//
//  KBKeyboardView.m
//  CustomKeyboard
//

#import "KBKeyboardView.h"
#import "KBKeyButton.h"
#import "KBKey.h"
#import "KBBackspaceLongPressHandler.h"
#import "KBKeyboardLayoutConfig.h"
#import "KBKeyboardLayoutResolver.h"
#import "KBKeyboardKeyFactory.h"
#import "KBKeyboardLayoutEngine.h"
#import "KBKeyboardRowBuilder.h"
#import "KBKeyboardInputHandler.h"
#import "KBKeyboardLegacyBuilder.h"
#import "KBKeyboardLegacyLayoutProvider.h"
#import "KBKeyboardInteractionHandler.h"
#import "KBKeyboardRowContainerBuilder.h"

// 第二行字母行的左右占位比例（用于居中）
static const CGFloat kKBLettersRow2EdgeSpacerMultiplier = 0.5;

@interface KBKeyboardView ()
@property (nonatomic, strong) NSMutableArray<UIView *> *rowViews;
@property (nonatomic, strong) NSArray<NSArray<KBKey *> *> *keysForRows;
@property (nonatomic, strong) KBBackspaceLongPressHandler *backspaceHandler;
@property (nonatomic, strong) KBKeyboardLayoutConfig *layoutConfig;
@property (nonatomic, strong) KBKeyboardKeyFactory *keyFactory;
@property (nonatomic, strong) KBKeyboardLayoutEngine *layoutEngine;
@property (nonatomic, strong) KBKeyboardRowBuilder *rowBuilder;
@property (nonatomic, strong) KBKeyboardInputHandler *inputHandler;
@property (nonatomic, strong) KBKeyboardLegacyBuilder *legacyBuilder;
@property (nonatomic, strong) KBKeyboardLegacyLayoutProvider *legacyLayoutProvider;
@property (nonatomic, strong) KBKeyboardInteractionHandler *interactionHandler;
@property (nonatomic, strong) KBKeyboardRowContainerBuilder *rowContainerBuilder;
/// 跨行统一字符键宽度（按最多字符键的行计算），0 表示不启用
@property (nonatomic, assign) CGFloat kb_uniformCharKeyWidth;
/// 记录当前行间距，便于切换布局时判断是否需要重建容器
@property (nonatomic, assign) CGFloat kb_currentRowSpacing;
/// 记录当前顶/底间距，便于切换布局时判断是否需要重建容器
@property (nonatomic, assign) CGFloat kb_currentTopInset;
@property (nonatomic, assign) CGFloat kb_currentBottomInset;
@end

@implementation KBKeyboardView

- (instancetype)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        self.backgroundColor = [UIColor clearColor];
        _layoutStyle = KBKeyboardLayoutStyleLetters;
        // 默认小写：与需求一致，初始不开启 Shift
        _shiftOn = NO;
        _symbolsMoreOn = NO; // 数字面板默认第一页（123）

        // 从 App Group 读取当前 profileId 并设置布局
        NSString *profileId = [[KBKeyboardLayoutResolver sharedResolver] currentProfileId];
        if (profileId.length > 0) {
            _currentLayoutJsonId = [[KBKeyboardLayoutResolver sharedResolver] layoutJsonIdForProfileId:profileId];
            NSLog(@"[KBKeyboardView] Loaded profileId: %@, layoutJsonId: %@", profileId, _currentLayoutJsonId);
        } else {
            _currentLayoutJsonId = @"letters";
            NSLog(@"[KBKeyboardView] No profileId found, using default 'letters'");
        }

        self.layoutConfig = [KBKeyboardLayoutConfig sharedConfig];
        self.backspaceHandler = [[KBBackspaceLongPressHandler alloc] initWithContainerView:self];
        [self buildBase];
    }
    return self;
}

// 当切换大布局（字母/数字）时，重置数字二级页状态
- (void)setLayoutStyle:(KBKeyboardLayoutStyle)layoutStyle {
    _layoutStyle = layoutStyle;
    if (_layoutStyle != KBKeyboardLayoutStyleNumbers) {
        _symbolsMoreOn = NO;
    }
}

#pragma mark - Base Layout

- (void)buildBase {
    KBKeyboardLayout *layout = [self kb_currentLayout];
    NSArray<KBKeyboardRowConfig *> *rows = layout.rows ?: @[];
    if (rows.count == 0) {
        // Fallback: 至少创建 4 行容器
        rows = @[[KBKeyboardRowConfig new], [KBKeyboardRowConfig new],
                 [KBKeyboardRowConfig new], [KBKeyboardRowConfig new]];
    }
    CGFloat rowSpacing = [self.layoutEngine rowSpacingForLayout:layout];
    CGFloat topInset = [self.layoutEngine topInsetForLayout:layout];
    CGFloat bottomInset = [self.layoutEngine bottomInsetForLayout:layout];
    self.kb_currentRowSpacing = rowSpacing;
    self.kb_currentTopInset = topInset;
    self.kb_currentBottomInset = bottomInset;
    [self.rowContainerBuilder rebuildRowContainersForRows:rows
                                              inContainer:self
                                                 rowViews:self.rowViews
                                               rowSpacing:rowSpacing
                                                 topInset:topInset
                                              bottomInset:bottomInset];
    [self.interactionHandler bringPreviewToFrontIfNeededInContainer:self];
}

#pragma mark - Public

- (void)reloadKeys {
    [self.backspaceHandler bindDeleteButton:nil showClearLabel:NO];

    KBKeyboardLayout *layout = [self kb_currentLayout];
    CGFloat rowSpacing = [self.layoutEngine rowSpacingForLayout:layout];
    CGFloat topInset = [self.layoutEngine topInsetForLayout:layout];
    CGFloat bottomInset = [self.layoutEngine bottomInsetForLayout:layout];
    NSLog(@"[KBKeyboardView] reloadKeys: layoutName=%@ rows=%lu shiftRows=%lu shiftOn=%d",
          self.currentLayoutJsonId, (unsigned long)layout.rows.count, (unsigned long)layout.shiftRows.count, self.shiftOn);

    NSArray<KBKeyboardRowConfig *> *rows = nil;

    if (self.shiftOn && layout.shiftRows.count > 0) {
        rows = layout.shiftRows;
    } else {
        rows = layout.rows ?: @[];
    }

    NSLog(@"[KBKeyboardView] reloadKeys: usingRows=%lu currentContainers=%lu",
          (unsigned long)rows.count, (unsigned long)self.rowViews.count);

    // 行数变化时（如从 4 行布局切到 5 行注音布局），重建行容器
    if (rows.count >= 4 &&
        (rows.count != self.rowViews.count ||
         fabs(self.kb_currentRowSpacing - rowSpacing) > 0.1 ||
         fabs(self.kb_currentTopInset - topInset) > 0.1 ||
         fabs(self.kb_currentBottomInset - bottomInset) > 0.1)) {
        self.kb_currentRowSpacing = rowSpacing;
        self.kb_currentTopInset = topInset;
        self.kb_currentBottomInset = bottomInset;
        [self.rowContainerBuilder rebuildRowContainersForRows:rows
                                                  inContainer:self
                                                     rowViews:self.rowViews
                                                   rowSpacing:rowSpacing
                                                     topInset:topInset
                                                  bottomInset:bottomInset];
        [self.interactionHandler bringPreviewToFrontIfNeededInContainer:self];
    }

    // 移除旧按钮
    for (UIView *row in self.rowViews) {
        [row.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];
    }

    if (rows.count < 4) {
        NSLog(@"[KBKeyboardView] reloadKeys: rows.count < 4, fallback to legacy");
        self.kb_uniformCharKeyWidth = 0.0;
        [self kb_buildLegacyLayout];
        return;
    }

    // 计算跨行统一字符键宽度（若各行字符键数量不同，则按最多键的行为基准）
    self.kb_uniformCharKeyWidth = [self.layoutEngine calculateUniformCharKeyWidthForRows:rows
                                                                             keyFactory:self.keyFactory
                                                                                shiftOn:self.shiftOn];

    for (NSUInteger i = 0; i < rows.count && i < self.rowViews.count; i++) {
        [self.rowBuilder buildRow:self.rowViews[i]
                    withRowConfig:rows[i]
                 uniformCharWidth:self.kb_uniformCharKeyWidth
                          shiftOn:self.shiftOn
                 backspaceHandler:self.backspaceHandler
                           target:self
                           action:@selector(onKeyTapped:)];
    }

    NSUInteger totalButtons = [self kb_totalKeyButtonCount];
    NSLog(@"[KBKeyboardView] reloadKeys: totalButtons=%lu", (unsigned long)totalButtons);
    if (totalButtons == 0) {
        NSLog(@"[KBKeyboardView] config layout produced no keys, fallback to legacy.");
        for (UIView *row in self.rowViews) {
            [row.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];
        }
        [self kb_buildLegacyLayout];
    }
}

- (void)didMoveToWindow {
    [super didMoveToWindow];
    if (!self.window) { return; }
    if ([self kb_totalKeyButtonCount] > 0) { return; }
    // 兜底：系统编辑菜单切出切回等场景下，若按键丢失则自动重建。
    [self reloadKeys];
    // 自动重建后再触发一次上层主题应用，避免“按键恢复了但皮肤背景没恢复”。
    UIView *container = self.superview;
    if ([container respondsToSelector:@selector(kb_applyTheme)]) {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
        [container performSelector:@selector(kb_applyTheme)];
#pragma clang diagnostic pop
    }
}

- (NSUInteger)kb_totalKeyButtonCount {
    NSUInteger total = 0;
    for (UIView *row in self.rowViews) {
        total += [self.interactionHandler collectKeyButtonsInView:row].count;
    }
    return total;
}

#pragma mark - Hit Test

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
    UIView *hit = [super hitTest:point withEvent:event];
    return [self.interactionHandler resolveHitView:hit
                                             point:point
                                         container:self
                                          rowViews:self.rowViews];
}

#pragma mark - Config Helpers

- (KBKeyboardLayoutConfig *)kb_layoutConfig {
    if (!self.layoutConfig) {
        self.layoutConfig = [KBKeyboardLayoutConfig sharedConfig];
    }
    return self.layoutConfig;
}

- (KBKeyboardKeyFactory *)keyFactory {
    if (!_keyFactory) {
        _keyFactory = [[KBKeyboardKeyFactory alloc] initWithLayoutConfig:[self kb_layoutConfig]];
    }
    return _keyFactory;
}

- (KBKeyboardLayoutEngine *)layoutEngine {
    if (!_layoutEngine) {
        _layoutEngine = [[KBKeyboardLayoutEngine alloc] initWithLayoutConfig:[self kb_layoutConfig]];
    }
    return _layoutEngine;
}

- (KBKeyboardRowBuilder *)rowBuilder {
    if (!_rowBuilder) {
        _rowBuilder = [[KBKeyboardRowBuilder alloc] initWithLayoutConfig:[self kb_layoutConfig]
                                                           layoutEngine:self.layoutEngine
                                                             keyFactory:self.keyFactory];
    }
    return _rowBuilder;
}

- (KBKeyboardInputHandler *)inputHandler {
    if (!_inputHandler) {
        _inputHandler = [[KBKeyboardInputHandler alloc] init];
        __weak typeof(self) weakSelf = self;
        _inputHandler.onToggleShift = ^{
            __strong typeof(weakSelf) self = weakSelf;
            if (!self) { return; }
            self.shiftOn = !self.shiftOn;
            [self reloadKeys];
        };
        _inputHandler.onToggleSymbols = ^{
            __strong typeof(weakSelf) self = weakSelf;
            if (!self) { return; }
            self.symbolsMoreOn = !self.symbolsMoreOn;
            [self reloadKeys];
        };
        _inputHandler.onKeyTapped = ^(KBKey *key) {
            __strong typeof(weakSelf) self = weakSelf;
            if (!self) { return; }
            if ([self.delegate respondsToSelector:@selector(keyboardView:didTapKey:)]) {
                [self.delegate keyboardView:self didTapKey:key];
            }
        };
    }
    return _inputHandler;
}

- (KBKeyboardLegacyBuilder *)legacyBuilder {
    if (!_legacyBuilder) {
        _legacyBuilder = [[KBKeyboardLegacyBuilder alloc] init];
    }
    return _legacyBuilder;
}

- (KBKeyboardLegacyLayoutProvider *)legacyLayoutProvider {
    if (!_legacyLayoutProvider) {
        _legacyLayoutProvider = [[KBKeyboardLegacyLayoutProvider alloc] init];
    }
    return _legacyLayoutProvider;
}

- (KBKeyboardInteractionHandler *)interactionHandler {
    if (!_interactionHandler) {
        _interactionHandler = [[KBKeyboardInteractionHandler alloc] init];
    }
    return _interactionHandler;
}

- (KBKeyboardRowContainerBuilder *)rowContainerBuilder {
    if (!_rowContainerBuilder) {
        _rowContainerBuilder = [[KBKeyboardRowContainerBuilder alloc] init];
    }
    return _rowContainerBuilder;
}

- (KBKeyboardLayout *)kb_layoutForName:(NSString *)name {
    return [[self kb_layoutConfig] layoutForName:name];
}

- (KBKeyboardLayout *)kb_currentLayout {
    NSString *baseLayoutName = self.currentLayoutJsonId.length > 0 ? self.currentLayoutJsonId : @"letters";
    
    if (self.layoutStyle == KBKeyboardLayoutStyleNumbers) {
        // 优先查找当前语言的数字/符号布局，如 letters_es_numbers / letters_es_symbols
        // 如果不存在，回退到通用布局 numbers / symbolsMore
        NSString *numbersName = [NSString stringWithFormat:@"%@_numbers", baseLayoutName];
        NSString *symbolsName = [NSString stringWithFormat:@"%@_symbols", baseLayoutName];
        NSString *targetName = self.symbolsMoreOn ? symbolsName : numbersName;
        
        KBKeyboardLayout *layout = [self kb_layoutForName:targetName];
        if (layout && layout.rows.count >= 4) {
            return layout;
        }
        // 回退到通用布局
        return [self kb_layoutForName:(self.symbolsMoreOn ? @"symbolsMore" : @"numbers")];
    }
    
    return [self kb_layoutForName:baseLayoutName];
}

- (void)reloadLayoutWithProfileId:(NSString *)profileId {
    if (profileId.length == 0) {
        NSLog(@"[KBKeyboardView] reloadLayoutWithProfileId: empty profileId, ignoring");
        return;
    }

    NSString *newLayoutJsonId = [[KBKeyboardLayoutResolver sharedResolver] layoutJsonIdForProfileId:profileId];
    if ([newLayoutJsonId isEqualToString:self.currentLayoutJsonId]) {
        NSLog(@"[KBKeyboardView] Layout already loaded: %@", newLayoutJsonId);
        return;
    }

    NSLog(@"[KBKeyboardView] Switching layout from %@ to %@", self.currentLayoutJsonId, newLayoutJsonId);
    self.currentLayoutJsonId = newLayoutJsonId;

    // 重新加载键盘布局
    [self reloadKeys];
}

- (void)kb_buildLegacyLayout {
    self.keysForRows = [self.legacyLayoutProvider keysForLayoutStyleIsNumbers:(self.layoutStyle == KBKeyboardLayoutStyleNumbers)
                                                                     shiftOn:self.shiftOn
                                                                symbolsMoreOn:self.symbolsMoreOn
                                                                   keyFactory:self.keyFactory];
    if (self.keysForRows.count < 4) { return; }
    if (self.rowViews.count < 4) { return; }

    [self.legacyBuilder buildRow:self.rowViews[0]
                        withKeys:self.keysForRows[0]
            edgeSpacerMultiplier:0.0
                         shiftOn:self.shiftOn
                 backspaceHandler:self.backspaceHandler
                           target:self
                           action:@selector(onKeyTapped:)];

    CGFloat row2Spacer = (self.layoutStyle == KBKeyboardLayoutStyleLetters)
                         ? kKBLettersRow2EdgeSpacerMultiplier : 0.0;
    [self.legacyBuilder buildRow:self.rowViews[1]
                        withKeys:self.keysForRows[1]
            edgeSpacerMultiplier:row2Spacer
                         shiftOn:self.shiftOn
                 backspaceHandler:self.backspaceHandler
                           target:self
                           action:@selector(onKeyTapped:)];

    [self.legacyBuilder buildRow:self.rowViews[2]
                        withKeys:self.keysForRows[2]
            edgeSpacerMultiplier:0.0
                         shiftOn:self.shiftOn
                 backspaceHandler:self.backspaceHandler
                           target:self
                           action:@selector(onKeyTapped:)];
    [self.legacyBuilder buildRow:self.rowViews[3]
                        withKeys:self.keysForRows[3]
            edgeSpacerMultiplier:0.0
                         shiftOn:self.shiftOn
                 backspaceHandler:self.backspaceHandler
                           target:self
                           action:@selector(onKeyTapped:)];
}

#pragma mark - Actions

- (void)onKeyTapped:(KBKeyButton *)sender {
    [self.inputHandler handleKeyTap:sender.key];
}

// 在字符键按下时，显示一个上方气泡预览（类似系统键盘）。
- (void)showPreviewForButton:(KBKeyButton *)button {
    [self.interactionHandler showPreviewForButton:button inContainer:self];
}

- (void)hidePreview {
    [self.interactionHandler hidePreview];
}

#pragma mark - Lazy

- (NSMutableArray<UIView *> *)rowViews {
    if (!_rowViews) _rowViews = [NSMutableArray array];
    return _rowViews;
}

@end