using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Npgsql;
using NpgsqlTypes;

namespace TTSW.Utils
{
    public class MyDatabase : IMyDatabase
    {
        public IConfiguration Configuration { get; set; }

        public MyDatabase(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public DataTable ExecuteDataTableNpgsql(string queryString, List<NpgsqlParameter> para)
        {
            System.Data.DataSet ds = new DataSet();

            var DB_HOST = Environment.GetEnvironmentVariable("DB_HOST");
            var DB_PORT = Environment.GetEnvironmentVariable("DB_PORT");
            var DB_NAME = Environment.GetEnvironmentVariable("DB_NAME");
            var DB_USERNAME = Environment.GetEnvironmentVariable("DB_USERNAME");
            var DB_PASSWORD = Environment.GetEnvironmentVariable("DB_PASSWORD");

            var envConnectionString = $"Server={DB_HOST};Port={DB_PORT};Database={DB_NAME};User ID={DB_USERNAME};Password={DB_PASSWORD};";

            string connectionString = !string.IsNullOrEmpty(DB_HOST) ? envConnectionString : Configuration.GetConnectionString("externalDBConnectionString");

            using (NpgsqlConnection conn = new NpgsqlConnection(connectionString))
            using (NpgsqlCommand cmd = new NpgsqlCommand(queryString, conn))
            {
                if (para != null) cmd.Parameters.AddRange(para.ToArray());
                using (NpgsqlDataAdapter ad = new NpgsqlDataAdapter(cmd))
                {
                    ad.Fill(ds, "mytable");
                }
            }
            return ds.Tables["mytable"];
        }

        public int ExecuteNonQueryNpgsql(string queryString, List<NpgsqlParameter> para)
        {
            int rowAffected = -1;
            string connectionString = Configuration.GetConnectionString("externalDBConnectionString");

            using (NpgsqlConnection conn = new NpgsqlConnection(connectionString))
            using (NpgsqlCommand cmd = new NpgsqlCommand(queryString, conn))
            {
                conn.Open();
                if (para != null) cmd.Parameters.AddRange(para.ToArray());
                rowAffected = cmd.ExecuteNonQuery();
            }

            return rowAffected;
        }

        public string ExecuteScalarNpgsql(string queryString, List<NpgsqlParameter> para)
        {
            string result = "";
            string connectionString = Configuration.GetConnectionString("externalDBConnectionString");

            using (NpgsqlConnection conn = new NpgsqlConnection(connectionString))
            using (NpgsqlCommand cmd = new NpgsqlCommand(queryString, conn))
            {
                conn.Open();
                if (para != null) cmd.Parameters.AddRange(para.ToArray());
                result = cmd.ExecuteScalar().ToString();
            }

            return result;
        }

        public List<NpgsqlParameter> GetParameterListNpgsql()
        {
            return new List<NpgsqlParameter>();
        }

        public NpgsqlParameter GetParameterNpgsql(string name, NpgsqlDbType type, int size, object value)
        {
            var i = new NpgsqlParameter(name, type, size);
            i.Value = value;
            return i;
        }

        public NpgsqlParameter GetParameterNpgsql(string name, NpgsqlDbType type, object value)
        {
            var i = new NpgsqlParameter(name, type);
            i.Value = value;
            return i;
        }
    }
}