#!/usr/bin/env node

/**
 * Bundle 分析脚本
 * 用于分析 Naive UI 组件的打包情况和优化建议
 */

import { execSync } from 'child_process'
import { readFileSync, writeFileSync } from 'fs'
import { resolve } from 'path'

const DIST_PATH = resolve(process.cwd(), 'dist')
const ANALYSIS_OUTPUT = resolve(process.cwd(), 'bundle-analysis.json')

/**
 * 分析打包结果
 */
function analyzeBundleSize() {
  console.log('🔍 开始分析打包结果...')
  
  try {
    // 构建生产版本
    console.log('📦 构建生产版本...')
    execSync('npm run build', { stdio: 'inherit' })
    
    // 获取文件大小信息
    const result = execSync(`find ${DIST_PATH} -name "*.js" -o -name "*.css" | xargs ls -la`, 
      { encoding: 'utf-8' })
    
    const files = result.split('\n')
      .filter(line => line.trim())
      .map(line => {
        const parts = line.split(/\s+/)
        const size = parseInt(parts[4])
        const name = parts[parts.length - 1].replace(DIST_PATH + '/', '')
        return { name, size, sizeKB: Math.round(size / 1024 * 100) / 100 }
      })
      .filter(file => file.size > 0)
      .sort((a, b) => b.size - a.size)
    
    // 分析 Naive UI 相关文件
    const naiveUIFiles = files.filter(file => 
      file.name.includes('naive-ui') || 
      file.name.includes('naive')
    )
    
    const totalSize = files.reduce((sum, file) => sum + file.size, 0)
    const naiveUISize = naiveUIFiles.reduce((sum, file) => sum + file.size, 0)
    
    const analysis = {
      timestamp: new Date().toISOString(),
      totalFiles: files.length,
      totalSizeKB: Math.round(totalSize / 1024 * 100) / 100,
      naiveUIFiles: naiveUIFiles.length,
      naiveUISizeKB: Math.round(naiveUISize / 1024 * 100) / 100,
      naiveUIPercentage: Math.round(naiveUISize / totalSize * 100 * 100) / 100,
      files: files.slice(0, 20), // 只保留前20个最大的文件
      naiveUIFiles: naiveUIFiles,
      recommendations: generateRecommendations(files, naiveUIFiles, totalSize)
    }
    
    // 保存分析结果
    writeFileSync(ANALYSIS_OUTPUT, JSON.stringify(analysis, null, 2))
    
    // 输出分析报告
    printAnalysisReport(analysis)
    
  } catch (error) {
    console.error('❌ 分析失败:', error.message)
    process.exit(1)
  }
}

/**
 * 生成优化建议
 */
function generateRecommendations(allFiles, naiveUIFiles, totalSize) {
  const recommendations = []
  
  // 检查是否有过大的单个文件
  const largeFiles = allFiles.filter(file => file.size > 500 * 1024) // 大于500KB
  if (largeFiles.length > 0) {
    recommendations.push({
      type: 'warning',
      title: '发现大文件',
      description: `有 ${largeFiles.length} 个文件超过 500KB，建议进一步拆分`,
      files: largeFiles.map(f => f.name)
    })
  }
  
  // 检查 Naive UI 占比
  const naiveUIPercentage = naiveUIFiles.reduce((sum, file) => sum + file.size, 0) / totalSize * 100
  if (naiveUIPercentage > 30) {
    recommendations.push({
      type: 'info',
      title: 'Naive UI 占比较高',
      description: `Naive UI 组件占总包体积的 ${Math.round(naiveUIPercentage)}%，可以考虑更精细的按需引入`,
      suggestion: '使用 tree-shaking 或更细粒度的组件拆分'
    })
  }
  
  // 检查是否有重复的组件
  const duplicatePattern = /naive-ui.*\.(js|css)$/
  const duplicates = allFiles.filter(file => duplicatePattern.test(file.name))
  if (duplicates.length > 5) {
    recommendations.push({
      type: 'warning',
      title: '可能存在组件重复',
      description: '发现多个 Naive UI 相关文件，可能存在重复打包',
      suggestion: '检查 webpack 配置中的 splitChunks 设置'
    })
  }
  
  // 检查 CSS 文件大小
  const cssFiles = allFiles.filter(file => file.name.endsWith('.css'))
  const largeCSSFiles = cssFiles.filter(file => file.size > 100 * 1024) // 大于100KB
  if (largeCSSFiles.length > 0) {
    recommendations.push({
      type: 'info',
      title: 'CSS 文件较大',
      description: '发现较大的 CSS 文件，可以考虑按需加载样式',
      files: largeCSSFiles.map(f => f.name)
    })
  }
  
  return recommendations
}

/**
 * 打印分析报告
 */
function printAnalysisReport(analysis) {
  console.log('\n📊 Bundle 分析报告')
  console.log('='.repeat(50))
  console.log(`📁 总文件数: ${analysis.totalFiles}`)
  console.log(`📦 总大小: ${analysis.totalSizeKB} KB`)
  console.log(`🎨 Naive UI 文件数: ${analysis.naiveUIFiles.length}`)
  console.log(`🎨 Naive UI 大小: ${analysis.naiveUISizeKB} KB (${analysis.naiveUIPercentage}%)`)
  
  console.log('\n📋 最大的文件:')
  analysis.files.slice(0, 10).forEach((file, index) => {
    console.log(`${index + 1}. ${file.name}: ${file.sizeKB} KB`)
  })
  
  if (analysis.naiveUIFiles.length > 0) {
    console.log('\n🎨 Naive UI 相关文件:')
    analysis.naiveUIFiles.forEach((file, index) => {
      console.log(`${index + 1}. ${file.name}: ${file.sizeKB} KB`)
    })
  }
  
  if (analysis.recommendations.length > 0) {
    console.log('\n💡 优化建议:')
    analysis.recommendations.forEach((rec, index) => {
      const icon = rec.type === 'warning' ? '⚠️' : 'ℹ️'
      console.log(`${icon} ${index + 1}. ${rec.title}`)
      console.log(`   ${rec.description}`)
      if (rec.suggestion) {
        console.log(`   建议: ${rec.suggestion}`)
      }
      if (rec.files) {
        console.log(`   文件: ${rec.files.join(', ')}`)
      }
      console.log('')
    })
  }
  
  console.log(`\n💾 详细分析结果已保存到: ${ANALYSIS_OUTPUT}`)
}

// 运行分析
if (import.meta.url === `file://${process.argv[1]}`) {
  analyzeBundleSize()
}

export { analyzeBundleSize }