svgedit/editor/svgutils.js

/*globals $, svgedit, unescape, DOMParser, ActiveXObject, getStrokedBBox*/
/*jslint vars: true, eqeq: true, bitwise: true, continue: true, forin: true*/
/**
 * Package: svgedit.utilities
 *
 * Licensed under the MIT License
 *
 * Copyright(c) 2010 Alexis Deveria
 * Copyright(c) 2010 Jeff Schiller
 */

// Dependencies:
// 1) jQuery
// 2) pathseg.js
// 3) browser.js
// 4) svgtransformlist.js
// 5) units.js

(function(undef) {'use strict';

if (!svgedit.utilities) {
	svgedit.utilities = {};
}

// Constants

// String used to encode base64.
var KEYSTR = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=';
var NS = svgedit.NS;

// Much faster than running getBBox() every time
var visElems = 'a,circle,ellipse,foreignObject,g,image,line,path,polygon,polyline,rect,svg,text,tspan,use';
var visElems_arr = visElems.split(',');
//var hidElems = 'clipPath,defs,desc,feGaussianBlur,filter,linearGradient,marker,mask,metadata,pattern,radialGradient,stop,switch,symbol,title,textPath';

var editorContext_ = null;
var domdoc_ = null;
var domcontainer_ = null;
var svgroot_ = null;

svgedit.utilities.init = function(editorContext) {
	editorContext_ = editorContext;
	domdoc_ = editorContext.getDOMDocument();
	domcontainer_ = editorContext.getDOMContainer();
	svgroot_ = editorContext.getSVGRoot();
};

// Function: svgedit.utilities.toXml
// Converts characters in a string to XML-friendly entities.
//
// Example: '&' becomes '&'
//
// Parameters:
// str - The string to be converted
//
// Returns:
// The converted string
svgedit.utilities.toXml = function(str) {
	// ' is ok in XML, but not HTML
	// > does not normally need escaping, though it can if within a CDATA expression (and preceded by "]]")
	return str.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;').replace(/'/, '&#x27;');
};

// Function: svgedit.utilities.fromXml
// Converts XML entities in a string to single characters.
// Example: '&amp;' becomes '&'
//
// Parameters:
// str - The string to be converted
//
// Returns:
// The converted string
svgedit.utilities.fromXml = function(str) {
	return $('<p/>').html(str).text();
};

// This code was written by Tyler Akins and has been placed in the
// public domain.  It would be nice if you left this header intact.
// Base64 code from Tyler Akins -- http://rumkin.com

// schiller: Removed string concatenation in favour of Array.join() optimization,
//				also precalculate the size of the array needed.

// Function: svgedit.utilities.encode64
// Converts a string to base64
svgedit.utilities.encode64 = function(input) {
	// base64 strings are 4/3 larger than the original string
	input = svgedit.utilities.encodeUTF8(input); // convert non-ASCII characters
	// input = svgedit.utilities.convertToXMLReferences(input);
	if (window.btoa) {
		return window.btoa(input); // Use native if available
    }
    var output = [];
	output.length = Math.floor( (input.length + 2) / 3 ) * 4;
	var chr1, chr2, chr3;
	var enc1, enc2, enc3, enc4;
	var i = 0, p = 0;

	do {
		chr1 = input.charCodeAt(i++);
		chr2 = input.charCodeAt(i++);
		chr3 = input.charCodeAt(i++);

		enc1 = chr1 >> 2;
		enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
		enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
		enc4 = chr3 & 63;

		if (isNaN(chr2)) {
			enc3 = enc4 = 64;
		} else if (isNaN(chr3)) {
			enc4 = 64;
		}

		output[p++] = KEYSTR.charAt(enc1);
		output[p++] = KEYSTR.charAt(enc2);
		output[p++] = KEYSTR.charAt(enc3);
		output[p++] = KEYSTR.charAt(enc4);
	} while (i < input.length);

	return output.join('');
};

// Function: svgedit.utilities.decode64
// Converts a string from base64
svgedit.utilities.decode64 = function(input) {
	if(window.atob) {
        return svgedit.utilities.decodeUTF8(window.atob(input));
    }
	var output = '';
	var chr1, chr2, chr3 = '';
	var enc1, enc2, enc3, enc4 = '';
	var i = 0;

	// remove all characters that are not A-Z, a-z, 0-9, +, /, or =
	input = input.replace(/[^A-Za-z0-9\+\/\=]/g, '');

	do {
		enc1 = KEYSTR.indexOf(input.charAt(i++));
		enc2 = KEYSTR.indexOf(input.charAt(i++));
		enc3 = KEYSTR.indexOf(input.charAt(i++));
		enc4 = KEYSTR.indexOf(input.charAt(i++));

		chr1 = (enc1 << 2) | (enc2 >> 4);
		chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
		chr3 = ((enc3 & 3) << 6) | enc4;

		output = output + String.fromCharCode(chr1);

		if (enc3 != 64) {
			output = output + String.fromCharCode(chr2);
		}
		if (enc4 != 64) {
			output = output + String.fromCharCode(chr3);
		}

		chr1 = chr2 = chr3 = '';
		enc1 = enc2 = enc3 = enc4 = '';

	} while (i < input.length);
    return svgedit.utilities.decodeUTF8(output);
};

svgedit.utilities.decodeUTF8 = function (argString) {
    return decodeURIComponent(escape(argString));
};

// codedread:does not seem to work with webkit-based browsers on OSX // Brettz9: please test again as function upgraded
svgedit.utilities.encodeUTF8 = function (argString) {
  return unescape(encodeURIComponent(argString));
};

// Function: svgedit.utilities.convertToXMLReferences
// Converts a string to use XML references
svgedit.utilities.convertToXMLReferences = function(input) {
	var n,
		output = '';
	for (n = 0; n < input.length; n++){
		var c = input.charCodeAt(n);
		if (c < 128) {
			output += input[n];
		} else if(c > 127) {
			output += ('&#' + c + ';');
		}
	}
	return output;
};

// Function: svgedit.utilities.text2xml
// Cross-browser compatible method of converting a string to an XML tree
// found this function here: http://groups.google.com/group/jquery-dev/browse_thread/thread/c6d11387c580a77f
svgedit.utilities.text2xml = function(sXML) {
	if(sXML.indexOf('<svg:svg') >= 0) {
		sXML = sXML.replace(/<(\/?)svg:/g, '<$1').replace('xmlns:svg', 'xmlns');
	}

	var out, dXML;
	try{
		dXML = (window.DOMParser)?new DOMParser():new ActiveXObject('Microsoft.XMLDOM');
		dXML.async = false;
	} catch(e){
		throw new Error('XML Parser could not be instantiated');
	}
	try{
		if (dXML.loadXML) {
			out = (dXML.loadXML(sXML)) ? dXML : false;
		}
		else {
			out = dXML.parseFromString(sXML, 'text/xml');
		}
	}
	catch(e2){ throw new Error('Error parsing XML string'); }
	return out;
};

// Function: svgedit.utilities.bboxToObj
// Converts a SVGRect into an object.
// 
// Parameters:
// bbox - a SVGRect
// 
// Returns:
// An object with properties names x, y, width, height.
svgedit.utilities.bboxToObj = function(bbox) {
	return {
		x: bbox.x,
		y: bbox.y,
		width: bbox.width,
		height: bbox.height
	};
};

// Function: svgedit.utilities.walkTree
// Walks the tree and executes the callback on each element in a top-down fashion
//
// Parameters:
// elem - DOM element to traverse
// cbFn - Callback function to run on each element
svgedit.utilities.walkTree = function(elem, cbFn){
	if (elem && elem.nodeType == 1) {
		cbFn(elem);
		var i = elem.childNodes.length;
		while (i--) {
			svgedit.utilities.walkTree(elem.childNodes.item(i), cbFn);
		}
	}
};

// Function: svgedit.utilities.walkTreePost
// Walks the tree and executes the callback on each element in a depth-first fashion
// TODO: FIXME: Shouldn't this be calling walkTreePost?
//
// Parameters:
// elem - DOM element to traverse
// cbFn - Callback function to run on each element
svgedit.utilities.walkTreePost = function(elem, cbFn) {
	if (elem && elem.nodeType == 1) {
		var i = elem.childNodes.length;
		while (i--) {
			svgedit.utilities.walkTree(elem.childNodes.item(i), cbFn);
		}
		cbFn(elem);
	}
};

// Function: svgedit.utilities.getUrlFromAttr
// Extracts the URL from the url(...) syntax of some attributes.
// Three variants:
//  * <circle fill="url(someFile.svg#foo)" />
//  * <circle fill="url('someFile.svg#foo')" />
//  * <circle fill='url("someFile.svg#foo")' />
//
// Parameters:
// attrVal - The attribute value as a string
//
// Returns:
// String with just the URL, like someFile.svg#foo
svgedit.utilities.getUrlFromAttr = function(attrVal) {
	if (attrVal) {
		// url("#somegrad")
		if (attrVal.indexOf('url("') === 0) {
			return attrVal.substring(5, attrVal.indexOf('"',6));
		}
		// url('#somegrad')
		if (attrVal.indexOf("url('") === 0) {
			return attrVal.substring(5, attrVal.indexOf("'",6));
		}
		if (attrVal.indexOf("url(") === 0) {
			return attrVal.substring(4, attrVal.indexOf(')'));
		}
	}
	return null;
};

// Function: svgedit.utilities.getHref
// Returns the given element's xlink:href value
svgedit.utilities.getHref = function(elem) {
	return elem.getAttributeNS(NS.XLINK, 'href');
};

// Function: svgedit.utilities.setHref
// Sets the given element's xlink:href value
svgedit.utilities.setHref = function(elem, val) {
	elem.setAttributeNS(NS.XLINK, 'xlink:href', val);
};

// Function: findDefs
//
// Returns:
// The document's <defs> element, create it first if necessary
svgedit.utilities.findDefs = function() {
	var svgElement = editorContext_.getSVGContent();
	var defs = svgElement.getElementsByTagNameNS(NS.SVG, 'defs');
	if (defs.length > 0) {
		defs = defs[0];
	} else {
		defs = svgElement.ownerDocument.createElementNS(NS.SVG, 'defs');
		if (svgElement.firstChild) {
			// first child is a comment, so call nextSibling
			svgElement.insertBefore(defs, svgElement.firstChild.nextSibling);
		} else {
			svgElement.appendChild(defs);
		}
	}
	return defs;
};

// TODO(codedread): Consider moving the next to functions to bbox.js

// Function: svgedit.utilities.getPathBBox
// Get correct BBox for a path in Webkit
// Converted from code found here:
// http://blog.hackers-cafe.net/2009/06/how-to-calculate-bezier-curves-bounding.html
//
// Parameters:
// path - The path DOM element to get the BBox for
//
// Returns:
// A BBox-like object
svgedit.utilities.getPathBBox = function(path) {
	var seglist = path.pathSegList;
	var tot = seglist.numberOfItems;

	var bounds = [[], []];
	var start = seglist.getItem(0);
	var P0 = [start.x, start.y];

	var i;
	for (i = 0; i < tot; i++) {
		var seg = seglist.getItem(i);

		if(seg.x === undef) {continue;}

		// Add actual points to limits
		bounds[0].push(P0[0]);
		bounds[1].push(P0[1]);

		if (seg.x1) {
			var P1 = [seg.x1, seg.y1],
				P2 = [seg.x2, seg.y2],
				P3 = [seg.x, seg.y];

			var j;
			for (j = 0; j < 2; j++) {

				var calc = function(t) {
					return Math.pow(1-t,3) * P0[j]
						+ 3 * Math.pow(1-t,2) * t * P1[j]
						+ 3 * (1-t) * Math.pow(t, 2) * P2[j]
						+ Math.pow(t,3) * P3[j];
				};

				var b = 6 * P0[j] - 12 * P1[j] + 6 * P2[j];
				var a = -3 * P0[j] + 9 * P1[j] - 9 * P2[j] + 3 * P3[j];
				var c = 3 * P1[j] - 3 * P0[j];

				if (a == 0) {
					if (b == 0) {
						continue;
					}
					var t = -c / b;
					if (0 < t && t < 1) {
						bounds[j].push(calc(t));
					}
					continue;
				}
				var b2ac = Math.pow(b,2) - 4 * c * a;
				if (b2ac < 0) {continue;}
				var t1 = (-b + Math.sqrt(b2ac))/(2 * a);
				if (0 < t1 && t1 < 1) {bounds[j].push(calc(t1));}
				var t2 = (-b - Math.sqrt(b2ac))/(2 * a);
				if (0 < t2 && t2 < 1) {bounds[j].push(calc(t2));}
			}
			P0 = P3;
		} else {
			bounds[0].push(seg.x);
			bounds[1].push(seg.y);
		}
	}

	var x = Math.min.apply(null, bounds[0]);
	var w = Math.max.apply(null, bounds[0]) - x;
	var y = Math.min.apply(null, bounds[1]);
	var h = Math.max.apply(null, bounds[1]) - y;
	return {
		'x': x,
		'y': y,
		'width': w,
		'height': h
	};
};

// Function: groupBBFix
// Get the given/selected element's bounding box object, checking for
// horizontal/vertical lines (see issue 717)
// Note that performance is currently terrible, so some way to improve would
// be great.
//
// Parameters:
// selected - Container or <use> DOM element
function groupBBFix(selected) {
	if(svgedit.browser.supportsHVLineContainerBBox()) {
		try { return selected.getBBox();} catch(e){}
	}
	var ref = $.data(selected, 'ref');
	var matched = null;
	var ret, copy;

	if(ref) {
		copy = $(ref).children().clone().attr('visibility', 'hidden');
		$(svgroot_).append(copy);
		matched = copy.filter('line, path');
	} else {
		matched = $(selected).find('line, path');
	}

	var issue = false;
	if(matched.length) {
		matched.each(function() {
			var bb = this.getBBox();
			if(!bb.width || !bb.height) {
				issue = true;
			}
		});
		if(issue) {
			var elems = ref ? copy : $(selected).children();
			ret = getStrokedBBox(elems); // getStrokedBBox defined in svgcanvas
		} else {
			ret = selected.getBBox();
		}
	} else {
		ret = selected.getBBox();
	}
	if(ref) {
		copy.remove();
	}
	return ret;
}

// Function: svgedit.utilities.getBBox
// Get the given/selected element's bounding box object, convert it to be more
// usable when necessary
//
// Parameters:
// elem - Optional DOM element to get the BBox for
svgedit.utilities.getBBox = function(elem) {
	var selected = elem || editorContext_.geSelectedElements()[0];
	if (elem.nodeType != 1) {return null;}
	var ret = null;
	var elname = selected.nodeName;

	switch ( elname ) {
	case 'text':
		if(selected.textContent === '') {
			selected.textContent = 'a'; // Some character needed for the selector to use.
			ret = selected.getBBox();
			selected.textContent = '';
		} else {
			if (selected.getBBox) { ret = selected.getBBox(); }
		}
		break;
	case 'path':
		if(!svgedit.browser.supportsPathBBox()) {
			ret = svgedit.utilities.getPathBBox(selected);
		} else {
			if (selected.getBBox) { ret = selected.getBBox(); }
		}
		break;
	case 'g':
	case 'a':
		ret = groupBBFix(selected);
		break;
	default:

		if(elname === 'use') {
			ret = groupBBFix(selected, true);
		}
		if(elname === 'use' || ( elname === 'foreignObject' && svgedit.browser.isWebkit() ) ) {
			if(!ret) {ret = selected.getBBox();}
			// This is resolved in later versions of webkit, perhaps we should
			// have a featured detection for correct 'use' behavior?
			// ——————————
			if(!svgedit.browser.isWebkit()) {
				var bb = {};
				bb.width = ret.width;
				bb.height = ret.height;
				bb.x = ret.x + parseFloat(selected.getAttribute('x')||0);
				bb.y = ret.y + parseFloat(selected.getAttribute('y')||0);
				ret = bb;
			}
		} else if(~visElems_arr.indexOf(elname)) {
			if (selected) { ret = selected.getBBox(); }
			else {
				// Check if element is child of a foreignObject
				var fo = $(selected).closest('foreignObject');
				if (fo.length) {
					if (fo[0].getBBox) {
						ret = fo[0].getBBox();
					}
				}
			}
		}
	}
	if(ret) {
		ret = svgedit.utilities.bboxToObj(ret);
	}

	// get the bounding box from the DOM (which is in that element's coordinate system)
	return ret;
};

// Function: getPathDFromSegments
// Create a path 'd' attribute from path segments.
// Each segment is an array of the form: [singleChar, [x,y, x,y, ...]]
//
// Parameters:
// pathSegments - An array of path segments to be converted
//
// Returns:
// The converted path d attribute.
svgedit.utilities.getPathDFromSegments = function(pathSegments) {
	var d = '';

	$.each(pathSegments, function(j, seg) {
		var i;
		var pts = seg[1];
		d += seg[0];
		for (i = 0; i < pts.length; i+=2) {
			d += (pts[i] +','+pts[i+1]) + ' ';
		}
	});

	return d;
};

// Function: getPathDFromElement
// Make a path 'd' attribute from a simple SVG element shape.
//
// Parameters:
// elem - The element to be converted
//
// Returns:
// The path d attribute or undefined if the element type is unknown.
svgedit.utilities.getPathDFromElement = function(elem) {

	// Possibly the cubed root of 6, but 1.81 works best
	var num = 1.81;
	var d, a, rx, ry;
	switch (elem.tagName) {
		case 'ellipse':
		case 'circle':
			a = $(elem).attr(['rx', 'ry', 'cx', 'cy']);
			var cx = a.cx, cy = a.cy;
			rx = a.rx;
			ry = a.ry;
			if (elem.tagName == 'circle') {
				rx = ry = $(elem).attr('r');
			}

			d = svgedit.utilities.getPathDFromSegments([
				['M',[(cx-rx),(cy)]],
				['C',[(cx-rx),(cy-ry/num), (cx-rx/num),(cy-ry), (cx),(cy-ry)]],
				['C',[(cx+rx/num),(cy-ry), (cx+rx),(cy-ry/num), (cx+rx),(cy)]],
				['C',[(cx+rx),(cy+ry/num), (cx+rx/num),(cy+ry), (cx),(cy+ry)]],
				['C',[(cx-rx/num),(cy+ry), (cx-rx),(cy+ry/num), (cx-rx),(cy)]],
				['Z',[]]
			]);
			break;
		case 'path':
			d = elem.getAttribute('d');
			break;
		case 'line':
			a = $(elem).attr(['x1', 'y1', 'x2', 'y2']);
			d = 'M'+a.x1+','+a.y1+'L'+a.x2+','+a.y2;
			break;
		case 'polyline':
			d = 'M' + elem.getAttribute('points');
			break;
		case 'polygon':
			d = 'M' + elem.getAttribute('points') + ' Z';
			break;
		case 'rect':
			var r = $(elem).attr(['rx', 'ry']);
			rx = r.rx;
			ry = r.ry;
			var b = elem.getBBox();
			var x = b.x, y = b.y, w = b.width, h = b.height;
			num = 4 - num; // Why? Because!

			if (!rx && !ry) {
				// Regular rect
				d = svgedit.utilities.getPathDFromSegments([
					['M',[x, y]],
					['L',[x+w, y]],
					['L',[x+w, y+h]],
					['L',[x, y+h]],
					['L',[x, y]],
					['Z',[]]
				]);
			} else {
				d = svgedit.utilities.getPathDFromSegments([
					['M',[x, y+ry]],
					['C',[x, y+ry/num, x+rx/num, y, x+rx, y]],
					['L',[x+w-rx, y]],
					['C',[x+w-rx/num, y, x+w, y+ry/num, x+w, y+ry]],
					['L',[x+w, y+h-ry]],
					['C',[x+w, y+h-ry/num, x+w-rx/num, y+h, x+w-rx, y+h]],
					['L',[x+rx, y+h]],
					['C',[x+rx/num, y+h, x, y+h-ry/num, x, y+h-ry]],
					['L',[x, y+ry]],
					['Z',[]]
				]);
			}
			break;
		default:
			break;
	}

	return d;

};

// Function: getExtraAttributesForConvertToPath
// Get a set of attributes from an element that is useful for convertToPath.
//
// Parameters:
// elem - The element to be probed
//
// Returns:
// An object with attributes.
svgedit.utilities.getExtraAttributesForConvertToPath = function(elem) {
	var attrs = {} ;
	// TODO: make this list global so that we can properly maintain it
	// TODO: what about @transform, @clip-rule, @fill-rule, etc?
	$.each(['marker-start', 'marker-end', 'marker-mid', 'filter', 'clip-path'], function() {
		var a = elem.getAttribute(this);
		if (a) {
			attrs[this] = a;
		}
	});
	return attrs;
};

// Function: getBBoxOfElementAsPath
// Get the BBox of an element-as-path
//
// Parameters:
// elem - The DOM element to be probed
// addSvgElementFromJson - Function to add the path element to the current layer. See canvas.addSvgElementFromJson
// pathActions - If a transform exists, pathActions.resetOrientation() is used. See: canvas.pathActions.
//
// Returns:
// The resulting path's bounding box object.
svgedit.utilities.getBBoxOfElementAsPath = function(elem, addSvgElementFromJson, pathActions) {

	var path = addSvgElementFromJson({
		'element': 'path',
		'attr': svgedit.utilities.getExtraAttributesForConvertToPath(elem)
	});

	var eltrans = elem.getAttribute('transform');
	if (eltrans) {
		path.setAttribute('transform', eltrans);
	}

	var parent = elem.parentNode;
	if (elem.nextSibling) {
		parent.insertBefore(path, elem);
	} else {
		parent.appendChild(path);
	}

	var d = svgedit.utilities.getPathDFromElement(elem);
	if (d)
		path.setAttribute('d', d);
	else
		path.parentNode.removeChild(path);

	// Get the correct BBox of the new path, then discard it
	pathActions.resetOrientation(path);
	var bb = false;
	try {
		bb = path.getBBox();
	} catch(e) {
		// Firefox fails
	}
	path.parentNode.removeChild(path);
	return bb;
};

// Function: convertToPath
// Convert selected element to a path.
//
// Parameters:
// elem - The DOM element to be converted
// attrs - Apply attributes to new path. see canvas.convertToPath
// addSvgElementFromJson - Function to add the path element to the current layer. See canvas.addSvgElementFromJson
// pathActions - If a transform exists, pathActions.resetOrientation() is used. See: canvas.pathActions.
// clearSelection - see canvas.clearSelection
// addToSelection - see canvas.addToSelection
// history - see svgedit.history
// addCommandToHistory - see canvas.addCommandToHistory
//
// Returns:
// The converted path element or null if the DOM element was not recognized.
svgedit.utilities.convertToPath = function(elem, attrs, addSvgElementFromJson, pathActions, clearSelection, addToSelection, history, addCommandToHistory) {

	var batchCmd = new history.BatchCommand('Convert element to Path');

	// Any attribute on the element not covered by the passed-in attributes
	attrs = $.extend({}, attrs, svgedit.utilities.getExtraAttributesForConvertToPath(elem));

	var path = addSvgElementFromJson({
		'element': 'path',
		'attr': attrs
	});

	var eltrans = elem.getAttribute('transform');
	if (eltrans) {
		path.setAttribute('transform', eltrans);
	}

	var id = elem.id;
	var parent = elem.parentNode;
	if (elem.nextSibling) {
		parent.insertBefore(path, elem);
	} else {
		parent.appendChild(path);
	}

	var d = svgedit.utilities.getPathDFromElement(elem);
	if (d) {
		path.setAttribute('d', d);

		// Replace the current element with the converted one

		// Reorient if it has a matrix
		if (eltrans) {
			var tlist = svgedit.transformlist.getTransformList(path);
			if (svgedit.math.hasMatrixTransform(tlist)) {
				pathActions.resetOrientation(path);
			}
		}

		var nextSibling = elem.nextSibling;
		batchCmd.addSubCommand(new history.RemoveElementCommand(elem, nextSibling, parent));
		batchCmd.addSubCommand(new history.InsertElementCommand(path));

		clearSelection();
		elem.parentNode.removeChild(elem);
		path.setAttribute('id', id);
		path.removeAttribute('visibility');
		addToSelection([path], true);

		addCommandToHistory(batchCmd);

		return path;
	} else {
		// the elem.tagName was not recognized, so no "d" attribute. Remove it, so we've haven't changed anything.
		path.parentNode.removeChild(path);
		return null;
	}

};

// Function: bBoxCanBeOptimizedOverNativeGetBBox
// Can the bbox be optimized over the native getBBox? The optimized bbox is the same as the native getBBox when
// the rotation angle is a multiple of 90 degrees and there are no complex transforms.
// Getting an optimized bbox can be dramatically slower, so we want to make sure it's worth it.
//
// The best example for this is a circle rotate 45 degrees. The circle doesn't get wider or taller when rotated
// about it's center.
//
// The standard, unoptimized technique gets the native bbox of the circle, rotates the box 45 degrees, uses
// that width and height, and applies any transforms to get the final bbox. This means the calculated bbox
// is much wider than the original circle. If the angle had been 0, 90, 180, etc. both techniques render the
// same bbox.
//
// The optimization is not needed if the rotation is a multiple 90 degrees. The default technique is to call
// getBBox then apply the angle and any transforms.
//
// Parameters:
// angle - The rotation angle in degrees
// hasMatrixTransform - True if there is a matrix transform
//
// Returns:
// True if the bbox can be optimized.
function bBoxCanBeOptimizedOverNativeGetBBox(angle, hasMatrixTransform) {
	var angleModulo90 = angle % 90;
	var closeTo90 = angleModulo90 < -89.99 || angleModulo90 > 89.99;
	var closeTo0 = angleModulo90 > -0.001 && angleModulo90 < 0.001;
	return hasMatrixTransform || ! (closeTo0 || closeTo90);
}

// Function: getBBoxWithTransform
// Get bounding box that includes any transforms.
//
// Parameters:
// elem - The DOM element to be converted
// addSvgElementFromJson - Function to add the path element to the current layer. See canvas.addSvgElementFromJson
// pathActions - If a transform exists, pathActions.resetOrientation() is used. See: canvas.pathActions.
//
// Returns:
// A single bounding box object
svgedit.utilities.getBBoxWithTransform = function(elem, addSvgElementFromJson, pathActions) {
	// TODO: Fix issue with rotated groups. Currently they work
	// fine in FF, but not in other browsers (same problem mentioned
	// in Issue 339 comment #2).

	var bb = svgedit.utilities.getBBox(elem);

	if (!bb) {
		return null;
	}

	var tlist = svgedit.transformlist.getTransformList(elem);
	var angle = svgedit.utilities.getRotationAngleFromTransformList(tlist);
	var hasMatrixTransform = svgedit.math.hasMatrixTransform(tlist);

	if (angle || hasMatrixTransform) {

		var good_bb = false;
		if (bBoxCanBeOptimizedOverNativeGetBBox(angle, hasMatrixTransform)) {
			// Get the BBox from the raw path for these elements
			// TODO: why ellipse and not circle
			var elemNames = ['ellipse', 'path', 'line', 'polyline', 'polygon'];
			if (elemNames.indexOf(elem.tagName) >= 0) {
				bb = good_bb = svgedit.utilities.getBBoxOfElementAsPath(elem, addSvgElementFromJson, pathActions);
			} else if (elem.tagName == 'rect') {
				// Look for radius
				var rx = elem.getAttribute('rx');
				var ry = elem.getAttribute('ry');
				if (rx || ry) {
					bb = good_bb = svgedit.utilities.getBBoxOfElementAsPath(elem, addSvgElementFromJson, pathActions);
				}
			}
		}

		if (!good_bb) {

			var matrix = svgedit.math.transformListToTransform(tlist).matrix;
			bb = svgedit.math.transformBox(bb.x, bb.y, bb.width, bb.height, matrix).aabox;

			// Old technique that was exceedingly slow with large documents.
			//
			// Accurate way to get BBox of rotated element in Firefox:
			// Put element in group and get its BBox
			//
			// Must use clone else FF freaks out
			//var clone = elem.cloneNode(true);
			//var g = document.createElementNS(NS.SVG, 'g');
			//var parent = elem.parentNode;
			//parent.appendChild(g);
			//g.appendChild(clone);
			//var bb2 = svgedit.utilities.bboxToObj(g.getBBox());
			//parent.removeChild(g);
		}

	}
	return bb;
};

// TODO: This is problematic with large stroke-width and, for example, a single horizontal line. The calculated BBox extends way beyond left and right sides.
function getStrokeOffsetForBBox(elem) {
	var sw = elem.getAttribute('stroke-width');
	return (!isNaN(sw) && elem.getAttribute('stroke') != 'none') ? sw/2 : 0;
};

// Function: getStrokedBBox
// Get the bounding box for one or more stroked and/or transformed elements
//
// Parameters:
// elems - Array with DOM elements to check
// addSvgElementFromJson - Function to add the path element to the current layer. See canvas.addSvgElementFromJson
// pathActions - If a transform exists, pathActions.resetOrientation() is used. See: canvas.pathActions.
//
// Returns:
// A single bounding box object
svgedit.utilities.getStrokedBBox = function(elems, addSvgElementFromJson, pathActions) {
	if (!elems || !elems.length) {return false;}

	var full_bb;
	$.each(elems, function() {
		if (full_bb) {return;}
		if (!this.parentNode) {return;}
		full_bb = svgedit.utilities.getBBoxWithTransform(this, addSvgElementFromJson, pathActions);
	});

	// This shouldn't ever happen...
	if (full_bb === undefined) {return null;}

	// full_bb doesn't include the stoke, so this does no good!
	// if (elems.length == 1) return full_bb;

	var max_x = full_bb.x + full_bb.width;
	var max_y = full_bb.y + full_bb.height;
	var min_x = full_bb.x;
	var min_y = full_bb.y;

	// If only one elem, don't call the potentially slow getBBoxWithTransform method again.
	if (elems.length === 1) {
		var offset = getStrokeOffsetForBBox(elems[0]);
		min_x -= offset;
		min_y -= offset;
		max_x += offset;
		max_y += offset;
	} else {
		$.each(elems, function(i, elem) {
			var cur_bb = svgedit.utilities.getBBoxWithTransform(elem, addSvgElementFromJson, pathActions);
			if (cur_bb) {
				var offset = getStrokeOffsetForBBox(elem);
				min_x = Math.min(min_x, cur_bb.x - offset);
				min_y = Math.min(min_y, cur_bb.y - offset);
				// TODO: The old code had this test for max, but not min. I suspect this test should be for both min and max
				if (elem.nodeType == 1) {
					max_x = Math.max(max_x, cur_bb.x + cur_bb.width + offset);
					max_y = Math.max(max_y, cur_bb.y + cur_bb.height + offset);
				}
			}
		});
	}

	full_bb.x = min_x;
	full_bb.y = min_y;
	full_bb.width = max_x - min_x;
	full_bb.height = max_y - min_y;
	return full_bb;
};


// Function: svgedit.utilities.getRotationAngleFromTransformList
// Get the rotation angle of the given transform list.
//
// Parameters:
// tlist - List of transforms
// to_rad - Boolean that when true returns the value in radians rather than degrees
//
// Returns:
// Float with the angle in degrees or radians
svgedit.utilities.getRotationAngleFromTransformList = function(tlist, to_rad) {
	if (!tlist) {return 0;} // <svg> elements have no tlist
	var N = tlist.numberOfItems;
	var i;
	for (i = 0; i < N; ++i) {
		var xform = tlist.getItem(i);
		if (xform.type == 4) {
			return to_rad ? xform.angle * Math.PI / 180.0 : xform.angle;
		}
	}
	return 0.0;
};

// Function: svgedit.utilities.getRotationAngle
// Get the rotation angle of the given/selected DOM element
//
// Parameters:
// elem - Optional DOM element to get the angle for
// to_rad - Boolean that when true returns the value in radians rather than degrees
//
// Returns:
// Float with the angle in degrees or radians
svgedit.utilities.getRotationAngle = function(elem, to_rad) {
	var selected = elem || editorContext_.getSelectedElements()[0];
	// find the rotation transform (if any) and set it
	var tlist = svgedit.transformlist.getTransformList(selected);
	return svgedit.utilities.getRotationAngleFromTransformList(tlist, to_rad)
};

// Function getRefElem
// Get the reference element associated with the given attribute value
//
// Parameters:
// attrVal - The attribute value as a string
svgedit.utilities.getRefElem = function(attrVal) {
	return svgedit.utilities.getElem(svgedit.utilities.getUrlFromAttr(attrVal).substr(1));
};

// Function: getElem
// Get a DOM element by ID within the SVG root element.
//
// Parameters:
// id - String with the element's new ID
if (svgedit.browser.supportsSelectors()) {
	svgedit.utilities.getElem = function(id) {
		// querySelector lookup
		return svgroot_.querySelector('#'+id);
	};
} else if (svgedit.browser.supportsXpath()) {
	svgedit.utilities.getElem = function(id) {
		// xpath lookup
		return domdoc_.evaluate(
			'svg:svg[@id="svgroot"]//svg:*[@id="'+id+'"]',
			domcontainer_,
			function() { return svgedit.NS.SVG; },
			9,
			null).singleNodeValue;
	};
} else {
	svgedit.utilities.getElem = function(id) {
		// jQuery lookup: twice as slow as xpath in FF
		return $(svgroot_).find('[id=' + id + ']')[0];
	};
}

// Function: assignAttributes
// Assigns multiple attributes to an element.
//
// Parameters: 
// node - DOM element to apply new attribute values to
// attrs - Object with attribute keys/values
// suspendLength - Optional integer of milliseconds to suspend redraw
// unitCheck - Boolean to indicate the need to use svgedit.units.setUnitAttr
svgedit.utilities.assignAttributes = function(node, attrs, suspendLength, unitCheck) {
	var i;
	for (i in attrs) {
		var ns = (i.substr(0,4) === 'xml:' ? NS.XML :
			i.substr(0,6) === 'xlink:' ? NS.XLINK : null);

		if(ns) {
			node.setAttributeNS(ns, i, attrs[i]);
		} else if(!unitCheck) {
			node.setAttribute(i, attrs[i]);
		} else {
			svgedit.units.setUnitAttr(node, i, attrs[i]);
		}
	}
};

// Function: cleanupElement
// Remove unneeded (default) attributes, makes resulting SVG smaller
//
// Parameters:
// element - DOM element to clean up
svgedit.utilities.cleanupElement = function(element) {
	var defaults = {
		'fill-opacity':1,
		'stop-opacity':1,
		'opacity':1,
		'stroke':'none',
		'stroke-dasharray':'none',
		'stroke-linejoin':'miter',
		'stroke-linecap':'butt',
		'stroke-opacity':1,
		'stroke-width':1,
		'rx':0,
		'ry':0
	};

	if (element.nodeName === 'ellipse') {
		// Ellipse elements requires rx and ry attributes
		delete defaults.rx;
		delete defaults.ry;
	}

	var attr;
	for (attr in defaults) {
		var val = defaults[attr];
		if(element.getAttribute(attr) == val) {
			element.removeAttribute(attr);
		}
	}
};

// Function: snapToGrid
// round value to for snapping
// NOTE: This function did not move to svgutils.js since it depends on curConfig.
svgedit.utilities.snapToGrid = function(value) {
	var stepSize = editorContext_.getSnappingStep();
	var unit = editorContext_.getBaseUnit();
	if (unit !== "px") {
		stepSize *= svgedit.units.getTypeMap()[unit];
	}
	value = Math.round(value/stepSize)*stepSize;
	return value;
};

svgedit.utilities.preg_quote = function (str, delimiter) {
  // From: http://phpjs.org/functions
  return String(str).replace(new RegExp('[.\\\\+*?\\[\\^\\]$(){}=!<>|:\\' + (delimiter || '') + '-]', 'g'), '\\$&');
};

/**
* @param {string} globalCheck A global which can be used to determine if the script is already loaded
* @param {array} scripts An array of scripts to preload (in order)
* @param {function} cb The callback to execute upon load.
*/
svgedit.utilities.executeAfterLoads = function (globalCheck, scripts, cb) {
	return function () {
		var args = arguments;
		function endCallback () {
			cb.apply(null, args);
		}
		if (window[globalCheck]) {
			endCallback();
		}
		else {
			scripts.reduceRight(function (oldFunc, script) {
				return function () {
					$.getScript(script, oldFunc);
				};
			}, endCallback)();
		}
	};
};

svgedit.utilities.buildCanvgCallback = function (callCanvg) {
	return svgedit.utilities.executeAfterLoads('canvg', ['canvg/rgbcolor.js', 'canvg/canvg.js'], callCanvg);
};

svgedit.utilities.buildJSPDFCallback = function (callJSPDF) {
	return svgedit.utilities.executeAfterLoads('RGBColor', ['canvg/rgbcolor.js'], function () {
		var arr = [];
		if (!RGBColor || RGBColor.ok === undef) { // It's not our RGBColor, so we'll need to load it
			arr.push('canvg/rgbcolor.js');
		}
		svgedit.utilities.executeAfterLoads('jsPDF', arr.concat('jspdf/underscore-min.js', 'jspdf/jspdf.min.js', 'jspdf/jspdf.plugin.svgToPdf.js'), callJSPDF)();
	});
};


/**
 * Prevents default browser click behaviour on the given element
 * @param img - The DOM element to prevent the click on
 */
svgedit.utilities.preventClickDefault = function(img) {
	$(img).click(function(e){e.preventDefault();});
};

/**
 * Create a clone of an element, updating its ID and its children's IDs when needed
 * @param {Element} el - DOM element to clone
 * @param {function()} getNextId - function the get the next unique ID.
 * @returns {Element}
 */
svgedit.utilities.copyElem = function(el, getNextId) {
	// manually create a copy of the element
	var new_el = document.createElementNS(el.namespaceURI, el.nodeName);
	$.each(el.attributes, function(i, attr) {
		if (attr.localName != '-moz-math-font-style') {
			new_el.setAttributeNS(attr.namespaceURI, attr.nodeName, attr.value);
		}
	});
	// set the copied element's new id
	new_el.removeAttribute('id');
	new_el.id = getNextId();

	// Opera's "d" value needs to be reset for Opera/Win/non-EN
	// Also needed for webkit (else does not keep curved segments on clone)
	if (svgedit.browser.isWebkit() && el.nodeName == 'path') {
		var fixed_d = svgedit.utilities.convertPath(el);
		new_el.setAttribute('d', fixed_d);
	}

	// now create copies of all children
	$.each(el.childNodes, function(i, child) {
		switch(child.nodeType) {
			case 1: // element node
				new_el.appendChild(svgedit.utilities.copyElem(child, getNextId));
				break;
			case 3: // text node
				new_el.textContent = child.nodeValue;
				break;
			default:
				break;
		}
	});

	if ($(el).data('gsvg')) {
		$(new_el).data('gsvg', new_el.firstChild);
	} else if ($(el).data('symbol')) {
		var ref = $(el).data('symbol');
		$(new_el).data('ref', ref).data('symbol', ref);
	} else if (new_el.tagName == 'image') {
		preventClickDefault(new_el);
	}
	return new_el;
};


/**
 * TODO: refactor callers in convertPath to use getPathDFromSegments instead of this function.
 * Legacy code refactored from svgcanvas.pathActions.convertPath
 * @param letter - path segment command
 * @param {Array.<Array.<number>>} points - x,y points.
 * @param {Array.<Array.<number>>=} morePoints - x,y points
 * @param {Array.<number>=}lastPoint - x,y point
 * @returns {string}
 */
function pathDSegment(letter, points, morePoints, lastPoint) {
	$.each(points, function(i, pnt) {
		points[i] = svgedit.units.shortFloat(pnt);
	});
	var segment = letter + points.join(' ');
	if( morePoints) {
		segment += ' ' + morePoints.join(' ');
	}
	if( lastPoint) {
		segment += ' ' + svgedit.units.shortFloat(lastPoint);
	}
	return segment;
}

// this is how we map paths to our preferred relative segment types
var pathMap = [0, 'z', 'M', 'm', 'L', 'l', 'C', 'c', 'Q', 'q', 'A', 'a',
	'H', 'h', 'V', 'v', 'S', 's', 'T', 't'];


/**
 * TODO: move to pathActions.js when migrating rest of pathActions out of svgcanvas.js
 * Convert a path to one with only absolute or relative values
 * @param {Object} path - the path to convert
 * @param {boolean} toRel - true of convert to relative
 * @returns {string}
 */
svgedit.utilities.convertPath = function(path, toRel) {
	var i;
	var segList = path.pathSegList;
	var len = segList.numberOfItems;
	var curx = 0, cury = 0;
	var d = '';
	var last_m = null;

	for (i = 0; i < len; ++i) {
		var seg = segList.getItem(i);
		// if these properties are not in the segment, set them to zero
		var x = seg.x || 0,
				y = seg.y || 0,
				x1 = seg.x1 || 0,
				y1 = seg.y1 || 0,
				x2 = seg.x2 || 0,
				y2 = seg.y2 || 0;

		var type = seg.pathSegType;
		var letter = pathMap[type]['to'+(toRel?'Lower':'Upper')+'Case']();

		switch (type) {
			case 1: // z,Z closepath (Z/z)
				d += 'z';
				break;
			case 12: // absolute horizontal line (H)
				x -= curx;
			case 13: // relative horizontal line (h)
				if (toRel) {
					curx += x;
					letter = 'l';
				} else {
					x += curx;
					curx = x;
					letter = 'L';
				}
				// Convert to "line" for easier editing
				d += pathDSegment(letter,[[x, cury]]);
				break;
			case 14: // absolute vertical line (V)
				y -= cury;
			case 15: // relative vertical line (v)
				if (toRel) {
					cury += y;
					letter = 'l';
				} else {
					y += cury;
					cury = y;
					letter = 'L';
				}
				// Convert to "line" for easier editing
				d += pathDSegment(letter,[[curx, y]]);
				break;
			case 2: // absolute move (M)
			case 4: // absolute line (L)
			case 18: // absolute smooth quad (T)
				x -= curx;
				y -= cury;
			case 5: // relative line (l)
			case 3: // relative move (m)
				// If the last segment was a "z", this must be relative to
				if (last_m && segList.getItem(i-1).pathSegType === 1 && !toRel) {
					curx = last_m[0];
					cury = last_m[1];
				}

			case 19: // relative smooth quad (t)
				if (toRel) {
					curx += x;
					cury += y;
				} else {
					x += curx;
					y += cury;
					curx = x;
					cury = y;
				}
				if (type === 3) {last_m = [curx, cury];}

				d += pathDSegment(letter,[[x, y]]);
				break;
			case 6: // absolute cubic (C)
				x -= curx; x1 -= curx; x2 -= curx;
				y -= cury; y1 -= cury; y2 -= cury;
			case 7: // relative cubic (c)
				if (toRel) {
					curx += x;
					cury += y;
				} else {
					x += curx; x1 += curx; x2 += curx;
					y += cury; y1 += cury; y2 += cury;
					curx = x;
					cury = y;
				}
				d += pathDSegment(letter,[[x1, y1], [x2, y2], [x, y]]);
				break;
			case 8: // absolute quad (Q)
				x -= curx; x1 -= curx;
				y -= cury; y1 -= cury;
			case 9: // relative quad (q)
				if (toRel) {
					curx += x;
					cury += y;
				} else {
					x += curx; x1 += curx;
					y += cury; y1 += cury;
					curx = x;
					cury = y;
				}
				d += pathDSegment(letter,[[x1, y1],[x, y]]);
				break;
			case 10: // absolute elliptical arc (A)
				x -= curx;
				y -= cury;
			case 11: // relative elliptical arc (a)
				if (toRel) {
					curx += x;
					cury += y;
				} else {
					x += curx;
					y += cury;
					curx = x;
					cury = y;
				}
				d += pathDSegment(letter,[[seg.r1, seg.r2]], [
						seg.angle,
						(seg.largeArcFlag ? 1 : 0),
						(seg.sweepFlag ? 1 : 0)
					], [x, y]
				);
				break;
			case 16: // absolute smooth cubic (S)
				x -= curx; x2 -= curx;
				y -= cury; y2 -= cury;
			case 17: // relative smooth cubic (s)
				if (toRel) {
					curx += x;
					cury += y;
				} else {
					x += curx; x2 += curx;
					y += cury; y2 += cury;
					curx = x;
					cury = y;
				}
				d += pathDSegment(letter,[[x2, y2],[x, y]]);
				break;
		} // switch on path segment type
	} // for each segment
	return d;
};


}());