#!/usr/bin/env node
/**
 * Migration Script: Standardize Blog Titles
 * 
 * This script standardizes all Daily Digest titles to the format:
 * "## Daily Digest - Monday, February 24, 2026"
 * 
 * Run: node migrate-titles.js [--dry-run]
 */

require('dotenv').config({ path: require('path').join(__dirname, '..', '.env.local') });
const { createClient } = require('@supabase/supabase-js');

const SUPABASE_URL = process.env.NEXT_PUBLIC_SUPABASE_URL || 'https://qnatchrjlpehiijwtreh.supabase.co';
const SUPABASE_SERVICE_KEY = process.env.SUPABASE_SERVICE_ROLE_KEY || process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY;

if (!SUPABASE_SERVICE_KEY) {
  console.error('Error: SUPABASE_SERVICE_ROLE_KEY or NEXT_PUBLIC_SUPABASE_ANON_KEY environment variable required');
  process.exit(1);
}

const supabase = createClient(SUPABASE_URL, SUPABASE_SERVICE_KEY);

/**
 * Get day name from date string (YYYY-MM-DD)
 */
function getDayName(dateStr) {
  const days = ['Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'];
  const date = new Date(dateStr + 'T12:00:00'); // Use noon to avoid timezone issues
  return days[date.getDay()];
}

/**
 * Format date for title (e.g., "February 24, 2026")
 */
function formatDateForTitle(dateStr) {
  const months = [
    'January', 'February', 'March', 'April', 'May', 'June',
    'July', 'August', 'September', 'October', 'November', 'December'
  ];
  const [year, month, day] = dateStr.split('-');
  const monthName = months[parseInt(month, 10) - 1];
  return `${monthName} ${parseInt(day, 10)}, ${year}`;
}

/**
 * Generate standardized title
 */
function generateStandardTitle(dateStr) {
  const dayName = getDayName(dateStr);
  const datePart = formatDateForTitle(dateStr);
  return `## Daily Digest - ${dayName}, ${datePart}`;
}

/**
 * Extract current title from content
 */
function extractCurrentTitle(content) {
  const lines = content.split('\n');
  const titleLine = lines.find(l => l.startsWith('# ') || l.startsWith('## '));
  return titleLine || null;
}

/**
 * Replace title in content
 */
function replaceTitle(content, newTitle) {
  const lines = content.split('\n');
  const titleIndex = lines.findIndex(l => l.startsWith('# ') || l.startsWith('## '));
  
  if (titleIndex === -1) {
    // No title found, prepend new title
    return newTitle + '\n\n' + content;
  }
  
  // Replace existing title line
  lines[titleIndex] = newTitle;
  return lines.join('\n');
}

/**
 * Process all messages and update titles
 */
async function migrateTitles(dryRun = false) {
  console.log('🔄 Fetching all blog messages...\n');
  
  const { data: messages, error } = await supabase
    .from('blog_messages')
    .select('id, date, content')
    .order('date', { ascending: false });
  
  if (error) {
    console.error('Error fetching messages:', error);
    process.exit(1);
  }
  
  console.log(`Found ${messages.length} messages\n`);
  
  const updates = [];
  const skipped = [];
  
  for (const message of messages) {
    const currentTitle = extractCurrentTitle(message.content);
    const newTitle = generateStandardTitle(message.date);
    
    // Check if update is needed
    if (currentTitle === newTitle) {
      skipped.push({
        id: message.id,
        date: message.date,
        title: currentTitle,
        reason: 'Already in standard format'
      });
      continue;
    }
    
    updates.push({
      id: message.id,
      date: message.date,
      oldTitle: currentTitle,
      newTitle: newTitle
    });
    
    if (!dryRun) {
      const newContent = replaceTitle(message.content, newTitle);
      
      const { error: updateError } = await supabase
        .from('blog_messages')
        .update({ content: newContent })
        .eq('id', message.id);
      
      if (updateError) {
        console.error(`❌ Error updating message ${message.id}:`, updateError);
      } else {
        console.log(`✅ Updated: ${message.date}`);
        console.log(`   Old: ${currentTitle}`);
        console.log(`   New: ${newTitle}\n`);
      }
    }
  }
  
  // Summary
  console.log('\n' + '='.repeat(60));
  console.log('MIGRATION SUMMARY');
  console.log('='.repeat(60));
  console.log(`Total messages: ${messages.length}`);
  console.log(`Updates needed: ${updates.length}`);
  console.log(`Already correct: ${skipped.length}`);
  
  if (dryRun) {
    console.log('\n📋 DRY RUN - No changes made\n');
    if (updates.length > 0) {
      console.log('Proposed changes:');
      updates.forEach(u => {
        console.log(`\n${u.date}:`);
        console.log(`  From: ${u.oldTitle}`);
        console.log(`  To:   ${u.newTitle}`);
      });
    }
  } else {
    console.log(`\n✅ Migration complete!`);
  }
  
  return { updates, skipped };
}

// Main execution
const dryRun = process.argv.includes('--dry-run');

if (dryRun) {
  console.log('🔍 DRY RUN MODE - No changes will be made\n');
}

migrateTitles(dryRun)
  .then(() => process.exit(0))
  .catch(err => {
    console.error('Migration failed:', err);
    process.exit(1);
  });