using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace PRSDesktop;

public abstract class MicrosoftSQLClient : IDisposable
{
    private SqlConnection? connection;

    protected abstract string GetConnectionString();

    public bool Connect()
    {
        connection = new SqlConnection(GetConnectionString());
        try
        {
            connection.Open();
        }
        catch (Exception e)
        {
            connection = null;
        }
        return IsConnected;
    }

    public bool IsConnected => connection != null;

    public void Disconnect()
    {
        if (connection != null)
        {
            connection.Dispose();
            connection = null;
        }
    }

    public DataTable Query(string sql, string tablename, SqlParameter[]? parameters = null)
    {
        var result = new DataTable(tablename);
        if (connection != null)
        {
            using (var _command = new SqlCommand(sql.Replace("\r\n"," ").Replace("\n"," ").Replace("\r"," "), connection))
            {
                if (parameters is not null)
                {
                    foreach (var _parameter in parameters)
                        _command.Parameters.Add(_parameter);
                }

                using var _adapter = new SqlDataAdapter(_command);
                _adapter.Fill(result);
            }
            connection.Close();
        }

        return result;
    }

    public int ExecuteSQL(string sql, SqlParameter[]? parameters = null)
    {
        int result = 0;
        if(connection != null)
        {
            using(var command = new SqlCommand(sql.Replace("\r\n"," ").Replace("\n", " ").Replace("\r"," "), connection))
            {
                if (parameters is not null)
                {
                    foreach (var _parameter in parameters)
                        command.Parameters.Add(_parameter);
                }

                result = command.ExecuteNonQuery();
            }

            connection.Close();
        }
        return result;
    }

    public static int GetInteger(DataRow row, string field, int defaultvalue = 0)
    {
        return row[field] == DBNull.Value ? 0 : Convert.ToInt32(row[field]);
    }
    
    public static double GetDouble(DataRow row, string field, double defaultvalue = 0.0)
    {
        return row[field] == DBNull.Value
            ? 0.0
            : Convert.ToDouble(row[field]);
    }

    public static string GetString(DataRow row, string field, string defaultvalue = "")
    {
        return row[field] == DBNull.Value ? "" : row[field] as string ?? defaultvalue;
    }
    
    public static byte[] GetBinary(DataRow row, string field)
    {
        return row[field] == DBNull.Value ? [] : (byte[])row[field];
    }

    public void Dispose()
    {
        Disconnect();
    }
}