Cite/sort.js

  1. import {getLabel} from '../get/modules/label'
  2. import getName from '../get/name'
  4. /**
  5.  * @callback Cite~sort
  6.  * @param {CSL} a - element a
  7.  * @param {CSL} b - element b
  8.  * @return {Number} positive for a > b, negative for b > a, zero for a = b
  9.  */
  11. /**
  12.  * Get value for comparing
  13.  *
  14.  * @access private
  15.  * @method getComparisonValue
  16.  *
  17.  * @param {CSL} obj - obj
  18.  * @param {String} prop - The prop in question
  19.  * @param {Boolean} label - Prop is label
  20.  *
  21.  * @return {String|Number} something to compare
  22.  */
  23. const getComparisonValue = function (obj, prop, label = prop === 'label') {
  24.   let value = label ? getLabel(obj) : obj[prop]
  26.   switch (prop) {
  27.     case 'author':
  28.     case 'editor':
  29.       return value.map(name => name.literal || name.family || getName(name))
  31.     case 'accessed':
  32.     case 'issued':
  33.       return value['date-parts'][0]
  35.     case 'page':
  36.       return value.split('-').map(num => parseInt(num))
  38.     case 'edition':
  39.     case 'issue':
  40.     case 'volume':
  41.       value = parseInt(value)
  42.       return !isNaN(value) ? value : -Infinity
  44.     default:
  45.       return value || -Infinity
  46.   }
  47. }
  49. /**
  50.  * Compares props
  51.  *
  52.  * @access private
  53.  * @method compareProp
  54.  *
  55.  * @param {CSL} a - Object a
  56.  * @param {CSL} b - Object b
  57.  * @param {String} prop - The prop in question. Prepend ! to sort the other way around.
  58.  * @param {Boolean} flip - Override flip
  59.  *
  60.  * @return {Number} positive for a > b, negative for b > a, zero for a = b (flips if prop has !)
  61.  */
  62. const compareProp = function (a, b, prop, flip = /^!/.test(prop)) {
  63.   prop = prop.replace(/^!/, '')
  64.   const valueA = getComparisonValue(a, prop)
  65.   const valueB = getComparisonValue(b, prop)
  67.   return valueA === valueB ? 0 : flip !== (valueA > valueB) ? 1 : -1
  68. }
  70. /**
  71.  * Generates a sorting callback based on props.
  72.  *
  73.  * @access private
  74.  * @method getSortCallback
  75.  *
  76.  * @param {...String} props - How to sort
  77.  *
  78.  * @return {Cite~sort} sorting callback
  79.  */
  80. const getSortCallback = function (...props) {
  81.   return (a, b) => {
  82.     const keys = props.slice()
  83.     let output = 0
  85.     while (!output && keys.length) {
  86.       output = compareProp(a, b, keys.shift())
  87.     }
  89.     return output
  90.   }
  91. }
  93. /**
  94.  * Sort the dataset
  95.  *
  96.  * @memberof Cite#
  97.  *
  98.  * @param {Cite~sort|Array<String>} [method=[]] - How to sort
  99.  * @param {Boolean} [log=false] - Show this call in the log
  100.  *
  101.  * @return {Cite} The updated parent object
  102.  */
  103. const sort = function (method = [], log) {
  104.   if (log) {
  105.     this.save()
  106.   }
  108.   this.data.sort(typeof method === 'function' ? method : getSortCallback(...method, 'label'))
  110.   return this
  111. }
  113. export { sort }