using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using FirebirdSql.Data.FirebirdClient;

namespace FireBirdUtil.SqlUtils
{
	public static class SQLExecuteUtil_Transaction
	{//TODO:是否增加方法：用FbCommand参数，替代FbConnection参数的方法
		/// <summary>
		/// 在事务中：插入数据
		/// </summary>
		/// <param name="conn">连接.在调用该方法之前，应该已打开</param>
		/// <param name="tr">事务</param>
		/// <param name="tableName">表名</param>
		/// <param name="fieldsValues">一条数据的信息</param>
		public static void Insert(FbConnection conn, FbTransaction tr, string tableName, IDictionary<string, object> fieldsValues)
		{
			var insertSql = SqlUtil.GetInsertSql(tableName, fieldsValues);
			SqlExecuteBaseUtil.ExecuteNonQuery(conn, tr, insertSql);
		}

		/// <summary>
		/// 在事务中：删除符合条件的数据
		/// </summary>
		/// <param name="conn">连接.在调用该方法之前，应该已打开</param>
		/// <param name="tr">事务</param>
		/// <param name="tableName">表名</param>
		/// <param name="conditions">以where打头的条件</param>
		public static void Delete(FbConnection conn, FbTransaction tr, string tableName, string conditions)
		{
			var deleteSql = SqlUtil.GetDeleteSql(tableName, conditions);
			SqlExecuteBaseUtil.ExecuteNonQuery(conn, tr, deleteSql);
		}

		/// <summary>
		/// 在事务中：更新符合条件的数据
		/// </summary>
		/// <param name="conn">连接.在调用该方法之前，应该已打开</param>
		/// <param name="tr">事务</param>
		/// <param name="tableName">表名</param>
		/// <param name="newValues">新值：Key为字段名，Value为新值</param>
		/// <param name="conditions">以where打头的条件</param>
		public static void Update(FbConnection conn, FbTransaction tr, string tableName, Dictionary<string, object> newValues, string conditions)
		{
			var updateSql = SqlUtil.GetUpdateSql(tableName, newValues, conditions);
			SqlExecuteBaseUtil.ExecuteNonQuery(conn, tr, updateSql);
		}

		/// <summary>
		/// 在事务中：如果指定数据库中，不存在指定的表，则根据创建表的参数，创建之
		/// </summary>
		/// <param name="conn">连接.在调用该方法之前，应该已打开</param>
		/// <param name="tr">事务</param>
		/// <param name="tableName">表名</param>
		/// <param name="tableParams">创建表的字段的相关参数信息</param>
		public static void CreateTableIfNotExist(FbConnection conn, FbTransaction tr, string tableName, string tableParams)
		{
			if (IsTableExist(conn, tr, tableName))
				return;
			CreateTable(conn, tr, tableName, tableParams);
		}

		/// <summary>
		/// 在事务中：在指定数据库中，判断表是否存在
		/// </summary>
		/// <param name="conn">连接.在调用该方法之前，应该已打开</param>
		/// <param name="tr">事务</param>
		/// <param name="tableName">表名</param>
		public static bool IsTableExist(FbConnection conn, FbTransaction tr, string tableName)
		{
			return SqlExecuteBaseUtil.ExecuteScalar<bool>(conn, tr, SqlUtil.GetJudgeTableExistSql(tableName), obj => {
				int count = 0;
				if (obj.Equals(null) || obj.Equals(System.DBNull.Value)) {
					count = -1;
				} else {
					count = (int)obj;
				}
				return count > 0;
			});
		}

		/// <summary>
		/// 在事务中：在指定数据库中，创建数据表
		/// </summary>
		/// <param name="conn">连接.在调用该方法之前，应该已打开</param>
		/// <param name="tr">事务</param>
		/// <param name="tableName">表名</param>
		/// <param name="tableParams">创建表的字段的相关参数信息</param>
		public static void CreateTable(FbConnection conn, FbTransaction tr, string tableName, string tableParams)
		{
			string strSQL = SqlUtil.GetCreateTableSql(tableName, tableParams);
			SqlExecuteBaseUtil.ExecuteNonQuery(conn, tr, strSQL);
		}

	}
}