Merge branch 'dev_处理立刻清空和撤销删除' into dev_st

# Conflicts:
#	CustomKeyboard/Utils/KBBackspaceLongPressHandler.m
解决冲突

CustomKeyboard/KeyboardViewController.m

@@ -20,6 +20,7 @@
 #import "KBKeyboardSubscriptionView.h"
 #import "KBKeyboardSubscriptionProduct.h"
 #import "KBBackspaceUndoManager.h"
+#import "KBInputBufferManager.h"
 #import "KBSuggestionEngine.h"
 
 // 提前声明一个类别，使编译器在 static 回调中识别 kb_consumePendingShopSkin 方法。
@@ -64,6 +65,8 @@ static void KBSkinInstallNotificationCallback(CFNotificationCenterRef center,
 
 - (void)viewDidLoad {
     [super viewDidLoad];
+    // 撤销删除是“上一段删除操作”的临时状态；键盘被系统回收/重建或跨页面回来时应当清空，避免误显示。
+    [[KBBackspaceUndoManager shared] registerNonClearAction];
     [self setupUI];
     self.suggestionEngine = [KBSuggestionEngine shared];
     self.currentWord = @"";
@@ -92,7 +95,24 @@ static void KBSkinInstallNotificationCallback(CFNotificationCenterRef center,
 
 - (void)viewWillAppear:(BOOL)animated{
     [super viewWillAppear:animated];
+    // 进入/重新进入输入界面时，清理上一次会话残留的撤销状态与缓存，避免显示“撤销删除”但实际上已不可撤销。
+    [[KBBackspaceUndoManager shared] registerNonClearAction];
+    [[KBInputBufferManager shared] resetWithText:@""];
     [[KBLocalizationManager shared] reloadFromSharedStorageIfNeeded];
+    // 注意：微信/QQ 等宿主的 documentContext 可能是“截断窗口”，这里只更新 liveText，不要把它当作全文 manualSnapshot。
+    [[KBInputBufferManager shared] updateFromExternalContextBefore:self.textDocumentProxy.documentContextBeforeInput
+                                                             after:self.textDocumentProxy.documentContextAfterInput];
+}
+
+- (void)viewWillDisappear:(BOOL)animated {
+    [super viewWillDisappear:animated];
+    [[KBBackspaceUndoManager shared] registerNonClearAction];
+}
+
+- (void)textDidChange:(id<UITextInput>)textInput {
+    [super textDidChange:textInput];
+    [[KBInputBufferManager shared] updateFromExternalContextBefore:self.textDocumentProxy.documentContextBeforeInput
+                                                             after:self.textDocumentProxy.documentContextAfterInput];
 }
 
 
@@ -369,22 +389,27 @@ static void KBSkinInstallNotificationCallback(CFNotificationCenterRef center,
             NSString *text = key.output ?: key.title ?: @"";
             [self.textDocumentProxy insertText:text];
             [self kb_updateCurrentWordWithInsertedText:text];
+            [[KBInputBufferManager shared] appendText:text];
         } break;
         case KBKeyTypeBackspace:
-            [[KBBackspaceUndoManager shared] recordDeletionSnapshotBefore:self.textDocumentProxy.documentContextBeforeInput
+            [[KBInputBufferManager shared] refreshFromProxyIfPossible:self.textDocumentProxy];
+            [[KBInputBufferManager shared] prepareSnapshotForDeleteWithContextBefore:self.textDocumentProxy.documentContextBeforeInput
                                                                                after:self.textDocumentProxy.documentContextAfterInput];
-            [self.textDocumentProxy deleteBackward];
+            [[KBBackspaceUndoManager shared] captureAndDeleteBackwardFromProxy:self.textDocumentProxy count:1];
             [self kb_scheduleContextRefreshResetSuppression:NO];
+            [[KBInputBufferManager shared] applyHoldDeleteCount:1];
             break;
         case KBKeyTypeSpace:
             [[KBBackspaceUndoManager shared] registerNonClearAction];
             [self.textDocumentProxy insertText:@" "];
             [self kb_clearCurrentWord];
+            [[KBInputBufferManager shared] appendText:@" "];
             break;
         case KBKeyTypeReturn:
             [[KBBackspaceUndoManager shared] registerNonClearAction];
             [self.textDocumentProxy insertText:@"\n"];
             [self kb_clearCurrentWord];
+            [[KBInputBufferManager shared] appendText:@"\n"];
             break;
         case KBKeyTypeGlobe:
             [self advanceToNextInputMode]; break;
@@ -419,6 +444,7 @@ static void KBSkinInstallNotificationCallback(CFNotificationCenterRef center,
     [[KBBackspaceUndoManager shared] registerNonClearAction];
     [self.textDocumentProxy insertText:emoji];
     [self kb_clearCurrentWord];
+    [[KBInputBufferManager shared] appendText:emoji];
 }
 
 - (void)keyBoardMainViewDidTapUndo:(KBKeyBoardMainView *)keyBoardMainView {
@@ -432,6 +458,7 @@ static void KBSkinInstallNotificationCallback(CFNotificationCenterRef center,
 
 - (void)keyBoardMainView:(KBKeyBoardMainView *)keyBoardMainView didSelectSuggestion:(NSString *)suggestion {
     if (suggestion.length == 0) { return; }
+    [[KBBackspaceUndoManager shared] registerNonClearAction];
     NSString *current = self.currentWord ?: @"";
     if (current.length > 0) {
         for (NSUInteger i = 0; i < current.length; i++) {
@@ -443,6 +470,7 @@ static void KBSkinInstallNotificationCallback(CFNotificationCenterRef center,
     [self.suggestionEngine recordSelection:suggestion];
     self.suppressSuggestions = YES;
     [self.keyBoardMainView kb_setSuggestions:@[]];
+    [[KBInputBufferManager shared] replaceTailWithText:suggestion deleteCount:current.length];
 }
 
 // MARK: - KBFunctionViewDelegate

CustomKeyboard/Utils/KBBackspaceLongPressHandler.h

@@ -11,10 +11,10 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (instancetype)initWithContainerView:(UIView *)containerView;
 
-/// 配置删除按钮（包含长按删除；可选是否显示“立刻清空”提示）
+/// 配置删除按钮（包含长按删除；可选是否显示“上滑清空”提示）
 - (void)bindDeleteButton:(nullable UIView *)button showClearLabel:(BOOL)showClearLabel;
 
-/// 触发“立刻清空”逻辑（可用于功能面板的清空按钮）
+/// 触发“上滑清空”逻辑（可用于功能面板的清空按钮）
 - (void)performClearAction;
 
 @end

CustomKeyboard/Utils/KBBackspaceLongPressHandler.m

@@ -7,24 +7,25 @@
 #import "KBResponderUtils.h"
 #import "KBSkinManager.h"
 #import "KBBackspaceUndoManager.h"
+#import "KBInputBufferManager.h"
 
 static const NSTimeInterval kKBBackspaceLongPressMinDuration = 0.35;
 static const NSTimeInterval kKBBackspaceRepeatInterval = 0.06;
-static const NSTimeInterval kKBBackspaceChunkStartDelay = 1.0;
+static const NSTimeInterval kKBBackspaceChunkStartDelay = 0.6;
 static const NSTimeInterval kKBBackspaceChunkRepeatInterval = 0.1;
-static const NSTimeInterval kKBBackspaceChunkFastDelay = 1.4;
+static const NSTimeInterval kKBBackspaceChunkFastDelay = 1.2;
-static const NSInteger kKBBackspaceChunkSize = 6;
+static const NSInteger kKBBackspaceChunkSize = 8;
-static const NSInteger kKBBackspaceChunkSizeFast = 12;
+static const NSInteger kKBBackspaceChunkSizeFast = 16;
 static const CGFloat kKBBackspaceClearLabelCornerRadius = 8.0;
 static const CGFloat kKBBackspaceClearLabelHeight = 34;
 static const CGFloat kKBBackspaceClearLabelPaddingX = 10.0;
 static const CGFloat kKBBackspaceClearLabelTopGap = 6.0;
 static const CGFloat kKBBackspaceClearLabelHorizontalInset = 6.0;
-static const NSInteger kKBBackspaceClearBatchSize = 24;
+static const NSTimeInterval kKBBackspaceClearBatchInterval = 0.02;
-static const NSTimeInterval kKBBackspaceClearBatchInterval = 0.005;
 static const NSInteger kKBBackspaceClearMaxDeletes = 10000;
 static const NSInteger kKBBackspaceClearEmptyContextMaxRounds = 40;
 static const NSInteger kKBBackspaceClearMaxStep = 80;
+static const NSInteger kKBBackspaceClearDeletesPerTick = 10;
 
 typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
     KBBackspaceChunkClassUnknown = 0,
@@ -34,6 +35,12 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
     KBBackspaceChunkClassOther
 };
 
+typedef NS_ENUM(NSInteger, KBClearPhase) {
+    KBClearPhaseSkipWhitespace = 0,
+    KBClearPhaseSkipTrailingBoundary,
+    KBClearPhaseDeleteUntilBoundary
+};
+
 @interface KBBackspaceLongPressHandler ()
 @property (nonatomic, weak) UIView *containerView;
 @property (nonatomic, weak) UIView *backspaceButton;
@@ -50,6 +57,7 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
 @property (nonatomic, strong) UILabel *backspaceClearLabel;
 @property (nonatomic, copy) NSString *pendingClearBefore;
 @property (nonatomic, copy) NSString *pendingClearAfter;
+@property (nonatomic, assign) KBClearPhase backspaceClearPhase;
 @end
 
 @implementation KBBackspaceLongPressHandler
@@ -57,6 +65,7 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
 - (instancetype)initWithContainerView:(UIView *)containerView {
     if (self = [super init]) {
         _containerView = containerView;
+        _backspaceClearPhase = KBClearPhaseSkipWhitespace;
     }
     return self;
 }
@@ -103,9 +112,17 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
     }
     switch (gr.state) {
         case UIGestureRecognizerStateBegan: {
-            [self kb_captureDeletionSnapshotIfNeeded];
+            UIResponder *start = (UIResponder *)([self kb_hostView] ?: self.backspaceButton);
+            UIInputViewController *ivc = KBFindInputViewController(start);
+            if (ivc) {
+                id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
+                [[KBInputBufferManager shared] refreshFromProxyIfPossible:proxy];
+                [[KBInputBufferManager shared] prepareSnapshotForDeleteWithContextBefore:proxy.documentContextBeforeInput
+                                                                                   after:proxy.documentContextAfterInput];
+            }
             if (self.showClearLabelEnabled) {
                 [self kb_capturePendingClearSnapshotIfNeeded];
+                [[KBInputBufferManager shared] beginPendingClearSnapshot];
             }
             self.backspaceHoldToken += 1;
             NSUInteger token = self.backspaceHoldToken;
@@ -141,6 +158,7 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
     if (!ivc) { self.backspaceHoldActive = NO; return; }
     id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
     NSString *before = proxy.documentContextBeforeInput ?: @"";
+    if (before.length == 0) { before = [KBInputBufferManager shared].liveText ?: @""; }
     NSTimeInterval elapsed = [NSDate date].timeIntervalSinceReferenceDate - self.backspaceHoldStartTime;
     NSInteger deleteCount = 1;
     if (before.length > 0) {
@@ -152,9 +170,8 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
             [self kb_showBackspaceClearLabelIfNeeded];
         }
     }
-    for (NSInteger i = 0; i < deleteCount; i++) {
+    [[KBBackspaceUndoManager shared] captureAndDeleteBackwardFromProxy:proxy count:(NSUInteger)deleteCount];
-        [proxy deleteBackward];
+    [[KBInputBufferManager shared] applyHoldDeleteCount:(NSUInteger)deleteCount];
-    }
 
     NSTimeInterval interval = [self kb_backspaceRepeatIntervalForElapsed:elapsed];
     __weak typeof(self) weakSelf = self;
@@ -193,34 +210,77 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
         whitespaceSet = [NSCharacterSet whitespaceAndNewlineCharacterSet];
         asciiWordSet = [NSCharacterSet characterSetWithCharactersInString:
                         @"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_"];
-        punctuationSet = [NSCharacterSet punctuationCharacterSet];
+        NSMutableCharacterSet *punct = [[NSCharacterSet punctuationCharacterSet] mutableCopy];
+        // 补齐常见中文/全角标点（避免 chunk 总是只删 1 个符号）
+        [punct addCharactersInString:@"，。！？；：、（）【】《》“”‘’·…—"];
+        punctuationSet = [punct copy];
     });
 
     __block NSInteger deleteCount = 0;
-    __block KBBackspaceChunkClass chunkClass = KBBackspaceChunkClassUnknown;
+    typedef NS_ENUM(NSInteger, KBBackspaceChunkPhase) {
+        KBBackspaceChunkPhaseWhitespace = 0,
+        KBBackspaceChunkPhasePunctuation,
+        KBBackspaceChunkPhaseCore
+    };
+    __block KBBackspaceChunkPhase phase = KBBackspaceChunkPhaseWhitespace;
+    __block KBBackspaceChunkClass coreClass = KBBackspaceChunkClassUnknown;
+
     [context enumerateSubstringsInRange:NSMakeRange(0, context.length)
                                 options:NSStringEnumerationByComposedCharacterSequences | NSStringEnumerationReverse
                              usingBlock:^(NSString *substring, __unused NSRange substringRange, __unused NSRange enclosingRange, BOOL *stop) {
         if (substring.length == 0) { return; }
-        KBBackspaceChunkClass currentClass = KBBackspaceChunkClassOther;
+        if (deleteCount >= maxCount) {
-        if ([substring rangeOfCharacterFromSet:whitespaceSet].location != NSNotFound) {
-            currentClass = KBBackspaceChunkClassWhitespace;
-        } else if ([substring rangeOfCharacterFromSet:asciiWordSet].location != NSNotFound) {
-            currentClass = KBBackspaceChunkClassASCIIWord;
-        } else if ([substring rangeOfCharacterFromSet:punctuationSet].location != NSNotFound) {
-            currentClass = KBBackspaceChunkClassPunctuation;
-        }
-
-        if (chunkClass == KBBackspaceChunkClassUnknown) {
-            chunkClass = currentClass;
-        } else if (chunkClass != currentClass) {
             *stop = YES;
             return;
         }
 
+        KBBackspaceChunkClass currentClass = KBBackspaceChunkClassOther;
+        if ([substring rangeOfCharacterFromSet:whitespaceSet].location != NSNotFound) {
+            currentClass = KBBackspaceChunkClassWhitespace;
+        } else if ([substring rangeOfCharacterFromSet:punctuationSet].location != NSNotFound) {
+            currentClass = KBBackspaceChunkClassPunctuation;
+        } else if ([substring rangeOfCharacterFromSet:asciiWordSet].location != NSNotFound) {
+            currentClass = KBBackspaceChunkClassASCIIWord;
+        }
+
+        BOOL consumed = NO;
+        while (!consumed) {
+            if (phase == KBBackspaceChunkPhaseWhitespace) {
+                if (currentClass == KBBackspaceChunkClassWhitespace) {
                     deleteCount += 1;
+                    consumed = YES;
+                } else {
+                    phase = KBBackspaceChunkPhasePunctuation;
+                }
+                continue;
+            }
+
+            if (phase == KBBackspaceChunkPhasePunctuation) {
+                if (currentClass == KBBackspaceChunkClassPunctuation) {
+                    deleteCount += 1;
+                    consumed = YES;
+                } else {
+                    phase = KBBackspaceChunkPhaseCore;
+                }
+                continue;
+            }
+
+            // phase == Core：连续删同一类（ASCII 单词 / 其它），让效果更像微信“几个字一组”
+            if (coreClass == KBBackspaceChunkClassUnknown) {
+                coreClass = currentClass;
+            }
+            if (currentClass != coreClass) {
+                *stop = YES;
+                consumed = YES;
+                continue;
+            }
+            deleteCount += 1;
+            consumed = YES;
+        }
+
         if (deleteCount >= maxCount) {
             *stop = YES;
+            return;
         }
     }];
 
@@ -229,13 +289,16 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
 
 - (NSInteger)kb_clearDeleteCountForContext:(NSString *)context
                                hitBoundary:(BOOL *)hitBoundary {
-    if (context.length == 0) { return kKBBackspaceClearBatchSize; }
+    if (context.length == 0) {
+        if (hitBoundary) { *hitBoundary = NO; }
+        return 1;
+    }
 
     static NSCharacterSet *sentenceBoundarySet = nil;
     static NSCharacterSet *whitespaceSet = nil;
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
-        sentenceBoundarySet = [NSCharacterSet characterSetWithCharactersInString:@".!?;。！？；…\n"];
+        sentenceBoundarySet = [NSCharacterSet characterSetWithCharactersInString:@".!?。！？"];
         whitespaceSet = [NSCharacterSet whitespaceAndNewlineCharacterSet];
     });
 
@@ -310,6 +373,12 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
             shouldClear = [self kb_isPointInsideBackspaceClearLabel:point];
         }
     }
+#if DEBUG
+    NSLog(@"[kb_handleBackspaceLongPressEnded] shouldClear=%@ highlighted=%@ labelHidden=%@",
+          shouldClear ? @"YES" : @"NO",
+          self.backspaceClearHighlighted ? @"YES" : @"NO",
+          self.backspaceClearLabel.hidden ? @"YES" : @"NO");
+#endif
     self.backspaceHoldActive = NO;
     self.backspaceChunkModeActive = NO;
     self.backspaceHoldToken += 1;
@@ -320,6 +389,8 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
     } else {
         self.pendingClearBefore = nil;
         self.pendingClearAfter = nil;
+        [[KBInputBufferManager shared] clearPendingClearSnapshot];
+        [[KBInputBufferManager shared] commitLiveToManual];
     }
 }
 
@@ -431,13 +502,14 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
     UIResponder *start = (UIResponder *)([self kb_hostView] ?: self.backspaceButton);
     UIInputViewController *ivc = KBFindInputViewController(start);
     if (ivc) {
-        NSString *before = self.pendingClearBefore ?: (ivc.textDocumentProxy.documentContextBeforeInput ?: @"");
+        id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
-        NSString *after = self.pendingClearAfter ?: (ivc.textDocumentProxy.documentContextAfterInput ?: @"");
+        [[KBInputBufferManager shared] refreshFromProxyIfPossible:proxy];
-        [[KBBackspaceUndoManager shared] recordClearWithContextBefore:before after:after];
     }
     self.pendingClearBefore = nil;
     self.pendingClearAfter = nil;
+    [[KBInputBufferManager shared] clearPendingClearSnapshot];
     self.backspaceClearToken += 1;
+    self.backspaceClearPhase = KBClearPhaseSkipWhitespace;
     NSUInteger token = self.backspaceClearToken;
     [self kb_clearAllInputStepForToken:token guard:0 emptyRounds:0];
 }
@@ -450,40 +522,101 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
     UIInputViewController *ivc = KBFindInputViewController(start);
     if (!ivc) { return; }
     id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
-    NSString *before = proxy.documentContextBeforeInput ?: @"";
-    NSInteger count = before.length;
-    NSInteger batch = 0;
     NSInteger nextEmptyRounds = emptyRounds;
-    BOOL hitBoundary = NO;
+    static NSCharacterSet *stopBoundarySet = nil;
-    if (count > 0) {
+    static NSCharacterSet *trailingBoundarySet = nil;
-        batch = [self kb_clearDeleteCountForContext:before hitBoundary:&hitBoundary];
+    static NSCharacterSet *trailingWhitespaceSet = nil;
-        nextEmptyRounds = 0;
+    static dispatch_once_t onceToken;
-    } else {
+    dispatch_once(&onceToken, ^{
-        batch = kKBBackspaceClearBatchSize;
+        // stopBoundary: 遇到这些符号就停（不删除它）
-        nextEmptyRounds = emptyRounds + 1;
+        // - 句末符号：. ! ? 。！？
-    }
+        // - 省略号：…（中文里“……”常用作句/段落的停顿）
-    if (batch <= 0) { batch = 1; }
+        // - 换行：\n \r（段落边界，避免一次“清空”跨段把全文删完）
+        stopBoundarySet = [NSCharacterSet characterSetWithCharactersInString:@".!?。！？…\n\r\u2028\u2029"];
 
-    if (guard >= kKBBackspaceClearMaxDeletes ||
+        // trailingBoundary: 允许作为“尾部句末符号”先删掉，再继续删上一句（更接近微信体验）
-        nextEmptyRounds > kKBBackspaceClearEmptyContextMaxRounds) {
+        // 注意：不要把换行/省略号放进来，否则可能跨段/跨停顿继续删。
+        trailingBoundarySet = [NSCharacterSet characterSetWithCharactersInString:@".!?。！？"];
+
+        // trailingWhitespace: 只跳过空格/Tab（不包含换行，换行由 stopBoundarySet 处理）
+        trailingWhitespaceSet = [NSCharacterSet whitespaceCharacterSet];
+    });
+    KBClearPhase phase = self.backspaceClearPhase;
+
+    NSInteger deletedThisTick = 0;
+    BOOL shouldStop = NO;
+    NSString *lastBefore = nil;
+    for (NSInteger i = 0; i < kKBBackspaceClearDeletesPerTick; i++) {
+        NSString *before = proxy.documentContextBeforeInput ?: @"";
+        if (before.length == 0) {
+            nextEmptyRounds += 1;
+            // 宿主（微信/QQ 等）可能在长文本场景下返回空 context，即使还有很多内容。
+            // 为了避免一次“清空”误删全文：一旦拿不到 before，就立刻停止本次清空。
+            shouldStop = YES;
+            break;
+        }
+        nextEmptyRounds = 0;
+
+        if (lastBefore && [before isEqualToString:lastBefore] && deletedThisTick > 0) {
+            // 宿主未及时刷新 context，留到下一 tick 再继续，避免越界/重复记录
+            break;
+        }
+        lastBefore = before;
+
+        // 取最后一个组合字符
+        __block NSString *lastChar = @"";
+        [before enumerateSubstringsInRange:NSMakeRange(0, before.length)
+                                   options:NSStringEnumerationByComposedCharacterSequences | NSStringEnumerationReverse
+                                usingBlock:^(NSString *substring, __unused NSRange substringRange, __unused NSRange enclosingRange, BOOL *stop) {
+            lastChar = substring ?: @"";
+            *stop = YES;
+        }];
+        if (lastChar.length == 0) { break; }
+
+        BOOL isWhitespace = ([lastChar rangeOfCharacterFromSet:trailingWhitespaceSet].location != NSNotFound);
+        BOOL isStopBoundary = ([lastChar rangeOfCharacterFromSet:stopBoundarySet].location != NSNotFound);
+        BOOL isTrailingBoundary = ([lastChar rangeOfCharacterFromSet:trailingBoundarySet].location != NSNotFound);
+
+        if (phase == KBClearPhaseSkipWhitespace) {
+            if (isWhitespace) {
+                [[KBBackspaceUndoManager shared] captureAndDeleteBackwardFromProxy:proxy count:1];
+                [[KBInputBufferManager shared] applyClearDeleteCount:1];
+                deletedThisTick += 1;
+                continue;
+            }
+            phase = KBClearPhaseSkipTrailingBoundary;
+        }
+
+        if (phase == KBClearPhaseSkipTrailingBoundary) {
+            if (isTrailingBoundary) {
+                [[KBBackspaceUndoManager shared] captureAndDeleteBackwardFromProxy:proxy count:1];
+                [[KBInputBufferManager shared] applyClearDeleteCount:1];
+                deletedThisTick += 1;
+                continue;
+            }
+            phase = KBClearPhaseDeleteUntilBoundary;
+        }
+
+        // phase == DeleteUntilBoundary
+        if (isStopBoundary) {
+            shouldStop = YES; // 保留该句末符号
+            break;
+        }
+        [[KBBackspaceUndoManager shared] captureAndDeleteBackwardFromProxy:proxy count:1];
+        [[KBInputBufferManager shared] applyClearDeleteCount:1];
+        deletedThisTick += 1;
+        if (guard + deletedThisTick >= kKBBackspaceClearMaxDeletes) { break; }
+        if (deletedThisTick >= kKBBackspaceClearMaxStep) { break; }
+    }
+
+    self.backspaceClearPhase = phase;
+    NSInteger nextGuard = guard + deletedThisTick;
+    if (nextGuard >= kKBBackspaceClearMaxDeletes ||
+        nextEmptyRounds > kKBBackspaceClearEmptyContextMaxRounds ||
+        shouldStop) {
         return;
     }
 
-    for (NSInteger i = 0; i < batch; i++) {
-        [proxy deleteBackward];
-    }
-
-    NSInteger nextGuard = guard + batch;
-    BOOL shouldContinue = NO;
-    if (count > 0 && !hitBoundary) {
-        if (count > batch) {
-            shouldContinue = YES;
-        } else if ([proxy hasText]) {
-            shouldContinue = YES;
-        }
-    }
-
-    if (!shouldContinue) { return; }
     __weak typeof(self) weakSelf = self;
     dispatch_after(dispatch_time(DISPATCH_TIME_NOW,
                                  (int64_t)(kKBBackspaceClearBatchInterval * NSEC_PER_SEC)),
@@ -513,7 +646,6 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
 }
 
 - (void)kb_capturePendingClearSnapshotIfNeeded {
-    if ([KBBackspaceUndoManager shared].hasUndo) { return; }
     if (self.pendingClearBefore.length > 0 || self.pendingClearAfter.length > 0) { return; }
     UIResponder *start = (UIResponder *)([self kb_hostView] ?: self.backspaceButton);
     UIInputViewController *ivc = KBFindInputViewController(start);
@@ -521,6 +653,10 @@ typedef NS_ENUM(NSInteger, KBBackspaceChunkClass) {
     id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
     self.pendingClearBefore = proxy.documentContextBeforeInput ?: @"";
     self.pendingClearAfter = proxy.documentContextAfterInput ?: @"";
+#if DEBUG
+    NSLog(@"[kb_capturePendingClearSnapshotIfNeeded/before] len=%lu text=%@", (unsigned long)self.pendingClearBefore.length, self.pendingClearBefore);
+    NSLog(@"[kb_capturePendingClearSnapshotIfNeeded/after] len=%lu text=%@", (unsigned long)self.pendingClearAfter.length, self.pendingClearAfter);
+#endif
 }
 
 @end

CustomKeyboard/Utils/KBBackspaceUndoManager.h

@@ -21,6 +21,9 @@ extern NSNotificationName const KBBackspaceUndoStateDidChangeNotification;
 /// 记录一次“立刻清空”删除的内容（基于 documentContextBeforeInput/AfterInput）。
 - (void)recordClearWithContextBefore:(NSString *)before after:(NSString *)after;
 
+/// 记录本次将被 deleteBackward 的内容，并执行 deleteBackward（支持多次累计，撤销时一次性插回）。
+- (void)captureAndDeleteBackwardFromProxy:(id<UITextDocumentProxy>)proxy count:(NSUInteger)count;
+
 /// 在指定 responder 处执行撤销（向光标处插回删除的内容）
 - (void)performUndoFromResponder:(UIResponder *)responder;
 

CustomKeyboard/Utils/KBBackspaceUndoManager.m

@@ -5,13 +5,38 @@
 
 #import "KBBackspaceUndoManager.h"
 #import "KBResponderUtils.h"
+#import "KBInputBufferManager.h"
 
 NSNotificationName const KBBackspaceUndoStateDidChangeNotification = @"KBBackspaceUndoStateDidChangeNotification";
 
+#if DEBUG
+static NSString *KBLogString(NSString *tag, NSString *text) {
+    NSString *safeTag = tag ?: @"";
+    NSString *safeText = text ?: @"";
+    if (safeText.length <= 2000) {
+        return [NSString stringWithFormat:@"[%@] len=%lu text=%@", safeTag, (unsigned long)safeText.length, safeText];
+    }
+    NSString *head = [safeText substringToIndex:800];
+    NSString *tail = [safeText substringFromIndex:safeText.length - 800];
+    return [NSString stringWithFormat:@"[%@] len=%lu head=%@ ... tail=%@", safeTag, (unsigned long)safeText.length, head, tail];
+}
+#define KB_UNDO_LOG(tag, text) NSLog(@"%@", KBLogString((tag), (text)))
+#else
+#define KB_UNDO_LOG(tag, text) do {} while(0)
+#endif
+
+typedef NS_ENUM(NSInteger, KBUndoSnapshotSource) {
+    KBUndoSnapshotSourceNone = 0,
+    KBUndoSnapshotSourceDeletionSnapshot,
+    KBUndoSnapshotSourceClear
+};
+
 @interface KBBackspaceUndoManager ()
 @property (nonatomic, copy) NSString *undoText;
 @property (nonatomic, assign) NSInteger undoAfterLength;
 @property (nonatomic, assign) BOOL hasUndo;
+@property (nonatomic, assign) KBUndoSnapshotSource snapshotSource;
+@property (nonatomic, strong) NSMutableArray<NSString *> *undoDeletedPieces;
 @end
 
 @implementation KBBackspaceUndoManager
@@ -29,55 +54,189 @@ NSNotificationName const KBBackspaceUndoStateDidChangeNotification = @"KBBackspa
     if (self = [super init]) {
         _undoText = @"";
         _undoAfterLength = 0;
+        _snapshotSource = KBUndoSnapshotSourceNone;
+        _undoDeletedPieces = [NSMutableArray array];
     }
     return self;
 }
 
+- (void)captureAndDeleteBackwardFromProxy:(id<UITextDocumentProxy>)proxy count:(NSUInteger)count {
+    if (!proxy || count == 0) { return; }
+
+    NSString *selected = proxy.selectedText ?: @"";
+    NSString *ctxBefore = proxy.documentContextBeforeInput ?: @"";
+    NSString *ctxAfter = proxy.documentContextAfterInput ?: @"";
+    NSUInteger ctxLen = ctxBefore.length + ctxAfter.length;
+    BOOL isSelectAllLike = (selected.length > 0 &&
+                            (ctxLen == 0 || selected.length >= MAX((NSUInteger)40, ctxLen * 2)));
+    if (isSelectAllLike) {
+        // “全选删除”在微信/QQ中通常拿不到可靠的全文，因此禁用撤销，避免插回错误/不完整内容。
+        if (self.hasUndo) {
+            [self registerNonClearAction];
+        }
+#if DEBUG
+        KB_UNDO_LOG(@"captureAndDelete/selectAllDisableUndo", selected);
+#endif
+        [proxy deleteBackward];
+        [[KBInputBufferManager shared] resetWithText:@""];
+        return;
+    }
+
+    if (!self.hasUndo) {
+        [self.undoDeletedPieces removeAllObjects];
+        self.undoText = @"";
+        self.undoAfterLength = 0;
+        self.snapshotSource = KBUndoSnapshotSourceDeletionSnapshot;
+        [self kb_updateHasUndo:YES];
+    }
+
+    BOOL didAppend = NO;
+    NSString *lastObservedBefore = nil;
+    for (NSUInteger i = 0; i < count; i++) {
+        NSString *before = proxy.documentContextBeforeInput ?: @"";
+        if (before.length > 0) {
+            // 若宿主在同一 runloop 内不更新 context，则跳过记录，避免把同一个字符重复记录成“多句”。
+            if (lastObservedBefore && [before isEqualToString:lastObservedBefore]) {
+                // still delete, but don't record
+            } else {
+                NSString *piece = [self kb_lastComposedCharacterFromString:before];
+                if (piece.length > 0) {
+                    [self.undoDeletedPieces addObject:piece];
+                    didAppend = YES;
+                }
+                lastObservedBefore = before;
+            }
+        }
+        [proxy deleteBackward];
+    }
+
+#if DEBUG
+    if (didAppend) {
+        NSUInteger piecesCount = self.undoDeletedPieces.count;
+        if (piecesCount <= 20) {
+            KB_UNDO_LOG(@"captureAndDelete/undoInsertTextNow", [self kb_buildUndoInsertTextFromPieces]);
+        } else if (piecesCount % 50 == 0) {
+            NSString *lastPiece = self.undoDeletedPieces.lastObject ?: @"";
+            NSLog(@"[captureAndDelete/undoPieces] pieces=%lu lastPiece=%@",
+                  (unsigned long)piecesCount,
+                  lastPiece);
+        }
+    }
+#endif
+}
+
 - (void)recordDeletionSnapshotBefore:(NSString *)before after:(NSString *)after {
-    if (self.undoText.length > 0) { return; }
+    if (self.hasUndo) { return; }
+    NSString *pending = [KBInputBufferManager shared].pendingClearSnapshot;
+    NSString *manual = [KBInputBufferManager shared].manualSnapshot;
+    NSString *fallbackText = (pending.length > 0) ? pending : ((manual.length > 0) ? manual : [KBInputBufferManager shared].liveText);
+    if (fallbackText.length > 0) {
+        self.undoText = fallbackText;
+        self.undoAfterLength = 0;
+        self.snapshotSource = KBUndoSnapshotSourceDeletionSnapshot;
+        KB_UNDO_LOG(@"recordDeletionSnapshot/fallback", self.undoText);
+        [self kb_updateHasUndo:YES];
+        return;
+    }
     NSString *safeBefore = before ?: @"";
     NSString *safeAfter = after ?: @"";
     NSString *full = [safeBefore stringByAppendingString:safeAfter];
     if (full.length == 0) { return; }
     self.undoText = full;
     self.undoAfterLength = (NSInteger)safeAfter.length;
+    self.snapshotSource = KBUndoSnapshotSourceDeletionSnapshot;
+    KB_UNDO_LOG(@"recordDeletionSnapshot/context", self.undoText);
+    [self kb_updateHasUndo:YES];
 }
 
 - (void)recordClearWithContextBefore:(NSString *)before after:(NSString *)after {
-    if (self.undoText.length == 0) {
+    NSString *pending = [KBInputBufferManager shared].pendingClearSnapshot;
+    NSString *manual = [KBInputBufferManager shared].manualSnapshot;
+    NSString *fallbackText = (pending.length > 0) ? pending : ((manual.length > 0) ? manual : [KBInputBufferManager shared].liveText);
+
     NSString *safeBefore = before ?: @"";
     NSString *safeAfter = after ?: @"";
-        NSString *full = [safeBefore stringByAppendingString:safeAfter];
+    NSString *contextText = [[safeBefore stringByAppendingString:safeAfter] copy];
-        if (full.length > 0) {
+
-            self.undoText = full;
+    NSString *candidate = (fallbackText.length > 0) ? fallbackText : contextText;
-            self.undoAfterLength = (NSInteger)safeAfter.length;
+    NSInteger candidateAfterLen = (fallbackText.length > 0) ? 0 : (NSInteger)safeAfter.length;
+
+    if (candidate.length == 0) { return; }
+
+    KB_UNDO_LOG(@"recordClear/candidate", candidate);
+
+    if (self.undoText.length > 0) {
+        if (self.snapshotSource == KBUndoSnapshotSourceClear) {
+            KB_UNDO_LOG(@"recordClear/ignored(alreadyClear)", self.undoText);
+            [self kb_updateHasUndo:YES];
+            return;
+        }
+        if (self.snapshotSource == KBUndoSnapshotSourceDeletionSnapshot) {
+            if (candidate.length > self.undoText.length) {
+                self.undoText = candidate;
+                self.undoAfterLength = candidateAfterLen;
+                KB_UNDO_LOG(@"recordClear/upgradedFromDeletion", self.undoText);
+            } else {
+                KB_UNDO_LOG(@"recordClear/keepDeletionSnapshot", self.undoText);
+            }
+            self.snapshotSource = KBUndoSnapshotSourceClear;
+            [self kb_updateHasUndo:YES];
+            return;
         }
     }
-    if (self.undoText.length == 0) { return; }
+
+    self.undoText = candidate;
+    self.undoAfterLength = candidateAfterLen;
+    self.snapshotSource = KBUndoSnapshotSourceClear;
+    KB_UNDO_LOG(@"recordClear/set", self.undoText);
     [self kb_updateHasUndo:YES];
 }
 
 - (void)performUndoFromResponder:(UIResponder *)responder {
-    if (self.undoText.length == 0) { return; }
+    if (!self.hasUndo) { return; }
     UIInputViewController *ivc = KBFindInputViewController(responder);
     if (!ivc) { return; }
     id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
+    NSString *curBefore = proxy.documentContextBeforeInput ?: @"";
+    NSString *curAfter = proxy.documentContextAfterInput ?: @"";
+    KB_UNDO_LOG(@"performUndo/currentBefore", curBefore);
+    KB_UNDO_LOG(@"performUndo/currentAfter", curAfter);
+    NSString *insertText = [self kb_buildUndoInsertTextFromPieces];
+    if (insertText.length > 0) {
+        KB_UNDO_LOG(@"performUndo/insertDeletedText", insertText);
+        [proxy insertText:insertText];
+        [[KBInputBufferManager shared] appendText:insertText];
+    } else if (self.undoText.length > 0) {
+        KB_UNDO_LOG(@"performUndo/fallbackUndoText", self.undoText);
         [self kb_clearAllTextForProxy:proxy];
         [proxy insertText:self.undoText];
         if (self.undoAfterLength > 0 &&
             [proxy respondsToSelector:@selector(adjustTextPositionByCharacterOffset:)]) {
             [proxy adjustTextPositionByCharacterOffset:-self.undoAfterLength];
         }
-
+        [[KBInputBufferManager shared] resetWithText:self.undoText];
+    } else {
+        return;
+    }
     self.undoText = @"";
     self.undoAfterLength = 0;
+    self.snapshotSource = KBUndoSnapshotSourceNone;
+    [self.undoDeletedPieces removeAllObjects];
     [self kb_updateHasUndo:NO];
 }
 
 - (void)registerNonClearAction {
-    if (self.undoText.length == 0) { return; }
+    if (!self.hasUndo) { return; }
+    if (self.undoText.length > 0) {
+        KB_UNDO_LOG(@"registerNonClearAction/clearUndoText", self.undoText);
+    }
+    if (self.undoDeletedPieces.count > 0) {
+        KB_UNDO_LOG(@"registerNonClearAction/clearDeletedPieces", [self kb_buildUndoInsertTextFromPieces]);
+    }
     self.undoText = @"";
     self.undoAfterLength = 0;
+    self.snapshotSource = KBUndoSnapshotSourceNone;
+    [self.undoDeletedPieces removeAllObjects];
     [self kb_updateHasUndo:NO];
 }
 
@@ -89,6 +248,29 @@ NSNotificationName const KBBackspaceUndoStateDidChangeNotification = @"KBBackspa
     [[NSNotificationCenter defaultCenter] postNotificationName:KBBackspaceUndoStateDidChangeNotification object:self];
 }
 
+- (NSString *)kb_lastComposedCharacterFromString:(NSString *)text {
+     if (text.length == 0) { return @""; }
+     __block NSString *last = @"";
+     [text enumerateSubstringsInRange:NSMakeRange(0, text.length)
+                              options:NSStringEnumerationByComposedCharacterSequences | NSStringEnumerationReverse
+                           usingBlock:^(NSString *substring, __unused NSRange substringRange, __unused NSRange enclosingRange, BOOL *stop) {
+         last = substring ?: @"";
+         *stop = YES;
+     }];
+     return last ?: @"";
+ }
+
+- (NSString *)kb_buildUndoInsertTextFromPieces {
+    if (self.undoDeletedPieces.count == 0) { return @""; }
+    NSMutableString *result = [NSMutableString string];
+    for (NSInteger i = (NSInteger)self.undoDeletedPieces.count - 1; i >= 0; i--) {
+         NSString *piece = self.undoDeletedPieces[(NSUInteger)i] ?: @"";
+         if (piece.length == 0) { continue; }
+         [result appendString:piece];
+     }
+     return result;
+ }
+
 static const NSInteger kKBUndoClearMaxRounds = 200;
 
 - (void)kb_clearAllTextForProxy:(id<UITextDocumentProxy>)proxy {

CustomKeyboard/Utils/KBInputBufferManager.h

@@ -0,0 +1,34 @@
+#import <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@protocol UITextDocumentProxy;
+
+@interface KBInputBufferManager : NSObject
+
++ (instancetype)shared;
+
+@property (nonatomic, copy, readonly) NSString *liveText;
+@property (nonatomic, copy, readonly) NSString *manualSnapshot;
+@property (nonatomic, copy, readonly) NSString *pendingClearSnapshot;
+
+- (void)seedIfEmptyWithContextBefore:(nullable NSString *)before after:(nullable NSString *)after;
+- (void)updateFromExternalContextBefore:(nullable NSString *)before after:(nullable NSString *)after;
+- (void)refreshFromProxyIfPossible:(nullable id<UITextDocumentProxy>)proxy;
+- (void)prepareSnapshotForDeleteWithContextBefore:(nullable NSString *)before
+                                            after:(nullable NSString *)after;
+- (void)beginPendingClearSnapshot;
+- (void)clearPendingClearSnapshot;
+- (void)resetWithText:(NSString *)text;
+- (void)appendText:(NSString *)text;
+- (void)deleteBackwardByCount:(NSUInteger)count;
+- (void)replaceTailWithText:(NSString *)text deleteCount:(NSUInteger)count;
+- (void)applyHoldDeleteCount:(NSUInteger)count;
+- (void)applyClearDeleteCount:(NSUInteger)count;
+- (void)clearAllLiveText;
+- (void)commitLiveToManual;
+- (void)restoreManualSnapshot;
+
+@end
+
+NS_ASSUME_NONNULL_END

CustomKeyboard/Utils/KBInputBufferManager.m

@@ -0,0 +1,279 @@
+#import "KBInputBufferManager.h"
+#import <UIKit/UIKit.h>
+
+#if DEBUG
+static NSString *KBLogString2(NSString *tag, NSString *text) {
+    NSString *safeTag = tag ?: @"";
+    NSString *safeText = text ?: @"";
+    if (safeText.length <= 2000) {
+        return [NSString stringWithFormat:@"[%@] len=%lu text=%@", safeTag, (unsigned long)safeText.length, safeText];
+    }
+    NSString *head = [safeText substringToIndex:800];
+    NSString *tail = [safeText substringFromIndex:safeText.length - 800];
+    return [NSString stringWithFormat:@"[%@] len=%lu head=%@ ... tail=%@", safeTag, (unsigned long)safeText.length, head, tail];
+}
+#define KB_BUF_LOG(tag, text) NSLog(@"❤️=%@", KBLogString2((tag), (text)))
+#else
+#define KB_BUF_LOG(tag, text) do {} while(0)
+#endif
+
+@interface KBInputBufferManager ()
+@property (nonatomic, copy, readwrite) NSString *liveText;
+@property (nonatomic, copy, readwrite) NSString *manualSnapshot;
+@property (nonatomic, copy, readwrite) NSString *pendingClearSnapshot;
+@property (nonatomic, assign) BOOL manualSnapshotDirty;
+@end
+
+@implementation KBInputBufferManager
+
++ (instancetype)shared {
+    static KBInputBufferManager *mgr = nil;
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+        mgr = [[KBInputBufferManager alloc] init];
+    });
+    return mgr;
+}
+
+- (instancetype)init {
+    if (self = [super init]) {
+        _liveText = @"";
+        _manualSnapshot = @"";
+        _pendingClearSnapshot = @"";
+        _manualSnapshotDirty = NO;
+    }
+    return self;
+}
+
+- (void)seedIfEmptyWithContextBefore:(NSString *)before after:(NSString *)after {
+    if (self.liveText.length > 0 || self.manualSnapshot.length > 0) { return; }
+    NSString *safeBefore = before ?: @"";
+    NSString *safeAfter = after ?: @"";
+    NSString *full = [safeBefore stringByAppendingString:safeAfter];
+    if (full.length == 0) { return; }
+    self.liveText = full;
+    self.manualSnapshot = full;
+    self.manualSnapshotDirty = NO;
+    KB_BUF_LOG(@"seedIfEmpty", full);
+}
+
+- (void)updateFromExternalContextBefore:(NSString *)before after:(NSString *)after {
+    NSString *safeBefore = before ?: @"";
+    NSString *safeAfter = after ?: @"";
+    NSString *context = [safeBefore stringByAppendingString:safeAfter];
+    if (context.length == 0) { return; }
+
+    // 微信/QQ 等宿主通常只提供光标附近“截断窗口”，不应当作为全文快照。
+    // 这里只更新 liveText，给删除/清空逻辑做参考；manualSnapshot 仅由键盘自身输入/撤销来维护。
+    self.liveText = context;
+    self.manualSnapshotDirty = YES;
+#if DEBUG
+    static NSUInteger sExternalLogCounter = 0;
+    sExternalLogCounter += 1;
+    if (sExternalLogCounter % 12 == 0) {
+        KB_BUF_LOG(@"updateFromExternalContext/liveOnly", context);
+    }
+#endif
+}
+
+- (void)refreshFromProxyIfPossible:(id<UITextDocumentProxy>)proxy {
+    NSString *harvested = [self kb_harvestFullTextFromProxy:proxy];
+    if (harvested.length == 0) {
+        KB_BUF_LOG(@"refreshFromProxy/failedOrUnsupported", @"");
+        return;
+    }
+
+    BOOL manualEmpty = (self.manualSnapshot.length == 0);
+    BOOL longerThanManual = (harvested.length > self.manualSnapshot.length);
+    if (!(manualEmpty || longerThanManual)) {
+        KB_BUF_LOG(@"refreshFromProxy/ignoredShorter", harvested);
+        return;
+    }
+
+    self.liveText = harvested;
+    self.manualSnapshot = harvested;
+    self.manualSnapshotDirty = NO;
+    KB_BUF_LOG(@"refreshFromProxy/accepted", harvested);
+}
+
+- (void)prepareSnapshotForDeleteWithContextBefore:(NSString *)before
+                                            after:(NSString *)after {
+    NSString *safeBefore = before ?: @"";
+    NSString *safeAfter = after ?: @"";
+    NSString *context = [safeBefore stringByAppendingString:safeAfter];
+
+    BOOL manualValid = (self.manualSnapshot.length > 0 &&
+                        (context.length == 0 ||
+                         (self.manualSnapshot.length >= context.length &&
+                          [self.manualSnapshot rangeOfString:context].location != NSNotFound)));
+    if (manualValid) { return; }
+
+    if (self.liveText.length > 0) {
+        self.manualSnapshot = self.liveText;
+        self.manualSnapshotDirty = NO;
+        KB_BUF_LOG(@"prepareSnapshotForDelete/fromLiveText", self.manualSnapshot);
+        return;
+    }
+    if (context.length > 0) {
+        self.manualSnapshot = context;
+        self.manualSnapshotDirty = NO;
+        KB_BUF_LOG(@"prepareSnapshotForDelete/fromContext", self.manualSnapshot);
+    }
+}
+
+- (void)beginPendingClearSnapshot {
+    if (self.pendingClearSnapshot.length > 0) { return; }
+    if (self.manualSnapshot.length > 0) {
+        self.pendingClearSnapshot = self.manualSnapshot;
+        KB_BUF_LOG(@"beginPendingClearSnapshot/fromManual", self.pendingClearSnapshot);
+        return;
+    }
+    if (self.liveText.length > 0) {
+        self.pendingClearSnapshot = self.liveText;
+        KB_BUF_LOG(@"beginPendingClearSnapshot/fromLive", self.pendingClearSnapshot);
+    }
+}
+
+- (void)clearPendingClearSnapshot {
+    self.pendingClearSnapshot = @"";
+}
+
+- (void)resetWithText:(NSString *)text {
+    NSString *safe = text ?: @"";
+    self.liveText = safe;
+    self.manualSnapshot = safe;
+    self.pendingClearSnapshot = @"";
+    self.manualSnapshotDirty = NO;
+    KB_BUF_LOG(@"resetWithText", safe);
+}
+
+- (void)appendText:(NSString *)text {
+    if (text.length == 0) { return; }
+    [self kb_syncManualSnapshotIfNeeded];
+    self.liveText = [self.liveText stringByAppendingString:text];
+    self.manualSnapshot = [self.manualSnapshot stringByAppendingString:text];
+}
+
+- (void)deleteBackwardByCount:(NSUInteger)count {
+    if (count == 0) { return; }
+    self.liveText = [self kb_stringByDeletingComposedCharacters:count from:self.liveText];
+    self.manualSnapshot = [self kb_stringByDeletingComposedCharacters:count from:self.manualSnapshot];
+}
+
+- (void)replaceTailWithText:(NSString *)text deleteCount:(NSUInteger)count {
+    [self kb_syncManualSnapshotIfNeeded];
+    [self deleteBackwardByCount:count];
+    [self appendText:text];
+}
+
+- (void)applyHoldDeleteCount:(NSUInteger)count {
+    if (count == 0) { return; }
+    self.liveText = [self kb_stringByDeletingComposedCharacters:count from:self.liveText];
+    self.manualSnapshotDirty = YES;
+}
+
+- (void)applyClearDeleteCount:(NSUInteger)count {
+    if (count == 0) { return; }
+    self.liveText = [self kb_stringByDeletingComposedCharacters:count from:self.liveText];
+    self.manualSnapshotDirty = YES;
+}
+
+- (void)clearAllLiveText {
+    self.liveText = @"";
+    self.pendingClearSnapshot = @"";
+    self.manualSnapshotDirty = YES;
+}
+
+- (void)commitLiveToManual {
+    self.manualSnapshot = self.liveText ?: @"";
+    self.manualSnapshotDirty = NO;
+    KB_BUF_LOG(@"commitLiveToManual", self.manualSnapshot);
+}
+
+- (void)restoreManualSnapshot {
+    self.liveText = self.manualSnapshot ?: @"";
+}
+
+#pragma mark - Helpers
+
+- (void)kb_syncManualSnapshotIfNeeded {
+    if (!self.manualSnapshotDirty) { return; }
+    self.manualSnapshot = self.liveText ?: @"";
+    self.manualSnapshotDirty = NO;
+}
+
+- (NSString *)kb_stringByDeletingComposedCharacters:(NSUInteger)count
+                                               from:(NSString *)text {
+    if (count == 0) { return text ?: @""; }
+    NSString *source = text ?: @"";
+    if (source.length == 0) { return @""; }
+
+    __block NSUInteger removed = 0;
+    __block NSUInteger endIndex = source.length;
+    [source enumerateSubstringsInRange:NSMakeRange(0, source.length)
+                               options:NSStringEnumerationByComposedCharacterSequences | NSStringEnumerationReverse
+                            usingBlock:^(__unused NSString *substring, NSRange substringRange, __unused NSRange enclosingRange, BOOL *stop) {
+        removed += 1;
+        endIndex = substringRange.location;
+        if (removed >= count) {
+            *stop = YES;
+        }
+    }];
+    if (removed < count) { return @""; }
+    return [source substringToIndex:endIndex];
+}
+
+- (NSString *)kb_harvestFullTextFromProxy:(id<UITextDocumentProxy>)proxy {
+    if (!proxy) { return @""; }
+    if (![proxy respondsToSelector:@selector(adjustTextPositionByCharacterOffset:)]) { return @""; }
+
+    static const NSInteger kKBHarvestMaxRounds = 160;
+    static const NSInteger kKBHarvestMaxChars = 50000;
+
+    NSInteger movedToEnd = 0;
+    NSInteger movedLeft = 0;
+    NSMutableArray<NSString *> *chunks = [NSMutableArray array];
+    NSInteger totalChars = 0;
+
+    @try {
+        NSInteger guard = 0;
+        NSString *after = proxy.documentContextAfterInput ?: @"";
+        while (after.length > 0 && guard < kKBHarvestMaxRounds) {
+            NSInteger step = (NSInteger)after.length;
+            [(id)proxy adjustTextPositionByCharacterOffset:step];
+            movedToEnd += step;
+            guard += 1;
+            after = proxy.documentContextAfterInput ?: @"";
+        }
+
+        guard = 0;
+        NSString *before = proxy.documentContextBeforeInput ?: @"";
+        while (before.length > 0 && guard < kKBHarvestMaxRounds && totalChars < kKBHarvestMaxChars) {
+            [chunks addObject:before];
+            totalChars += (NSInteger)before.length;
+            NSInteger step = (NSInteger)before.length;
+            [(id)proxy adjustTextPositionByCharacterOffset:-step];
+            movedLeft += step;
+            guard += 1;
+            before = proxy.documentContextBeforeInput ?: @"";
+        }
+    } @finally {
+        if (movedLeft != 0) {
+            [(id)proxy adjustTextPositionByCharacterOffset:movedLeft];
+        }
+        if (movedToEnd != 0) {
+            [(id)proxy adjustTextPositionByCharacterOffset:-movedToEnd];
+        }
+    }
+
+    if (chunks.count == 0) { return @""; }
+    NSMutableString *result = [NSMutableString stringWithCapacity:(NSUInteger)totalChars];
+    for (NSInteger i = (NSInteger)chunks.count - 1; i >= 0; i--) {
+        NSString *part = chunks[(NSUInteger)i] ?: @"";
+        if (part.length == 0) { continue; }
+        [result appendString:part];
+    }
+    return result;
+}
+
+@end

CustomKeyboard/View/KBFunctionView.m

@@ -27,6 +27,7 @@
 #import "KBBizCode.h"
 #import "KBBackspaceLongPressHandler.h"
 #import "KBBackspaceUndoManager.h"
+#import "KBInputBufferManager.h"
 
 @interface KBFunctionView () <KBFunctionBarViewDelegate, KBStreamOverlayViewDelegate, KBFunctionTagListViewDelegate>
 // UI
@@ -721,6 +722,8 @@ static void KBULDarwinCallback(CFNotificationCenterRef center, void *observer, C
 // - 无论允许/拒绝，都把本次 changeCount 记为已处理，避免一直重复询问。
 
 - (void)startPasteboardMonitor {
+    // 禁用自动读取剪贴板，避免触发系统“允许粘贴”弹窗
+    return;
     // 未开启“完全访问”时不做自动读取，避免宿主/系统拒绝并刷错误日志
     if (![[KBFullAccessManager shared] hasFullAccess]) return;
     if (self.pasteboardTimer) return;
@@ -775,9 +778,11 @@ static void KBULDarwinCallback(CFNotificationCenterRef center, void *observer, C
     NSLog(@"点击：删除");
     UIInputViewController *ivc = KBFindInputViewController(self);
     id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
-    [[KBBackspaceUndoManager shared] recordDeletionSnapshotBefore:proxy.documentContextBeforeInput
+    [[KBInputBufferManager shared] refreshFromProxyIfPossible:proxy];
+    [[KBInputBufferManager shared] prepareSnapshotForDeleteWithContextBefore:proxy.documentContextBeforeInput
                                                                        after:proxy.documentContextAfterInput];
-    [proxy deleteBackward];
+    [[KBBackspaceUndoManager shared] captureAndDeleteBackwardFromProxy:proxy count:1];
+    [[KBInputBufferManager shared] applyHoldDeleteCount:1];
 }
 - (void)onTapClear {
     NSLog(@"点击：清空");
@@ -791,6 +796,7 @@ static void KBULDarwinCallback(CFNotificationCenterRef center, void *observer, C
     UIInputViewController *ivc = KBFindInputViewController(self);
     id<UITextDocumentProxy> proxy = ivc.textDocumentProxy;
     [proxy insertText:@"\n"];
+    [[KBInputBufferManager shared] appendText:@"\n"];
 }
 
 #pragma mark - Lazy

CustomKeyboard/View/KBStreamTextView.m

@@ -9,6 +9,7 @@
 
 #import "KBStreamTextView.h"
 #import "KBResponderUtils.h" // 通过响应链找到 UIInputViewController，并将文本输出到宿主
+#import "KBInputBufferManager.h"
 
 @interface KBStreamTextView ()
 
@@ -371,6 +372,7 @@ static inline NSString *KBTrimRight(NSString *s) {
             if (rawText.length > 0) {
                 [proxy insertText:rawText];
             }
+            [[KBInputBufferManager shared] resetWithText:rawText ?: @""];
         }
     }
 }

_DerivedData/Logs/Build/LogStoreManifest.plist

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>logFormatVersion</key>
+	<integer>11</integer>
+	<key>logs</key>
+	<dict/>
+</dict>
+</plist>

_DerivedData/Logs/Launch/LogStoreManifest.plist

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>logFormatVersion</key>
+	<integer>11</integer>
+	<key>logs</key>
+	<dict/>
+</dict>
+</plist>

_DerivedData/Logs/Localization/LogStoreManifest.plist

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>logFormatVersion</key>
+	<integer>11</integer>
+	<key>logs</key>
+	<dict/>
+</dict>
+</plist>

_DerivedData/Logs/Package/LogStoreManifest.plist

@@ -0,0 +1,47 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>logFormatVersion</key>
+	<integer>11</integer>
+	<key>logs</key>
+	<dict>
+		<key>800731DD-5595-43EC-B207-003BAB7870CE</key>
+		<dict>
+			<key>className</key>
+			<string>IDECommandLineBuildLog</string>
+			<key>documentTypeString</key>
+			<string>&lt;nil&gt;</string>
+			<key>domainType</key>
+			<string>Xcode.IDEActivityLogDomainType.BuildLog</string>
+			<key>fileName</key>
+			<string>800731DD-5595-43EC-B207-003BAB7870CE.xcactivitylog</string>
+			<key>hasPrimaryLog</key>
+			<true/>
+			<key>primaryObservable</key>
+			<dict>
+				<key>highLevelStatus</key>
+				<string>E</string>
+				<key>totalNumberOfAnalyzerIssues</key>
+				<integer>0</integer>
+				<key>totalNumberOfErrors</key>
+				<integer>1</integer>
+				<key>totalNumberOfTestFailures</key>
+				<integer>0</integer>
+				<key>totalNumberOfWarnings</key>
+				<integer>3</integer>
+			</dict>
+			<key>signature</key>
+			<string>Resolve Packages</string>
+			<key>timeStartedRecording</key>
+			<real>788359220.39837599</real>
+			<key>timeStoppedRecording</key>
+			<real>788359220.51885402</real>
+			<key>title</key>
+			<string>Resolve Packages</string>
+			<key>uniqueIdentifier</key>
+			<string>800731DD-5595-43EC-B207-003BAB7870CE</string>
+		</dict>
+	</dict>
+</dict>
+</plist>

_DerivedData/Logs/Test/LogStoreManifest.plist

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>logFormatVersion</key>
+	<integer>11</integer>
+	<key>logs</key>
+	<dict/>
+</dict>
+</plist>

_xcodebuild.xcresult/Info.plist

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>dateCreated</key>
+	<date>2025-12-25T12:40:20Z</date>
+	<key>externalLocations</key>
+	<array/>
+	<key>rootId</key>
+	<dict>
+		<key>hash</key>
+		<string>0~z4eUyi7LNyiJgMc9YvhirRPEbAqQY1U8Utz3Zonm5K5gXqlevHrHNamc2oelL32RyN2c9x-M59B2wBAeP3TOAg==</string>
+	</dict>
+	<key>storage</key>
+	<dict>
+		<key>backend</key>
+		<string>fileBacked2</string>
+		<key>compression</key>
+		<string>standard</string>
+	</dict>
+	<key>version</key>
+	<dict>
+		<key>major</key>
+		<integer>3</integer>
+		<key>minor</key>
+		<integer>53</integer>
+	</dict>
+</dict>
+</plist>

keyBoard.xcodeproj/project.pbxproj

@@ -225,6 +225,7 @@
 		A1B2C4212EB4B7A100000001 /* KBKeyboardPermissionManager.m in Sources */ = {isa = PBXBuildFile; fileRef = A1B2C4222EB4B7A100000001 /* KBKeyboardPermissionManager.m */; };
 		A1B2C9032FBD000100000001 /* KBBackspaceLongPressHandler.m in Sources */ = {isa = PBXBuildFile; fileRef = A1B2C9022FBD000100000001 /* KBBackspaceLongPressHandler.m */; };
 		A1B2C9052FBD000200000001 /* KBBackspaceUndoManager.m in Sources */ = {isa = PBXBuildFile; fileRef = A1B2C9042FBD000200000001 /* KBBackspaceUndoManager.m */; };
+		A1B2C9092FBD000200000005 /* KBInputBufferManager.m in Sources */ = {isa = PBXBuildFile; fileRef = A1B2C9082FBD000200000004 /* KBInputBufferManager.m */; };
 		A1B2D7022EB8C00100000001 /* KBLangTestVC.m in Sources */ = {isa = PBXBuildFile; fileRef = A1B2D7012EB8C00100000001 /* KBLangTestVC.m */; };
 		A1B2E1012EBC7AAA00000001 /* KBTopThreeView.m in Sources */ = {isa = PBXBuildFile; fileRef = A1B2E0022EBC7AAA00000001 /* KBTopThreeView.m */; };
 		A1B2E1022EBC7AAA00000001 /* HomeHotCell.m in Sources */ = {isa = PBXBuildFile; fileRef = A1B2E0042EBC7AAA00000001 /* HomeHotCell.m */; };
@@ -639,6 +640,8 @@
 		A1B2C9022FBD000100000001 /* KBBackspaceLongPressHandler.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = KBBackspaceLongPressHandler.m; sourceTree = "<group>"; };
 		A1B2C9032FBD000200000001 /* KBBackspaceUndoManager.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = KBBackspaceUndoManager.h; sourceTree = "<group>"; };
 		A1B2C9042FBD000200000001 /* KBBackspaceUndoManager.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = KBBackspaceUndoManager.m; sourceTree = "<group>"; };
+		A1B2C9072FBD000200000003 /* KBInputBufferManager.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = KBInputBufferManager.h; sourceTree = "<group>"; };
+		A1B2C9082FBD000200000004 /* KBInputBufferManager.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = KBInputBufferManager.m; sourceTree = "<group>"; };
 		A1B2D7002EB8C00100000001 /* KBLangTestVC.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = KBLangTestVC.h; sourceTree = "<group>"; };
 		A1B2D7012EB8C00100000001 /* KBLangTestVC.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = KBLangTestVC.m; sourceTree = "<group>"; };
 		A1B2E0012EBC7AAA00000001 /* KBTopThreeView.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = KBTopThreeView.h; sourceTree = "<group>"; };
@@ -841,6 +844,8 @@
 				A1B2C9022FBD000100000001 /* KBBackspaceLongPressHandler.m */,
 				A1B2C9032FBD000200000001 /* KBBackspaceUndoManager.h */,
 				A1B2C9042FBD000200000001 /* KBBackspaceUndoManager.m */,
+				A1B2C9072FBD000200000003 /* KBInputBufferManager.h */,
+				A1B2C9082FBD000200000004 /* KBInputBufferManager.m */,
 			);
 			path = Utils;
 			sourceTree = "<group>";
@@ -1947,6 +1952,7 @@
 				04FC95702EB09516007BD342 /* KBFunctionView.m in Sources */,
 				A1B2C9032FBD000100000001 /* KBBackspaceLongPressHandler.m in Sources */,
 				A1B2C9052FBD000200000001 /* KBBackspaceUndoManager.m in Sources */,
+				A1B2C9092FBD000200000005 /* KBInputBufferManager.m in Sources */,
 				049FB23F2EC4B6EF00FAB05D /* KBULBridgeNotification.m in Sources */,
 				04791F992ED49CE7004E8522 /* KBFont.m in Sources */,
 				04FC956D2EB054B7007BD342 /* KBKeyboardView.m in Sources */,

keyBoard/Class/Pay/M/KBPayProductModel.m

@@ -17,12 +17,12 @@
 
 - (NSString *)coinsDisplayText {
     NSString *name = self.name ?: @"";
-    NSString *unit = self.unit ?: @"";
+//    NSString *unit = self.unit ?: @"";
-    if (name.length && unit.length) {
+    if (name.length) {
-        return [NSString stringWithFormat:@"%@ %@", name, unit];
+        return [NSString stringWithFormat:@"%@", name];
     }
     if (name.length) { return name; }
-    if (unit.length) { return unit; }
+//    if (unit.length) { return unit; }
     return @"";
 }