module db.db;

import slf4d;

import ddbc.core;

enum DBConnector {
  DB_MYSQL,
  DB_PGSQL,
  DB_SQLITE,
}

struct DBSettings {
  DBConnector connector;
  string host;
  ushort port;
  string username;
  string password;
  string dbname;
}

class DB {
  protected DBSettings m_settings;
  protected DataSource m_ds;
  protected Connection m_conn;
  protected Statement m_stmt = null;

  this(DBSettings settings) {
    this.m_settings = settings;
  }

  static DB getDB(DBSettings settings) {
    switch (settings.connector) {
    case DBConnector.DB_PGSQL:
      import db.pgsql;

      debugF!"DB type is PostgreSQL";
      return new PostgresDB(settings);

    default:
      throw new Exception("DB not supported");
    }
  }

  protected abstract DataSource getDataSource();

  void connect() {
    this.m_ds = this.getDataSource();
    this.m_conn = this.m_ds.getConnection();
    this.m_conn.setAutoCommit(false);
  }

  int runUpdate(string statement) {
    if (this.m_stmt is null)
      this.m_stmt = this.m_conn.createStatement();

    debugF!"Running update: %s"(statement);

    return this.m_stmt.executeUpdate(statement);
  }

  ResultSet runQuery(string statement) {
    if (this.m_stmt is null)
      this.m_stmt = this.m_conn.createStatement();

    debugF!"Running query: %s"(statement);

    return this.m_stmt.executeQuery(statement);
  }

  void runMigrations() {
    ResultSet rs = this.runQuery(
      `select * from information_schema.tables where table_name = 'migrations';`,
    );

    bool exists = rs.next();
    int ret = 0;

    if (exists == false) {
      ret |= this.runUpdate(
        `create table migrations(
          id serial,
          name character varying
        )`,
      );
    }
  }
}