import fs from 'fs';
import process from 'process';
import { knex } from 'knex';
import SqlMgrv2 from '../../src/db/sql-mgr/v2/SqlMgrv2';
import type { Knex } from 'knex';
import type { DbConfig } from '../../src/interface/config';
import NcConfigFactory from '../../src/utils/NcConfigFactory'

export default class TestDbMngr {
  public static readonly dbName = 'test_meta';
  public static readonly sakilaDbName = 'test_sakila';
  public static metaKnex: Knex;
  public static sakilaKnex: Knex;

  public static defaultConnection = {
    user: 'root',
    password: 'password',
    host: 'localhost',
    port: 3306,
    client: 'mysql2',
  };

  public static pgConnection = {
    user: 'postgres',
    password: 'password',
    host: 'localhost',
    port: 5432,
    client: 'pg',
  };

  public static connection: {
    user: string;
    password: string;
    host: string;
    port: number;
    client: string;
  } = TestDbMngr.defaultConnection;

  public static dbConfig: DbConfig;

  static populateConnectionConfig() {
    const { user, password, host, port, client } = TestDbMngr.defaultConnection;
    TestDbMngr.connection = {
      user: process.env['DB_USER'] || user,
      password: process.env['DB_PASSWORD'] || password,
      host: process.env['DB_HOST'] || host,
      port: Number(process.env['DB_PORT']) || port,
      client: process.env['DB_CLIENT'] || client,
    };

    console.log(TestDbMngr.connection);
  }

  static async testConnection(config: DbConfig) {
    try {
      console.log('Testing connection', TestDbMngr.connection);
      return await SqlMgrv2.testConnection(config);
    } catch (e) {
      console.log(e);
      return { code: -1, message: 'Connection invalid' };
    }
  }

  static async init() {
    TestDbMngr.populateConnectionConfig();

    // common for both pg and mysql
    if (await TestDbMngr.isDbConfigured()) {
      await TestDbMngr.connectDb();
    } else {
      console.log('Mysql is not configured. Switching to sqlite');
      await TestDbMngr.switchToSqlite();
    }
  }

  private static async isDbConfigured() {
    const { user, password, host, port, client } = TestDbMngr.connection;
    const config = NcConfigFactory.urlToDbConfig(
      `${client}://${user}:${password}@${host}:${port}`,
    );
    config.connection = {
      user,
      password,
      host,
      port,
    };
    const result = await TestDbMngr.testConnection(config);
    return result.code !== -1;
  }
  static async connectDb() {
    const { user, password, host, port, client } = TestDbMngr.connection;
    if (!process.env[`DATABASE_URL`]) {
      process.env[
        `DATABASE_URL`
      ] = `${client}://${user}:${password}@${host}:${port}/${TestDbMngr.dbName}`;
    }

    TestDbMngr.dbConfig = NcConfigFactory.urlToDbConfig(
      NcConfigFactory.extractXcUrlFromJdbc(process.env[`DATABASE_URL`]),
    );
    this.dbConfig.meta = {
      tn: 'nc_evolutions',
      dbAlias: 'db',
      api: {
        type: 'rest',
        prefix: '',
        graphqlDepthLimit: 10,
      },
      inflection: {
        tn: 'camelize',
        cn: 'camelize',
      },
    };

    await TestDbMngr.setupMeta();
    await TestDbMngr.setupSakila();
  }

  static async setupMeta() {
    if (TestDbMngr.metaKnex) {
      await TestDbMngr.metaKnex.destroy();
    }

    if (TestDbMngr.isSqlite()) {
      await TestDbMngr.resetMetaSqlite();
      TestDbMngr.metaKnex = knex(TestDbMngr.getMetaDbConfig());
      return;
    }

    TestDbMngr.metaKnex = knex(TestDbMngr.getDbConfigWithNoDb());
    await TestDbMngr.resetDatabase(TestDbMngr.metaKnex, TestDbMngr.dbName);
    await TestDbMngr.metaKnex.destroy();

    TestDbMngr.metaKnex = knex(TestDbMngr.getMetaDbConfig());
    await TestDbMngr.useDatabase(TestDbMngr.metaKnex, TestDbMngr.dbName);
  }

  static async setupSakila() {
    if (TestDbMngr.sakilaKnex) {
      await TestDbMngr.sakilaKnex.destroy();
    }

    if (TestDbMngr.isSqlite()) {
      await TestDbMngr.seedSakila();
      TestDbMngr.sakilaKnex = knex(TestDbMngr.getSakilaDbConfig());
      return;
    }

    TestDbMngr.sakilaKnex = knex(TestDbMngr.getDbConfigWithNoDb());
    await TestDbMngr.resetDatabase(
      TestDbMngr.sakilaKnex,
      TestDbMngr.sakilaDbName,
    );
    await TestDbMngr.sakilaKnex.destroy();

    TestDbMngr.sakilaKnex = knex(TestDbMngr.getSakilaDbConfig());
    await TestDbMngr.useDatabase(
      TestDbMngr.sakilaKnex,
      TestDbMngr.sakilaDbName,
    );
  }

  static async switchToSqlite() {
    // process.env[`DATABASE_URL`] = `sqlite3:///?database=${__dirname}/${TestDbMngr.dbName}.sqlite`;
    TestDbMngr.dbConfig = {
      client: 'sqlite3',
      connection: {
        filename: `${__dirname}/${TestDbMngr.dbName}.db`,
        database: TestDbMngr.dbName,
      },
      useNullAsDefault: true,
      meta: {
        tn: 'nc_evolutions',
        dbAlias: 'db',
        api: {
          type: 'rest',
          prefix: '',
          graphqlDepthLimit: 10,
        },
        inflection: {
          tn: 'camelize',
          cn: 'camelize',
        },
      },
    };

    process.env[
      `NC_DB`
    ] = `sqlite3:///?database=${__dirname}/${TestDbMngr.dbName}.db`;
    await TestDbMngr.setupMeta();
    await TestDbMngr.setupSakila();
  }

  private static async resetDatabase(knexClient, dbName) {
    if (TestDbMngr.isSqlite()) {
      // return knexClient.raw(`DELETE FROM sqlite_sequence`);
    } else {
      try {
        await knexClient.raw(`DROP DATABASE ${dbName}`);
      } catch (e) {}
      await knexClient.raw(`CREATE DATABASE ${dbName}`);
      console.log(`Database ${dbName} created`);

      if (!TestDbMngr.isPg()) {
        await knexClient.raw(`USE ${dbName}`);
      }
    }
  }

  static isSqlite() {
    return TestDbMngr.dbConfig.client === 'sqlite3';
  }

  static isPg() {
    return TestDbMngr.dbConfig.client === 'pg';
  }

  private static async useDatabase(knexClient, dbName) {
    if (!TestDbMngr.isSqlite() && !TestDbMngr.isPg()) {
      await knexClient.raw(`USE ${dbName}`);
    }
  }

  static getDbConfigWithNoDb() {
    const dbConfig = JSON.parse(JSON.stringify(TestDbMngr.dbConfig));
    delete dbConfig.connection.database;
    return dbConfig;
  }

  static getMetaDbConfig() {
    return TestDbMngr.dbConfig;
  }

  private static resetMetaSqlite() {
    if (fs.existsSync(`${__dirname}/test_meta.db`)) {
      fs.unlinkSync(`${__dirname}/test_meta.db`);
    }
  }

  static getSakilaDbConfig() {
    const sakilaDbConfig = JSON.parse(JSON.stringify(TestDbMngr.dbConfig));
    sakilaDbConfig.connection.database = TestDbMngr.sakilaDbName;
    sakilaDbConfig.connection.multipleStatements = true;
    if (TestDbMngr.isSqlite()) {
      sakilaDbConfig.connection.filename = `${__dirname}/test_sakila.db`;
    }
    return sakilaDbConfig;
  }

  static async seedSakila() {
    const testsDir = __dirname.replace('tests/unit', 'tests');

    if (TestDbMngr.isSqlite()) {
      if (fs.existsSync(`${__dirname}/test_sakila.db`)) {
        fs.unlinkSync(`${__dirname}/test_sakila.db`);
      }
      fs.copyFileSync(
        `${testsDir}/sqlite-sakila-db/sakila.db`,
        `${__dirname}/test_sakila.db`,
      );
    } else if (TestDbMngr.isPg()) {
      const schemaFile = fs
        .readFileSync(`${testsDir}/pg-sakila-db/01-postgres-sakila-schema.sql`)
        .toString();
      const dataFile = fs
        .readFileSync(
          `${testsDir}/pg-sakila-db/02-postgres-sakila-insert-data.sql`,
        )
        .toString();
      await TestDbMngr.sakilaKnex.raw(schemaFile);
      await TestDbMngr.sakilaKnex.raw(dataFile);
    } else {
      const schemaFile = fs
        .readFileSync(`${testsDir}/mysql-sakila-db/03-test-sakila-schema.sql`)
        .toString();
      const dataFile = fs
        .readFileSync(`${testsDir}/mysql-sakila-db/04-test-sakila-data.sql`)
        .toString();
      await TestDbMngr.sakilaKnex.raw(schemaFile);
      await TestDbMngr.sakilaKnex.raw(dataFile);
    }
  }

  static async disableForeignKeyChecks(knexClient) {
    if (TestDbMngr.isSqlite()) {
      await knexClient.raw('PRAGMA foreign_keys = OFF');
    } else if (TestDbMngr.isPg()) {
      await knexClient.raw(`SET session_replication_role = 'replica'`);
    } else {
      await knexClient.raw(`SET FOREIGN_KEY_CHECKS = 0`);
    }
  }

  static async enableForeignKeyChecks(knexClient) {
    if (TestDbMngr.isSqlite()) {
      await knexClient.raw(`PRAGMA foreign_keys = ON;`);
    } else if (TestDbMngr.isPg()) {
      await knexClient.raw(`SET session_replication_role = 'origin'`);
    } else {
      await knexClient.raw(`SET FOREIGN_KEY_CHECKS = 1`);
    }
  }

  static async showAllTables(knexClient) {
    if (TestDbMngr.isSqlite()) {
      const tables = await knexClient.raw(
        `SELECT name FROM sqlite_master WHERE type='table'`,
      );
      return tables
        .filter((t) => t.name !== 'sqlite_sequence' && t.name !== '_evolutions')
        .map((t) => t.name);
    } else if (TestDbMngr.isPg()) {
      const tables = await knexClient.raw(
        `SELECT tablename FROM pg_catalog.pg_tables WHERE schemaname != 'pg_catalog' AND schemaname != 'information_schema';`,
      );
      return tables.rows.map((t) => t.tablename);
    } else {
      const response = await knexClient.raw(`SHOW TABLES`);
      return response[0].map((table) => Object.values(table)[0]);
    }
  }
}