#region ================== Copyright (c) 2007 Pascal vd Heiden

/*
 * Copyright (c) 2007 Pascal vd Heiden, www.codeimp.com
 * This program is released under GNU General Public License
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 */

#endregion

#region ================== Namespaces

using System;
using System.Collections;
using System.Collections.Generic;
using System.Globalization;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Reflection;
using CodeImp.DoomBuilder.Windows;
using CodeImp.DoomBuilder.IO;
using CodeImp.DoomBuilder.Map;
using CodeImp.DoomBuilder.Rendering;
using CodeImp.DoomBuilder.Geometry;
using CodeImp.DoomBuilder.Editing;
using CodeImp.DoomBuilder.Actions;
using CodeImp.DoomBuilder.Types;
using CodeImp.DoomBuilder.Config;
using System.Threading;

#endregion

namespace CodeImp.DoomBuilder.BuilderModes
{
	[ErrorChecker("Check overlapping lines", true, 500)]
	public class CheckOverlappingLines : ErrorChecker
	{
		#region ================== Constants

		#endregion

		#region ================== Constructor / Destructor

		// Constructor
		public CheckOverlappingLines()
		{
			// Total progress is done when all lines are checked
			SetTotalProgress(General.Map.Map.Linedefs.Count);
		}
		
		#endregion
		
		#region ================== Methods
		
		// This runs the check
		public override void Run()
		{
			Dictionary<Linedef, Linedef> donelines = new Dictionary<Linedef, Linedef>();
			
			// Go for all the liendefs
			foreach(Linedef l in General.Map.Map.Linedefs)
			{
				// Check if not already done
				if(!donelines.ContainsKey(l))
				{
					// And go for all the linedefs that could overlap
					foreach(Linedef d in General.Map.Map.Linedefs)
					{
						// Not the same line?
						if(!object.ReferenceEquals(l, d))
						{
							float lu, du;

							// Check if the lines touch. Note that I don't include 0.0 and 1.0 here because
							// the lines may be touching at the ends when sharing the same vertex.
							if(l.Line.GetIntersection(d.Line, out du, out lu))
							{
								if((lu > 0.0f) && (lu < 1.0f) && (du > 0.0f) && (du < 1.0f))
								{
									// Check if not the same sector on all sides
									Sector samesector = null;
									if(l.Front != null) samesector = l.Front.Sector;
									else if(l.Back != null) samesector = l.Back.Sector;
									else if(d.Front != null) samesector = d.Front.Sector;
									else if(d.Back != null) samesector = d.Back.Sector;
									if((l.Front == null) || (l.Front.Sector != samesector)) samesector = null;
									else if((l.Back == null) || (l.Back.Sector != samesector)) samesector = null;
									else if((d.Front == null) || (d.Front.Sector != samesector)) samesector = null;
									else if((d.Back == null) || (d.Back.Sector != samesector)) samesector = null;

									if(samesector == null)
									{
										SubmitResult(new ResultLineOverlapping(l, d));
										donelines[d] = d;
									}
								}
							}
						}
					}
				}
				
				// Handle thread interruption
				try { Thread.Sleep(0); }
				catch(ThreadInterruptedException) { return; }
				
				// We are making progress!
				AddProgress(1);
			}
		}
		
		#endregion
	}
}