#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 System.Drawing;
using System.ComponentModel;
using CodeImp.DoomBuilder.Map;
using CodeImp.DoomBuilder.Geometry;
using System.Drawing.Imaging;
using CodeImp.DoomBuilder.Data;
using CodeImp.DoomBuilder.Editing;
using CodeImp.DoomBuilder.IO;
using CodeImp.DoomBuilder.Rendering;
using CodeImp.DoomBuilder.VisualModes;

#endregion

namespace CodeImp.DoomBuilder.GZDoomEditing
{
	internal sealed class VisualMiddleDouble : BaseVisualGeometrySidedef
	{
		#region ================== Constants

		#endregion

		#region ================== Variables

		private bool repeatmidtex;
		private Plane topclipplane;
		private Plane bottomclipplane;
		
		#endregion

		#region ================== Properties

		#endregion

		#region ================== Constructor / Setup

		// Constructor
		public VisualMiddleDouble(BaseVisualMode mode, VisualSector vs, Sidedef s) : base(mode, vs, s)
		{
			// Set render pass
			this.RenderPass = RenderPass.Mask;
			
			// We have no destructor
			GC.SuppressFinalize(this);
		}
		
		// This builds the geometry. Returns false when no geometry created.
		public override bool Setup()
		{
			Vector2D vl, vr;
			
			int lightvalue = Sidedef.Fields.GetValue("light", 0);
			bool lightabsolute = Sidedef.Fields.GetValue("lightabsolute", false);
			
			Vector2D tscale = new Vector2D(Sidedef.Fields.GetValue("scalex_mid", 1.0f),
										   Sidedef.Fields.GetValue("scaley_mid", 1.0f));
			Vector2D toffset = new Vector2D(Sidedef.Fields.GetValue("offsetx_mid", 0.0f),
											Sidedef.Fields.GetValue("offsety_mid", 0.0f));
			
			// Texture given?
			if((Sidedef.MiddleTexture.Length > 0) && (Sidedef.MiddleTexture[0] != '-'))
			{
				// Left and right vertices for this sidedef
				if(Sidedef.IsFront)
				{
					vl = new Vector2D(Sidedef.Line.Start.Position.x, Sidedef.Line.Start.Position.y);
					vr = new Vector2D(Sidedef.Line.End.Position.x, Sidedef.Line.End.Position.y);
				}
				else
				{
					vl = new Vector2D(Sidedef.Line.End.Position.x, Sidedef.Line.End.Position.y);
					vr = new Vector2D(Sidedef.Line.Start.Position.x, Sidedef.Line.Start.Position.y);
				}
				
				// Load sector data
				SectorData sd = mode.GetSectorData(Sidedef.Sector);
				SectorData osd = mode.GetSectorData(Sidedef.Other.Sector);
				if(!osd.Updated) osd.Update();
				
				// Texture given?
				if((Sidedef.MiddleTexture.Length > 0) && (Sidedef.MiddleTexture[0] != '-'))
				{
					// Load texture
					base.Texture = General.Map.Data.GetTextureImage(Sidedef.LongMiddleTexture);
					if(base.Texture == null)
					{
						base.Texture = General.Map.Data.MissingTexture3D;
						setuponloadedtexture = Sidedef.LongMiddleTexture;
					}
					else
					{
						if(!base.Texture.IsImageLoaded)
							setuponloadedtexture = Sidedef.LongMiddleTexture;
					}
				}
				else
				{
					// Use missing texture
					base.Texture = General.Map.Data.MissingTexture3D;
					setuponloadedtexture = 0;
				}

				// Get texture scaled size
				Vector2D tsz = new Vector2D(base.Texture.ScaledWidth, base.Texture.ScaledHeight);
				tsz = tsz * tscale;

				// Get texture offsets
				Vector2D tof = new Vector2D(Sidedef.OffsetX, Sidedef.OffsetY);
				tof = tof + toffset;
				if(General.Map.Config.ScaledTextureOffsets && !base.Texture.WorldPanning)
					tof = tof * base.Texture.Scale;
				
				// Determine texture coordinates plane as they would be in normal circumstances.
				// We can then use this plane to find any texture coordinate we need.
				// The logic here is the same as in the original VisualMiddleSingle (except that
				// the values are stored in a TexturePlane)
				// NOTE: I use a small bias for the floor height, because if the difference in
				// height is 0 then the TexturePlane doesn't work!
				TexturePlane tp = new TexturePlane();
				float floorbias = (Sidedef.Sector.CeilHeight == Sidedef.Sector.FloorHeight) ? 1.0f : 0.0f;
				if(Sidedef.Line.IsFlagSet(General.Map.Config.LowerUnpeggedFlag))
				{
					// When lower unpegged is set, the middle texture is bound to the bottom
					tp.tlt.y = tsz.y - (float)(Sidedef.Sector.CeilHeight - Sidedef.Sector.FloorHeight);
				}
				tp.trb.x = tp.tlt.x + Sidedef.Line.Length;
				tp.trb.y = tp.tlt.y + ((float)Sidedef.Sector.CeilHeight - ((float)Sidedef.Sector.FloorHeight + floorbias));
				
				// Apply texture offset
				tp.tlt += tof;
				tp.trb += tof;
				
				// Transform pixel coordinates to texture coordinates
				tp.tlt /= tsz;
				tp.trb /= tsz;
				
				// Left top and right bottom of the geometry that
				tp.vlt = new Vector3D(vl.x, vl.y, (float)Sidedef.Sector.CeilHeight);
				tp.vrb = new Vector3D(vr.x, vr.y, (float)Sidedef.Sector.FloorHeight + floorbias);
				
				// Make the right-top coordinates
				tp.trt = new Vector2D(tp.trb.x, tp.tlt.y);
				tp.vrt = new Vector3D(tp.vrb.x, tp.vrb.y, tp.vlt.z);
			
				// Keep top and bottom planes for intersection testing
				top = sd.Ceiling.plane;
				bottom = sd.Floor.plane;
				
				// Create initial polygon, which is just a quad between floor and ceiling
				WallPolygon poly = new WallPolygon();
				poly.Add(new Vector3D(vl.x, vl.y, sd.Floor.plane.GetZ(vl)));
				poly.Add(new Vector3D(vl.x, vl.y, sd.Ceiling.plane.GetZ(vl)));
				poly.Add(new Vector3D(vr.x, vr.y, sd.Ceiling.plane.GetZ(vr)));
				poly.Add(new Vector3D(vr.x, vr.y, sd.Floor.plane.GetZ(vr)));
				
				// Determine initial color
				int lightlevel = lightabsolute ? lightvalue : sd.Ceiling.brightnessbelow + lightvalue;
				PixelColor wallbrightness = PixelColor.FromInt(mode.CalculateBrightness(lightlevel));
				PixelColor wallcolor = PixelColor.Modulate(sd.Ceiling.colorbelow, wallbrightness);
				poly.color = wallcolor.WithAlpha(255).ToInt();
				
				// Cut off the part below the other floor and above the other ceiling
				CropPoly(ref poly, osd.Ceiling.plane, true);
				CropPoly(ref poly, osd.Floor.plane, true);
				
				// Determine if we should repeat the middle texture
				repeatmidtex = false;
				if(Sidedef.Fields.ContainsKey("wrapmidtex"))
				{
					if(Sidedef.Fields["wrapmidtex"].Value is bool)
						repeatmidtex = (bool)Sidedef.Fields["wrapmidtex"].Value;
				}
				else
					repeatmidtex = Sidedef.Line.IsFlagSet("wrapmidtex");
				
				if(!repeatmidtex)
				{
					// First determine the visible portion of the texture
					float geotop = (float)Math.Min(Sidedef.Sector.CeilHeight, Sidedef.Other.Sector.CeilHeight);
					float geobottom = (float)Math.Max(Sidedef.Sector.FloorHeight, Sidedef.Other.Sector.FloorHeight);
					float textop, texbottom;
					
					// Determine top portion height
					if(Sidedef.Line.IsFlagSet(General.Map.Config.LowerUnpeggedFlag))
						textop = geobottom + tsz.y;
					else
						textop = geotop;
					
					// Calculate bottom portion height
					texbottom = textop - tsz.y;
					
					// Create crop planes (we also need these for intersection testing)
					topclipplane = new Plane(new Vector3D(0, 0, -1), textop);
					bottomclipplane = new Plane(new Vector3D(0, 0, 1), -texbottom);
					
					// Crop polygon by these heights
					CropPoly(ref poly, topclipplane, true);
					CropPoly(ref poly, bottomclipplane, true);
				}
				
				if(poly.Count > 2)
				{
					// Keep top and bottom planes for intersection testing
					top = osd.Ceiling.plane;
					bottom = osd.Floor.plane;

					// Process the polygon and create vertices
					List<WorldVertex> verts = CreatePolygonVertices(poly, tp, sd, lightvalue, lightabsolute);
					if(verts.Count > 0)
					{
						// Apply alpha to vertices
						byte alpha = SetLinedefRenderstyle(true);
						if(alpha < 255)
						{
							for(int i = 0; i < verts.Count; i++)
							{
								WorldVertex v = verts[i];
								PixelColor c = PixelColor.FromInt(v.c);
								v.c = c.WithAlpha(alpha).ToInt();
								verts[i] = v;
							}
						}
						
						base.SetVertices(verts);
						return true;
					}
				}
			}
			
			return false;
		}
		
		#endregion

		#region ================== Methods

		// This performs a fast test in object picking
		public override bool PickFastReject(Vector3D from, Vector3D to, Vector3D dir)
		{
			if(!repeatmidtex)
			{
				// Whe nthe texture is not repeated, leave when outside crop planes
				if((pickintersect.z < bottomclipplane.GetZ(pickintersect)) ||
				   (pickintersect.z > topclipplane.GetZ(pickintersect)))
				   return false;
			}
			
			return base.PickFastReject(from, to, dir);
		}
		
		// Return texture name
		public override string GetTextureName()
		{
			return this.Sidedef.MiddleTexture;
		}

		// This changes the texture
		protected override void SetTexture(string texturename)
		{
			this.Sidedef.SetTextureMid(texturename);
			General.Map.Data.UpdateUsedTextures();
			this.Setup();
		}
		
		#endregion
	}
}