#!/usr/bin/env node

/**
 * Update Cache Version - Unified Cache Busting
 *
 * CRITICAL: Run this script EVERY TIME JavaScript files are modified!
 *
 * Updates:
 * 1. All HTML files with ?v= cache-busting parameters
 * 2. public/service-worker.js CACHE_VERSION constant
 * 3. public/version.json with new version and changelog
 *
 * Format: v={package.version}.{timestamp}
 * Example: v=0.1.0.1760201234
 *
 * This ensures:
 * - Browser cache is invalidated
 * - Service worker forces refresh
 * - Version tracking is updated
 */

const fs = require('fs');
const path = require('path');
const packageJson = require('../package.json');

// Parse semantic version from package.json
const [major, minor, patch] = packageJson.version.split('.').map(Number);

// Generate cache version: package version + timestamp
const timestamp = Date.now();
const CACHE_VERSION = `${packageJson.version}.${timestamp}`;

// Bump patch version for version.json
const NEW_SEMVER = `${major}.${minor}.${patch + 1}`;
const VERSION_FILE = path.join(__dirname, '../public/version.json');
const SERVICE_WORKER_FILE = path.join(__dirname, '../public/service-worker.js');

// HTML files to update (relative to project root)
const HTML_FILES = [
  'public/index.html',
  'public/docs.html',
  'public/faq.html',
  'public/researcher.html',
  'public/implementer.html',
  'public/leader.html',
  'public/about.html',
  'public/privacy.html',
  'public/blog.html',
  'public/blog-post.html',
  'public/docs-viewer.html',
  'public/api-reference.html',
  'public/media-inquiry.html',
  'public/case-submission.html',
  'public/koha.html',
  'public/check-version.html',
  'public/village-ai.html',
  'public/architecture.html',
  'public/village-case-study.html',
  'public/architectural-alignment.html',
  'public/architectural-alignment-community.html',
  'public/architectural-alignment-policymakers.html',
  'public/korero-counter-arguments.html',
  'public/admin/blog-curation.html',
  'public/admin/dashboard.html'
];

/**
 * Update cache version in a file
 * Replaces all instances of ?v=X with ?v={CACHE_VERSION}
 */
function updateCacheVersion(filePath) {
  try {
    const fullPath = path.join(__dirname, '..', filePath);

    if (!fs.existsSync(fullPath)) {
      console.warn(`⚠️  File not found: ${filePath}`);
      return false;
    }

    let content = fs.readFileSync(fullPath, 'utf8');
    const originalContent = content;

    // Pattern: ?v=ANYTHING → ?v={CACHE_VERSION}
    // Matches: ?v=1.0.4, ?v=1759833751, ?v=1.0.5.1760123456
    content = content.replace(/\?v=[0-9a-zA-Z._-]+/g, `?v=${CACHE_VERSION}`);

    // Also catch bare CSS/JS references that are missing ?v= entirely
    // Adds ?v= to .css and .js hrefs/srcs that don't have one
    content = content.replace(/(href|src)="([^"]+\.(?:css|js))(?!.*\?v=)"/g, `$1="$2?v=${CACHE_VERSION}"`);

    // Only write if changed
    if (content !== originalContent) {
      fs.writeFileSync(fullPath, content, 'utf8');

      // Count replacements
      const matches = originalContent.match(/\?v=[0-9a-zA-Z._-]+/g) || [];
      console.log(`✅ ${filePath}: Updated ${matches.length} cache version(s)`);
      return true;
    } else {
      console.log(`ℹ️  ${filePath}: No changes needed`);
      return false;
    }

  } catch (error) {
    console.error(`❌ Error updating ${filePath}:`, error.message);
    return false;
  }
}

/**
 * Update service worker CACHE_VERSION
 */
function updateServiceWorker() {
  try {
    let content = fs.readFileSync(SERVICE_WORKER_FILE, 'utf8');
    const original = content;

    // Update CACHE_VERSION constant
    content = content.replace(
      /const CACHE_VERSION = '[^']+';/,
      `const CACHE_VERSION = '${NEW_SEMVER}';`
    );

    if (content !== original) {
      fs.writeFileSync(SERVICE_WORKER_FILE, content);
      console.log(`✅ service-worker.js: Updated CACHE_VERSION to ${NEW_SEMVER}`);
      return true;
    }
    return false;
  } catch (error) {
    console.error(`❌ Error updating service-worker.js:`, error.message);
    return false;
  }
}

/**
 * Update version.json
 */
function updateVersionJson() {
  try {
    const versionData = JSON.parse(fs.readFileSync(VERSION_FILE, 'utf8'));

    versionData.version = NEW_SEMVER;
    versionData.buildDate = new Date().toISOString();
    versionData.forceUpdate = false;

    // Preserve existing changelog
    if (!versionData.changelog) {
      versionData.changelog = ['Cache version update - JavaScript files modified'];
    }

    fs.writeFileSync(VERSION_FILE, JSON.stringify(versionData, null, 2) + '\n');
    console.log(`✅ version.json: Updated to ${NEW_SEMVER}`);
    return true;
  } catch (error) {
    console.error(`❌ Error updating version.json:`, error.message);
    return false;
  }
}

/**
 * Main execution
 */
function main() {
  console.log('');
  console.log('═'.repeat(70));
  console.log('  Tractatus - Cache Version Update (CRITICAL FOR .JS CHANGES)');
  console.log('═'.repeat(70));
  console.log('');
  console.log(`📦 Package version: ${packageJson.version}`);
  console.log(`🔄 New semantic version: ${NEW_SEMVER}`);
  console.log(`🔄 New cache-bust version: ${CACHE_VERSION}`);
  console.log('');

  // Step 1: Update service worker
  console.log('Step 1: Updating service worker...');
  updateServiceWorker();
  console.log('');

  // Step 2: Update version.json
  console.log('Step 2: Updating version.json...');
  updateVersionJson();
  console.log('');

  // Step 3: Update HTML cache parameters
  console.log('Step 3: Updating HTML cache parameters...');
  let updatedCount = 0;
  let totalFiles = 0;

  HTML_FILES.forEach(file => {
    totalFiles++;
    if (updateCacheVersion(file)) {
      updatedCount++;
    }
  });

  console.log('');
  console.log('═'.repeat(70));
  console.log(`  Summary: ${updatedCount}/${totalFiles} HTML files updated`);
  console.log('═'.repeat(70));
  console.log('');

  console.log('✅ Cache version update complete!');
  console.log('');
  console.log('📝 Files modified:');
  console.log('   - public/service-worker.js (CACHE_VERSION)');
  console.log('   - public/version.json (version + buildDate)');
  console.log(`   - ${updatedCount} HTML files (?v= parameters)`);
  console.log('');
  console.log('⚠️  NEXT STEPS:');
  console.log('   1. Review changes: git diff');
  console.log('   2. Commit: git add -A && git commit -m "chore: bump cache version"');
  console.log('   3. Deploy to production');
  console.log('');
}

// Run if called directly
if (require.main === module) {
  main();
}

module.exports = { updateCacheVersion, CACHE_VERSION };