/**
 *                        WHITEBOPHIR
 *********************************************************
 * @licstart  The following is the entire license notice for the 
 *  JavaScript code in this page.
 *
 * Copyright (C) 2013  Ophir LOJKINE
 *
 *
 * The JavaScript code in this page is free software: you can
 * redistribute it and/or modify it under the terms of the GNU
 * General Public License (GNU GPL) as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option)
 * any later version.  The code is distributed WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU GPL for more details.
 *
 * As additional permission under GNU GPL version 3 section 7, you
 * may distribute non-source (e.g., minimized or compacted) forms of
 * that code without the copy of the GNU GPL normally required by
 * section 4, provided you include this license notice and a URL
 * through which recipients can access the Corresponding Source.
 *
 * @licend
 */

(function () { //Code isolation
	//Indicates the id of the line the user is currently drawing or an empty string while the user is not drawing
	var curLineId = "",
		curUpdate = { //The data of the message that will be sent for every new point
			'type': 'update',
			'id': "",
			'x2': 0,
			'y2': 0
		},
		lastTime = performance.now(); //The time at which the last point was drawn

	function startLine(x, y, evt) {

		//Prevent the press from being interpreted by the browser
		evt.preventDefault();

		curLineId = Tools.generateUID("s"); //"s" for straight line

		Tools.drawAndSend({
			'type': 'straight',
			'id': curLineId,
			'color': Tools.getColor(),
			'size': Tools.getSize(),
			'x': x,
			'y': y
		});

		curUpdate.id = curLineId;
	}

	function continueLine(x, y, evt) {
		/*Wait 70ms before adding any point to the currently drawing line.
		This allows the animation to be smother*/
		if (curLineId !== "") {
			curUpdate['x2'] = x; curUpdate['y2'] = y;
			if (performance.now() - lastTime > 70) {
				Tools.drawAndSend(curUpdate);
				lastTime = performance.now();
			} else {
				draw(curUpdate);
			}
		}
		if (evt) evt.preventDefault();
	}

	function stopLine(x, y) {
		//Add a last point to the line
		continueLine(x, y);
		curLineId = "";
	}

	function draw(data) {
		switch (data.type) {
			case "straight":
				createLine(data);
				break;
			case "update":
				var line = svg.getElementById(data['id']);
				if (!line) {
					console.error("Straight line: Hmmm... I received a point of a line that has not been created (%s).", data['id']);
					createLine({ //create a new line in order not to loose the points
						"id": data['id'],
						"x": data['x2'],
						"y": data['y2']
					});
				}
				updateLine(line, data);
				break;
			default:
				console.error("Straight Line: Draw instruction with unknown type. ", data);
				break;
		}
	}

	var svg = Tools.svg;
	function createLine(lineData) {
		//Creates a new line on the canvas, or update a line that already exists with new information
		var line = svg.getElementById(lineData.id) || Tools.createSVGElement("line");
		line.id = lineData.id;
		line.x1.baseVal.value = lineData['x'];
		line.y1.baseVal.value = lineData['y'];
		line.x2.baseVal.value = lineData['x2'] || lineData['x'];
		line.y2.baseVal.value = lineData['y2'] || lineData['y'];
		//If some data is not provided, choose default value. The line may be updated later
		line.setAttribute("stroke", lineData.color || "black");
		line.setAttribute("stroke-width", lineData.size || 10);
		svg.appendChild(line);
		return line;
	}

	function updateLine(line, data) {
		line.x2.baseVal.value = data['x2'];
		line.y2.baseVal.value = data['y2'];
	}

	Tools.add({ //The new tool
		"name": "Straight line",
		"icon": "☇",
		"listeners": {
			"press": startLine,
			"move": continueLine,
			"release": stopLine,
		},
		"draw": draw,
		"mouseCursor": "crosshair",
		"stylesheet": "tools/line/line.css"
	});

})(); //End of code isolation