/**
 * Microsoft Edge-TTS Provider（免费，基于 Edge 浏览器"大声朗读"引擎）
 *
 * 使用方式：通过 CLI 调用 edge-tts Python 包。
 * 安装依赖：pip install edge-tts
 *
 * 限制：
 *   - 单次最大 ~3000 字符（微软限制，实际按 bytes 算，中文约 1000 字安全）
 *   - 需 Python 3.8+ 环境
 *   - 依赖微软服务器，稳定性不如商业 API
 *
 * 音色文档：edge-tts --list-voices
 * 常用中文音色：
 *   zh-CN-XiaoxiaoNeural    — 女声，温柔自然（推荐）
 *   zh-CN-YunxiNeural       — 男声，标准播音
 *   zh-CN-YunyangNeural     — 男声，新闻风格
 *   zh-CN-XiaoyiNeural      — 女声，活泼
 *   zh-CN-YunjianNeural     — 男声，老成
 */

import { spawn } from 'child_process';
import fs from 'fs';
import path from 'path';
import { VoiceParams } from '../../types';
import { ITtsProvider } from './provider.interface';

// Edge-TTS 中文音色映射表（10个统一音色 + 附加音色）
const EDGE_VOICE_MAP: Record<string, string> = {
  // 统一 Voice ID → Edge-TTS 音色名（与 tts.service.ts 保持一致）
  voice_01: 'zh-CN-XiaoxiaoNeural',    // 温柔女声 → 晓晓
  voice_02: 'zh-CN-YunxiNeural',       // 磁性男声 → 云希
  voice_03: 'zh-CN-XiaoyiNeural',      // 活泼女声 → 晓依
  voice_04: 'zh-CN-YunyangNeural',     // 知性女声 → 云扬(新闻风格)
  voice_05: 'zh-CN-YunjianNeural',     // 阳光男声 → 云健
  voice_06: 'zh-CN-YunyangNeural',     // 沧桑男声 → 云扬
  voice_07: 'zh-CN-XiaoxiaoNeural',    // 甜美女声 → 晓晓
  voice_08: 'zh-CN-YunxiNeural',       // 清朗男声 → 云希
  voice_09: 'zh-CN-XiaoyiNeural',      // 亲切女声 → 晓依
  voice_10: 'zh-CN-XiaoshuangNeural',  // 稚嫩童声 → 晓双(童声)

  // 友好别名（也可以直接传 Edge 原生音色名）
  xiaoxiao: 'zh-CN-XiaoxiaoNeural',
  yunxi: 'zh-CN-YunxiNeural',
  xiaoyi: 'zh-CN-XiaoyiNeural',
  yunyang: 'zh-CN-YunyangNeural',
};

/** 将内部 Voice ID 映射到 Edge-TTS 音色名 */
function resolveVoice(voiceId: string): string {
  // 先查映射表
  if (EDGE_VOICE_MAP[voiceId]) return EDGE_VOICE_MAP[voiceId];
  // 如果已经是 Edge 原生格式（包含 Neural），直接使用
  if (voiceId.includes('Neural')) return voiceId;
  // 兜底：默认女声
  return 'zh-CN-XiaoxiaoNeural';
}

export class EdgeTtsProvider implements ITtsProvider {
  readonly name: string;
  readonly vendor = 'edge';
  readonly mode = 'sync' as const;
  readonly maxTextLength: number = 1000; // Edge-TTS 单次中文安全长度
  readonly concurrency = 2;
  readonly modelId: string;
  readonly ttsApiPath = ''; // 不需要 API 路径
  readonly defaultVoice: string;

  constructor(
    vendorKey: string = 'edge',
    _apiKey?: string, // Edge-TTS 无需 API Key
    modelId?: string,
    _ttsApiPath?: string,
    maxTextLength?: number,
  ) {
    this.name = `${vendorKey}-tts`;
    this.modelId = modelId || 'edge-tts';
    this.defaultVoice = 'zh-CN-XiaoxiaoNeural';
    if (maxTextLength) this.maxTextLength = maxTextLength;
  }

  async synthesize(
    text: string,
    voiceId: string,
    params: VoiceParams,
    outputPath: string,
  ): Promise<string> {
    const voice = resolveVoice(voiceId || this.defaultVoice);
    const dir = path.dirname(outputPath);
    if (!fs.existsSync(dir)) fs.mkdirSync(dir, { recursive: true });

    // 确保输出路径为 .mp3
    const finalPath = outputPath.endsWith('.mp3') ? outputPath : outputPath.replace(/\.[^.]+$/, '.mp3');

    const args = [
      '--voice', voice,
      '--text', text,
      '--write-media', finalPath,
    ];

    // 语速映射：speed 0.5~2.0 → rate -50%~+100%
    // 注意：使用 --rate=<value> 格式而非 --rate <value>，避免 shell 解析负值参数
    if (params.speed !== undefined && params.speed !== 1) {
      const ratePercent = Math.round((params.speed - 1) * 100);
      const sign = ratePercent > 0 ? '+' : '';
      args.push(`--rate=${sign}${ratePercent}%`);
    }

    // 音调映射：pitch -500~500 → pitch -50Hz~+50Hz
    if (params.pitch !== undefined && params.pitch !== 0) {
      const pitchHz = Math.round(params.pitch / 10);
      const sign = pitchHz > 0 ? '+' : '';
      args.push(`--pitch=${sign}${pitchHz}Hz`);
    }

    // 音量映射：volume 0~100 → -100%~+100%（默认50不调整）
    if (params.volume !== undefined && params.volume !== 50) {
      const volPercent = Math.round((params.volume / 50 - 1) * 100);
      if (volPercent !== 0) {
        const sign = volPercent > 0 ? '+' : '';
        args.push(`--volume=${sign}${volPercent}%`);
      }
    }

    console.log(`📢 [EdgeTTS] 开始合成: voice=${voice}, text=${text.length}字, output=${path.basename(finalPath)}`);

    const startTime = Date.now();

    return new Promise<string>((resolve, reject) => {
      // 优先用 edge-tts 命令（避免 python -m 解析长文本的 argparse 问题）
      // shell: false 避免 shell 解析带负号的参数（如 -20%）
      const edgeCmd = spawn('edge-tts', args, {
        shell: false,
        stdio: ['pipe', 'pipe', 'pipe'],
      });

      let stderr = '';
      let exited = false;

      edgeCmd.stderr.on('data', (chunk: Buffer) => {
        stderr += chunk.toString();
      });

      edgeCmd.on('error', (err) => {
        if (exited) return;
        exited = true;
        // 尝试 fallback：直接用 edge-tts 命令
        console.log(`⚠️ [EdgeTTS] python -m edge_tts 失败，尝试 edge-tts 命令: ${err.message}`);
        this.runEdgeTtsDirect(args, finalPath, startTime, resolve, reject);
      });

      edgeCmd.on('close', (code) => {
        if (exited) return;
        exited = true;

        if (code === 0 && fs.existsSync(finalPath)) {
          const stats = fs.statSync(finalPath);
          const elapsed = Date.now() - startTime;
          console.log(`✅ [EdgeTTS] 完成: ${finalPath} (${stats.size} bytes, ${elapsed}ms)`);
          resolve(finalPath);
        } else {
          // 如果 python -m 失败，尝试 edge-tts 命令
          if (stderr.toLowerCase().includes('no module') || code !== 0) {
            console.log(`⚠️ [EdgeTTS] python -m 返回 code=${code}，尝试 edge-tts 命令`);
            this.runEdgeTtsDirect(args, finalPath, startTime, resolve, reject);
          } else {
            reject(new Error(`EdgeTTS 合成失败 (code=${code}): ${stderr.substring(0, 200)}`));
          }
        }
      });
    });
  }

  /** Fallback：直接用 edge-tts 命令 */
  private runEdgeTtsDirect(
    args: string[],
    finalPath: string,
    startTime: number,
    resolve: (value: string) => void,
    reject: (error: Error) => void,
  ) {
    const child = spawn('edge-tts', args, {
      shell: false,
      stdio: ['pipe', 'pipe', 'pipe'],
    });

    let stderr = '';

    child.stderr.on('data', (chunk: Buffer) => {
      stderr += chunk.toString();
    });

    child.on('error', (err) => {
      reject(new Error(`EdgeTTS 命令不可用: ${err.message}\n请安装：pip install edge-tts`));
    });

    child.on('close', (code) => {
      if (code === 0 && fs.existsSync(finalPath)) {
        const stats = fs.statSync(finalPath);
        const elapsed = Date.now() - startTime;
        console.log(`✅ [EdgeTTS] 完成: ${finalPath} (${stats.size} bytes, ${elapsed}ms)`);
        resolve(finalPath);
      } else {
        const errMsg = `EdgeTTS 合成失败 (code=${code}): ${stderr.substring(0, 300)}`;
        console.error(`❌ [EdgeTTS] ${errMsg}`);
        reject(new Error(errMsg));
      }
    });
  }

  /** 健康检查：edge-tts 命令是否可用 */
  async healthCheck(): Promise<boolean> {
    return new Promise((resolve) => {
      const child = spawn('edge-tts', ['--list-voices'], {
        shell: false,
        stdio: 'pipe',
      });

      const timer = setTimeout(() => {
        child.kill();
        resolve(false);
      }, 10000);

      child.on('error', () => {
        clearTimeout(timer);
        // 尝试 python -m
        const pythonChild = spawn('python', ['-m', 'edge_tts', '--list-voices'], {
          stdio: 'pipe',
        });
        pythonChild.on('close', (code) => {
          clearTimeout(timer);
          resolve(code === 0);
        });
        pythonChild.on('error', () => {
          clearTimeout(timer);
          resolve(false);
        });
      });

      child.on('close', (code) => {
        clearTimeout(timer);
        resolve(code === 0);
      });
    });
  }
}