#!/usr/bin/env node

/**
 * Theme Class Migration Script
 * 
 * This script helps identify and replace hardcoded color classes with theme-aware classes.
 */

const fs = require('fs');
const path = require('path');

// Define replacement mappings
const CLASS_REPLACEMENTS = {
  // Background colors
  'bg-gray-50 dark:bg-gray-900': 'theme-bg-page',
  'bg-gray-50 dark:bg-gray-800': 'theme-bg-secondary',
  'bg-white dark:bg-gray-900': 'theme-bg',
  'bg-white dark:bg-gray-800': 'theme-bg',
  'bg-gray-100 dark:bg-gray-800': 'theme-bg-secondary',
  'bg-gray-200 dark:bg-gray-700': 'theme-bg-secondary',
  
  // Text colors
  'text-gray-900 dark:text-gray-100': 'theme-text',
  'text-gray-900 dark:text-white': 'theme-text',
  'text-gray-700 dark:text-gray-200': 'theme-text',
  'text-gray-600 dark:text-gray-400': 'theme-text-secondary',
  'text-gray-500 dark:text-gray-400': 'theme-text-muted',
  'text-gray-500': 'theme-text-muted',
  
  // Border colors
  'border-gray-200 dark:border-gray-700': 'theme-border',
  'border-gray-300 dark:border-gray-600': 'theme-border',
  'border-stone-200 dark:border-gray-700': 'theme-border',
  
  // Common patterns
  'bg-gray-50 dark:bg-gray-800 rounded-lg p-6': 'theme-card',
  'text-xl font-semibold text-gray-900 dark:text-gray-100 mb-4': 'theme-text-heading',
  'text-gray-600 dark:text-gray-400 mb-4': 'theme-text-body',
  'text-sm text-gray-500': 'theme-text-caption',
};

// Individual class mappings (for cases where full context isn't available)
const INDIVIDUAL_REPLACEMENTS = {
  'text-gray-900': 'theme-text',
  'text-gray-700': 'theme-text', 
  'text-gray-600': 'theme-text-secondary',
  'text-gray-500': 'theme-text-muted',
  'text-gray-400': 'theme-text-muted',
  'bg-gray-50': 'theme-bg-secondary',
  'bg-gray-100': 'theme-bg-secondary',
  'bg-gray-800': 'theme-bg-secondary',
  'bg-gray-900': 'theme-bg-page',
  'border-gray-200': 'theme-border',
  'border-gray-300': 'theme-border',
};

function findRustFiles(dir) {
  const files = [];
  
  function walk(currentPath) {
    const items = fs.readdirSync(currentPath);
    
    for (const item of items) {
      const fullPath = path.join(currentPath, item);
      const stat = fs.statSync(fullPath);
      
      if (stat.isDirectory() && !item.startsWith('.') && item !== 'target') {
        walk(fullPath);
      } else if (item.endsWith('.rs')) {
        files.push(fullPath);
      }
    }
  }
  
  walk(dir);
  return files;
}

function analyzeFile(filePath) {
  const content = fs.readFileSync(filePath, 'utf8');
  const issues = [];
  
  // Find hardcoded gray/stone classes
  const grayClassRegex = /(text|bg|border)-(gray|stone)-\d+/g;
  const darkModeRegex = /(text|bg|border)-(gray|stone)-\d+\s+dark:(text|bg|border)-(gray|stone)-\d+/g;
  
  let match;
  while ((match = grayClassRegex.exec(content)) !== null) {
    issues.push({
      type: 'hardcoded-class',
      class: match[0],
      line: content.substring(0, match.index).split('\n').length,
      suggestion: INDIVIDUAL_REPLACEMENTS[match[0]] || 'theme-*'
    });
  }
  
  // Check for complex patterns
  for (const [pattern, replacement] of Object.entries(CLASS_REPLACEMENTS)) {
    if (content.includes(pattern)) {
      issues.push({
        type: 'complex-pattern',
        pattern,
        replacement,
        line: content.substring(0, content.indexOf(pattern)).split('\n').length
      });
    }
  }
  
  return issues;
}

function generateReport(clientDir) {
  console.log('🔍 Analyzing theme class usage...\n');
  
  const files = findRustFiles(clientDir);
  let totalIssues = 0;
  
  for (const file of files) {
    const issues = analyzeFile(file);
    
    if (issues.length > 0) {
      console.log(`📄 ${path.relative(process.cwd(), file)}:`);
      
      for (const issue of issues) {
        totalIssues++;
        
        if (issue.type === 'hardcoded-class') {
          console.log(`  Line ${issue.line}: ${issue.class} → ${issue.suggestion}`);
        } else {
          console.log(`  Line ${issue.line}: Complex pattern found`);
          console.log(`    Replace: ${issue.pattern}`);
          console.log(`    With: ${issue.replacement}`);
        }
      }
      console.log('');
    }
  }
  
  console.log(`📊 Summary: Found ${totalIssues} hardcoded classes to migrate`);
  
  if (totalIssues > 0) {
    console.log('\n💡 Migration Strategy:');
    console.log('1. Use theme-aware classes: theme-text, theme-bg, theme-border');
    console.log('2. For complex patterns, use composite classes: theme-card, theme-text-heading');
    console.log('3. Test with different themes: npm run theme:build purple');
    console.log('4. Verify colors change when switching themes');
  }
}

function migrateSingleFile(filePath, dryRun = true) {
  console.log(`🔧 ${dryRun ? 'Analyzing' : 'Migrating'}: ${filePath}`);
  
  let content = fs.readFileSync(filePath, 'utf8');
  let changes = 0;
  
  // Apply complex pattern replacements first
  for (const [pattern, replacement] of Object.entries(CLASS_REPLACEMENTS)) {
    if (content.includes(pattern)) {
      console.log(`  Replacing: ${pattern} → ${replacement}`);
      content = content.replace(new RegExp(pattern.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'), 'g'), replacement);
      changes++;
    }
  }
  
  if (!dryRun && changes > 0) {
    fs.writeFileSync(filePath, content);
    console.log(`✅ Applied ${changes} changes to ${filePath}`);
  } else if (changes > 0) {
    console.log(`📋 Would apply ${changes} changes (use --apply to execute)`);
  } else {
    console.log(`✨ No changes needed`);
  }
  
  return changes;
}

// CLI handling
if (require.main === module) {
  const args = process.argv.slice(2);
  const command = args[0];
  
  if (command === 'analyze' || !command) {
    const clientDir = path.join(__dirname, '..', 'crates', 'client');
    generateReport(clientDir);
  } else if (command === 'migrate') {
    const filePath = args[1];
    const dryRun = !args.includes('--apply');
    
    if (!filePath) {
      console.error('Usage: migrate <file-path> [--apply]');
      process.exit(1);
    }
    
    migrateSingleFile(filePath, dryRun);
  } else {
    console.log('Usage:');
    console.log('  node migrate-theme-classes.js analyze');
    console.log('  node migrate-theme-classes.js migrate <file> [--apply]');
  }
}

module.exports = { generateReport, migrateSingleFile, CLASS_REPLACEMENTS };