const chalk = require('chalk');
const mongoose = require('mongoose');

const DB = require('./mysql');
const sequelize = require('./config/sequelize');
const associate = require('./relationships');
const DateUtilities = require('../utils/dateUtilities');



// Connect to the MongoDB database and log a message to the console
const connectMongoDb = async () => {
    try {
        if (process.env.APP_ENV === 'production') {
            await mongoose.connect(process.env.MONGODB_URI);
            console.log(`${DateUtilities.getDateTimeISOString()}`, chalk.green('MongoDB connection has been established successfully 🟢'));
        } else {
            mongoose.set('strictQuery', true);
            await mongoose.connect(process.env.MONGODB_URI);
            console.log(`${DateUtilities.getDateTimeISOString()}`, chalk.green('MongoDB connection has been established successfully 🟢'));
            mongoose.set('debug', process.env.DEBUG);
            console.log(`${DateUtilities.getDateTimeISOString()}`, chalk.red('debug :'), chalk.yellow(process.env.DEBUG));
        }
    } catch (error) {
        console.log(`${DateUtilities.getDateTimeISOString()}`, chalk.red('Unable to connect to the MongoDB database 🔴'));
        console.error('MongoDB connection error:', error);
        // Exit the process if the connection is not successful
        process.exit(1);
    }
};

// Connect to the MySQL database and log a message to the console
const connectMysqlDb = async () => {
    try {
        await sequelize.authenticate();
        console.log(`${DateUtilities.getDateTimeISOString()}`, chalk.green('MySQL connection has been established successfully 🟢'));

        // Check that required tables exist instead of synchronizing (no auto-create)
        const queryInterface = sequelize.getQueryInterface();
        let existingTables = [];
        try {
            existingTables = await queryInterface.showAllTables();
        } catch (err) {
            console.log(`${DateUtilities.getDateTimeISOString()}`, chalk.red('Unable to list tables from MySQL 🔴'));
            console.error(err);
            // Exit immediately if unable to list tables
            process.exit(1);
        }

        // Build expected table list from models exported in DB
        const expectedTables = [];
        Object.keys(DB).forEach((key) => {
            const model = DB[key];
            if (model && typeof model.getTableName === 'function') {
                try {
                    const t = model.getTableName();
                    const tableName = typeof t === 'string' ? t : t.tableName;
                    if (tableName) expectedTables.push(tableName);
                // eslint-disable-next-line no-unused-vars
                } catch (err) {
                    // ignore
                }
            }
        });

        // Normalize table names to strings for comparison
        const existingNormalized = existingTables.map(t => (typeof t === 'string' ? t : t.tableName)).map(t => t.toString());

        const missing = expectedTables.filter(t => !existingNormalized.includes(t) && !existingNormalized.includes(t.toLowerCase()));

        if (missing.length > 0) {
            console.log(`${DateUtilities.getDateTimeISOString()}`, chalk.red('Database schema validation failed - missing tables:'), chalk.yellow(missing.join(', ')));
            console.log(`${DateUtilities.getDateTimeISOString()}`, chalk.red('Run migrations to create the schema: npx sequelize-cli db:migrate'));
            // Exit immediately if schema is incomplete
            process.exit(1);
        }

        // If all expected tables are present, create associations
        associate();
        console.log(`${DateUtilities.getDateTimeISOString()}`, chalk.green('Database schema validated successfully 🟢'));

    } catch (error) {
        console.log(`${DateUtilities.getDateTimeISOString()}`, chalk.red('Unable to connect to the MySQL database 🔴'));
        console.error('MySQL connection error:', error);
        // Exit the process if the connection is not successful
        process.exit(1);
    }

};

// Connect to all database and log a message to the console
const connectAllDb = async () => {
    try {
        await connectMongoDb();
        await connectMysqlDb();
    } catch (error) {
        console.error('Failed to connect to databases:', error);
        process.exit(1);
    }
};


module.exports.connectAllDb = connectAllDb;
module.exports.connectMongoDb = connectMongoDb;
module.exports.connectMysqlDb = connectMysqlDb;
module.exports.default = connectAllDb;