Syllabus/themes/piratecare/node_modules/reduce-css-calc/dist/lib/reducer.js

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2020-03-05 04:10:52 +00:00
'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.flip = flip;
var _convert = require('./convert');
var _convert2 = _interopRequireDefault(_convert);
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
function reduce(node, precision) {
if (node.type === "MathExpression") return reduceMathExpression(node, precision);
return node;
}
function isEqual(left, right) {
return left.type === right.type && left.value === right.value;
}
function isValueType(type) {
switch (type) {
case 'LengthValue':
case 'AngleValue':
case 'TimeValue':
case 'FrequencyValue':
case 'ResolutionValue':
case 'EmValue':
case 'ExValue':
case 'ChValue':
case 'RemValue':
case 'VhValue':
case 'VwValue':
case 'VminValue':
case 'VmaxValue':
case 'PercentageValue':
case 'Value':
return true;
}
return false;
}
function convertMathExpression(node, precision) {
var nodes = (0, _convert2.default)(node.left, node.right, precision);
var left = reduce(nodes.left, precision);
var right = reduce(nodes.right, precision);
if (left.type === "MathExpression" && right.type === "MathExpression") {
if (left.operator === '/' && right.operator === '*' || left.operator === '-' && right.operator === '+' || left.operator === '*' && right.operator === '/' || left.operator === '+' && right.operator === '-') {
if (isEqual(left.right, right.right)) nodes = (0, _convert2.default)(left.left, right.left, precision);else if (isEqual(left.right, right.left)) nodes = (0, _convert2.default)(left.left, right.right, precision);
left = reduce(nodes.left, precision);
right = reduce(nodes.right, precision);
}
}
node.left = left;
node.right = right;
return node;
}
function flip(operator) {
return operator === '+' ? '-' : '+';
}
function flipValue(node) {
if (isValueType(node.type)) node.value = -node.value;else if (node.type == 'MathExpression') {
node.left = flipValue(node.left);
node.right = flipValue(node.right);
}
return node;
}
function reduceAddSubExpression(node, precision) {
var _node = node,
left = _node.left,
right = _node.right,
op = _node.operator;
if (left.type === 'CssVariable' || right.type === 'CssVariable') return node;
// something + 0 => something
// something - 0 => something
if (right.value === 0) return left;
// 0 + something => something
if (left.value === 0 && op === "+") return right;
// 0 - something => -something
if (left.value === 0 && op === "-") return flipValue(right);
// value + value
// value - value
if (left.type === right.type && isValueType(left.type)) {
node = Object.assign({}, left);
if (op === "+") node.value = left.value + right.value;else node.value = left.value - right.value;
}
// value <op> (expr)
if (isValueType(left.type) && (right.operator === '+' || right.operator === '-') && right.type === 'MathExpression') {
// value + (value + something) => (value + value) + something
// value + (value - something) => (value + value) - something
// value - (value + something) => (value - value) - something
// value - (value - something) => (value - value) + something
if (left.type === right.left.type) {
node = Object.assign({}, node);
node.left = reduce({
type: 'MathExpression',
operator: op,
left: left,
right: right.left
}, precision);
node.right = right.right;
node.operator = op === '-' ? flip(right.operator) : right.operator;
return reduce(node, precision);
}
// value + (something + value) => (value + value) + something
// value + (something - value) => (value - value) + something
// value - (something + value) => (value - value) - something
// value - (something - value) => (value + value) - something
else if (left.type === right.right.type) {
node = Object.assign({}, node);
node.left = reduce({
type: 'MathExpression',
operator: op === '-' ? flip(right.operator) : right.operator,
left: left,
right: right.right
}, precision);
node.right = right.left;
return reduce(node, precision);
}
}
// (expr) <op> value
if (left.type === 'MathExpression' && (left.operator === '+' || left.operator === '-') && isValueType(right.type)) {
// (value + something) + value => (value + value) + something
// (value - something) + value => (value + value) - something
// (value + something) - value => (value - value) + something
// (value - something) - value => (value - value) - something
if (right.type === left.left.type) {
node = Object.assign({}, left);
node.left = reduce({
type: 'MathExpression',
operator: op,
left: left.left,
right: right
}, precision);
return reduce(node, precision);
}
// (something + value) + value => something + (value + value)
// (something - value1) + value2 => something - (value2 - value1)
// (something + value) - value => something + (value - value)
// (something - value) - value => something - (value + value)
else if (right.type === left.right.type) {
node = Object.assign({}, left);
if (left.operator === '-') {
node.right = reduce({
type: 'MathExpression',
operator: op === '-' ? '+' : '-',
left: right,
right: left.right
}, precision);
node.operator = op === '-' ? '-' : '+';
} else {
node.right = reduce({
type: 'MathExpression',
operator: op,
left: left.right,
right: right
}, precision);
}
if (node.right.value < 0) {
node.right.value *= -1;
node.operator = node.operator === '-' ? '+' : '-';
}
return reduce(node, precision);
}
}
return node;
}
function reduceDivisionExpression(node, precision) {
if (!isValueType(node.right.type)) return node;
if (node.right.type !== 'Value') throw new Error('Cannot divide by "' + node.right.unit + '", number expected');
if (node.right.value === 0) throw new Error('Cannot divide by zero');
// (expr) / value
if (node.left.type === 'MathExpression') {
if (isValueType(node.left.left.type) && isValueType(node.left.right.type)) {
node.left.left.value /= node.right.value;
node.left.right.value /= node.right.value;
return reduce(node.left, precision);
}
return node;
}
// something / value
else if (isValueType(node.left.type)) {
node.left.value /= node.right.value;
return node.left;
}
return node;
}
function reduceMultiplicationExpression(node) {
// (expr) * value
if (node.left.type === 'MathExpression' && node.right.type === 'Value') {
if (isValueType(node.left.left.type) && isValueType(node.left.right.type)) {
node.left.left.value *= node.right.value;
node.left.right.value *= node.right.value;
return node.left;
}
}
// something * value
else if (isValueType(node.left.type) && node.right.type === 'Value') {
node.left.value *= node.right.value;
return node.left;
}
// value * (expr)
else if (node.left.type === 'Value' && node.right.type === 'MathExpression') {
if (isValueType(node.right.left.type) && isValueType(node.right.right.type)) {
node.right.left.value *= node.left.value;
node.right.right.value *= node.left.value;
return node.right;
}
}
// value * something
else if (node.left.type === 'Value' && isValueType(node.right.type)) {
node.right.value *= node.left.value;
return node.right;
}
return node;
}
function reduceMathExpression(node, precision) {
node = convertMathExpression(node, precision);
switch (node.operator) {
case "+":
case "-":
return reduceAddSubExpression(node, precision);
case "/":
return reduceDivisionExpression(node, precision);
case "*":
return reduceMultiplicationExpression(node);
}
return node;
}
exports.default = reduce;