/**
 * 云雾AI API 适配器 · yunwu.ai
 * D136+ · 铸渊 ICE-GL-ZY001 · 2026-06-21
 * 
 * Base URL: https://yunwu.ai/v1
 * 模型: kling-video, kling-omni-video, kling-video-extend, kling-motion-control
 * 兼容 OpenAI 格式
 * 
 * 密钥: 从 video-ai-system/.env 或环境变量 YUNWU_API_KEY 读取
 */
const fs = require('fs');
const path = require('path');
const https = require('https');

const envPath = path.resolve(__dirname, '../.env');
if (fs.existsSync(envPath)) {
  const envContent = fs.readFileSync(envPath, 'utf-8');
  envContent.split('\n').forEach(line => {
    const trimmed = line.trim();
    if (trimmed && !trimmed.startsWith('#')) {
      const [key, ...vals] = trimmed.split('=');
      if (key && vals.length) process.env[key.trim()] = vals.join('=').trim();
    }
  });
}

const API_KEY = process.env.YUNWU_API_KEY || '';
const BASE_URL = 'yunwu.ai';
const BASE_PATH = '/v1';

const JZAO_SHOTS = '/Volumes/JZAO/铸渊-ICE-GL-ZY001/OUT-输出/视频/zai-fu-fei-xiu-xian/ep01';
const LOCAL_SHOTS = path.resolve(__dirname, '../outputs/shots');
const OUT_DIR = fs.existsSync(JZAO_SHOTS) ? JZAO_SHOTS : LOCAL_SHOTS;

function apiRequest(method, path_, body = null) {
  return new Promise((resolve, reject) => {
    const options = {
      hostname: BASE_URL,
      path: path_,
      method,
      headers: {
        'Authorization': `Bearer ${API_KEY}`,
        'Content-Type': 'application/json',
      },
    };
    const req = https.request(options, (res) => {
      let data = '';
      res.on('data', chunk => data += chunk);
      res.on('end', () => {
        try { resolve({ status: res.statusCode, ...JSON.parse(data) }); }
        catch (e) { resolve({ status: res.statusCode, raw: data }); }
      });
    });
    req.on('error', reject);
    req.setTimeout(300000, () => { req.destroy(); reject(new Error('timeout')); });
    if (body) req.write(JSON.stringify(body));
    req.end();
  });
}

function downloadFile(url, dest) {
  return new Promise((resolve, reject) => {
    const file = fs.createWriteStream(dest);
    const proto = url.startsWith('https') ? https : require('http');
    proto.get(url, (res) => {
      if (res.statusCode >= 300 && res.statusCode < 400) {
        return downloadFile(res.headers.location, dest).then(resolve).catch(reject);
      }
      res.pipe(file);
      file.on('finish', () => { file.close(); resolve(dest); });
    }).on('error', reject);
  });
}

/**
 * 云雾AI视频生成 - 两层策略:
 * 1. chat/completions 提交 → 检查响应中是否有视频数据
 * 2. 如果chat返回空 → 尝试 video/generations 端点
 */
async function generateVideo({ prompt, duration = 5, outputPath, model = 'kling-video' }) {
  if (!API_KEY) {
    throw new Error('YUNWU_API_KEY 未设置。请写入 video-ai-system/.env 或环境变量。');
  }

  console.log('[yunwu.ai] 策略1: chat/completions 提交...');

  // ═══ 策略1: chat/completions ═══
  try {
    const chatRes = await apiRequest('POST', `${BASE_PATH}/chat/completions`, {
      model,
      messages: [{ role: 'user', content: prompt }],
      max_tokens: 4096,
    });

    // 检查响应中是否有视频URL或错误信息
    if (chatRes.error) {
      console.log(`[yunwu.ai] chat返回错误: ${JSON.stringify(chatRes.error).substring(0,200)}`);
    } else if (chatRes.choices && chatRes.choices[0]?.message?.content) {
      const content = chatRes.choices[0].message.content;
      // 检查是否包含视频URL
      const urlMatch = content.match(/https?:\/\/[^\s]+\.mp4[^\s]*/);
      if (urlMatch) {
        const videoUrl = urlMatch[0];
        const out = outputPath || path.join(OUT_DIR, `yunwu-${Date.now()}.mp4`);
        fs.mkdirSync(path.dirname(out), { recursive: true });
        console.log(`[yunwu.ai] 下载视频...`);
        await downloadFile(videoUrl, out);
        console.log(`[yunwu.ai] ✅ ${path.basename(out)}`);
        return { videoPath: out, taskId: chatRes.id };
      }
    } else if (chatRes.choices === null && chatRes.usage?.prompt_tokens > 0) {
      console.log(`[yunwu.ai] chat接收了提示词但未生成视频(上游Kling返回空)`);
    }
  } catch (e) {
    console.log(`[yunwu.ai] chat异常: ${e.message}`);
  }

  // ═══ 策略2: video/generations 端点 ═══
  console.log('[yunwu.ai] 策略2: video/generations 端点...');
  
  try {
    const videoRes = await apiRequest('POST', `${BASE_PATH}/video/generations`, {
      model,
      prompt,
      duration,
      aspect_ratio: '16:9',
    });

    if (videoRes.code === 500 || videoRes.error) {
      throw new Error(videoRes.message || videoRes.error?.message || 'video endpoint failed');
    }

    if (videoRes.data?.task_id) {
      const taskId = videoRes.data.task_id;
      console.log(`[yunwu.ai] 任务: ${taskId}`);
      
      for (let i = 0; i < 180; i++) {
        await new Promise(r => setTimeout(r, 2000));
        const status = await apiRequest('GET', `${BASE_PATH}/video/generations/${taskId}`);
        if (status.data?.task_status === 'succeed' || status.data?.task_status === 'completed') {
          const videoUrl = status.data.video_url || status.data.task_result?.videos?.[0]?.url;
          if (videoUrl) {
            const out = outputPath || path.join(OUT_DIR, `yunwu-${taskId}.mp4`);
            fs.mkdirSync(path.dirname(out), { recursive: true });
            await downloadFile(videoUrl, out);
            console.log(`[yunwu.ai] ✅ ${path.basename(out)}`);
            return { videoPath: out, taskId };
          }
          throw new Error('任务完成但无视频URL');
        }
        if (status.data?.task_status === 'failed') {
          throw new Error(`任务失败: ${JSON.stringify(status.data)}`);
        }
      }
      throw new Error('轮询超时');
    }
  } catch (e) {
    console.log(`[yunwu.ai] video端点异常: ${e.message}`);
  }

  throw new Error('yunwu.ai: 所有策略均失败。可能需要检查模型通道配置。');
}

module.exports = { generateVideo };