using System;

using System.Collections.Generic;

using System.Linq;

namespace Assistance {

	public class Workarea {

		public readonly Document document;

		public readonly InputManager inputManager;

		private readonly InputModifierTangents modifierTangents;

		private readonly InputModifierAssistants modifierAssistants;

		private readonly InputModifierSegmentation modifierSegmentation;

		public Workarea() {

			document = new Document(this);

			inputManager = new InputManager(this);

			modifierTangents = new InputModifierTangents();

			modifierAssistants = new InputModifierAssistants(this);

			modifierSegmentation = new InputModifierSegmentation();

		}

		public Tool getTool()

			{ return inputManager.getTool(); }

		public void setTool(Tool tool, bool force = false) {

			if (getTool() != tool || force) {

				inputManager.deactivate();

				inputManager.clearModifiers();

				if (tool != null) {

					Tool.ModifierTypes types = tool.getAvailableModifierTypes();

					if ((Tool.ModifierTypes.Tangents & types) != 0)

						inputManager.addModifier(modifierTangents);

					if ((Tool.ModifierTypes.Guideline & types) != 0)

						inputManager.addModifier(modifierAssistants);

					if ((Tool.ModifierTypes.Multiline & types) != 0)

						foreach(Modifier modifier in document.modifiers)

							inputManager.addModifier(modifier);

					if ((Tool.ModifierTypes.Segmentation & types) != 0)

						inputManager.addModifier(modifierSegmentation);

				}

				inputManager.setTool(tool);

				inputManager.activate();

			}

		}

		public void updateModifiers()

			{ setTool(getTool(), true); }

		public ActivePoint findPoint(Point position) {

			foreach(ActivePoint point in document.points.Reverse<ActivePoint>())

				if (point.isInside(position))

					return point;

			return null;

		}

		public void getGuidelines(List<Guideline> outGuidelines, Point target) {

			foreach(Assistant assistant in document.assistants)

				assistant.getGuidelines(outGuidelines, target);

		}

		public void draw(Cairo.Context context, List<Point> hovers, ActivePoint activePoint) {

			// canvas

			document.canvas.draw(context);

			// input manager

			inputManager.draw(context, hovers);

			// modifiers

			foreach(Modifier modifier in document.modifiers)

				modifier.draw(context);

			// assistants

			foreach(Assistant assistant in document.assistants)

				assistant.draw(context);

			// active points

			foreach(ActivePoint point in document.points)

				point.draw(context, activePoint == point);

		}

	}

}