// useAudioSpeak.js
import { ref } from 'vue'
import globalConfig from '@/config.js';
import useUserStore from '@/stores/useUserStore';

/**
 * TTS语音合成Hook (队列播放版本)
 * @param {Object} config - TTS配置
 * @param {string} config.apiUrl - 语音合成API地址
 * @param {number} config.maxSegmentLength - 最大分段长度
 * @param {number} config.minQueueSize - 最小队列缓存数量
 * @param {number} config.maxRetry - 最大重试次数
 * @returns {Object} TTS相关方法和状态
 */
export const useAudioSpeak = (config = {}) => {
  const {
    apiUrl = `${globalConfig.baseUrl}/app/speech/tts`,
    maxSegmentLength = 30,
    minQueueSize = 3, // 最小队列缓存数量
    maxRetry = 2, // 最大重试次数
    onStatusChange = () => {} // 状态变化回调
  } = config

  // 状态
  const isSpeaking = ref(false)
  const isPaused = ref(false)
  const isLoading = ref(false)
  
  // 播放状态
  const currentText = ref('')
  const currentSegmentIndex = ref(0)
  const totalSegments = ref(0)
  const progress = ref(0)
  
  // 队列容器
  let textQueue = [] // 等待转换的文本队列 [{text, index}]
  let audioQueue = [] // 已经转换好的音频队列 [{blobUrl, text, index}]
  
  // 控制标志
  let isFetching = false // 是否正在请求音频
  let isPlaying = false // 是否正在播放（逻辑状态）
  let currentPlayingIndex = -1 // 当前正在播放的片段索引
  let audioContext = null
  let audioSource = null
  let currentAudioUrl = '' // 当前播放的音频URL
  
  // 文本提取工具函数
  function extractSpeechText(markdown) {
    if (!markdown || markdown.indexOf('job-json') === -1) {
      return markdown;
    }
    const jobRegex = /``` job-json\s*({[\s\S]*?})\s*```/g;
    const jobs = [];
    let match;
    let lastJobEndIndex = 0;
    let firstJobStartIndex = -1;

    while ((match = jobRegex.exec(markdown)) !== null) {
      const jobStr = match[1];
      try {
        const job = JSON.parse(jobStr);
        jobs.push(job);
        if (firstJobStartIndex === -1) {
          firstJobStartIndex = match.index;
        }
        lastJobEndIndex = jobRegex.lastIndex;
      } catch (e) {
        console.warn('JSON 解析失败', e);
      }
    }

    const guideText = firstJobStartIndex > 0 ?
      markdown.slice(0, firstJobStartIndex).trim() : '';
    const endingText = lastJobEndIndex < markdown.length ?
      markdown.slice(lastJobEndIndex).trim() : '';

    const jobTexts = jobs.map((job, index) => {
      // 处理薪资格式
      let salaryText = job.salary;
      if (salaryText) {
        // 匹配 "XXXXX-XXXXX元/月" 格式
        const rangeMatch = salaryText.match(/(\d+)-(\d+)元\/月/);
        if (rangeMatch) {
          const minSalary = parseInt(rangeMatch[1], 10);
          const maxSalary = parseInt(rangeMatch[2], 10);
          
          // 转换为千位单位
          const minK = Math.round(minSalary / 1000);
          const maxK = Math.round(maxSalary / 1000);

          salaryText = `${minK}千到${maxK}千每月`;
        }
        // 如果不是 "XXXXX-XXXXX元/月" 格式，保持原样
      }

      return `第 ${index + 1} 个岗位，岗位名称是：${job.jobTitle}，公司是：${job.companyName}，薪资：${salaryText}，地点：${job.location}，学历要求：${job.education}，经验要求：${job.experience}。`;
    });

    const finalTextParts = [];
    if (guideText) finalTextParts.push(guideText);
    finalTextParts.push(...jobTexts);
    if (endingText) finalTextParts.push(endingText);

    return finalTextParts.join('\n');
  }

  /**
   * 智能文本切割
   * 作用：合并短句减少请求次数，切分长句避免超时
   */
  const _smartSplit = (text) => {
    if (!text || typeof text !== 'string') return [];
    
    const cleanText = text.replace(/\s+/g, ' ').trim();
    
    // 先按标点粗分
    const rawChunks = cleanText.split(/([。？！；\n\r]|……)/).filter((t) => t.trim());
    const mergedChunks = [];
    let temp = '';

    for (let i = 0; i < rawChunks.length; i++) {
      const part = rawChunks[i];
      // 如果是标点，追加到上一句
      if (/^[。？！；\n\r……]$/.test(part)) {
        temp += part;
      } else {
        // 如果当前积累的句子太长（超过50字），先推入队列
        if (temp.length > 50) {
          mergedChunks.push(temp);
          temp = part;
        } else if (temp.length + part.length < 15) {
          // 如果当前积累的太短（少于15字），则合并下一句
          temp += part;
        } else {
          // 正常长度，推入
          if (temp) mergedChunks.push(temp);
          temp = part;
        }
      }
    }
    if (temp) mergedChunks.push(temp);
    
    // 如果还有超过 maxSegmentLength 的，强制分割
    const finalSegments = [];
    mergedChunks.forEach(segment => {
      if (segment.length <= maxSegmentLength) {
        finalSegments.push(segment);
      } else {
        // 按字数强制分割
        for (let i = 0; i < segment.length; i += maxSegmentLength) {
          finalSegments.push(segment.substring(i, Math.min(i + maxSegmentLength, segment.length)));
        }
      }
    });
    
    return finalSegments.filter(seg => seg && seg.trim());
  }

  /**
   * 统一状态通知
   */
  const _updateState = (state = {}) => {
    // 合并当前状态供 UI 使用
    const payload = {
      isPlaying: isPlaying,
      isPaused: isPaused.value,
      isLoading: state.isLoading || false,
      msg: state.msg || '',
      currentSegmentIndex: currentSegmentIndex.value,
      totalSegments: totalSegments.value,
      progress: progress.value
    };
    
    // 更新响应式状态
    isLoading.value = state.isLoading || false;
    
    // 调用回调
    onStatusChange(payload);
  }

  /**
   * 网络请求包装 (带重试机制)
   */
  const _fetchAudioWithRetry = async (text, retries = 0) => {
    try {
      console.log(`📶正在请求音频: "${text}"`);

      let Authorization = '';
      if (useUserStore().token) {
        Authorization = `${useUserStore().token}`;
      }

      const response = await fetch(`${apiUrl}?text=${encodeURIComponent(text)}`, {
        method: 'GET',
        headers: {
          'Content-Type': 'application/json',
          'Authorization': encodeURIComponent(Authorization)
        }
      });
      
      if (!response.ok) {
        throw new Error(`HTTP错误! 状态码: ${response.status}`);
      }
      
      const audioBlob = await response.blob();
      
      if (!audioBlob || audioBlob.size < 100) {
        throw new Error('音频数据太小或无效');
      }
      
      console.log(`音频获取成功，大小: ${audioBlob.size} 字节`);
      
      // 创建Blob URL
      return URL.createObjectURL(audioBlob);
      
    } catch (e) {
      if (retries < maxRetry) {
        console.warn(`重试 ${retries + 1} 次，文本: ${text.substring(0, 10)}...`);
        return await _fetchAudioWithRetry(text, retries + 1);
      }
      throw e;
    }
  }

  /**
   * 缓冲维护器 (生产者)
   * 始终保持 audioQueue 里有足够的音频
   */
  const _maintainBuffer = async () => {
    // 如果正在请求，或 文本队列没了，或 音频缓冲已达标，则停止请求
    if (isFetching || textQueue.length === 0) {
      return;
    }

    // 缓冲策略：如果音频队列里的数量少于 minQueueSize，就继续下载
    if (audioQueue.length >= minQueueSize) {
      return;
    }

    isFetching = true;
    const textItem = textQueue.shift(); // 从文本队列取出

    try {
      const blobUrl = await _fetchAudioWithRetry(textItem.text);
      audioQueue.push({ 
        blobUrl, 
        text: textItem.text, 
        index: textItem.index 
      });

      console.log(`音频已添加到队列，当前队列长度: ${audioQueue.length}`);

      // 如果当前因为没音频卡住了（Loading状态），立即尝试播放下一段
      if (!audioSource && !isPaused.value && isPlaying) {
        _playNext();
      }
    } catch (error) {
      console.error('缓冲维护失败:', error);
      // 即使失败，也要继续处理下一个文本，防止死锁
    } finally {
      isFetching = false;
      // 递归调用：继续检查是否需要填充缓冲
      _maintainBuffer();
    }
  }

  /**
   * 初始化音频上下文
   */
  const initAudioContext = () => {
    if (!audioContext || audioContext.state === 'closed') {
      audioContext = new (window.AudioContext || window.webkitAudioContext)();
      console.log('音频上下文已初始化');
    }
    return audioContext;
  }

  /**
   * 播放控制器 (消费者)
   */
  const _playNext = () => {
    if (!isPlaying || isPaused.value) {
      return;
    }

    // 尝试从缓冲队列获取下一个应该播放的片段
    const nextIndex = currentPlayingIndex + 1;
    const itemIndex = audioQueue.findIndex(item => item.index === nextIndex);

    // 1. 缓冲耗尽：进入"加载中"等待状态
    if (itemIndex === -1) {
      if (textQueue.length === 0 && !isFetching) {
        // 彻底播完了
        console.log('所有音频播放完成');
        stopAudio();
        _updateState({ isPlaying: false, msg: '播放结束' });
      } else {
        // 还有文本没转完，说明网速慢了，正在缓冲
        _updateState({ isLoading: true, msg: '缓冲中...' });
        // 确保生产线在运行
        _maintainBuffer();
      }
      return;
    }

    // 2. 正常播放
    const item = audioQueue.splice(itemIndex, 1)[0];
    
    // 释放上一段的内存
    if (currentAudioUrl) {
      URL.revokeObjectURL(currentAudioUrl);
      currentAudioUrl = '';
    }

    currentPlayingIndex = item.index;
    currentSegmentIndex.value = item.index;
    currentAudioUrl = item.blobUrl;

    // 更新进度
    if (totalSegments.value > 0) {
      progress.value = Math.floor(((item.index + 1) / totalSegments.value) * 100);
    }

    _updateState({ 
      isLoading: false, 
      msg: `播放中: ${item.text.substring(0, 15)}...` 
    });

    // 播放音频
    _playAudio(item.blobUrl, item.text, item.index);
    
    // 消费了一个，通知生产者补充库存
    _maintainBuffer();
  }

  /**
   * 播放音频
   */
  const _playAudio = async (blobUrl, text, index) => {
    return new Promise((resolve, reject) => {
      if (!isPlaying || isPaused.value) {
        resolve();
        return;
      }

      initAudioContext();
      
      const fileReader = new FileReader();
      
      fileReader.onload = async (e) => {
        try {
          const arrayBuffer = e.target.result;
          const audioBuffer = await audioContext.decodeAudioData(arrayBuffer);
          
          // 如果在此期间被暂停或停止，直接返回
          if (!isPlaying || isPaused.value) {
            resolve();
            return;
          }
          
          audioSource = audioContext.createBufferSource();
          audioSource.buffer = audioBuffer;
          audioSource.connect(audioContext.destination);
          
          audioSource.onended = () => {
            console.log(`第${index + 1}个片段播放完成`);
            audioSource = null;
            
            // 播放下一段
            _playNext();
            resolve();
          };
          
          audioSource.onerror = (error) => {
            console.error('音频播放错误:', error);
            audioSource = null;
            
            // 跳过错误片段，尝试下一段
            setTimeout(() => {
              _playNext();
            }, 100);
            reject(error);
          };
          
          console.log(`▶️开始播放第${index + 1}个片段: "${text}`);
          
          // 如果音频上下文被暂停，先恢复
          if (audioContext.state === 'suspended') {
            await audioContext.resume();
          }
          
          audioSource.start(0);
          
        } catch (error) {
          console.error('解码或播放音频失败:', error);
          audioSource = null;
          
          // 跳过错误片段，尝试下一段
          setTimeout(() => {
            _playNext();
          }, 100);
          reject(error);
        }
      };
      
      fileReader.onerror = (error) => {
        console.error('读取音频文件失败:', error);
        audioSource = null;
        
        // 跳过错误片段，尝试下一段
        setTimeout(() => {
          _playNext();
        }, 100);
        reject(error);
      };
      
      // 先获取Blob，再读取
      fetch(blobUrl)
        .then(response => response.blob())
        .then(blob => {
          fileReader.readAsArrayBuffer(blob);
        })
        .catch(error => {
          console.error('获取Blob失败:', error);
          reject(error);
        });
    });
  }

  /**
   * 核心入口：开始播放长文本
   */
  const speak = async (text) => {
    console.log('开始新的语音播报');
    

      cleanup();
      // 等待一小段时间确保资源清理完成
      await new Promise(resolve => setTimeout(resolve, 200));

    
    text = extractSpeechText(text);
    console.log('开始语音播报:', text);
    
    // 重置状态
    isPlaying = true;
    isPaused.value = false;
    isLoading.value = true;
    isSpeaking.value = true;
    
    currentText.value = text;
    progress.value = 0;
    currentPlayingIndex = -1;
    currentSegmentIndex.value = 0;
    
    // 清空队列
    textQueue = [];
    audioQueue = [];
    
    // 清理之前的Blob URL
    if (currentAudioUrl) {
      URL.revokeObjectURL(currentAudioUrl);
      currentAudioUrl = '';
    }
    
    // 1. 智能切割文本
    const segments = _smartSplit(text);
    console.log('文本分段结果:', segments);
    
    if (segments.length === 0) {
      console.warn('没有有效的文本可以播报');
      _updateState({ isPlaying: false, msg: '没有有效的文本' });
      isSpeaking.value = false;
      isLoading.value = false;
      return;
    }
    
    totalSegments.value = segments.length;
    
    // 2. 填充文本队列
    segments.forEach((segment, index) => {
      textQueue.push({ text: segment, index });
    });
    
    _updateState({ isLoading: true, msg: '初始化播放...' });
    
    // 3. 启动"缓冲流水线"
    _maintainBuffer();
    
    // 4. 开始播放
    setTimeout(() => {
      _playNext();
    }, 100);
  }

  /**
   * 暂停播放
   */
  const pause = () => {
    if (isPlaying && !isPaused.value) {
      isPaused.value = true;
      
      if (audioContext) {
        audioContext.suspend().then(() => {
          _updateState({ isPaused: true, msg: '已暂停' });
        });
      } else {
        _updateState({ isPaused: true, msg: '已暂停' });
      }
    }
  }

  /**
   * 恢复播放
   */
  const resume = () => {
    
    if (isPlaying && isPaused.value) {
      isPaused.value = false;
      
      // 恢复播放。如果当前有音频源则直接resume，否则调_playNext
      if (audioContext && audioContext.state === 'suspended') {
        audioContext.resume().then(() => {
          _updateState({ isPaused: false, msg: '继续播放' });
        });
      } else if (audioSource) {
        _updateState({ isPaused: false, msg: '继续播放' });
      } else {
        _playNext();
      }
    }
  }

  /**
   * 停止播放
   */
  const stopAudio = () => {
    console.log('停止音频播放');
    
    isPlaying = false;
    isPaused.value = false;
    isFetching = false;
    isSpeaking.value = false;
    isLoading.value = false;
    
    // 停止音频源
    if (audioSource) {
      try {
        audioSource.stop();
        console.log('音频源已停止');
      } catch (e) {
        console.warn('停止音频源失败:', e);
      }
      audioSource = null;
    }
    
    // 暂停音频上下文
    if (audioContext && audioContext.state !== 'closed') {
      audioContext.suspend();
    }
    
    // 清理所有 Blob 内存
    if (currentAudioUrl) {
      URL.revokeObjectURL(currentAudioUrl);
      currentAudioUrl = '';
    }
    
    // 清理音频队列中的Blob URL
    audioQueue.forEach(item => {
      if (item.blobUrl) {
        URL.revokeObjectURL(item.blobUrl);
      }
    });
    
    // 清空队列
    textQueue = [];
    audioQueue = [];
    
    currentPlayingIndex = -1;
    progress.value = 0;
    
    _updateState({ isPlaying: false, msg: '已停止' });
  }

  /**
   * 清理资源
   */
  const cleanup = () => {
    console.log('开始清理资源');
    stopAudio();
    
    if (audioContext && audioContext.state !== 'closed') {
      audioContext.close();
      console.log('音频上下文已关闭');
    }
    
    audioContext = null;
    console.log('资源清理完成');
  }

  return {
    // 状态
    isSpeaking,
    isPaused,
    isLoading,
    currentText,
    currentSegmentIndex,
    totalSegments,
    progress,
    
    // 方法
    speak,
    pause,
    resume,
    cancelAudio: stopAudio,
    cleanup
  }
}