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const feature_unit = {
|
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|
'width': 'px',
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|
'height': 'px',
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|
'device-width': 'px',
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|
'device-height': 'px',
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|
'aspect-ratio': '',
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|
'device-aspect-ratio': '',
|
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|
'color': '',
|
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|
'color-index': '',
|
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|
'monochrome': '',
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|
'resolution': 'dpi'
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|
};
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|
|
|
|
// Supported min-/max- attributes
|
|
|
const feature_name = Object.keys(feature_unit);
|
|
|
|
|
|
const step = .001; // smallest even number that won’t break complex queries (1in = 96px)
|
|
|
|
|
|
const power = {
|
|
|
'>': 1,
|
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|
'<': -1
|
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|
};
|
|
|
|
|
|
const minmax = {
|
|
|
'>': 'min',
|
|
|
'<': 'max'
|
|
|
};
|
|
|
|
|
|
function create_query(name, gtlt, eq, value) {
|
|
|
return value.replace(/([-\d\.]+)(.*)/, function (_match, number, unit) {
|
|
|
const initialNumber = parseFloat(number);
|
|
|
|
|
|
if (parseFloat(number) || eq) {
|
|
|
// if eq is true, then number remains same
|
|
|
if (!eq) {
|
|
|
// change integer pixels value only on integer pixel
|
|
|
if (unit === 'px' && initialNumber === parseInt(number, 10)) {
|
|
|
number = initialNumber + power[gtlt];
|
|
|
} else {
|
|
|
number = Number(Math.round(parseFloat(number) + step * power[gtlt] + 'e6')+'e-6');
|
|
|
}
|
|
|
}
|
|
|
} else {
|
|
|
number = power[gtlt] + feature_unit[name];
|
|
|
}
|
|
|
|
|
|
return '(' + minmax[gtlt] + '-' + name + ': ' + number + unit + ')';
|
|
|
});
|
|
|
}
|
|
|
|
|
|
function transform(rule) {
|
|
|
/**
|
|
|
* 转换 <mf-name> <|>= <mf-value>
|
|
|
* $1 $2 $3
|
|
|
* (width >= 300px) => (min-width: 300px)
|
|
|
* (width <= 900px) => (max-width: 900px)
|
|
|
*/
|
|
|
|
|
|
if (!rule.params.includes('<') && !rule.params.includes('>')) {
|
|
|
return
|
|
|
}
|
|
|
|
|
|
// The value doesn't support negative values
|
|
|
// But -0 is always equivalent to 0 in CSS, and so is also accepted as a valid <mq-boolean> value.
|
|
|
|
|
|
rule.params = rule.params.replace(/\(\s*([a-z-]+?)\s*([<>])(=?)\s*((?:-?\d*\.?(?:\s*\/?\s*)?\d+[a-z]*)?)\s*\)/gi, function($0, $1, $2, $3, $4) {
|
|
|
if (feature_name.indexOf($1) > -1) {
|
|
|
return create_query($1, $2, $3, $4);
|
|
|
}
|
|
|
// If it is not the specified attribute, don't replace
|
|
|
return $0;
|
|
|
})
|
|
|
|
|
|
/**
|
|
|
* 转换 <mf-value> <|<= <mf-name> <|<= <mf-value>
|
|
|
* 转换 <mf-value> >|>= <mf-name> >|>= <mf-value>
|
|
|
* $1 $2$3 $4 $5$6 $7
|
|
|
* (500px <= width <= 1200px) => (min-width: 500px) and (max-width: 1200px)
|
|
|
* (500px < width <= 1200px) => (min-width: 501px) and (max-width: 1200px)
|
|
|
* (900px >= width >= 300px) => (min-width: 300px) and (max-width: 900px)
|
|
|
*/
|
|
|
|
|
|
rule.params = rule.params.replace(/\(\s*((?:-?\d*\.?(?:\s*\/?\s*)?\d+[a-z]*)?)\s*(<|>)(=?)\s*([a-z-]+)\s*(<|>)(=?)\s*((?:-?\d*\.?(?:\s*\/?\s*)?\d+[a-z]*)?)\s*\)/gi, function($0, $1, $2, $3, $4, $5, $6, $7) {
|
|
|
|
|
|
if (feature_name.indexOf($4) > -1) {
|
|
|
if ($2 === '<' && $5 === '<' || $2 === '>' && $5 === '>') {
|
|
|
const min = ($2 === '<') ? $1 : $7;
|
|
|
const max = ($2 === '<') ? $7 : $1;
|
|
|
|
|
|
// output differently depended on expression direction
|
|
|
// <mf-value> <|<= <mf-name> <|<= <mf-value>
|
|
|
// or
|
|
|
// <mf-value> >|>= <mf-name> >|>= <mf-value>
|
|
|
let equals_for_min = $3;
|
|
|
let equals_for_max = $6;
|
|
|
|
|
|
if ($2 === '>') {
|
|
|
equals_for_min = $6;
|
|
|
equals_for_max = $3;
|
|
|
}
|
|
|
|
|
|
return create_query($4, '>', equals_for_min, min) + ' and ' + create_query($4, '<', equals_for_max, max);
|
|
|
}
|
|
|
}
|
|
|
// If it is not the specified attribute, don't replace
|
|
|
return $0;
|
|
|
});
|
|
|
}
|
|
|
|
|
|
module.exports = () => ({
|
|
|
postcssPlugin: 'postcss-media-minmax',
|
|
|
AtRule: {
|
|
|
media: (atRule) => {
|
|
|
transform(atRule);
|
|
|
},
|
|
|
'custom-media': (atRule) => {
|
|
|
transform(atRule);
|
|
|
},
|
|
|
},
|
|
|
});
|
|
|
|
|
|
module.exports.postcss = true
|
