// 语音识别类
class VoiceRecognition {
    constructor() {
        this.recognition = null;
        this.isListening = false;
        this.isSupported = false;
        this.onResult = null;
        this.onError = null;
        this.onStatusChange = null;
        
        // 错误重试控制
        this.retryCount = 0;
        this.maxRetries = 3;
        this.retryDelay = 2000; // 2秒延迟
        this.lastErrorTime = 0;
        this.consecutiveErrors = 0;
        this.isDisabled = false;
        
        // 新增：防止并发启动的锁机制
        this.isStarting = false;
        this.isStopping = false;
        this.restartTimer = null;
        this.startupPromise = null;
        
        // 双击恢复功能标志
        this.doubleClickRecoveryAdded = false;
        
        this.init();
    }
    
    init() {
        // 检查浏览器支持
        if ('webkitSpeechRecognition' in window) {
            this.recognition = new webkitSpeechRecognition();
            this.isSupported = true;
        } else if ('SpeechRecognition' in window) {
            this.recognition = new SpeechRecognition();
            this.isSupported = true;
        } else {
            console.warn('浏览器不支持语音识别');
            this.handleError('浏览器不支持语音识别');
            return;
        }
        
        this.setupRecognition();
        
        // 使用更安全的异步启动
        setTimeout(async () => {
            try {
                console.log('初始化语音识别...');
                await this.startListening();
            } catch (error) {
                console.error('初始化启动失败:', error);
                // 如果初始化失败，给用户提供恢复选项
                setTimeout(() => {
                    this.showNotification('语音识别初始化遇到问题，双击页面重新尝试', 'warning');
                    this.addDoubleClickRecovery();
                }, 2000);
            }
        }, 500); // 增加初始化延迟
    }
    
    setupRecognition() {
        // 配置语音识别
        this.recognition.continuous = true;
        this.recognition.interimResults = false;
        this.recognition.lang = 'en-US'; // 使用英文识别食物名称
        this.recognition.maxAlternatives = 3;
        
        // 事件监听
        this.recognition.onstart = () => {
            this.isListening = true;
            this.updateStatus('listening');
            console.log('语音识别开始');
        };
        
        this.recognition.onresult = (event) => {
            this.handleResult(event);
        };
        
        this.recognition.onerror = (event) => {
            this.handleError(event.error);
        };
        
        this.recognition.onend = () => {
            this.isListening = false;
            this.isStopping = false;
            this.updateStatus('ready');
            console.log('语音识别结束');
            
            // 清除之前的重启定时器
            if (this.restartTimer) {
                clearTimeout(this.restartTimer);
                this.restartTimer = null;
            }
            
            // 智能重启逻辑 - 避免在错误频发时无限重试
            if (this.shouldAttemptRestart()) {
                const delay = this.calculateRestartDelay();
                console.log(`准备在 ${delay}ms 后重新启动语音识别...`);
                
                this.restartTimer = setTimeout(async () => {
                    if (this.isSupported && !this.isListening && !this.isDisabled && !this.isStarting) {
                        await this.startListening();
                    }
                }, delay);
            } else {
                console.log('由于频繁错误，暂停自动重启语音识别');
                this.showNotification('语音识别暂停，请点击页面重新激活或使用键盘输入（F9）', 'warning');
            }
        };
    }
    
    handleResult(event) {
        this.updateStatus('processing');
        
        let finalTranscript = '';
        let interimTranscript = '';
        let confidence = 0;
        
        // 处理识别结果
        for (let i = event.resultIndex; i < event.results.length; i++) {
            const transcript = event.results[i][0].transcript;
            confidence = event.results[i][0].confidence || 0;
            
            if (event.results[i].isFinal) {
                finalTranscript += transcript;
            } else {
                interimTranscript += transcript;
            }
        }
        
        // 显示实时语音输入
        const currentText = finalTranscript || interimTranscript;
        if (currentText) {
            this.showVoiceInput(currentText, confidence, !finalTranscript);
        }
        
        // 如果有最终结果，触发回调
        if (finalTranscript && this.onResult) {
            console.log('语音识别结果:', finalTranscript);
            this.onResult(finalTranscript.trim());
            
            // 短暂显示识别成功状态
            setTimeout(() => {
                this.hideVoiceInput();
            }, 2000);
        }
        
        this.updateStatus('ready');
    }
    
    handleError(error) {
        console.error('语音识别错误:', error);
        this.updateStatus('error');
        
        // no-speech不算作真正的错误，不影响错误计数
        if (error !== 'no-speech') {
            // 记录错误时间和连续错误次数
            const now = Date.now();
            if (now - this.lastErrorTime < 5000) { // 5秒内的错误视为连续错误
                this.consecutiveErrors++;
            } else {
                this.consecutiveErrors = 1;
            }
            this.lastErrorTime = now;
        }
        
        if (this.onError) {
            this.onError(error);
        }
        
        // 根据错误类型处理
        switch (error) {
            case 'not-allowed':
                this.showPermissionError();
                this.isDisabled = true; // 禁用自动重启
                break;
            case 'no-speech':
                // 没有检测到语音是正常现象，不需要任何特殊处理
                console.log('没有检测到语音（正常状态）- 继续监听');
                
                // no-speech是正常状态，语音识别会自动继续运行
                // 不需要重启、不需要延迟、不需要任何额外操作
                break;
            case 'network':
                this.showNetworkError();
                console.log('网络错误，准备重试...');
                if (this.consecutiveErrors < 5) { // 网络问题容忍度适中
                    const delay = Math.min(3000 + (this.consecutiveErrors * 2000), 15000);
                    setTimeout(async () => {
                        if (this.isSupported && !this.isDisabled && !this.isListening) {
                            console.log('网络错误重试中...');
                            await this.safeRestart();
                        }
                    }, delay);
                } else {
                    this.showNotification('网络连接持续异常，语音识别已暂停。请检查网络后双击页面重启', 'error');
                    this.addDoubleClickRecovery();
                    this.isDisabled = true;
                }
                break;
            case 'aborted':
                this.handleAbortedError();
                break;
            default:
                // 其他错误，谨慎重试
                console.log(`未知错误类型: ${error}，准备重试...`);
                if (this.consecutiveErrors < 4) {
                    const delay = this.retryDelay * Math.pow(1.5, this.consecutiveErrors - 1);
                    setTimeout(async () => {
                        if (this.isSupported && !this.isDisabled && !this.isListening) {
                            console.log(`未知错误重试中（第${this.consecutiveErrors}次）...`);
                            await this.safeRestart();
                        }
                    }, delay);
                } else {
                    this.showNotification(`语音识别遇到未知错误：${error}。已暂停，双击页面重启`, 'error');
                    this.addDoubleClickRecovery();
                }
                break;
        }
    }
    
    handleAbortedError() {
        console.log('处理 aborted 错误，连续错误次数:', this.consecutiveErrors);
        
        // 更宽松的错误处理策略
        if (this.consecutiveErrors >= 5) {
            this.handleAbortedErrorLoop();
        } else {
            // 先完全清理当前状态
            this.forceCleanup();
            
            // 使用指数退避算法计算延迟时间
            const baseDelay = 2000;
            const delay = Math.min(baseDelay * Math.pow(2, this.consecutiveErrors - 1), 30000);
            console.log(`Aborted 错误（第${this.consecutiveErrors}次），${delay}ms 后重试`);
            
            // 添加状态检查的重试逻辑
            setTimeout(async () => {
                if (this.isSupported && !this.isDisabled && !this.isListening && !this.isStarting) {
                    console.log('重试启动语音识别...');
                    await this.safeRestart();
                } else {
                    console.log('跳过重试，当前状态不允许启动');
                }
            }, delay);
        }
    }
    
    handleAbortedErrorLoop() {
        console.warn('检测到 aborted 错误循环，暂停自动重启');
        this.isDisabled = true;
        
        // 显示更详细的错误信息和解决方案
        this.showNotification(
            '语音识别遇到连续错误已暂停。解决方案：\n' +
            '1. 按Ctrl+R刷新页面\n' +
            '2. 使用键盘输入（F9键）\n' +
            '3. 检查麦克风权限\n' +
            '4. 双击页面手动重启',
            'warning'
        );
        
        // 添加页面双击恢复功能
        this.addDoubleClickRecovery();
        
        // 减少自动恢复时间到2分钟，但保持更保守的重启策略
        setTimeout(() => {
            this.resetErrorState();
            this.showNotification('语音识别已重新启用，双击页面激活', 'info');
        }, 120000); // 2分钟
    }
    
    // 添加双击恢复功能
    addDoubleClickRecovery() {
        if (this.doubleClickRecoveryAdded) return;
        
        const handleDoubleClick = async (event) => {
            if (this.isDisabled) {
                console.log('用户双击恢复语音识别');
                this.showNotification('正在重启语音识别...', 'info');
                
                // 完全重置并重启
                this.resetErrorState();
                await this.forceCleanup();
                await new Promise(resolve => setTimeout(resolve, 1000));
                
                if (this.isSupported) {
                    try {
                        await this.startListening();
                        this.showNotification('语音识别已成功重启！', 'info');
                    } catch (error) {
                        this.showNotification('重启失败，请稍后再试或刷新页面', 'error');
                    }
                }
            }
        };
        
        document.addEventListener('dblclick', handleDoubleClick);
        this.doubleClickRecoveryAdded = true;
        
        console.log('已添加双击恢复功能');
    }
    
    shouldAttemptRestart() {
        // 判断是否应该尝试重启
        if (this.isDisabled) return false;
        if (this.consecutiveErrors >= 5) return false;
        
        return true;
    }
    
    calculateRestartDelay() {
        // 计算重启延迟时间
        let baseDelay = this.retryDelay;
        
        // 根据连续错误次数增加延迟
        const multiplier = Math.min(this.consecutiveErrors, 5);
        baseDelay *= multiplier;
        
        return Math.min(baseDelay, 30000); // 最大30秒
    }
    
    resetErrorState() {
        // 重置错误状态
        this.consecutiveErrors = 0;
        this.retryCount = 0;
        this.isDisabled = false;
        this.lastErrorTime = 0;
        console.log('错误状态已重置');
    }
    
    // 强制清理所有状态和资源
    forceCleanup() {
        console.log('执行强制清理...');
        
        // 清除所有定时器
        if (this.restartTimer) {
            clearTimeout(this.restartTimer);
            this.restartTimer = null;
        }
        
        if (this.hideTimer) {
            clearTimeout(this.hideTimer);
            this.hideTimer = null;
        }
        
        // 强制停止语音识别
        if (this.recognition) {
            try {
                this.recognition.abort();
            } catch (error) {
                console.log('强制停止时出错:', error);
            }
        }
        
        // 重置所有状态
        this.isListening = false;
        this.isStarting = false;
        this.isStopping = false;
        
        console.log('强制清理完成');
    }
    
    // 安全重启 - 带有更完善的状态检查
    async safeRestart() {
        console.log('执行安全重启...');
        
        try {
            // 1. 强制清理
            this.forceCleanup();
            
            // 2. 等待一段时间确保清理完成
            await new Promise(resolve => setTimeout(resolve, 1000));
            
            // 3. 状态验证
            if (this.isDisabled) {
                console.log('语音识别已禁用，取消重启');
                return;
            }
            
            if (this.isListening || this.isStarting) {
                console.log('语音识别状态异常，取消重启');
                return;
            }
            
            // 4. 重新初始化并启动
            if (this.recognition) {
                console.log('重新配置语音识别...');
                this.setupRecognition();
                await new Promise(resolve => setTimeout(resolve, 500));
                
                console.log('启动语音识别...');
                this.recognition.start();
                console.log('安全重启成功');
            }
            
        } catch (error) {
            console.error('安全重启失败:', error);
            this.consecutiveErrors++;
            
            // 如果安全重启也失败，增加更长的延迟后再试
            if (this.consecutiveErrors < 5) {
                setTimeout(() => this.safeRestart(), 5000);
            }
        }
    }
    
    async startListening() {
        if (!this.isSupported) {
            this.showUnsupportedError();
            return;
        }
        
        if (this.isDisabled) {
            console.log('语音识别已禁用，需要手动重启');
            return;
        }
        
        // 增强的并发控制
        if (this.isStarting) {
            console.log('语音识别正在启动中，等待完成...');
            // 等待当前启动完成
            let attempts = 0;
            while (this.isStarting && attempts < 10) {
                await new Promise(resolve => setTimeout(resolve, 500));
                attempts++;
            }
            if (this.isStarting) {
                console.error('启动超时，强制清理');
                this.forceCleanup();
            }
            return;
        }
        
        if (this.isListening) {
            console.log('语音识别已在运行中，跳过启动');
            return;
        }
        
        // 如果正在停止，等待停止完成
        if (this.isStopping) {
            console.log('等待停止完成后重新启动...');
            let stopAttempts = 0;
            while (this.isStopping && stopAttempts < 6) {
                await new Promise(resolve => setTimeout(resolve, 500));
                stopAttempts++;
            }
            if (this.isStopping) {
                console.log('停止超时，强制清理');
                this.forceCleanup();
            }
        }
        
        this.isStarting = true;
        console.log('开始启动语音识别...');
        
        try {
            // 1. 完全清理之前的状态
            await this.ensureFullyStoppedAsync();
            
            // 2. 额外的清理延迟
            await new Promise(resolve => setTimeout(resolve, 800));
            
            // 3. 最终状态检查
            if (this.isDisabled) {
                console.log('启动被取消：语音识别已禁用');
                return;
            }
            
            if (this.isListening) {
                console.log('启动被取消：语音识别已在运行');
                return;
            }
            
            // 4. 尝试启动
            console.log('尝试启动语音识别...');
            this.recognition.start();
            console.log('语音识别启动命令已发送');
            
        } catch (error) {
            console.error('启动语音识别失败:', error);
            
            // 特别处理常见错误
            if (error.toString().includes('already started')) {
                console.log('检测到重复启动错误，清理状态');
                this.forceCleanup();
            } else {
                this.handleError('start-failed');
            }
        } finally {
            // 延迟清除启动标志，确保onstart事件有时间触发
            setTimeout(() => {
                this.isStarting = false;
            }, 1000);
        }
    }
    
    // 确保语音识别完全停止
    async ensureFullyStoppedAsync() {
        if (!this.recognition) return;
        
        return new Promise((resolve) => {
            if (!this.isListening) {
                resolve();
                return;
            }
            
            this.isStopping = true;
            
            // 设置停止完成监听器
            const onStopComplete = () => {
                this.recognition.removeEventListener('end', onStopComplete);
                this.isStopping = false;
                this.isListening = false;
                console.log('语音识别已完全停止');
                resolve();
            };
            
            this.recognition.addEventListener('end', onStopComplete);
            
            // 强制停止
            try {
                this.recognition.abort();
            } catch (error) {
                console.log('停止时出现错误:', error);
                // 即使出错也要继续
                setTimeout(() => {
                    this.isStopping = false;
                    this.isListening = false;
                    resolve();
                }, 1000);
            }
            
            // 超时保护
            setTimeout(() => {
                if (this.isStopping) {
                    console.log('停止超时，强制完成');
                    this.recognition.removeEventListener('end', onStopComplete);
                    this.isStopping = false;
                    this.isListening = false;
                    resolve();
                }
            }, 3000);
        });
    }
    
    async stopListening() {
        if (this.recognition && this.isListening) {
            console.log('停止语音识别...');
            // 清除重启定时器
            if (this.restartTimer) {
                clearTimeout(this.restartTimer);
                this.restartTimer = null;
            }
            
            await this.ensureFullyStoppedAsync();
        }
    }
    
    // 重启语音识别
    async restart() {
        console.log('手动重启语音识别系统...');
        
        try {
            // 显示重启进度
            this.showNotification('正在重启语音识别...', 'info');
            
            // 1. 重置错误状态
            this.resetErrorState();
            
            // 2. 强制清理所有状态
            this.forceCleanup();
            
            // 3. 等待清理完成
            await new Promise(resolve => setTimeout(resolve, 1500));
            
            // 4. 检查支持状态
            if (!this.isSupported) {
                this.showNotification('当前浏览器不支持语音识别', 'error');
                return;
            }
            
            // 5. 重新初始化
            this.setupRecognition();
            await new Promise(resolve => setTimeout(resolve, 500));
            
            // 6. 启动语音识别
            if (!this.isDisabled) {
                console.log('执行重启...');
                await this.startListening();
                this.showNotification('语音识别已成功重启！', 'info');
            } else {
                this.showNotification('语音识别重启完成，但仍处于禁用状态', 'warning');
            }
            
        } catch (error) {
            console.error('重启失败:', error);
            this.showNotification('重启失败，建议刷新页面重试', 'error');
            
            // 重启失败时的降级方案
            this.resetErrorState();
        }
    }
    
    // 手动激活语音识别（用于用户点击按钮）
    async manualActivate() {
        console.log('手动激活语音识别');
        this.resetErrorState();
        
        if (this.isSupported) {
            await this.startListening();
            this.showNotification('语音识别已激活', 'info');
        } else {
            this.showNotification('当前浏览器不支持语音识别', 'error');
        }
    }
    
    // 永久禁用语音识别
    disable() {
        console.log('禁用语音识别');
        this.isDisabled = true;
        
        if (this.recognition && this.isListening) {
            this.recognition.abort();
        }
        
        this.showNotification('语音识别已禁用', 'warning');
    }
    
    // 启用语音识别
    async enable() {
        console.log('启用语音识别');
        this.resetErrorState();
        
        if (this.isSupported) {
            this.showNotification('语音识别已启用', 'info');
            await this.startListening();
        }
    }
    
    updateStatus(status) {
        if (this.onStatusChange) {
            this.onStatusChange(status);
        }
    }
    
    showVoiceInput(text, confidence = 0, isInterim = false) {
        const voiceDisplay = document.getElementById('voiceInputDisplay');
        const speechText = document.getElementById('speechText');
        const speechConfidence = document.getElementById('speechConfidence');
        const speechBubble = voiceDisplay.querySelector('.speech-bubble');
        
        if (!voiceDisplay || !speechText) return;
        
        // 显示语音输入框
        voiceDisplay.style.display = 'block';
        
        // 更新文本内容
        speechText.textContent = text;
        
        // 显示置信度
        if (confidence > 0) {
            speechConfidence.textContent = `置信度: ${Math.round(confidence * 100)}%`;
        } else {
            speechConfidence.textContent = isInterim ? '正在识别...' : '';
        }
        
        // 更新样式状态
        speechBubble.className = 'speech-bubble';
        if (isInterim) {
            speechBubble.classList.add('listening');
        } else {
            speechBubble.classList.add('recognized');
        }
        
        // 清除之前的隐藏定时器
        if (this.hideTimer) {
            clearTimeout(this.hideTimer);
        }
        
        // 如果是临时结果，设置自动隐藏
        if (isInterim) {
            this.hideTimer = setTimeout(() => {
                this.hideVoiceInput();
            }, 3000);
        }
    }
    
    hideVoiceInput() {
        const voiceDisplay = document.getElementById('voiceInputDisplay');
        if (voiceDisplay) {
            voiceDisplay.style.display = 'none';
        }
        
        if (this.hideTimer) {
            clearTimeout(this.hideTimer);
            this.hideTimer = null;
        }
    }
    
    showPermissionError() {
        this.showNotification('需要麦克风权限才能使用语音功能', 'error');
    }
    
    showNetworkError() {
        this.showNotification('网络连接错误，语音识别暂时不可用', 'error');
    }
    
    showUnsupportedError() {
        this.showNotification('您的浏览器不支持语音识别功能', 'error');
    }
    
    showNotification(message, type = 'info') {
        // 创建通知元素
        const notification = document.createElement('div');
        notification.className = `voice-notification ${type}`;
        notification.textContent = message;
        
        // 样式
        Object.assign(notification.style, {
            position: 'fixed',
            top: '20px',
            right: '20px',
            background: type === 'error' ? '#e74c3c' : '#4ecdc4',
            color: 'white',
            padding: '15px 20px',
            borderRadius: '10px',
            boxShadow: '0 4px 15px rgba(0,0,0,0.2)',
            zIndex: '10000',
            fontSize: '14px',
            maxWidth: '300px',
            animation: 'slideInRight 0.3s ease'
        });
        
        document.body.appendChild(notification);
        
        // 自动移除
        setTimeout(() => {
            notification.style.animation = 'slideOutRight 0.3s ease';
            setTimeout(() => {
                if (notification.parentNode) {
                    notification.parentNode.removeChild(notification);
                }
            }, 300);
        }, 5000);
    }
    
    // 测试语音识别功能
    test() {
        if (!this.isSupported) {
            console.log('语音识别不支持');
            return false;
        }
        
        console.log('语音识别测试开始...');
        
        // 设置测试回调
        const originalOnResult = this.onResult;
        this.onResult = (transcript) => {
            console.log('测试结果:', transcript);
            this.onResult = originalOnResult;
        };
        
        return true;
    }
    
    // 获取支持的语言列表
    getSupportedLanguages() {
        return [
            { code: 'en-US', name: 'English (US)' },
            { code: 'zh-CN', name: '中文 (普通话)' },
            { code: 'ja-JP', name: '日本語' },
            { code: 'ko-KR', name: '한국어' },
            { code: 'fr-FR', name: 'Français' },
            { code: 'de-DE', name: 'Deutsch' },
            { code: 'es-ES', name: 'Español' },
            { code: 'it-IT', name: 'Italiano' }
        ];
    }
    
    // 切换语言
    setLanguage(langCode) {
        if (this.recognition) {
            this.recognition.lang = langCode;
            console.log(`语音识别语言切换为: ${langCode}`);
        }
    }
    
    // 获取当前状态
    getStatus() {
        return {
            isSupported: this.isSupported,
            isListening: this.isListening,
            isDisabled: this.isDisabled,
            isStarting: this.isStarting,
            isStopping: this.isStopping,
            consecutiveErrors: this.consecutiveErrors,
            hasRestartTimer: !!this.restartTimer,
            currentLanguage: this.recognition ? this.recognition.lang : null,
            doubleClickRecoveryEnabled: this.doubleClickRecoveryAdded,
            healthStatus: this.getHealthStatus()
        };
    }
    
    // 获取系统健康状况
    getHealthStatus() {
        if (!this.isSupported) return 'unsupported';
        if (this.isDisabled) return 'disabled';
        if (this.consecutiveErrors >= 5) return 'critical';
        if (this.consecutiveErrors >= 3) return 'warning';
        if (this.isListening) return 'healthy';
        if (this.isStarting) return 'starting';
        return 'ready';
    }
    
    // 快速诊断和修复
    async quickFix() {
        console.log('执行快速诊断和修复...');
        
        const status = this.getHealthStatus();
        console.log('当前健康状况:', status);
        
        switch (status) {
            case 'unsupported':
                this.showNotification('浏览器不支持语音识别功能', 'error');
                return false;
                
            case 'disabled':
            case 'critical':
            case 'warning':
                console.log('检测到问题，执行完整重启...');
                await this.restart();
                return true;
                
            case 'starting':
                console.log('正在启动中，等待完成...');
                return true;
                
            case 'ready':
                console.log('系统就绪，尝试启动...');
                await this.startListening();
                return true;
                
            case 'healthy':
                console.log('系统运行正常');
                return true;
                
            default:
                console.log('未知状态，执行重启...');
                await this.restart();
                return true;
        }
    }
    
    // 清理所有资源和状态
    cleanup() {
        console.log('清理语音识别资源...');
        
        // 清除所有定时器
        if (this.restartTimer) {
            clearTimeout(this.restartTimer);
            this.restartTimer = null;
        }
        
        if (this.hideTimer) {
            clearTimeout(this.hideTimer);
            this.hideTimer = null;
        }
        
        // 停止语音识别
        if (this.recognition) {
            try {
                this.recognition.abort();
            } catch (error) {
                console.log('清理时停止识别出错:', error);
            }
        }
        
        // 重置状态
        this.isListening = false;
        this.isStarting = false;
        this.isStopping = false;
        this.isDisabled = true;
        
        console.log('语音识别资源清理完成');
    }
}

// 添加CSS动画
const style = document.createElement('style');
style.textContent = `
    @keyframes slideInRight {
        from {
            transform: translateX(100%);
            opacity: 0;
        }
        to {
            transform: translateX(0);
            opacity: 1;
        }
    }
    
    @keyframes slideOutRight {
        from {
            transform: translateX(0);
            opacity: 1;
        }
        to {
            transform: translateX(100%);
            opacity: 0;
        }
    }
    
    .voice-notification {
        font-family: 'Comic Neue', cursive;
        font-weight: bold;
        word-wrap: break-word;
    }
`;
document.head.appendChild(style);