require('dotenv').config();

const path = require('path');

// Database configuration for different environments
const resolveSqliteFilename = (filenameEnv) => {
  const fallback = path.join(__dirname, './data/photo_sharing.db');

  if (!filenameEnv) {
    return fallback;
  }

  const trimmed = String(filenameEnv).trim();
  if (!trimmed) {
    return fallback;
  }

  let resolved;
  if (path.isAbsolute(trimmed)) {
    resolved = trimmed;
  } else if (trimmed.startsWith('./') || trimmed.startsWith('../')) {
    resolved = path.resolve(__dirname, trimmed);
  } else {
    resolved = path.join(__dirname, trimmed);
  }

  const normalized = path.normalize(resolved);
  const baseSuffix = path.relative(path.parse(__dirname).root, path.normalize(__dirname));
  const duplicatePattern = `${path.sep}${baseSuffix}${path.sep}${baseSuffix}`;

  if (normalized.includes(duplicatePattern)) {
    return normalized.replace(duplicatePattern, `${path.sep}${baseSuffix}`);
  }

  return normalized;
};

const sqliteConnection = (filenameEnv) => ({
  filename: resolveSqliteFilename(filenameEnv)
});

const baseSqliteConfig = {
  client: 'sqlite3',
  connection: sqliteConnection(),
  useNullAsDefault: true,
  migrations: {
    directory: './migrations'
  },
  seeds: {
    directory: './seeds'
  }
};

const config = {
  development: {
    client: process.env.DATABASE_CLIENT || 'sqlite3',
    connection: process.env.DATABASE_CLIENT === 'pg' ? {
      host: process.env.DB_HOST || 'localhost',
      port: process.env.DB_PORT || 5432,
      user: process.env.DB_USER || 'postgres',
      password: process.env.DB_PASSWORD || 'postgres',
      database: process.env.DB_NAME || 'photo_sharing'
    } : {
      filename: resolveSqliteFilename(process.env.DATABASE_PATH || './data/photo_sharing.db')
    },
    useNullAsDefault: process.env.DATABASE_CLIENT !== 'pg',
    migrations: {
      directory: './migrations'
    },
    seeds: {
      directory: './seeds'
    }
  },

  test: (() => {
    const client = process.env.DATABASE_CLIENT || 'sqlite3';
    const isPostgres = client === 'pg';

    return {
      ...baseSqliteConfig,
      client,
      useNullAsDefault: !isPostgres,
      connection: isPostgres
        ? {
            host: process.env.DB_HOST || 'localhost',
            port: process.env.DB_PORT || 5432,
            user: process.env.DB_USER || 'postgres',
            password: process.env.DB_PASSWORD || 'postgres',
            database: process.env.DB_NAME || 'photo_sharing_test'
          }
        : sqliteConnection(process.env.TEST_DATABASE_PATH || './data/photo_sharing_test.db')
    };
  })(),

  production: {
    client: process.env.DATABASE_CLIENT || 'pg',
    // Support both Postgres and SQLite in production based on DATABASE_CLIENT
    connection: (process.env.DATABASE_CLIENT || 'pg') === 'pg'
      ? {
          host: process.env.DB_HOST || 'db',
          port: process.env.DB_PORT || 5432,
          user: process.env.DB_USER || 'picpeak',
          password: process.env.DB_PASSWORD,
          database: process.env.DB_NAME || 'picpeak',
          ssl: process.env.DB_SSL === 'true' ? { rejectUnauthorized: false } : false,
          // Connection stability settings
          connectionTimeoutMillis: 30000,
          idleTimeoutMillis: 30000,
          keepAlive: true,
          keepAliveInitialDelayMillis: 0
        }
      : {
          filename: resolveSqliteFilename(process.env.DATABASE_PATH || './data/photo_sharing.db')
        },
    useNullAsDefault: (process.env.DATABASE_CLIENT || 'pg') !== 'pg',
    pool: (process.env.DATABASE_CLIENT || 'pg') === 'pg'
      ? {
          min: 5,
          max: 25,
          acquireTimeoutMillis: 60000,
          createTimeoutMillis: 60000,
          idleTimeoutMillis: 30000,
          reapIntervalMillis: 1000,
          createRetryIntervalMillis: 200,
          propagateCreateError: false
        }
      : undefined,
    migrations: {
      directory: './migrations'
    },
    acquireConnectionTimeout: 60000
  }
};
const env = process.env.NODE_ENV || 'development';

module.exports = config[env] || config.development;