using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;
using PartSource.Automation.Models.Configuration;
using PartSource.Automation.Models.Enums;
using PartSource.Automation.Services;
using Ratermania.Automation.Interfaces;
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.IO.Compression;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace PartSource.Automation.Jobs
{
	public class ProcessWhiFitment : IAutomationJob
	{
		private readonly ILogger<ProcessWhiFitment> _logger;
		private readonly WhiSeoService _whiSeoService;
		private readonly FtpConfiguration _ftpConfiguration;
		private readonly SeoDataType _seoDataType;

		public ProcessWhiFitment(IConfiguration configuration, ILogger<ProcessWhiFitment> logger, WhiSeoService whiSeoService)
		{
			_logger = logger;
			_whiSeoService = whiSeoService;

			_seoDataType = SeoDataType.Fitment;

			_ftpConfiguration = configuration.GetSection("ftpServers:WhiConfiguration").Get<FtpConfiguration>();
		}

		public async Task Run()
		{
			_whiSeoService.Truncate(_seoDataType);
			_whiSeoService.GetFiles(_seoDataType);

			string directory = Path.Combine(_ftpConfiguration.Destination, _seoDataType.ToString().ToLowerInvariant());
			DirectoryInfo directoryInfo = new DirectoryInfo(directory);

			foreach (FileInfo fileInfo in directoryInfo.GetFiles())
			{
				if (!fileInfo.Name.EndsWith("csv.gz"))
				{
					continue;
				}

				string filename = Decompress(fileInfo);

				using DataTable dataTable = new DataTable();
				dataTable.Columns.Add("LineCode", typeof(string));
				dataTable.Columns.Add("PartNumber", typeof(string));
				dataTable.Columns.Add("BaseVehicleId", typeof(int));
				dataTable.Columns.Add("EngineConfigId", typeof(int));
				dataTable.Columns.Add("Position", typeof(string));
				dataTable.Columns.Add("NoteText", typeof(string));

				using StreamReader reader = new StreamReader(filename);
				string line = reader.ReadLine(); // Burn the header row

				try
				{
					int skippedLines = 0;
					while (reader.Peek() > 0)
					{
						line = reader.ReadLine();

						string[] columns = line.Replace("\"", string.Empty).Split(',');

						if (columns.Length != 8)
						{
							skippedLines++;
							continue;
						}

						string lineCode = Regex.Replace(columns[0], "[^a-zA-Z0-9]", string.Empty).Trim();
						string partNumber = Regex.Replace(columns[1], "[^a-zA-Z0-9]", string.Empty).Trim();
						string position = columns[7].Trim();
						string noteText = columns[4].Trim();

						if (!string.IsNullOrEmpty(lineCode)
							&& !string.IsNullOrEmpty(partNumber)
							&& int.TryParse(columns[5], out int baseVehicleId)
							&& int.TryParse(columns[6], out int engineConfigId))
						{
							dataTable.Rows.Add(new object[] { lineCode, partNumber, baseVehicleId, engineConfigId, position, noteText });
						}
					}

					_whiSeoService.BulkCopy(_seoDataType, dataTable);

					if (skippedLines == 0)
					{
						_logger.LogInformation($"Copied {filename} to the database.");
					}

					else
					{
						_logger.LogWarning($"Copied {filename} to the database with warnings.  {skippedLines} lines contained errors and could not be processed.");
					}
				}

				catch (Exception ex)
				{
					_logger.LogError($"Failed to copy {filename} to the database.", ex);
				}

				try
				{
					reader.Close();

					File.Delete(filename);
					File.Delete(fileInfo.FullName);
				}

				catch (Exception ex)
				{
					_logger.LogWarning($"Failed to delete {filename}.  This file will need to be deleted manually.", ex);
				}
			}
		}

		public string Decompress(FileInfo fileInfo)
		{
			string decompressedFile = fileInfo.FullName.Remove(fileInfo.FullName.Length - fileInfo.Extension.Length);

			using FileStream filestream = File.Create(decompressedFile);
			using GZipStream decompressionStream = new GZipStream(fileInfo.OpenRead(), CompressionMode.Decompress);
			
			decompressionStream.CopyTo(filestream);

			return decompressedFile;
		}
	}
}