#region Copyright & License Information
/*
 * Copyright 2007-2014 The OpenRA Developers (see AUTHORS)
 * This file is part of OpenRA, which is free software. It is made
 * available to you under the terms of the GNU General Public License
 * as published by the Free Software Foundation. For more information,
 * see COPYING.
 */
#endregion

using System;
using System.Linq;

namespace OpenRA.Mods.RA.AI
{
	class BaseBuilder
	{
		enum BuildState	{ ChooseItem, WaitForProduction, WaitForFeedback }

		BuildState state = BuildState.WaitForFeedback;
		string category;
		HackyAI ai;
		int lastThinkTick;
		Func<ProductionQueue, ActorInfo> chooseItem;

		public BaseBuilder(HackyAI ai, string category, Func<ProductionQueue, ActorInfo> chooseItem)
		{
			this.ai = ai;
			this.category = category;
			this.chooseItem = chooseItem;
		}

		public void Tick()
		{
			// Pick a free queue
			var queue = ai.FindQueues(category).FirstOrDefault();
			if (queue == null)
				return;

			var currentBuilding = queue.CurrentItem();
			switch (state)
			{
			case BuildState.ChooseItem:
				var item = chooseItem(queue);
				if (item == null)
				{
					state = BuildState.WaitForFeedback;
					lastThinkTick = ai.ticks;
				}
				else
				{
					HackyAI.BotDebug("AI: Starting production of {0}".F(item.Name));
					state = BuildState.WaitForProduction;
					ai.world.IssueOrder(Order.StartProduction(queue.Actor, item.Name, 1));
				}
				break;

			case BuildState.WaitForProduction:
				if (currentBuilding == null)
					return;

				if (currentBuilding.Paused)
					ai.world.IssueOrder(Order.PauseProduction(queue.Actor, currentBuilding.Item, false));
				else if (currentBuilding.Done)
				{
					state = BuildState.WaitForFeedback;
					lastThinkTick = ai.ticks;

					// Place the building
					var type = BuildingType.Building;
					if (ai.Map.Rules.Actors[currentBuilding.Item].Traits.Contains<AttackBaseInfo>())
						type = BuildingType.Defense;
					else if (ai.Map.Rules.Actors[currentBuilding.Item].Traits.Contains<OreRefineryInfo>())
						type = BuildingType.Refinery;

					var location = ai.ChooseBuildLocation(currentBuilding.Item, type);
					if (location == null)
					{
						HackyAI.BotDebug("AI: Nowhere to place {0}".F(currentBuilding.Item));
						ai.world.IssueOrder(Order.CancelProduction(queue.Actor, currentBuilding.Item, 1));
					}
					else
					{
						ai.world.IssueOrder(new Order("PlaceBuilding", ai.p.PlayerActor, false)
						{
							TargetLocation = location.Value,
							TargetString = currentBuilding.Item,
							SuppressVisualFeedback = true
						});
					}
				}

				break;

			case BuildState.WaitForFeedback:
				if (ai.ticks - lastThinkTick > HackyAI.feedbackTime)
					state = BuildState.ChooseItem;
				break;
			}
		}
	}
}