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"use strict";
Object.defineProperty(exports, "__esModule", {
    value: true
});
function _export(target, all) {
    for(var name in all)Object.defineProperty(target, name, {
        enumerable: true,
        get: all[name]
    });
}
_export(exports, {
    hasMathFn: function() {
        return hasMathFn;
    },
    addWhitespaceAroundMathOperators: function() {
        return addWhitespaceAroundMathOperators;
    }
});
const LOWER_A = 0x61;
const LOWER_Z = 0x7a;
const UPPER_A = 0x41;
const UPPER_Z = 0x5a;
const LOWER_E = 0x65;
const UPPER_E = 0x45;
const ZERO = 0x30;
const NINE = 0x39;
const ADD = 0x2b;
const SUB = 0x2d;
const MUL = 0x2a;
const DIV = 0x2f;
const OPEN_PAREN = 0x28;
const CLOSE_PAREN = 0x29;
const COMMA = 0x2c;
const SPACE = 0x20;
const PERCENT = 0x25;
const MATH_FUNCTIONS = [
    "calc",
    "min",
    "max",
    "clamp",
    "mod",
    "rem",
    "sin",
    "cos",
    "tan",
    "asin",
    "acos",
    "atan",
    "atan2",
    "pow",
    "sqrt",
    "hypot",
    "log",
    "exp",
    "round"
];
function hasMathFn(input) {
    return input.indexOf("(") !== -1 && MATH_FUNCTIONS.some((fn)=>input.includes(`${fn}(`));
}
function addWhitespaceAroundMathOperators(input) {
    // Bail early if there are no math functions in the input
    if (!MATH_FUNCTIONS.some((fn)=>input.includes(fn))) {
        return input;
    }
    let result = "";
    let formattable = [];
    let valuePos = null;
    let lastValuePos = null;
    for(let i = 0; i < input.length; i++){
        let char = input.charCodeAt(i);
        // Track if we see a number followed by a unit, then we know for sure that
        // this is not a function call.
        if (char >= ZERO && char <= NINE) {
            valuePos = i;
        } else if (valuePos !== null && (char === PERCENT || char >= LOWER_A && char <= LOWER_Z || char >= UPPER_A && char <= UPPER_Z)) {
            valuePos = i;
        } else {
            lastValuePos = valuePos;
            valuePos = null;
        }
        // Determine if we're inside a math function
        if (char === OPEN_PAREN) {
            result += input[i];
            // Scan backwards to determine the function name. This assumes math
            // functions are named with lowercase alphanumeric characters.
            let start = i;
            for(let j = i - 1; j >= 0; j--){
                let inner = input.charCodeAt(j);
                if (inner >= ZERO && inner <= NINE) {
                    start = j // 0-9
                    ;
                } else if (inner >= LOWER_A && inner <= LOWER_Z) {
                    start = j // a-z
                    ;
                } else {
                    break;
                }
            }
            let fn = input.slice(start, i);
            // This is a known math function so start formatting
            if (MATH_FUNCTIONS.includes(fn)) {
                formattable.unshift(true);
                continue;
            } else if (formattable[0] && fn === "") {
                formattable.unshift(true);
                continue;
            }
            // This is not a known math function so don't format it
            formattable.unshift(false);
            continue;
        } else if (char === CLOSE_PAREN) {
            result += input[i];
            formattable.shift();
        } else if (char === COMMA && formattable[0]) {
            result += `, `;
            continue;
        } else if (char === SPACE && formattable[0] && result.charCodeAt(result.length - 1) === SPACE) {
            continue;
        } else if ((char === ADD || char === MUL || char === DIV || char === SUB) && formattable[0]) {
            let trimmed = result.trimEnd();
            let prev = trimmed.charCodeAt(trimmed.length - 1);
            let prevPrev = trimmed.charCodeAt(trimmed.length - 2);
            let next = input.charCodeAt(i + 1);
            // Do not add spaces for scientific notation, e.g.: `-3.4e-2`
            if ((prev === LOWER_E || prev === UPPER_E) && prevPrev >= ZERO && prevPrev <= NINE) {
                result += input[i];
                continue;
            } else if (prev === ADD || prev === MUL || prev === DIV || prev === SUB) {
                result += input[i];
                continue;
            } else if (prev === OPEN_PAREN || prev === COMMA) {
                result += input[i];
                continue;
            } else if (input.charCodeAt(i - 1) === SPACE) {
                result += `${input[i]} `;
            } else if (// Previous is a digit
            prev >= ZERO && prev <= NINE || // Next is a digit
            next >= ZERO && next <= NINE || // Previous is end of a function call (or parenthesized expression)
            prev === CLOSE_PAREN || // Next is start of a parenthesized expression
            next === OPEN_PAREN || // Next is an operator
            next === ADD || next === MUL || next === DIV || next === SUB || // Previous position was a value (+ unit)
            lastValuePos !== null && lastValuePos === i - 1) {
                result += ` ${input[i]} `;
            } else {
                result += input[i];
            }
        } else {
            result += input[i];
        }
    }
    return result;
}