element-web/src/autocomplete/QueryMatcher.js

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JavaScript
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2017-02-10 17:04:52 +00:00
//@flow
import _at from 'lodash/at';
import _flatMap from 'lodash/flatMap';
import _sortBy from 'lodash/sortBy';
import _sortedUniq from 'lodash/sortedUniq';
import _keys from 'lodash/keys';
class KeyMap {
keys: Array<String>;
objectMap: {[String]: Array<Object>};
priorityMap = new Map();
}
export default class QueryMatcher {
/**
* Given an array of objects and keys, returns a KeyMap
* Keys can refer to object properties by name and as in JavaScript (for nested properties)
*
* To use, simply presort objects by required criteria, run through this function and create a QueryMatcher with the
* resulting KeyMap.
*
* TODO: Handle arrays and objects (Fuse did this, RoomProvider uses it)
*/
static valuesToKeyMap(objects: Array<Object>, keys: Array<String>): KeyMap {
const keyMap = new KeyMap();
const map = {};
objects.forEach((object, i) => {
const keyValues = _at(object, keys);
for (const keyValue of keyValues) {
if (!map.hasOwnProperty(keyValue)) {
map[keyValue] = [];
}
map[keyValue].push(object);
}
keyMap.priorityMap.set(object, i);
});
keyMap.objectMap = map;
keyMap.keys = _keys(map);
return keyMap;
}
constructor(objects: Array<Object>, options: {[Object]: Object} = {}) {
this.options = options;
this.keys = options.keys;
this.setObjects(objects);
}
setObjects(objects: Array<Object>) {
this.keyMap = QueryMatcher.valuesToKeyMap(objects, this.keys);
}
match(query: String): Array<Object> {
query = query.toLowerCase().replace(/[^\w]/g, '');
const results = _sortedUniq(_sortBy(_flatMap(this.keyMap.keys, (key) => {
return key.toLowerCase().replace(/[^\w]/g, '').indexOf(query) >= 0 ? this.keyMap.objectMap[key] : [];
}), (candidate) => this.keyMap.priorityMap.get(candidate)));
return results;
}
}