| /** |
| * @license |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| import type { |
| Matcher, |
| RangeSelector, |
| Selector, |
| } from '@apache-annotator/selector'; |
| import { ownerDocument } from '../owner-document'; |
| import { cartesian } from './cartesian'; |
| |
| /** |
| * Find the range(s) corresponding to the given {@link |
| * RangeSelector}. |
| * |
| * As a RangeSelector itself nests two further selectors, one needs to pass a |
| * `createMatcher` function that will be used to process those nested selectors. |
| * |
| * The function is curried, taking first the `createMatcher` function, then the |
| * selector, and then the scope. |
| * |
| * As there may be multiple matches for a given selector, the matcher will |
| * return an (async) generator that produces each match in the order they are |
| * found in the text. If both its nested selectors produce multiple matches, the |
| * RangeSelector matches each possible pair among those in which the order of |
| * start and end are respected. *(Note this behaviour is a rather free |
| * interpretation — the Web Annotation Data Model spec is silent about multiple |
| * matches for RangeSelectors)* |
| * |
| * @example |
| * By using a matcher for {@link TextQuoteSelector}s, one |
| * could create a matcher for text quotes with ellipsis to select a phrase |
| * “ipsum … amet,”: |
| * ``` |
| * const selector = { |
| * type: 'RangeSelector', |
| * startSelector: { |
| * type: 'TextQuoteSelector', |
| * exact: 'ipsum ', |
| * }, |
| * endSelector: { |
| * type: 'TextQuoteSelector', |
| * // Because the end of a RangeSelector is *exclusive*, we will present the |
| * // latter part of the quote as the *prefix* so it will be part of the |
| * // match. |
| * exact: '', |
| * prefix: ' amet,', |
| * } |
| * }; |
| * const createRangeSelectorMatcher = |
| * makeCreateRangeSelectorMatcher(createTextQuoteMatcher); |
| * const match = createRangeSelectorMatcher(selector)(document.body); |
| * console.log(match) |
| * // ⇒ Range { startContainer: #text, startOffset: 6, endContainer: #text, |
| * // endOffset: 27, … } |
| * ``` |
| * |
| * @example |
| * To support RangeSelectors that might themselves contain RangeSelectors, |
| * recursion can be created by supplying the resulting matcher creator function |
| * as the `createMatcher` parameter: |
| * ``` |
| * const createWhicheverMatcher = (selector) => { |
| * const innerCreateMatcher = { |
| * TextQuoteSelector: createTextQuoteSelectorMatcher, |
| * TextPositionSelector: createTextPositionSelectorMatcher, |
| * RangeSelector: makeCreateRangeSelectorMatcher(createWhicheverMatcher), |
| * }[selector.type]; |
| * return innerCreateMatcher(selector); |
| * }); |
| * ``` |
| * |
| * @param createMatcher - The function used to process nested selectors. |
| * @returns A function that, given a RangeSelector, creates a {@link |
| * Matcher} function that applies it to a given {@link https://developer.mozilla.org/en-US/docs/Web/API/Range |
| * | Range} |
| * |
| * @public |
| */ |
| export function makeCreateRangeSelectorMatcher( |
| createMatcher: <T extends Selector>(selector: T) => Matcher<Range, Range>, |
| ): (selector: RangeSelector) => Matcher<Range, Range> { |
| return function createRangeSelectorMatcher(selector) { |
| const startMatcher = createMatcher(selector.startSelector); |
| const endMatcher = createMatcher(selector.endSelector); |
| |
| return async function* matchAll(scope) { |
| const startMatches = startMatcher(scope); |
| const endMatches = endMatcher(scope); |
| |
| const pairs = cartesian(startMatches, endMatches); |
| |
| for await (const [start, end] of pairs) { |
| const result = ownerDocument(scope).createRange(); |
| |
| result.setStart(start.startContainer, start.startOffset); |
| result.setEnd(end.startContainer, end.startOffset); |
| |
| if (!result.collapsed) yield result; |
| } |
| }; |
| }; |
| } |