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index.js
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index.js
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/**
* Created by Android22 on 5/31/2014.
*/
(function (PrefixFree, Color, Incrementable, $) {
'use strict';
var app = angular.module('colorContrast', ['angularSpectrumColorpicker']),
UPDATE_SCORE = 'UPDATE_SCORE',
UPDATE_FAV_ICON = 'UPDATE_FAV_ICON',
messages = {
'semitransparent': 'The background is semi-transparent, so the contrast ratio cannot be precise. Depending on what’s going to be underneath, it could be any of the following:',
'fail': 'Fails WCAG 2.0 :-(',
'aa-large': 'Passes AA for large text (above 18pt or bold above 14pt)',
'aa': 'Passes AA level for any size text and AAA for large text (above 18pt or bold above 14pt)',
'aaa': 'Passes AAA level for any size text'
},
levels = {
'fail': {
range: [0, 3],
color: 'hsl(0, 100%, 40%)'
},
'aa-large': {
range: [3, 4.5],
color: 'hsl(40, 100%, 45%)'
},
'aa': {
range: [4.5, 7],
color: 'hsl(80, 60%, 45%)'
},
'aaa': {
range: [7, 22],
color: 'hsl(95, 60%, 41%)'
}
};
function debounce(func, wait) {
// we need to save these in the closure
var timeout, args, context, timestamp;
return function () {
// save details of latest call
context = this;
args = [].slice.call(arguments, 0);
timestamp = new Date();
// this is where the magic happens
var later = function () {
// how long ago was the last call
var last = (new Date()) - timestamp;
// if the latest call was less that the wait period ago
// then we reset the timeout to wait for the difference
if (last < wait) {
timeout = window.setTimeout(later, wait - last);
// or if not we can null out the timer and run the latest
} else {
timeout = null;
func.apply(context, args);
}
};
// we only need to set the timer now if one isn't already running
if (!timeout) {
timeout = window.setTimeout(later, wait);
}
};
}
function isValidColor(colorStr) {
var elm = $('#test-color')[0],
oldValue = elm.style.backgroundColor;
elm.style.background = colorStr;
return elm.style.backgroundColor !== oldValue;
}
function rangeIntersect(min, max, upper, lower) {
return (max < upper ? max : upper) - (lower < min ? min : lower);
}
function parseHashPath(hashPath) {
var arr,
colors = {
background: 'white',
text: 'black'
};
if (hashPath && hashPath.length > 0) {
hashPath = hashPath.substr(1, hashPath.length - 1);
arr = hashPath.split('-on-');
if (arr[0]) {
colors.text = arr[0];
}
if (arr[1]) {
colors.background = arr[1];
}
}
return colors;
}
function IndexCtrl($scope, $timeout, $location) {
var self = this;
self.updateColorsFromPath = function () {
var colors = parseHashPath($location.path());
self.backgroundColor = colors.background;
self.textColor = colors.text;
};
self.updateColorsFromPath();
window.onhashchange = function () {
self.updateColorsFromPath();
$scope.$apply(function () {
self.notifyChange();
});
};
self.notifyChange = function () {
if (isValidColor(self.textColor) || isValidColor(self.backgroundColor)) {
$location.path(self.textColor + '-on-' + self.backgroundColor);
$scope.$broadcast(UPDATE_SCORE);
}
};
self.updateScore = function (bgColor, textColor) {
self.contrast = bgColor.contrast(textColor);
var min = self.contrast.min,
max = self.contrast.max,
range = max - min,
classes = [],
percentages = [],
level,
bounds,
lower,
upper,
i,
stops,
previousPercentage,
info,
color,
percentage,
gradient;
for (level in levels) {
if (levels.hasOwnProperty(level)) {
bounds = levels[level].range;
lower = bounds[0];
upper = bounds[1];
if (min < upper && max >= lower) {
classes.push(level);
percentages.push({
level: level,
percentage: 100 * rangeIntersect(min, max, upper, lower) / range
});
}
}
}
self.ratioErrorExplain = {};
if (self.contrast.error) {
self.ratioErrorExplain.message = '±' + self.contrast.error;
self.ratioErrorExplain.tooltip = min + ' - ' + max;
}
self.results = {};
self.output = {};
if (classes.length <= 1) {
self.results.message = messages[classes[0]];
self.output.backgroundImage = '';
self.output.backgroundColor = levels[classes[0]].color;
} else {
self.results.message = messages.semitransparent;
self.results.cases = [];
for (i = 0; i < classes.length; i += 1) {
self.results.cases.push(messages[classes[i]]);
}
// Create gradient illustrating levels
stops = [];
previousPercentage = 0;
for (i = 0; i < 2 * percentages.length; i += 1) {
info = percentages[i % percentages.length];
level = info.level;
color = levels[level].color;
percentage = previousPercentage + info.percentage / 2;
stops.push(color + ' ' + previousPercentage + '%', color + ' ' + percentage + '%');
previousPercentage = percentage;
}
if (PrefixFree.functions.indexOf('linear-gradient') > -1) {
// Prefixed implementation
gradient = 'linear-gradient(-45deg, ' + stops.join(', ') + ')';
self.output.backgroundImage = PrefixFree.prefix + gradient;
} else {
gradient = 'linear-gradient(135deg, ' + stops.join(', ') + ')';
self.output.backgroundImage = gradient;
}
}
self.output.classes = classes.join(' ');
};
self.swapColor = function () {
var temp = this.backgroundColor;
this.backgroundColor = this.textColor;
this.textColor = temp;
this.notifyChange();
};
self.colorPickerOptions = {
preferredFormat: 'hex',
showAlpha: true,
clickoutFiresChange: true
};
$timeout(function () {
self.notifyChange();
});
}
IndexCtrl.$inject = ['$scope', '$timeout', '$location'];
app.controller('IndexCtrl', IndexCtrl);
// calc-color-score directive
function calcColorScore($timeout) {
return {
link: function (scope, elm, attrs) {
scope.$on(UPDATE_SCORE, function () {
$timeout(function () {
var bgColor = new Color(window.getComputedStyle(elm[0]).backgroundColor),
textColor = new Color(window.getComputedStyle(elm[0]).color),
callbackFn = scope.$eval(attrs.calcColorScore);
callbackFn(bgColor, textColor);
scope.$broadcast(UPDATE_FAV_ICON, bgColor, textColor);
});
});
}
};
}
calcColorScore.$inject = ['$timeout'];
app.directive('calcColorScore', calcColorScore);
// incrementable-text directive
function incrementableText() {
return {
link: function (scope, elm) {
/*jshint -W031 */
var o = new Incrementable(elm[0]);
o = null;
/*jshint +W031 */
}
};
}
incrementableText.$inject = [];
app.directive('incrementableText', incrementableText);
// auto-length input
function autoLength() {
return {
link: function (scope, elm) {
if (elm.is('input')) {
elm[0].oninput = function () {
elm[0].style.width = elm[0].value.length * 0.56 + 'em';
elm[0].style.width = elm[0].value.length + 'ch';
};
}
}
};
}
autoLength.$inject = [];
app.directive('autoLength', autoLength);
// favorite-icon directive
function favoriteIcon() {
return {
link: function (scope, elm, attrs) {
var document = window.document,
canvas = document.createElement('canvas'),
ctx = canvas.getContext('2d'),
updateFavIcon = debounce(function (bgColor, textColor) {
ctx.clearRect(0, 0, 16, 16);
ctx.fillStyle = bgColor.toString();
ctx.fillRect(0, 0, 8, 16);
ctx.fillStyle = textColor.toString();
ctx.fillRect(8, 0, 8, 16);
elm.attr('href', canvas.toDataURL());
}, 300);
canvas.width = canvas.height = 16;
document.body.appendChild(canvas);
scope.$on(UPDATE_FAV_ICON, function (e, bgColor, textColor) {
updateFavIcon(bgColor, textColor);
});
}
};
}
favoriteIcon.$inject = [];
app.directive('favoriteIcon', favoriteIcon);
}(window.PrefixFree, window.Color, window.Incrementable, window.$));