908D")
+			errorCallback()
+			stateCallback(state)
+			return true
+		}
+
+		if getBuilderCursorIndex() != getBuilderLength() {
+			setBuilderCursorIndex(getBuilderLength())
+			let inputting = buildInputtingState()
+			stateCallback(inputting)
+		} else {
+			IME.prtDebugIntel("9B69908E")
+			errorCallback()
+			stateCallback(state)
+		}
+
+		return true
+	}
+
+	// MARK: - 處理 Esc 鍵行為
+	func _handleEscWithState(
+		_ state: InputState,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+		if !(state is InputState.Inputting) { return false }
+
+		let escToClearInputBufferEnabled: Bool = mgrPrefs.escToCleanInputBuffer
+
+		if escToClearInputBufferEnabled {
+			// If the option is enabled, we clear everything in the buffer.
+			// This includes walked nodes and the reading. Note that this convention
+			// is by default in macOS 10.0-10.5 built-in Panasonic Hanin and later macOS Zhuyin.
+			// Some Windows users hate this design, hence the option here to disable it.
+			clear()
+			let empty = InputState.EmptyIgnoringPreviousState()
+			stateCallback(empty)
+		} else {
+			// If reading is not empty, we cancel the reading.
+			if !isPhoneticReadingBufferEmpty() {
+				clearPhoneticReadingBuffer()
+				if getBuilderLength() == 0 {
+					let empty = InputState.Empty()
+					stateCallback(empty)
+				} else {
+					let inputting = buildInputtingState()
+					stateCallback(inputting)
+				}
+			}
+		}
+		return true
+	}
+	// MARK: - 處理向前方向鍵的行為
+	func _handleForwardWithState(
+		_ state: InputState,
+		input: keyParser,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+
+		if !(state is InputState.Inputting) { return false }
+
+		if !isPhoneticReadingBufferEmpty() {
+			IME.prtDebugIntel("B3BA5257")
+			errorCallback()
+			stateCallback(state)
+			return true
+		}
+
+		let currentState = state as! InputState.Inputting
+
+		if input.isShiftHold {
+			// Shift + Right
+			if currentState.cursorIndex < (currentState.composingBuffer as NSString).length {
+				let nextPosition = (currentState.composingBuffer as NSString).nextUtf16Position(
+					for: Int(currentState.cursorIndex))
+				let marking: InputState.Marking! = InputState.Marking(
+					composingBuffer: currentState.composingBuffer,
+					cursorIndex: currentState.cursorIndex,
+					markerIndex: UInt(nextPosition),
+					readings: _currentReadings())
+				marking.tooltipForInputting = currentState.tooltip
+				stateCallback(marking)
+			} else {
+				IME.prtDebugIntel("BB7F6DB9")
+				errorCallback()
+				stateCallback(state)
+			}
+		} else {
+			if getBuilderCursorIndex() < getBuilderLength() {
+				setBuilderCursorIndex(getBuilderCursorIndex() + 1)
+				let inputting = buildInputtingState()
+				stateCallback(inputting)
+			} else {
+				IME.prtDebugIntel("A96AAD58")
+				errorCallback()
+				stateCallback(state)
+			}
+		}
+		return true
+	}
+
+	// MARK: - 處理向後方向鍵的行為
+	func _handleBackwardWithState(
+		_ state: InputState,
+		input: keyParser,
+		stateCallback: @escaping (InputState) -> Void,
+		errorCallback: @escaping () -> Void
+	) -> Bool {
+
+		if !(state is InputState.Inputting) { return false }
+
+		if !isPhoneticReadingBufferEmpty() {
+			IME.prtDebugIntel("6ED95318")
+			errorCallback()
+			stateCallback(state)
+			return true
+		}
+
+		let currentState = state as! InputState.Inputting
+
+		if input.isShiftHold {
+			// Shift + left
+			if currentState.cursorIndex > 0 {
+				let previousPosition = (currentState.composingBuffer as NSString).previousUtf16Position(
+					for: Int(currentState.cursorIndex))
+				let marking: InputState.Marking! = InputState.Marking(
+					composingBuffer: currentState.composingBuffer,
+					cursorIndex: currentState.cursorIndex,
+					markerIndex: UInt(previousPosition),
+					readings: _currentReadings())
+				marking.tooltipForInputting = currentState.tooltip
+				stateCallback(marking)
+			} else {
+				IME.prtDebugIntel("D326DEA3")
+				errorCallback()
+				stateCallback(state)
+			}
+		} else {
+			if getBuilderCursorIndex() > 0 {
+				setBuilderCursorIndex(getBuilderCursorIndex() - 1)
+				let inputting = buildInputtingState()
+				stateCallback(inputting)
+			} else {
+				IME.prtDebugIntel("7045E6F3")
+				errorCallback()
+				stateCallback(state)
+			}
+		}
+		return true
+	}
+}
--- a/Source/Modules/IMEModules/ctlInputMethod.swift
+++ b/Source/Modules/IMEModules/ctlInputMethod.swift
@ -60,7 +60,7 @@ class ctlInputMethod: IMKInputController {
 	// 所以才需要「currentKeyHandler」這個假 keyHandler。
 	// 這個「currentKeyHandler」僅用來讓其他模組知道當前的輸入模式是什麼模式，除此之外別無屌用。
 	static var currentKeyHandler: KeyHandler = KeyHandler()
-	@objc static var currentInputMode = ""
+	@objc static var currentInputMode = mgrPrefs.mostRecentInputMode

 	// MARK: - Keyboard Layout Specifier

@ -75,6 +75,9 @@ class ctlInputMethod: IMKInputController {
 	override init!(server: IMKServer!, delegate: Any!, client inputClient: Any!) {
 		super.init(server: server, delegate: delegate, client: inputClient)
 		keyHandler.delegate = self
+		// 下述兩行很有必要，否則輸入法會在手動重啟之後無法立刻生效。
+		activateServer(inputClient)
+		resetKeyHandler()
 	}

 	// MARK: - KeyHandler Reset Command
@ -95,7 +98,7 @@ class ctlInputMethod: IMKInputController {
 		currentClient = client

 		keyHandler.clear()
-		keyHandler.syncWithPreferences()
+		keyHandler.ensurePhoneticParser()
 		if let bundleCheckID = (client as? IMKTextInput)?.bundleIdentifier() {
 			if bundleCheckID != Bundle.main.bundleIdentifier {
 				// Override the keyboard layout to the basic one.
@ -598,9 +601,7 @@ extension ctlInputMethod: ctlCandidateDelegate {
 			let selectedValue = state.candidates[Int(index)]
 			keyHandler.fixNode(value: selectedValue)

-			guard let inputting = keyHandler.buildInputtingState() as? InputState.Inputting else {
-				return
-			}
+			let inputting = keyHandler.buildInputtingState()

 			if mgrPrefs.useSCPCTypingMode {
 				keyHandler.clear()
--- a/Source/Modules/IMEModules/ctlInputMethod_Menu.swift
+++ b/Source/Modules/IMEModules/ctlInputMethod_Menu.swift
@ -261,6 +261,7 @@ extension ctlInputMethod {
 	}

 	@objc func selfTerminate(_ sender: Any?) {
+		NSApp.activate(ignoringOtherApps: true)
 		NSApp.terminate(nil)
 	}

--- a/Source/Modules/IMEModules/mgrPrefs.swift
+++ b/Source/Modules/IMEModules/mgrPrefs.swift
@ -28,6 +28,7 @@ import Cocoa

 struct UserDef {
 	static let kIsDebugModeEnabled = "_DebugMode"
+	static let kMostRecentInputMode = "MostRecentInputMode"
 	static let kUserDataFolderSpecified = "UserDataFolderSpecified"
 	static let kCheckUpdateAutomatically = "CheckUpdateAutomatically"
 	static let kMandarinParser = "MandarinParser"
@ -204,6 +205,7 @@ public class mgrPrefs: NSObject {
 	static var allKeys: [String] {
 		[
 			UserDef.kIsDebugModeEnabled,
+			UserDef.kMostRecentInputMode,
 			UserDef.kUserDataFolderSpecified,
 			UserDef.kMandarinParser,
 			UserDef.kBasicKeyboardLayout,
@ -238,6 +240,7 @@ public class mgrPrefs: NSObject {
 	// MARK: - 既然 Preferences Module 的預設屬性不自動寫入 plist，那這邊就先寫入了。
 	@objc public static func setMissingDefaults() {
 		UserDefaults.standard.setDefault(mgrPrefs.isDebugModeEnabled, forKey: UserDef.kIsDebugModeEnabled)
+		UserDefaults.standard.setDefault(mgrPrefs.mostRecentInputMode, forKey: UserDef.kMostRecentInputMode)
 		UserDefaults.standard.setDefault(mgrPrefs.checkUpdateAutomatically, forKey: UserDef.kCheckUpdateAutomatically)
 		UserDefaults.standard.setDefault(
 			mgrPrefs.showPageButtonsInCandidateWindow, forKey: UserDef.kShowPageButtonsInCandidateWindow)
@ -271,6 +274,9 @@ public class mgrPrefs: NSObject {
 	@UserDefault(key: UserDef.kIsDebugModeEnabled, defaultValue: false)
 	@objc static var isDebugModeEnabled: Bool

+	@UserDefault(key: UserDef.kMostRecentInputMode, defaultValue: "")
+	@objc static var mostRecentInputMode: String
+
 	@UserDefault(key: UserDef.kCheckUpdateAutomatically, defaultValue: false)
 	@objc static var checkUpdateAutomatically: Bool

--- a/vChewing.xcodeproj/project.pbxproj
+++ b/vChewing.xcodeproj/project.pbxproj
@ -13,7 +13,9 @@
 		5B27AD6B27CB1F9B000ED75B /* data-zhuyinwen.txt in Resources */ = {isa = PBXBuildFile; fileRef = 5B27AD6927CB1F9B000ED75B /* data-zhuyinwen.txt */; };
 		5B2DB16F27AF6891006D874E /* data-chs.txt in Resources */ = {isa = PBXBuildFile; fileRef = 5B2DB16D27AF6891006D874E /* data-chs.txt */; };
 		5B2DB17027AF6891006D874E /* data-cht.txt in Resources */ = {isa = PBXBuildFile; fileRef = 5B2DB16E27AF6891006D874E /* data-cht.txt */; };
+		5B3133BF280B229700A4A505 /* KeyHandler_States.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5B3133BE280B229700A4A505 /* KeyHandler_States.swift */; };
 		5B5E535227EF261400C6AA1E /* IME.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5B5E535127EF261400C6AA1E /* IME.swift */; };
+		5B61B0CA280BEFD4002E3CFA /* KeyHandler_Misc.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5B61B0C9280BEFD4002E3CFA /* KeyHandler_Misc.swift */; };
 		5B62A32927AE77D100A19448 /* FSEventStreamHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5B62A32827AE77D100A19448 /* FSEventStreamHelper.swift */; };
 		5B62A32F27AE78B000A19448 /* CoreLM.mm in Sources */ = {isa = PBXBuildFile; fileRef = 5B62A32D27AE78B000A19448 /* CoreLM.mm */; };
 		5B62A33227AE792F00A19448 /* InputSourceHelper.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5B62A33127AE792F00A19448 /* InputSourceHelper.swift */; };
@ -29,7 +31,9 @@
 		5B707CE827D9F4590099EF99 /* OpenCCBridge.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5B707CE727D9F4590099EF99 /* OpenCCBridge.swift */; };
 		5B707CEC27D9F4870099EF99 /* OpenCC in Frameworks */ = {isa = PBXBuildFile; productRef = 5B707CEB27D9F4870099EF99 /* OpenCC */; };
 		5B73FB5E27B2BE1300E9BF49 /* InfoPlist.strings in Resources */ = {isa = PBXBuildFile; fileRef = 5B73FB6027B2BE1300E9BF49 /* InfoPlist.strings */; };
+		5B782EC4280C243C007276DE /* KeyHandler_HandleCandidate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5B782EC3280C243C007276DE /* KeyHandler_HandleCandidate.swift */; };
 		5B7BC4B027AFFBE800F66C24 /* frmPrefWindow.xib in Resources */ = {isa = PBXBuildFile; fileRef = 5B7BC4AE27AFFBE800F66C24 /* frmPrefWindow.xib */; };
+		5B7F225D2808501000DDD3CB /* KeyHandler_HandleInput.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5B7F225C2808501000DDD3CB /* KeyHandler_HandleInput.swift */; };
 		5BA9FD0F27FEDB6B002DE248 /* suiPrefPaneGeneral.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5BA9FD0A27FEDB6B002DE248 /* suiPrefPaneGeneral.swift */; };
 		5BA9FD1027FEDB6B002DE248 /* suiPrefPaneKeyboard.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5BA9FD0B27FEDB6B002DE248 /* suiPrefPaneKeyboard.swift */; };
 		5BA9FD1127FEDB6B002DE248 /* ctlPrefUI.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5BA9FD0C27FEDB6B002DE248 /* ctlPrefUI.swift */; };
@ -185,7 +189,9 @@
 		5B2DB16E27AF6891006D874E /* data-cht.txt */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; name = "data-cht.txt"; path = "Data/data-cht.txt"; sourceTree = "<group>"; };
 		5B2DB17127AF8771006D874E /* Makefile */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.make; name = Makefile; path = Data/Makefile; sourceTree = "<group>"; };
 		5B30F11227BA568800484E24 /* vChewingKeyLayout.bundle */ = {isa = PBXFileReference; lastKnownFileType = "wrapper.plug-in"; path = vChewingKeyLayout.bundle; sourceTree = "<group>"; };
+		5B3133BE280B229700A4A505 /* KeyHandler_States.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeyHandler_States.swift; sourceTree = "<group>"; };
 		5B5E535127EF261400C6AA1E /* IME.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = IME.swift; sourceTree = "<group>"; };
+		5B61B0C9280BEFD4002E3CFA /* KeyHandler_Misc.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeyHandler_Misc.swift; sourceTree = "<group>"; };
 		5B62A32627AE77BB00A19448 /* LMConsolidator.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = LMConsolidator.h; sourceTree = "<group>"; };
 		5B62A32727AE77BB00A19448 /* LMConsolidator.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = LMConsolidator.mm; sourceTree = "<group>"; };
 		5B62A32827AE77D100A19448 /* FSEventStreamHelper.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = FSEventStreamHelper.swift; sourceTree = "<group>"; };
@ -206,8 +212,10 @@
 		5B7111C727DEF9FF00444310 /* UserSymbolLM.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = UserSymbolLM.h; sourceTree = "<group>"; };
 		5B73FB5427B2BD6900E9BF49 /* PhraseEditor-Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; name = "PhraseEditor-Info.plist"; path = "UserPhraseEditor/PhraseEditor-Info.plist"; sourceTree = SOURCE_ROOT; };
 		5B73FB5F27B2BE1300E9BF49 /* en */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = en; path = en.lproj/InfoPlist.strings; sourceTree = "<group>"; };
+		5B782EC3280C243C007276DE /* KeyHandler_HandleCandidate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeyHandler_HandleCandidate.swift; sourceTree = "<group>"; };
 		5B7BC4AF27AFFBE800F66C24 /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.xib; name = Base; path = Base.lproj/frmPrefWindow.xib; sourceTree = "<group>"; };
 		5B7BC4B227AFFC0B00F66C24 /* en */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = en; path = en.lproj/frmPrefWindow.strings; sourceTree = "<group>"; };
+		5B7F225C2808501000DDD3CB /* KeyHandler_HandleInput.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = KeyHandler_HandleInput.swift; sourceTree = "<group>"; };
 		5B8F43ED27C9BC220069AC27 /* SymbolLM.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = SymbolLM.h; sourceTree = "<group>"; };
 		5BA9FD0A27FEDB6B002DE248 /* suiPrefPaneGeneral.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = suiPrefPaneGeneral.swift; sourceTree = "<group>"; };
 		5BA9FD0B27FEDB6B002DE248 /* suiPrefPaneKeyboard.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = suiPrefPaneKeyboard.swift; sourceTree = "<group>"; };
@ -324,7 +332,7 @@
 		D4E33D8927A838CF006DB1CF /* Base */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = Base; path = Base.lproj/Localizable.strings; sourceTree = "<group>"; };
 		D4E33D8E27A838F0006DB1CF /* Base */ = {isa = PBXFileReference; lastKnownFileType = text.plist.strings; name = Base; path = Base.lproj/InfoPlist.strings; sourceTree = "<group>"; };
 		D4E569DA27A34CC100AC2CEF /* KeyHandler.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = KeyHandler.h; sourceTree = "<group>"; };
-		D4E569DB27A34CC100AC2CEF /* KeyHandler.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = KeyHandler.mm; sourceTree = "<group>"; };
+		D4E569DB27A34CC100AC2CEF /* KeyHandler.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = KeyHandler.mm; sourceTree = "<group>"; usesTabs = 0; };
 		D4F0BBDE279AF1AF0071253C /* ArchiveUtil.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ArchiveUtil.swift; sourceTree = "<group>"; };
 		D4F0BBE0279AF8B30071253C /* AppDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
 		D4F0BBE2279B08900071253C /* Chronosphere.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = Chronosphere.h; sourceTree = "<group>"; };
@ -423,6 +431,10 @@
 				D461B791279DAC010070E734 /* InputState.swift */,
 				D4E569DA27A34CC100AC2CEF /* KeyHandler.h */,
 				D4E569DB27A34CC100AC2CEF /* KeyHandler.mm */,
+				5B7F225C2808501000DDD3CB /* KeyHandler_HandleInput.swift */,
+				5B782EC3280C243C007276DE /* KeyHandler_HandleCandidate.swift */,
+				5B61B0C9280BEFD4002E3CFA /* KeyHandler_Misc.swift */,
+				5B3133BE280B229700A4A505 /* KeyHandler_States.swift */,
 				D456576D279E4F7B00DF6BC9 /* KeyParser.swift */,
 				6ACC3D3E27914F2400F1B140 /* KeyValueBlobReader.cpp */,
 				6ACC3D3C27914AAB00F1B140 /* KeyValueBlobReader.h */,
@ -1061,6 +1073,7 @@
 				D427F76C278CA2B0004A2160 /* AppDelegate.swift in Sources */,
 				5BA9FD4527FEF3C9002DE248 /* ToolbarItemStyleViewController.swift in Sources */,
 				5BA9FD4127FEF3C8002DE248 /* PreferencesStyle.swift in Sources */,
+				5B7F225D2808501000DDD3CB /* KeyHandler_HandleInput.swift in Sources */,
 				5BA9FD1227FEDB6B002DE248 /* suiPrefPaneExperience.swift in Sources */,
 				6ACC3D442793701600F1B140 /* ParselessPhraseDB.cpp in Sources */,
 				D461B792279DAC010070E734 /* InputState.swift in Sources */,
@ -1076,6 +1089,7 @@
 				5BE78BE027B38804005EA1BE /* LMConsolidator.mm in Sources */,
 				D456576E279E4F7B00DF6BC9 /* KeyParser.swift in Sources */,
 				5BA9FD1027FEDB6B002DE248 /* suiPrefPaneKeyboard.swift in Sources */,
+				5B3133BF280B229700A4A505 /* KeyHandler_States.swift in Sources */,
 				5BA9FD4327FEF3C8002DE248 /* Preferences.swift in Sources */,
 				5BA9FD4427FEF3C8002DE248 /* SegmentedControlStyleViewController.swift in Sources */,
 				D47F7DCE278BFB57002F9DD7 /* ctlPrefWindow.swift in Sources */,
@ -1090,6 +1104,7 @@
 				D47F7DD3278C1263002F9DD7 /* UserOverrideModel.cpp in Sources */,
 				5B62A33627AE795800A19448 /* mgrPrefs.swift in Sources */,
 				5BAEFAD028012565001F42C9 /* mgrLangModel.swift in Sources */,
+				5B782EC4280C243C007276DE /* KeyHandler_HandleCandidate.swift in Sources */,
 				5B62A33827AE79CD00A19448 /* NSStringUtils.swift in Sources */,
 				5BA9FD0F27FEDB6B002DE248 /* suiPrefPaneGeneral.swift in Sources */,
 				5BA9FD4927FEF3C9002DE248 /* Section.swift in Sources */,
@ -1099,6 +1114,7 @@
 				5B5E535227EF261400C6AA1E /* IME.swift in Sources */,
 				5B62A34927AE7CD900A19448 /* TooltipController.swift in Sources */,
 				6A0D4F4515FC0EB100ABF4B3 /* Mandarin.cpp in Sources */,
+				5B61B0CA280BEFD4002E3CFA /* KeyHandler_Misc.swift in Sources */,
 				5B62A34827AE7CD900A19448 /* ctlCandidateVertical.swift in Sources */,
 				5BA9FD4027FEF3C8002DE248 /* Localization.swift in Sources */,
 				5BA9FD1327FEDB6B002DE248 /* suiPrefPaneDictionary.swift in Sources */,
@ -1434,7 +1450,6 @@
 					"$(OTHER_CFLAGS)",
 					"-fcxx-modules",
 				);
-				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
 			};
 			name = Debug;
 		};
@ -1475,8 +1490,6 @@
 					"$(OTHER_CFLAGS)",
 					"-fcxx-modules",
 				);
-				SWIFT_COMPILATION_MODE = wholemodule;
-				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
 			};
 			name = Release;
 		};