|
| 1 | + |
| 2 | +class CSSParser { |
| 3 | + static transform(string) { |
| 4 | + if(!string) return null; |
| 5 | + |
| 6 | + var number = '[+-]?\\d+?(?:\\.\\d+)?'; |
| 7 | + |
| 8 | + var length = `${number}(px|em|ex|rem|vw|vh|vmin|vmax|in|cm|mm|pt|pc)`; |
| 9 | + var percent = `${number}(%)`; |
| 10 | + var dimension = `${number}(%|px|em|ex|rem|vw|vh|vmin|vmax|in|cm|mm|pt|pc)`; |
| 11 | + var angle = `${number}(deg|rad|turn)`; |
| 12 | + |
| 13 | + var translate = new RegExp(`\\s*(${dimension}|0)\\s*(?:,\\s*(${dimension}|0)\\s*)?`); |
| 14 | + var translateXYZ = new RegExp(`\\s*(${dimension}|0)\\s*`); |
| 15 | + var translate3d = new RegExp(`\\s*(${dimension}|0)\\s*,\\s*(${dimension}|0)\\s*,\\s*(${dimension}|0)\\s*`); |
| 16 | + |
| 17 | + var rotate = new RegExp(`\\s*(${angle}|0)\\s*`); |
| 18 | + var rotate3d = new RegExp(`\\s*${number}\\s*,\\s*${number}\\s*,\\s*${number}\\s*,\\s*(${angle}|0)\\s*`); |
| 19 | + |
| 20 | + var skew = new RegExp(`\\s*(${angle}|0)\\s*(?:,\\s*(${angle}|0)\\s*)?`); |
| 21 | + var skewXY = new RegExp(`\\s*(${angle}|0)\\s*`); |
| 22 | + |
| 23 | + var perspective = new RegExp(`\\s*(${length}|0)\\s*`); |
| 24 | + |
| 25 | + var functions = /\b((?:matrix|translate|scale|rotate|skew|perspective)(?:X|Y|Z|3d)?)\((.*?)\)/g; |
| 26 | + |
| 27 | + var results = []; |
| 28 | + var result; |
| 29 | + while(result = functions.exec(string)) |
| 30 | + { |
| 31 | + var name = result[1]; |
| 32 | + var args = result[2]; |
| 33 | + var values; |
| 34 | + switch(name) { |
| 35 | + case 'matrix': values = args.split(','); if(values.length !== 6) return null; break; |
| 36 | + case 'matrix3d': values = args.split(','); if(values.length !== 16) return null; break; |
| 37 | + case 'translate': values = args.match(translate); break; |
| 38 | + case 'translateX': |
| 39 | + case 'translateY': |
| 40 | + case 'translateZ': values = args.match(translateXYZ); break; |
| 41 | + case 'translate3d': values = args.match(translate3d); break; |
| 42 | + case 'scale': |
| 43 | + case 'scaleX': |
| 44 | + case 'scaleY': |
| 45 | + case 'scaleZ': |
| 46 | + case 'scale3d': values = args.split(','); break; |
| 47 | + case 'rotate': |
| 48 | + case 'rotateX': |
| 49 | + case 'rotateY': |
| 50 | + case 'rotateZ': values = args.match(rotate); break; |
| 51 | + case 'rotate3d': values = args.match(rotate3d); break; |
| 52 | + case 'skew': values = args.match(skew); break; |
| 53 | + case 'skewX': |
| 54 | + case 'skewY': values = args.match(skewXY); break; |
| 55 | + case 'perspective': values = args.match(perspective); break; |
| 56 | + default: return null; // An invalid or unimplemented transform function? (E.g. skewZ, perspectiveX) |
| 57 | + } |
| 58 | + |
| 59 | + // Parse values into floats |
| 60 | + if(/^(matrix|scale)/.test(name)) // unit-less |
| 61 | + { |
| 62 | + values = values.map(value => parseFloat(value)); |
| 63 | + } |
| 64 | + |
| 65 | + else // Some functions have tuples of [value, unit] |
| 66 | + { |
| 67 | + values = values.slice(1).reduce((prev, value, index) => { |
| 68 | + if(index%2) prev[prev.length - 1].push(value); |
| 69 | + else prev.push([parseFloat(value)]); |
| 70 | + return prev; |
| 71 | + }, []); |
| 72 | + // .map((value, index) => index%2? value : parseFloat(value)); |
| 73 | + |
| 74 | + switch(name) { |
| 75 | + case 'translate': |
| 76 | + values[0].push('width'); |
| 77 | + if(values[1]) values[1].push('height'); |
| 78 | + break; |
| 79 | + case 'translateX': values[0].push('width'); break; |
| 80 | + case 'translateY': values[0].push('height'); break; |
| 81 | + case 'translate3d': |
| 82 | + values[0].push('width'); |
| 83 | + values[1].push('height'); |
| 84 | + break; |
| 85 | + } |
| 86 | + } |
| 87 | + |
| 88 | + results.push({ |
| 89 | + name, |
| 90 | + values |
| 91 | + }); |
| 92 | + } |
| 93 | + |
| 94 | + return results; |
| 95 | + } |
| 96 | + |
| 97 | + static value(input) { |
| 98 | + if(!input || !input.length) return null; |
| 99 | + var cardinal = input[2] || 'width'; |
| 100 | + |
| 101 | + if(typeof input === 'string') |
| 102 | + { |
| 103 | + input = input.match(/([+-]?\d+?(?:\.\d+)?)(px|em|rem|ex|%|vw|vh|vmin|vmax|in|cm|mm|pt|pc|deg|rad|turn)?/); |
| 104 | + var value = parseFloat(input[1]); |
| 105 | + var unit = input[2]; |
| 106 | + } |
| 107 | + |
| 108 | + else |
| 109 | + { |
| 110 | + var [value, unit] = input; |
| 111 | + } |
| 112 | + |
| 113 | + switch (unit) { |
| 114 | + case 'em': return value * CSSParser.base.fontSize; |
| 115 | + case 'rem': return value * parseFloat(getComputedStyle(document.documentElement).fontSize); |
| 116 | + case 'ch': return value * CSSParser.base.fontSize * 0.5; |
| 117 | + case 'ex': return value * CSSParser.base.fontSize * 0.45; |
| 118 | + case '%': return value * CSSParser.base[cardinal] / 100; |
| 119 | + case 'vw': return value * window.innerWidth / 100; |
| 120 | + case 'vh': return value * window.innerHeight / 100; |
| 121 | + case 'vmin': return value * Math.min(window.innerWidth, window.innerHeight) / 100; |
| 122 | + case 'vmax': return value * Math.max(window.innerWidth, window.innerHeight) / 100; |
| 123 | + case 'in': return value * 72; |
| 124 | + case 'cm': return value / 2.54 * 72; |
| 125 | + case 'mm': return value / 2.54 * 72 / 10; |
| 126 | + case 'pt': return value * 96 / 72; |
| 127 | + case 'pc': return value * CSSParser.base[cardinal]; |
| 128 | + case 'deg': return value * 0.017453292519943295; |
| 129 | + case 'rad': return value; |
| 130 | + case 'turn': return value * 6.283185307179586; |
| 131 | + default: return value; |
| 132 | + } |
| 133 | + } |
| 134 | +} |
| 135 | + |
| 136 | +CSSParser.base = { width: 1, height: 1, fontSize: 16 }; |
| 137 | + |
| 138 | +export default CSSParser; |
0 commit comments