// 性能优化配置文件
module.exports = {
  // 资源预加载策略
  preload: {
    // 关键资源预加载
    critical: ['vue-vendor', 'element-ui', 'main'],
    // 预获取异步资源
    prefetch: true,
    // 字体预加载
    fonts: [
      '/font/iconfont.woff2',
      '/font/youaimoshouruifang.ttf'
    ]
  },

  // 图片优化
  images: {
    // 内联阈值
    inlineLimit: 4 * 1024, // 4KB
    // 压缩配置
    compression: {
      jpeg: { quality: 85, progressive: true },
      png: { quality: [0.65, 0.90], speed: 4 },
      webp: { quality: 85 },
      svg: { plugins: [{ name: 'preset-default' }] }
    },
    // 支持的格式
    formats: ['webp', 'avif', 'jpg', 'png'],
    // 响应式图片
    responsive: {
      sizes: [320, 640, 960, 1280, 1920],
      formats: ['webp', 'jpg']
    }
  },

  // 代码分割策略
  splitChunks: {
    strategy: 'balanced', // 平衡策略
    maxInitialRequests: 6,
    maxAsyncRequests: 8,
    minSize: 100000, // 100KB
    maxSize: 8000000, // 8MB
    // 分包规则
    groups: {
      vue: { priority: 30, test: /vue|vue-router|vuex/ },
      elementUI: { priority: 25, test: /element-ui/ },
      largeLibs: { priority: 23, test: /echarts|artplayer|hls\.js/ },
      utils: { priority: 21, test: /lodash|moment|axios/ },
      ctComponents: { priority: 20, test: /@ct/ },
      vendor: { priority: 10, test: /node_modules/ }
    }
  },

  // 缓存策略
  cache: {
    type: 'filesystem',
    maxAge: 7 * 24 * 60 * 60 * 1000, // 7天
    compression: 'gzip',
    buildDependencies: ['config']
  },

  // 压缩配置
  compression: {
    gzip: {
      threshold: 8192, // 8KB
      minRatio: 0.8,
      algorithm: 'gzip'
    },
    brotli: {
      threshold: 8192,
      minRatio: 0.8,
      level: 11
    }
  },

  // 开发服务器优化
  devServer: {
    writeToDisk: false,
    compress: true,
    hot: true,
    stats: 'errors-warnings'
  },

  // 构建优化
  build: {
    // 并行处理
    parallel: 2,
    // 生产环境优化
    production: {
      dropConsole: true,
      dropDebugger: true,
      minify: true,
      extractCSS: true
    },
    // 开发环境优化
    development: {
      sourcemap: 'eval-cheap-module-source-map',
      cache: true,
      hmr: true
    }
  },

  // 监控和分析
  analyze: {
    // 包大小分析
    bundleAnalyzer: false,
    // 性能预算
    performanceBudget: {
      maxAssetSize: 2000000, // 2MB
      maxEntrypointSize: 2000000, // 2MB
      hints: 'warning'
    }
  }
}