//	Spludlow Software
//	Copyright © Samuel P. Ludlow 2020 All Rights Reserved
//	Distributed under the terms of the GNU General Public License version 3
//	Distributed WITHOUT ANY WARRANTY; without implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE
//	https://www.spludlow.co.uk/LICENCE.TXT
//	The Spludlow logo is a registered trademark of Samuel P. Ludlow and may not be used without permission
//	v1.14

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using System.IO;
using System.Data;

namespace Spludlow.Video
{
	/// <summary>
	///	Very simple PVR demo
	///	
	///	Call SubmitRecording() method, it will drop a file
	///	
	///	The "Run" method will pick up dropped files & start VLC recording for a specific duration when required.
	///	
	///	Ensure "Run" thead is running (line in Spludlow-Service.txt)
	///	Method	VideoRecorder	Spludlow		Spludlow.Video.Recorder		Run
	///	
	///	Make sure config set: "VideoRecorder.Directory" and have permissions to directory
	/// </summary>
	public class Recorder
	{
		private string RecordDirectory;
		private string SubmitDirectory;
		private string ScheduleFilename;

		private int TickMilliSeconds = 10 * 1000;

		public DataTable Schedule;

		public Recorder()
		{
			this.Load(false);
		}

		public Recorder(bool dontLoad)
		{
			this.Load(dontLoad);
		}

		public DataTable NewScheduleTable()
		{
			return Spludlow.Data.TextTable.ReadText(new string[]
			{
				"Number		StartTime	EndTime		Filename	Frequency	ServiceId",
				"Int32*		DateTime*	DateTime	String		Int32		Int32",
			});
		}

		public void Load(bool dontLoad)
		{
			this.RecordDirectory = Spludlow.Config.Get("VideoRecorder.Directory");
			this.SubmitDirectory = this.RecordDirectory + @"\Submit";
			this.ScheduleFilename = this.RecordDirectory + @"\Schedule.txt";

			if (dontLoad == true)
				return;

			if (Directory.Exists(this.RecordDirectory) == false)
				Directory.CreateDirectory(this.RecordDirectory);

			if (Directory.Exists(this.SubmitDirectory) == false)
				Directory.CreateDirectory(this.SubmitDirectory);

			if (File.Exists(this.ScheduleFilename) == false)
			{
				this.Schedule = this.NewScheduleTable();
				Spludlow.Data.TextTable.Write(this.ScheduleFilename, this.Schedule);
			}

			this.Schedule = Spludlow.Data.TextTable.ReadFile(this.ScheduleFilename);
		}

		public void SubmitRecording(DataRow channel, DataRow programme)
		{
			int channelNumber = (int)channel["Number"];
			DateTime startTime = (DateTime)programme["StartDate"];
			DateTime endTime = (DateTime)programme["EndDate"];
			string channelName = (string)channel["Name"];
			string programmeTitle = (string)programme["Title"];
			int frequency = (int)channel["Frequency"];
			int serviceId = (int)channel["ServiceId"];

			this.SubmitRecording(channelNumber, startTime, endTime, channelName, programmeTitle, frequency, serviceId);
		}

		public void SubmitRecording(int channelNumber, DateTime startTime, DateTime endTime, string channelName, string programmeTitle, int frequency, int serviceId)
		{
			startTime = TruncateToMinutes(startTime);

			channelName = FixName(channelName);
			programmeTitle = FixName(programmeTitle);

			StringBuilder text = new StringBuilder();
			text.Append(startTime.ToString("yyyy-MM-dd_HH-mm"));
			text.Append("_");
			text.Append(channelNumber);
			text.Append("_");
			text.Append(Spludlow.Io.Paths.LegalFileName(channelName));
			text.Append("_");
			text.Append(Spludlow.Io.Paths.LegalFileName(programmeTitle));

			string filename = text.ToString();

			DataTable table = this.NewScheduleTable();

			table.Rows.Add(new object[] { channelNumber, startTime, endTime, filename, frequency, serviceId });

			Spludlow.Data.TextTable.Write(this.SubmitDirectory + @"\" + filename + ".txt", table);
		}

		private static string FixName(string name)
		{
			name = name.Replace('\'', '_');
			name = name.Replace('"', '_');
			return name;
		}

		private System.Threading.EventWaitHandle WaitFinished = null;

		public void Run()
		{
			this.WaitFinished = new System.Threading.EventWaitHandle(false, System.Threading.EventResetMode.ManualReset);

			Spludlow.Log.Report("VideoRecorder; Starting", new object[] { this.Schedule });

			while (this.WaitFinished.WaitOne(this.TickMilliSeconds) == false)
			{
				int changes = 0;

				changes += this.CheckSubmit();

				changes += this.CheckSchedule();

				if (changes > 0)
				{
					Spludlow.Data.TextTable.Write(this.ScheduleFilename, this.Schedule);
					Spludlow.Log.Info("VideoRecorder; Changes:\t" + changes, new object[] { this.Schedule });
				}
			}

			Spludlow.Log.Finish("VideoRecorder; Clean Exit", new object[] { this.Schedule });
		}

		public void Stop()
		{
			this.WaitFinished.Set();
		}

		private int CheckSubmit()
		{
			int changeCount = 0;

			foreach (string filename in Directory.GetFiles(this.SubmitDirectory, "*.txt"))
			{
				if (Spludlow.Io.Files.IsOpen(filename) == true)
					continue;

				DataTable importTable = Spludlow.Data.TextTable.ReadFile(filename);

				foreach (DataRow row in importTable.Rows)
				{

					this.Schedule.ImportRow(row);

					Spludlow.Log.Info("VideoRecorder; Import Recording:\t" + (string)row["Filename"]);

					++changeCount;
				}

				File.Delete(filename);
			}

			return changeCount;
		}

		private int CheckSchedule()
		{
			DateTime nowTime = TruncateToMinutes(DateTime.Now);

			List<DataRow> removeList = new List<DataRow>();

			foreach (DataRow row in this.Schedule.Rows)
			{
				DateTime startTime = (DateTime)row["StartTime"];
				DateTime endTime = (DateTime)row["EndTime"];

				if (nowTime >= startTime)
				{
					string filename = (string)row["Filename"];

					int durationMinutes = (int)(endTime - nowTime).TotalMinutes;

					if (nowTime < endTime && durationMinutes > 0)
					{
						int frequency = (int)row["Frequency"];
						int serviceId = (int)row["ServiceId"];

						filename = this.RecordDirectory + @"\" + filename + ".ts";

						Spludlow.VLC.StartRecording(filename, durationMinutes * 60, frequency, serviceId);

						Spludlow.Log.Report("VideoRecorder; Started Recording:\t" + filename);
					}
					else
					{
						Spludlow.Log.Warning("VideoRecorder; Missed Recording:\t" + filename);
					}

					removeList.Add(row);
				}
			}

			foreach (DataRow row in removeList)
				row.Delete();
			this.Schedule.AcceptChanges();

			return removeList.Count;
		}

		public static DateTime TruncateToMinutes(DateTime dateTime)
		{
			return new DateTime(dateTime.Year, dateTime.Month, dateTime.Day, dateTime.Hour, dateTime.Minute, 0);
		}

	}
}