using MesETL.App.HostedServices;

namespace MesETL.App.Options;

public class DatabaseOutputOptions
{
    /// <summary>
    /// 输出数据库的连接字符串
    /// </summary>
    public string? ConnectionString { get; set; }

    /// <summary>
    /// MySql max_allowed_packet变量值大小
    /// </summary>
    public int MaxAllowedPacket { get; set; } = 32 * 1024 * 1024;

    /// <summary>
    /// 每次Insert提交的数据量
    /// </summary>
    public int FlushCount { get; set; } = 10000;

    /// <summary>
    /// 每个数据库最大提交任务数
    /// </summary>
    public int MaxDatabaseOutputTask { get; set; } = 4;

    /// <summary>
    /// 将json列作为16进制格式输出(0x前缀)
    /// </summary>
    public bool TreatJsonAsHex { get; set; } = true;

    /// <summary>
    /// 不对某些表进行输出
    /// </summary>
    public string[] NoOutput { get; set; } = [];
    
    /// <summary>
    /// <para>当某张表的键出现重复时，在输出时使用ON DUPLICATE KEY UPDATE更新该条记录</para>
    /// <para>表名为键，更新的字段为值</para>
    /// <example>
    /// <code>
    /// {
    ///     // 当order_data_parts表的键出现重复时，使用ON DUPLICATE KEY UPDATE更新已存在记录的CompanyID为新插入记录的值
    ///     "order_data_parts": "CompanyID = new.CompanyID"
    /// }
    /// </code>
    /// </example>
    /// </summary>
    public Dictionary<string, string>? ForUpdate { get; set; }

    /// <summary>
    /// 配置导入数据的特殊列，请在代码中配置
    /// </summary>
    public Dictionary<string, ColumnType> ColumnTypeConfig { get; set; } = new(); // "table.column" -> type
    
    /// <summary>
    /// 所有数据都输出完毕时的事件，请在代码中配置
    /// </summary>
    public Action<DataOutputContext>? OutputFinished { get; set; } 

    public ColumnType GetColumnType(string table, string column)
    {
        return ColumnTypeConfig.GetValueOrDefault(string.Concat(table, ".", column), ColumnType.UnDefine);
    }

    public bool TryGetForUpdate(string table, out string? forUpdate)
    {
        forUpdate = null;
        if (ForUpdate is null || !ForUpdate.TryGetValue(table, out forUpdate))
            return false;
        return true;
    }
}