/
jquery.queryback.js
298 lines (194 loc) · 8.01 KB
/
jquery.queryback.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
/**
* Queryback by Thinkbigr (@thinkbigr)
* http://www.thinkbi.gr/
*
* Copyright 2014, Thinkbigr
* Free to use under the MIT license.
* http://www.opensource.org/licenses/mit-license.php
*
* Date: Wednesday, January 15, 2014
*/
/**
* Extracts media queries from included and embedded style sheets
* and fires events when they're entered and exited
*
* @author Allan Kiezel <allan@thinkbi.gr> (@allankiezel)
*/
(function($, window, document, undefined) {
'use strict';
var Queryback = {
name: 'Queryback',
version: '0.1',
bodyFontSize: '16px', // Font size of body element - used for em conversion
combinedStyles: null, // Combined styles of all embedded and external stylesheets
defaults: {
selector: 'link, style'
},
el: null, // HTMLElement of selected element
$el: null, // jQuery wrapped element
externalStylesheetCount: 0, // Stores external stylesheet count which helps with aysnc requests progress
mediaQueries: [], // Array of media queries objects indexed by name (properties: name, min, max, mediaType)
regex: { // Regular expressions used throughout library to parse media query components
media: /(\/\*\sQueryback Name:\s([A-Za-z0-9_-]+)\s\*\/\s*[\n\r]+@media[\sa-zA-Z]+.+{)+/gmi,
queryName: /\/\*\sQueryback Name:\s([A-Za-z0-9_-]+)\s\*\/\n*/,
mediaType: /(?:@media\s+)(only\s+)?([a-zA-Z]+)\s?/,
minWidth: /\(\s*min\-width\s*:\s*(\s*[0-9\.]+)(px|em)\s*\)/,
maxWidth: /\(\s*max\-width\s*:\s*(\s*[0-9\.]+)(px|em)\s*\)/
},
settings: null, // Combination of defaults merge with passed in options
/**
* Intializes the stylesheet parsing, etc.
*
* @constructor
* @this Queryback
* @param {HTMLElement} el Selected HTML element
*/
init: function (el) {
// Cleanup all previously modified properties
this.cleanup();
this.el = el;
this.$el = $(el);
// Let's get this parsing started!
try {
this.startStylesheetProcessing($(this.settings.selector));
} catch (error) {
console.log(error);
}
},
/**
* Iterate over stylesheets and pass each to the parsing engine
*
* @param {array} stylesheets jQuery wrapped stylesheet elements
*/
startStylesheetProcessing: function (stylesheets) {
var stylesheetContent = '';
var externalStylesheets = [];
var externalStylesheetCount = 0;
for (var i = 0, len = stylesheets.length; i < len; i++) {
var $stylesheet = stylesheets[i];
if ($stylesheet.tagName === 'LINK') { // Stylesheet is external
externalStylesheetCount += 1;
externalStylesheets.push($stylesheet.href);
} else { // Stylesheet is embedded
stylesheetContent += $stylesheet.textContent || $stylesheet.innerText || $stylesheet.innerHTML;
}
}
this.combinedStyles = stylesheetContent;
this.externalStylesheetCount = externalStylesheetCount;
// Check to make sure we have external stylesheets or embedded content before proceeding
if (externalStylesheetCount > 0 || stylesheetContent !== '') {
if (externalStylesheetCount === 0) {
this.parseStyles(stylesheetContent);
return;
}
// Retrieve the remote stylesheets
this.retrieveExternalStylesheets(externalStylesheets);
}
},
/**
* Parses styles for media queries
*
* @param {string} styles Combined styles (optional)
*/
parseStyles: function (styles) {
var styles = styles || this.combinedStyles;
// Remove line feeds, carriage returns, and white space from beginning and end of lines
var content = styles.replace(/^[\n\r\s]+|[\n\r\s]+$/gm, '');
var mediaRegex = this.regex.media;
var mediaQueries = content.match(mediaRegex);
if (mediaQueries.length > 0) {
for (var i = 0, len = mediaQueries.length; i < len; i++) {
this.parseMediaQuery(mediaQueries[i]);
}
}
},
/**
* Responsible for extracting name and expressions from the media query
*
* @param {string} mediaQuery Media Query block
* @todo Add to an errors array if part of the query isn't formatted
*/
parseMediaQuery: function (mediaQuery) {
var queryNameRegex = this.regex.queryName;
var queryName = queryNameRegex.exec(mediaQuery)[1];
mediaQuery = mediaQuery.replace(queryNameRegex, '');
// Split comma-separated expressions, because I'm no regex expert
var subQueries = mediaQuery.split(',');
for (var i = 0, len = subQueries.length; i < len; i++) {
var subQuery = subQueries[i];
var mediaQueryObj = {
name: queryName,
mediaType: subQuery.split('(')[0].match(this.regex.mediaType) && RegExp.$2 || 'all',
minWidth: subQuery.match(this.regex.minWidth) && parseFloat(RegExp.$1) + (RegExp.$2 || ''),
maxWidth: subQuery.match(this.regex.maxWidth) && parseFloat(RegExp.$1) + (RegExp.$2 || '')
};
this.generateMediaQueryCallback(mediaQueryObj);
}
},
/**
* Generate callbacks from sub-query array
*
* @param {object} mediaQuery Contains media query information (e.g. media type, min-width, etc.)
*/
generateMediaQueryCallback: function (mediaQuery) {
/* Sample object
{
name: "ipad",
mediaType: "screen",
minWidth: "768px",
maxWidth: "1024px"
}
*/
this.mediaQueries.push(mediaQuery);
},
/**
* Iterate over external stylesheets and pass-thru each to be retrieved
*
* @param {array} stylesheets External stylesheets
*/
retrieveExternalStylesheets: function (stylesheets) {
for (var i = 0, len = stylesheets.length; i < len; i++) {
this.retrieveExternalStylesheet(stylesheets[i]);
}
},
/**
* Uses $.ajax to asynchronously retrieve stylesheet contents
*
* @param {string} url Stylesheet external url
* @return {string} Stylesheet contents
*/
retrieveExternalStylesheet: function (url) {
var request = $.ajax({
url: url,
context: this
})
.done(function(data, textStatus, jqXHR) {
this.combinedStyles += data;
var externalStylesheetCount = this.externalStylesheetCount -= 1;
if (externalStylesheetCount === 0) {
this.parseStyles();
}
})
.fail(function() {
});
},
/**
* Cleans up all properties that were previously modified
*/
cleanup: function () {
this.el = null;
this.$el = null;
this.combinedStyles = null;
// Reset external stylesheet count
this.externalStylesheetCount = 0;
}
};
$.fn.queryback = function () {
Queryback.settings = $.extend(Queryback.defaults, arguments[0]);
// Loop through all selected elements (ie: document) and run through Queryback
return this.each(function() {
Queryback.init.call(Queryback, this);
return this;
});
};
}(jQuery, this, this.document));