#region Copyright & License Information
/*
 * Copyright 2007,2009,2010 Chris Forbes, Robert Pepperell, Matthew Bowra-Dean, Paul Chote, Alli Witheford.
 * This file is part of OpenRA.
 * 
 *  OpenRA is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 * 
 *  OpenRA 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.
 * 
 *  You should have received a copy of the GNU General Public License
 *  along with OpenRA.  If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System.Collections.Generic;
using OpenRA.GameRules;
using OpenRA.Traits;
using System.Linq;

namespace OpenRA.Orders
{
	class PlaceBuildingOrderGenerator : IOrderGenerator
	{
		readonly Actor Producer;
		readonly string Building;
		BuildingInfo BuildingInfo { get { return Rules.Info[ Building ].Traits.Get<BuildingInfo>(); } }

		public PlaceBuildingOrderGenerator(Actor producer, string name)
		{
			Producer = producer;
			Building = name;
		}

		public IEnumerable<Order> Order(World world, int2 xy, MouseInput mi)
		{
			if (mi.Button == MouseButton.Right)
				Game.controller.CancelInputMode();

			return InnerOrder(world, xy, mi);
		}

		IEnumerable<Order> InnerOrder(World world, int2 xy, MouseInput mi)
		{
			if (mi.Button == MouseButton.Left)
			{
				var topLeft = xy - Footprint.AdjustForBuildingSize( BuildingInfo );
				if (!world.CanPlaceBuilding( Building, BuildingInfo, topLeft, null)
					|| !world.IsCloseEnoughToBase(Producer.Owner, Building, BuildingInfo, topLeft))
				{
					var eva = world.LocalPlayer.PlayerActor.Info.Traits.Get<EvaAlertsInfo>();
					Sound.Play(eva.BuildingCannotPlaceAudio);
					yield break;
				}
				
				yield return new Order("PlaceBuilding", Producer.Owner.PlayerActor, topLeft, Building);
				
				// Linebuild for walls.
				// Assumes a 1x1 footprint; weird things will happen for other footprints
				if (Rules.Info[ Building ].Traits.Contains<LineBuildInfo>())
				{
					int range = Rules.Info[ Building ].Traits.Get<LineBuildInfo>().Range;
				
					// Start at place location, search outwards
					// TODO: First make it work, then make it nice
					int[] dirs = {0,0,0,0};
					for (int d = 0; d < 4; d++)
					{
						for (int i = 1; i < range; i++)
						{
							if (dirs[d] != 0)
								continue;
							
							int2 cell = world.OffsetCell(topLeft,i,d);
							
							if (world.IsCellBuildable(cell, BuildingInfo.WaterBound ? UnitMovementType.Float : UnitMovementType.Wheel,null))
								continue; // Cell is empty; continue search

							// Cell contains an actor. Is it the type we want?
							if (world.Queries.WithTrait<LineBuild>().Any(a => (a.Actor.Info.Name == Building && a.Actor.Location.X == cell.X && a.Actor.Location.Y == cell.Y)))
								dirs[d] = i; // Cell contains actor of correct type
							else
								dirs[d] = -1; // Cell is blocked by another actor type
						}
						
						// Place intermediate-line sections
						if (dirs[d] > 0)
							for (int i = 1; i < dirs[d]; i++)
								yield return new Order("PlaceBuilding", Producer.Owner.PlayerActor, world.OffsetCell(topLeft,i,d), Building);
					}
				}
			}
		}
		
		public void Tick( World world )
		{
			var producing = Producer.traits.Get<Traits.ProductionQueue>().CurrentItem( Rules.Info[ Building ].Category );
			if (producing == null || producing.Item != Building || producing.RemainingTime != 0)
				Game.controller.CancelInputMode();
		}

		public void Render( World world )
		{
			world.WorldRenderer.uiOverlay.DrawBuildingGrid( world, Building, BuildingInfo );
		}

		public string GetCursor(World world, int2 xy, MouseInput mi) { return "default"; }
	}
}