convertUnit.js 2.67 KB
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;
var conversions = {
  // Absolute length units
  'px': {
    'px': 1,
    'cm': 96 / 2.54,
    'mm': 96 / 25.4,
    'q': 96 / 101.6,
    'in': 96,
    'pt': 96 / 72,
    'pc': 16
  },
  'cm': {
    'px': 2.54 / 96,
    'cm': 1,
    'mm': 0.1,
    'q': 0.025,
    'in': 2.54,
    'pt': 2.54 / 72,
    'pc': 2.54 / 6
  },
  'mm': {
    'px': 25.4 / 96,
    'cm': 10,
    'mm': 1,
    'q': 0.25,
    'in': 25.4,
    'pt': 25.4 / 72,
    'pc': 25.4 / 6
  },
  'q': {
    'px': 101.6 / 96,
    'cm': 40,
    'mm': 4,
    'q': 1,
    'in': 101.6,
    'pt': 101.6 / 72,
    'pc': 101.6 / 6
  },
  'in': {
    'px': 1 / 96,
    'cm': 1 / 2.54,
    'mm': 1 / 25.4,
    'q': 1 / 101.6,
    'in': 1,
    'pt': 1 / 72,
    'pc': 1 / 6
  },
  'pt': {
    'px': 0.75,
    'cm': 72 / 2.54,
    'mm': 72 / 25.4,
    'q': 72 / 101.6,
    'in': 72,
    'pt': 1,
    'pc': 12
  },
  'pc': {
    'px': 0.0625,
    'cm': 6 / 2.54,
    'mm': 6 / 25.4,
    'q': 6 / 101.6,
    'in': 6,
    'pt': 6 / 72,
    'pc': 1
  },
  // Angle units
  'deg': {
    'deg': 1,
    'grad': 0.9,
    'rad': 180 / Math.PI,
    'turn': 360
  },
  'grad': {
    'deg': 400 / 360,
    'grad': 1,
    'rad': 200 / Math.PI,
    'turn': 400
  },
  'rad': {
    'deg': Math.PI / 180,
    'grad': Math.PI / 200,
    'rad': 1,
    'turn': Math.PI * 2
  },
  'turn': {
    'deg': 1 / 360,
    'grad': 0.0025,
    'rad': 0.5 / Math.PI,
    'turn': 1
  },
  // Duration units
  's': {
    's': 1,
    'ms': 0.001
  },
  'ms': {
    's': 1000,
    'ms': 1
  },
  // Frequency units
  'hz': {
    'hz': 1,
    'khz': 1000
  },
  'khz': {
    'hz': 0.001,
    'khz': 1
  },
  // Resolution units
  'dpi': {
    'dpi': 1,
    'dpcm': 1 / 2.54,
    'dppx': 1 / 96
  },
  'dpcm': {
    'dpi': 2.54,
    'dpcm': 1,
    'dppx': 2.54 / 96
  },
  'dppx': {
    'dpi': 96,
    'dpcm': 96 / 2.54,
    'dppx': 1
  }
};

function convertUnit(value, sourceUnit, targetUnit, precision) {
  var sourceUnitNormalized = sourceUnit.toLowerCase();
  var targetUnitNormalized = targetUnit.toLowerCase();

  if (!conversions[targetUnitNormalized]) {
    throw new Error("Cannot convert to " + targetUnit);
  }

  if (!conversions[targetUnitNormalized][sourceUnitNormalized]) {
    throw new Error("Cannot convert from " + sourceUnit + " to " + targetUnit);
  }

  var converted = conversions[targetUnitNormalized][sourceUnitNormalized] * value;

  if (precision !== false) {
    precision = Math.pow(10, parseInt(precision) || 5);
    return Math.round(converted * precision) / precision;
  }

  return converted;
}

var _default = convertUnit;
exports.default = _default;
module.exports = exports.default;