Files
YellowLabTools/lib/tools/colorDiff.js
T

92 lines
2.6 KiB
JavaScript

var debug = require('debug')('ylt:colorDiff');
var diff = require('color-diff');
var parse = require('parse-color');
var colorDiff = function() {
var COLOR_DIFF_THRESHOLD = 0.9;
this.compareAllColors = function(data) {
debug('Starting to compare all colors...');
var offenders = data.toolsResults.phantomas.offenders.cssColors;
var colors = (offenders) ? this.parseAllColors(offenders) : [];
var result = [];
// Compare colors to each other
for (var i = 0; i < colors.length - 1 ; i++) {
for (var j = i + 1; j < colors.length; j++) {
debug('Comparing color %s with color %s', colors[i].original, colors[j].original);
if (this.compareTwoColors(colors[i], colors[j])) {
debug('Colors are similar!');
result.push({
color1: colors[i].original,
color2: colors[j].original,
isDark: (colors[i].Lab.L < 60)
});
}
}
}
data.toolsResults.colorDiff = {
metrics: {
similarColors: result.length
},
offenders: {
similarColors: result
}
};
return data;
};
this.parseAllColors = function(offenders) {
var parsedOffenders = offenders.map(this.parseOffender);
var deduplicatedColors = {};
parsedOffenders.forEach(function(color) {
if (color !== null) {
deduplicatedColors[color] = color;
}
});
return Object.keys(deduplicatedColors).map(this.parseColor);
};
this.parseOffender = function(offender) {
var regexResult = /^(.*) \(\d+ times\)$/.exec(offender);
return regexResult ? regexResult[1] : null;
};
this.parseColor = function(color) {
var colorArray = parse(color).rgba;
var obj = {
R: colorArray[0],
G: colorArray[1],
B: colorArray[2],
A: colorArray[3]
};
obj.Lab = diff.rgb_to_lab(obj);
obj.original = color;
return obj;
};
this.compareTwoColors = function(color1, color2) {
if (color1.A !== color2.A) {
debug('Comparison not possible, because the alpha channel is different');
return false;
}
var delta = diff.diff(color1.Lab, color2.Lab);
debug('Delta is %d', delta);
return delta <= COLOR_DIFF_THRESHOLD;
};
};
module.exports = new colorDiff();