//http://jasonjano.wordpress.com/2010/02/09/a-simple-c-wrapper-for-ffmpeg/

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.IO;
using System.Diagnostics;
using System.Configuration;
using System.Text.RegularExpressions;

namespace ffMpeg
{
	public class Converter
	{
		public static string _ffExe;
		public string WorkingPath; //i.e. temp

		public Converter()
		{
			Initialize();
		}

		#region Initialization
		private void Initialize()
		{
		}

		private string GetWorkingFile()
		{
			//try the stated directory
			if (File.Exists(_ffExe))
			{
				return _ffExe;
			}

			//oops, that didn't work, try the base directory
			if (File.Exists(Path.GetFileName(_ffExe)))
			{
				return Path.GetFileName(_ffExe);
			}

			//well, now we are really unlucky, let's just return null
			return null;
		}
		#endregion

		#region Get the File without creating a file lock
		public static System.Drawing.Image LoadImageFromFile(string fileName)
		{
			System.Drawing.Image theImage = null;
			using (FileStream fileStream = new FileStream(fileName, FileMode.Open,
			FileAccess.Read))
			{
				byte[] img;
				img = new byte[fileStream.Length];
				fileStream.Read(img, 0, img.Length);
				fileStream.Close();
				theImage = System.Drawing.Image.FromStream(new MemoryStream(img));
				img = null;
			}
			GC.Collect();
			return theImage;
		}

		public static MemoryStream LoadMemoryStreamFromFile(string fileName)
		{
			MemoryStream ms = null;
			using (FileStream fileStream = new FileStream(fileName, FileMode.Open,
			FileAccess.Read))
			{
				byte[] fil;
				fil = new byte[fileStream.Length];
				fileStream.Read(fil, 0, fil.Length);
				fileStream.Close();
				ms = new MemoryStream(fil);
			}
			GC.Collect();
			return ms;
		}
		#endregion

		#region Run the process
		private string RunProcess(string Parameters)
		{
			//create a process info
			ProcessStartInfo oInfo = new ProcessStartInfo(_ffExe, Parameters);
			oInfo.UseShellExecute = false;
			oInfo.CreateNoWindow = true;
			oInfo.RedirectStandardOutput = true;
			oInfo.RedirectStandardError = true;

			//Create the output and streamreader to get the output
			string output = null; StreamReader srOutput = null;

			//try the process
			try
			{
				//run the process
				Process proc = System.Diagnostics.Process.Start(oInfo);

				proc.WaitForExit();

				//get the output
				srOutput = proc.StandardError;

				//now put it in a string
				output = srOutput.ReadToEnd();

				proc.Close();
			}
			catch (Exception)
			{
				output = string.Empty;
			}
			finally
			{
				//now, if we succeded, close out the streamreader
				if (srOutput != null)
				{
					srOutput.Close();
					srOutput.Dispose();
				}
			}
			return output;
		}
		#endregion

		#region GetVideoInfo
		public VideoFile GetVideoInfo(MemoryStream inputFile, string Filename)
		{
			string tempfile = Path.Combine(this.WorkingPath, System.Guid.NewGuid().ToString() + Path.GetExtension(Filename));
			FileStream fs = File.Create(tempfile);
			inputFile.WriteTo(fs);
			fs.Flush();
			fs.Close();
			GC.Collect();

			VideoFile vf = null;
			try
			{
				vf = new VideoFile(tempfile);
			}
			catch (Exception ex)
			{
				throw ex;
			}

			GetVideoInfo(vf);

			try
			{
				File.Delete(tempfile);
			}
			catch (Exception)
			{

			}

			return vf;
		}
		public VideoFile GetVideoInfo(string inputPath)
		{
			VideoFile vf = null;
			try
			{
				vf = new VideoFile(inputPath);
			}
			catch (Exception ex)
			{
				throw ex;
			}
			GetVideoInfo(vf);
			return vf;
		}
		public void GetVideoInfo(VideoFile input)
		{
			//set up the parameters for video info
			string Params = string.Format("-i \"{0}\"", input.Path);
			string output = RunProcess(Params);
			input.RawInfo = output;

			//get duration
			Regex re = new Regex("[D|d]uration:.((\\d|:|\\.)*)");
			Match m = re.Match(input.RawInfo);

			if (m.Success)
			{
				string duration = m.Groups[1].Value;
				string[] timepieces = duration.Split(new char[] { ':', '.' });
				if (timepieces.Length == 4)
				{
					input.Duration = new TimeSpan(0, Convert.ToInt16(timepieces[0]), Convert.ToInt16(timepieces[1]), Convert.ToInt16(timepieces[2]), Convert.ToInt16(timepieces[3]));
				}
			}

			//get audio bit rate
			re = new Regex("[B|b]itrate:.((\\d|:)*)");
			m = re.Match(input.RawInfo);
			double kb = 0.0;
			if (m.Success)
			{
				Double.TryParse(m.Groups[1].Value, out kb);
			}
			input.BitRate = kb;

			//get the audio format
			re = new Regex("[A|a]udio:.*");
			m = re.Match(input.RawInfo);
			if (m.Success)
			{
				input.AudioFormat = m.Value;
			}

			//get the video format
			re = new Regex("[V|v]ideo:.*");
			m = re.Match(input.RawInfo);
			if (m.Success)
			{
				input.VideoFormat = m.Value;
			}

			//get the video format
			re = new Regex("(\\d{2,3})x(\\d{2,3})");
			m = re.Match(input.RawInfo);
			if (m.Success)
			{
				int width = 0; int height = 0;
				int.TryParse(m.Groups[1].Value, out width);
				int.TryParse(m.Groups[2].Value, out height);
				input.Width = width;
				input.Height = height;
			}
			input.infoGathered = true;
		}
		#endregion

		#region Convert to FLV
		public OutputPackage ConvertToFLV(MemoryStream inputFile, string Filename)
		{
			string tempfile = Path.Combine(this.WorkingPath, System.Guid.NewGuid().ToString() + Path.GetExtension(Filename));
			FileStream fs = File.Create(tempfile);
			inputFile.WriteTo(fs);
			fs.Flush();
			fs.Close();
			GC.Collect();

			VideoFile vf = null;
			try
			{
				vf = new VideoFile(tempfile);
			}
			catch (Exception ex)
			{
				throw ex;
			}

			OutputPackage oo = ConvertToFLV(vf);

			try
			{
				File.Delete(tempfile);
			}
			catch (Exception)
			{

			}

			return oo;
		}
		public OutputPackage ConvertToFLV(string inputPath)
		{
			VideoFile vf = null;
			try
			{
				vf = new VideoFile(inputPath);
			}
			catch (Exception ex)
			{
				throw ex;
			}

			OutputPackage oo = ConvertToFLV(vf);
			return oo;
		}
		public OutputPackage ConvertToFLV(VideoFile input)
		{
			if (!input.infoGathered)
			{
				GetVideoInfo(input);
			}
			OutputPackage ou = new OutputPackage();

			string filename = System.Guid.NewGuid().ToString() + ".flv";
			string finalpath = Path.Combine(this.WorkingPath, filename);
			string Params = string.Format("-i \"{0}\" -y -ar 22050 -ab 64 -f flv \"{1}\"", input.Path, finalpath);
			string output = RunProcess(Params);

			if (File.Exists(finalpath))
			{
				ou.VideoStream = LoadMemoryStreamFromFile(finalpath);
				try
				{
					File.Delete(finalpath);
				}
				catch (Exception) { }
			}
			return ou;
		}
		#endregion
	}

	public class VideoFile
	{
		#region Properties
		private string _Path;
		public string Path
		{
			get
			{
				return _Path;
			}
			set
			{
				_Path = value;
			}
		}

		public TimeSpan Duration { get; set; }
		public double BitRate { get; set; }
		public string AudioFormat { get; set; }
		public string VideoFormat { get; set; }
		public int Height { get; set; }
		public int Width { get; set; }
		public string RawInfo { get; set; }
		public bool infoGathered { get; set; }
		#endregion

		#region Constructors
		public VideoFile(string path)
		{
			_Path = path;
			Initialize();
		}
		#endregion

		#region Initialization
		private void Initialize()
		{
			this.infoGathered = false;
			//first make sure we have a value for the video file setting
			if (string.IsNullOrEmpty(_Path))
			{
				throw new Exception("Could not find the location of the video file");
			}

			//Now see if the video file exists
			if (!File.Exists(_Path))
			{
				throw new Exception("The video file " + _Path + " does not exist.");
			}
		}
		#endregion
	}

	public class OutputPackage
	{
		public MemoryStream VideoStream { get; set; }
		public System.Drawing.Image PreviewImage { get; set; }
		public string RawOutput { get; set; }
		public bool Success { get; set; }
	}
}