/**
   * Package: svgedit.browser
   *
   * Licensed under the Apache License, Version 2
   *
   * Copyright(c) 2010 Jeff Schiller
   * Copyright(c) 2010 Alexis Deveria
   */
  
  // Dependencies:
  // 1) jQuery (for $.alert())
  
  var svgedit = svgedit || {};
  
  (function() {
  
  if (!svgedit.browser) {
  	svgedit.browser = {};
  }
  var supportsSvg_ = (function() {
          return !!document.createElementNS && !!document.createElementNS('http://www.w3.org/2000/svg', 'svg').createSVGRect;
  })();
  svgedit.browser.supportsSvg = function() { return supportsSvg_; }
  if(!svgedit.browser.supportsSvg()) {
  	window.location = "browser-not-supported.html";
  }
  else{
  
  var svgns = 'http://www.w3.org/2000/svg';
  var userAgent = navigator.userAgent;
  var svg = document.createElementNS(svgns, 'svg');
  
  // Note: Browser sniffing should only be used if no other detection method is possible
  var isOpera_ = !!window.opera;
  var isWebkit_ = userAgent.indexOf("AppleWebKit") >= 0;
  var isGecko_ = userAgent.indexOf('Gecko/') >= 0;
  var isIE_ = userAgent.indexOf('MSIE') >= 0;
  var isChrome_ = userAgent.indexOf('Chrome/') >= 0;
  var isWindows_ = userAgent.indexOf('Windows') >= 0;
  var isMac_ = userAgent.indexOf('Macintosh') >= 0;
  
  var supportsSelectors_ = (function() {
  	return !!svg.querySelector;
  })();
  
  var supportsXpath_ = (function() {
  	return !!document.evaluate;
  })();
  
  // segList functions (for FF1.5 and 2.0)
  var supportsPathReplaceItem_ = (function() {
  	var path = document.createElementNS(svgns, 'path');
  	path.setAttribute('d','M0,0 10,10');
  	var seglist = path.pathSegList;
  	var seg = path.createSVGPathSegLinetoAbs(5,5);
  	try {
  		seglist.replaceItem(seg, 0);
  		return true;
  	} catch(err) {}
  	return false;
  })();
  
  var supportsPathInsertItemBefore_ = (function() {
  	var path = document.createElementNS(svgns,'path');
  	path.setAttribute('d','M0,0 10,10');
  	var seglist = path.pathSegList;
  	var seg = path.createSVGPathSegLinetoAbs(5,5);
  	try {
  		seglist.insertItemBefore(seg, 0);
  		return true;
  	} catch(err) {}
  	return false;
  })();
  
  // text character positioning (for IE9)
  var supportsGoodTextCharPos_ = (function() {
  	var retValue = false;
  	var svgroot = document.createElementNS(svgns, 'svg');
  	var svgcontent = document.createElementNS(svgns, 'svg');
  	document.documentElement.appendChild(svgroot);
  	svgcontent.setAttribute('x', 5);
  	svgroot.appendChild(svgcontent);
  	var text = document.createElementNS(svgns,'text');
  	text.textContent = 'a';
  	svgcontent.appendChild(text);
  	var pos = text.getStartPositionOfChar(0).x;
  	document.documentElement.removeChild(svgroot);
  	return (pos === 0);
  })();
  
  var supportsPathBBox_ = (function() {
  	var svgcontent = document.createElementNS(svgns, 'svg');
  	document.documentElement.appendChild(svgcontent);
  	var path = document.createElementNS(svgns, 'path');
  	path.setAttribute('d','M0,0 C0,0 10,10 10,0');
  	svgcontent.appendChild(path);
  	var bbox = path.getBBox();
  	document.documentElement.removeChild(svgcontent);
  	return (bbox.height > 4 && bbox.height < 5);
  })();
  
  // Support for correct bbox sizing on groups with horizontal/vertical lines
  var supportsHVLineContainerBBox_ = (function() {
  	var svgcontent = document.createElementNS(svgns, 'svg');
  	document.documentElement.appendChild(svgcontent);
  	var path = document.createElementNS(svgns, 'path');
  	path.setAttribute('d','M0,0 10,0');
  	var path2 = document.createElementNS(svgns, 'path');
  	path2.setAttribute('d','M5,0 15,0');
  	var g = document.createElementNS(svgns, 'g');
  	g.appendChild(path);
  	g.appendChild(path2);
  	svgcontent.appendChild(g);
  	var bbox = g.getBBox();
  	document.documentElement.removeChild(svgcontent);
  	// Webkit gives 0, FF gives 10, Opera (correctly) gives 15
  	return (bbox.width == 15);
  })();
  
  var supportsEditableText_ = (function() {
  	// TODO: Find better way to check support for this
  	return isOpera_;
  })();
  
  var supportsGoodDecimals_ = (function() {
  	// Correct decimals on clone attributes (Opera < 10.5/win/non-en)
  	var rect = document.createElementNS(svgns, 'rect');
  	rect.setAttribute('x',.1);
  	var crect = rect.cloneNode(false);
  	var retValue = (crect.getAttribute('x').indexOf(',') == -1);
  	if(!retValue) {
  		$.alert("NOTE: This version of Opera is known to contain bugs in SVG-edit.
  \
  		Please upgrade to the <a href='http://opera.com'>latest version</a> in which the problems have been fixed.");
  	}
  	return retValue;
  })();
  
  var supportsNonScalingStroke_ = (function() {
  	var rect = document.createElementNS(svgns, 'rect');
  	rect.setAttribute('style','vector-effect:non-scaling-stroke');
  	return rect.style.vectorEffect === 'non-scaling-stroke';
  })();
  
  var supportsNativeSVGTransformLists_ = (function() {
  	var rect = document.createElementNS(svgns, 'rect');
  	var rxform = rect.transform.baseVal;
  	
  	var t1 = svg.createSVGTransform();
  	rxform.appendItem(t1);
  	return rxform.getItem(0) == t1;
  })();
  
  // Public API
  
  svgedit.browser.isOpera = function() { return isOpera_; }
  svgedit.browser.isWebkit = function() { return isWebkit_; }
  svgedit.browser.isGecko = function() { return isGecko_; }
  svgedit.browser.isIE = function() { return isIE_; }
  svgedit.browser.isChrome = function() { return isChrome_; }
  svgedit.browser.isWindows = function() { return isWindows_; }
  svgedit.browser.isMac = function() { return isMac_; }
  
  svgedit.browser.supportsSelectors = function() { return supportsSelectors_; }
  svgedit.browser.supportsXpath = function() { return supportsXpath_; }
  
  svgedit.browser.supportsPathReplaceItem = function() { return supportsPathReplaceItem_; }
  svgedit.browser.supportsPathInsertItemBefore = function() { return supportsPathInsertItemBefore_; }
  svgedit.browser.supportsPathBBox = function() { return supportsPathBBox_; }
  svgedit.browser.supportsHVLineContainerBBox = function() { return supportsHVLineContainerBBox_; }
  svgedit.browser.supportsGoodTextCharPos = function() { return supportsGoodTextCharPos_; }
  svgedit.browser.supportsEditableText = function() { return supportsEditableText_; }
  svgedit.browser.supportsGoodDecimals = function() { return supportsGoodDecimals_; }
  svgedit.browser.supportsNonScalingStroke = function() { return supportsNonScalingStroke_; }
  svgedit.browser.supportsNativeTransformLists = function() { return supportsNativeSVGTransformLists_; }
  
  }
  
  })();