using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using MySql.Data.MySqlClient;

namespace Kelsier {
    class Database {
        public MySqlConnection dbh { get; private set; }

        private string dbinfo;


        /// <summary>
        /// Construct a Database, using the MySQL connector string.
        /// </summary>
        /// <param name="dbinfo">Connector string</param>
        public Database(string dbinfo) {
            this.dbinfo = dbinfo;

            dbh = new MySqlConnection(this.dbinfo);
            dbh.Open();
        }
        public Database(Database copy) {
            this.dbinfo = copy.dbinfo;

            dbh = new MySqlConnection(this.dbinfo);
            dbh.Open();
        }

        ~Database() {
            dbh.Close();
        }

        public int execute(string query) {
            MySqlCommand cmdo = new MySqlCommand(query, dbh);
            return cmdo.ExecuteNonQuery();
        }
        public int execute(string query, object[] keys) {
            MySqlCommand cmdo = new MySqlCommand();
            cmdo.Connection = dbh;
            cmdo.CommandText = query;
            cmdo.Prepare();

            for (int i = 0; i < keys.Length; i += 2) {
                cmdo.Parameters.AddWithValue(keys[i].ToString(), keys[i + 1]);
            }

            return cmdo.ExecuteNonQuery();
        }

        public object queryScalar(string query) {
            MySqlCommand cmdo = new MySqlCommand(query, dbh);
            return cmdo.ExecuteScalar();
        }
        public object queryScalar(string query, object[] keys) {
            MySqlCommand cmdo = new MySqlCommand();
            cmdo.Connection = dbh;
            cmdo.CommandText = query;
            cmdo.Prepare();

            for (int i = 0; i < keys.Length; i += 2) {
                cmdo.Parameters.AddWithValue(keys[i].ToString(), keys[i + 1]);
            }

            return cmdo.ExecuteScalar();
        }

        public MySqlDataReader queryReader(string query) {
            MySqlCommand cmdo = new MySqlCommand(query, dbh);
            return cmdo.ExecuteReader();
        }
        public MySqlDataReader queryReader(string query, object[] keys) {
            if (keys.Length % 2 != 0) {
                throw new PlaceholdersException();
            }
            MySqlCommand cmdo = new MySqlCommand();
            cmdo.Connection = dbh;
            cmdo.CommandText = query;
            cmdo.Prepare();

            for (int i = 0; i < keys.Length; i += 2) {
                cmdo.Parameters.AddWithValue(keys[i].ToString(), keys[i + 1]);
            }
            return cmdo.ExecuteReader();
        }
    }

    class PlaceholdersException : Exception { }
}