using System;
using System.Data;
using Npgsql;
using CnasSynchrousModel;

namespace CnasSynchronusDAL
{
    public class PostgreSqlDAL : IDAL
    {
        private string connectionString;

        public PostgreSqlDAL(InstrumentDataSourceInfo dataSourceInfo)
        {
            connectionString = $"Server={dataSourceInfo.Host};Port={dataSourceInfo.Port};Database={dataSourceInfo.ServerName};User Id={dataSourceInfo.UserId};Password={dataSourceInfo.UserPwd};";
        }

        public bool TestConnection()
        {
            try
            {
                using (NpgsqlConnection conn = new NpgsqlConnection(connectionString))
                {
                    conn.Open();
                    return true;
                }
            }
            catch
            {
                return false;
            }
        }

        public DataTable GetDataTable(string sql)
        {
            DataTable dt = new DataTable();
            try
            {
                using (NpgsqlConnection conn = new NpgsqlConnection(connectionString))
                {
                    conn.Open();
                    using (NpgsqlCommand cmd = new NpgsqlCommand(sql, conn))
                    {
                        using (NpgsqlDataAdapter adapter = new NpgsqlDataAdapter(cmd))
                        {
                            adapter.Fill(dt);
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                throw new Exception($"获取数据失败：{ex.Message}");
            }
            return dt;
        }

        public DataSet GetDataSet(string sql)
        {
            DataSet ds = new DataSet();
            try
            {
                using (NpgsqlConnection conn = new NpgsqlConnection(connectionString))
                {
                    conn.Open();
                    using (NpgsqlCommand cmd = new NpgsqlCommand(sql, conn))
                    {
                        using (NpgsqlDataAdapter adapter = new NpgsqlDataAdapter(cmd))
                        {
                            adapter.Fill(ds);
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                throw new Exception($"获取数据失败：{ex.Message}");
            }
            return ds;
        }

        public int ExecuteNonQuery(string sql)
        {
            try
            {
                using (NpgsqlConnection conn = new NpgsqlConnection(connectionString))
                {
                    conn.Open();
                    using (NpgsqlCommand cmd = new NpgsqlCommand(sql, conn))
                    {
                        return cmd.ExecuteNonQuery();
                    }
                }
            }
            catch (Exception ex)
            {
                throw new Exception($"执行SQL失败：{ex.Message}");
            }
        }

        public object ExecuteScalar(string sql)
        {
            try
            {
                using (NpgsqlConnection conn = new NpgsqlConnection(connectionString))
                {
                    conn.Open();
                    using (NpgsqlCommand cmd = new NpgsqlCommand(sql, conn))
                    {
                        return cmd.ExecuteScalar();
                    }
                }
            }
            catch (Exception ex)
            {
                throw new Exception($"执行SQL失败：{ex.Message}");
            }
        }

        public bool ExecuteTransaction(string[] sqlArray)
        {
            using (NpgsqlConnection conn = new NpgsqlConnection(connectionString))
            {
                conn.Open();
                using (NpgsqlTransaction transaction = conn.BeginTransaction())
                {
                    try
                    {
                        foreach (string sql in sqlArray)
                        {
                            using (NpgsqlCommand cmd = new NpgsqlCommand(sql, conn, transaction))
                            {
                                cmd.ExecuteNonQuery();
                            }
                        }
                        transaction.Commit();
                        return true;
                    }
                    catch (Exception ex)
                    {
                        transaction.Rollback();
                        throw new Exception($"执行事务失败：{ex.Message}");
                    }
                }
            }
        }

        public void BulkCopy(DataTable sourceData, string targetTable)
        {
            try
            {
                using (NpgsqlConnection conn = new NpgsqlConnection(connectionString))
                {
                    conn.Open();
                    
                    // 构建COPY命令
                    using (var writer = conn.BeginBinaryImport($"COPY {targetTable} FROM STDIN (FORMAT BINARY)"))
                    {
                        foreach (DataRow row in sourceData.Rows)
                        {
                            writer.StartRow();
                            for (int i = 0; i < sourceData.Columns.Count; i++)
                            {
                                if (row[i] == DBNull.Value)
                                    writer.WriteNull();
                                else
                                    writer.Write(row[i]);
                            }
                        }
                        writer.Complete();
                    }
                }
            }
            catch (Exception ex)
            {
                throw new Exception($"批量复制数据失败：{ex.Message}");
            }
        }

        public void Dispose()
        {
            // 清理资源
            GC.SuppressFinalize(this);
        }
    }
}