const fs = require("fs");
const path = require("path");
const logger = require("../lib/logger");

// Use a separate database instance for migration to avoid conflicts
const Database = require("../lib/database");

async function migrateJsonToDatabase() {
  const migrationDb = new Database();

  try {
    console.log("🚀 Starting migration from JSON to database...");

    // Initialize migration database
    await migrationDb.init();

    // Check if firm.json exists
    const firmJsonPath = path.join(__dirname, "..", "firm.json");
    if (!fs.existsSync(firmJsonPath)) {
      console.log("❌ firm.json not found. No migration needed.");
      return;
    }

    // Read and parse firm.json
    const firmData = JSON.parse(fs.readFileSync(firmJsonPath, "utf8"));
    console.log("📖 Read firm.json successfully");

    // Flatten the data structure (it's organized by state)
    const allFirms = [];
    for (const [state, firms] of Object.entries(firmData)) {
      if (Array.isArray(firms)) {
        firms.forEach((firm) => {
          // Normalize firm data
          allFirms.push({
            firmName: firm.firmName,
            location: firm.location,
            website: firm.website,
            contactEmail: firm.contactEmail || firm.email,
            state: state,
          });
        });
      }
    }

    console.log(
      `📊 Found ${allFirms.length} firms across ${
        Object.keys(firmData).length
      } states`
    );

    // Filter out firms without email addresses
    const validFirms = allFirms.filter((firm) => firm.contactEmail);
    console.log(`✅ ${validFirms.length} firms have valid email addresses`);

    if (validFirms.length !== allFirms.length) {
      console.log(
        `⚠️  Skipped ${
          allFirms.length - validFirms.length
        } firms without email addresses`
      );
    }

    // Insert firms into database
    const inserted = await migrationDb.insertFirmsBatch(validFirms);
    console.log(`✨ Inserted ${inserted} new firms into database`);

    // Remove duplicates
    const duplicatesRemoved = await migrationDb.removeDuplicateFirms();
    if (duplicatesRemoved > 0) {
      console.log(`🧹 Removed ${duplicatesRemoved} duplicate firms`);
    }

    // Get final counts
    const counts = await migrationDb.getTableCounts();
    console.log("📈 Final database counts:", counts);

    // Create backup of JSON file
    const backupPath = path.join(
      __dirname,
      "..",
      `firm.json.backup.${Date.now()}`
    );
    fs.copyFileSync(firmJsonPath, backupPath);
    console.log(`💾 Created backup: ${path.basename(backupPath)}`);

    console.log("✅ Migration completed successfully!");
  } catch (error) {
    console.error("❌ Migration failed:", error.message);
    logger.error("Migration failed", {
      error: error.message,
      stack: error.stack,
    });
    throw error;
  } finally {
    // Only close if not called from main app
    await migrationDb.close();
  }
}

// Run migration if script is called directly
if (require.main === module) {
  migrateJsonToDatabase()
    .then(() => {
      console.log("Migration script completed");
      process.exit(0);
    })
    .catch((error) => {
      console.error("Migration script failed:", error);
      process.exit(1);
    });
}

module.exports = { migrateJsonToDatabase };