diff --git a/assets/js/flexsearch.js b/assets/js/flexsearch.js new file mode 100644 index 0000000..7a60872 --- /dev/null +++ b/assets/js/flexsearch.js @@ -0,0 +1,367 @@ +// Search functionality using FlexSearch. + +// Change shortcut key to cmd+k on Mac, iPad or iPhone. +document.addEventListener("DOMContentLoaded", function () { + if (/iPad|iPhone|Macintosh/.test(navigator.userAgent)) { + // select the kbd element under the .search-wrapper class + const keys = document.querySelectorAll(".search-wrapper kbd"); + keys.forEach(key => { + key.innerHTML = '⌘K'; + }); + } +}); + +// Render the search data as JSON. +// {{ $searchDataFile := printf "%s.search-data.json" .Language.Lang }} +// {{ $searchData := resources.Get "json/search-data.json" | resources.ExecuteAsTemplate $searchDataFile . }} +// {{ if hugo.IsProduction }} +// {{ $searchData := $searchData | minify | fingerprint }} +// {{ end }} +// {{ $noResultsFound := (T "noResultsFound") | default "No results found." }} + +(function () { + const searchDataURL = '{{ $searchData.RelPermalink }}'; + + const inputElements = document.querySelectorAll('.search-input'); + for (const el of inputElements) { + el.addEventListener('focus', init); + el.addEventListener('keyup', search); + el.addEventListener('keydown', handleKeyDown); + } + + // Get the search wrapper, input, and results elements. + function getActiveSearchElement() { + const inputs = Array.from(document.querySelectorAll('.search-wrapper')).filter(el => el.clientHeight > 0); + if (inputs.length === 1) { + return { + wrapper: inputs[0], + inputElement: inputs[0].querySelector('.search-input'), + resultsElement: inputs[0].querySelector('.search-results') + }; + } + return undefined; + } + + const INPUTS = ['input', 'select', 'button', 'textarea'] + + // Focus the search input when pressing ctrl+k/cmd+k or /. + document.addEventListener('keydown', function (e) { + const { inputElement } = getActiveSearchElement(); + if (!inputElement) return; + + const activeElement = document.activeElement; + const tagName = activeElement && activeElement.tagName; + if ( + inputElement === activeElement || + !tagName || + INPUTS.includes(tagName) || + (activeElement && activeElement.isContentEditable)) + return; + + if ( + e.key === '/' || + (e.key === 'k' && + (e.metaKey /* for Mac */ || /* for non-Mac */ e.ctrlKey)) + ) { + e.preventDefault(); + inputElement.focus(); + } else if (e.key === 'Escape' && inputElement.value) { + inputElement.blur(); + } + }); + + // Dismiss the search results when clicking outside the search box. + document.addEventListener('mousedown', function (e) { + const { inputElement, resultsElement } = getActiveSearchElement(); + if (!inputElement || !resultsElement) return; + if ( + e.target !== inputElement && + e.target !== resultsElement && + !resultsElement.contains(e.target) + ) { + hideSearchResults(); + } + }); + + // Get the currently active result and its index. + function getActiveResult() { + const { resultsElement } = getActiveSearchElement(); + if (!resultsElement) return { result: undefined, index: -1 }; + + const result = resultsElement.querySelector('.active'); + if (!result) return { result: undefined, index: -1 }; + + const index = parseInt(result.dataset.index, 10); + return { result, index }; + } + + // Set the active result by index. + function setActiveResult(index) { + const { resultsElement } = getActiveSearchElement(); + if (!resultsElement) return; + + const { result: activeResult } = getActiveResult(); + activeResult && activeResult.classList.remove('active'); + const result = resultsElement.querySelector(`[data-index="${index}"]`); + if (result) { + result.classList.add('active'); + result.focus(); + } + } + + // Get the number of search results from the DOM. + function getResultsLength() { + const { resultsElement } = getActiveSearchElement(); + if (!resultsElement) return 0; + return resultsElement.dataset.count; + } + + // Finish the search by hiding the results and clearing the input. + function finishSearch() { + const { inputElement } = getActiveSearchElement(); + if (!inputElement) return; + hideSearchResults(); + inputElement.value = ''; + inputElement.blur(); + } + + function hideSearchResults() { + const { resultsElement } = getActiveSearchElement(); + if (!resultsElement) return; + resultsElement.classList.add('hidden'); + } + + // Handle keyboard events. + function handleKeyDown(e) { + const { inputElement } = getActiveSearchElement(); + if (!inputElement) return; + + const resultsLength = getResultsLength(); + const { result: activeResult, index: activeIndex } = getActiveResult(); + + switch (e.key) { + case 'ArrowUp': + e.preventDefault(); + if (activeIndex > 0) setActiveResult(activeIndex - 1); + break; + case 'ArrowDown': + e.preventDefault(); + if (activeIndex + 1 < resultsLength) setActiveResult(activeIndex + 1); + break; + case 'Enter': + e.preventDefault(); + if (activeResult) { + activeResult.click(); + } + finishSearch(); + case 'Escape': + e.preventDefault(); + hideSearchResults(); + inputElement.blur(); + break; + } + } + + // Initializes the search. + function init(e) { + e.target.removeEventListener('focus', init); + if (!(window.pageIndex && window.sectionIndex)) { + preloadIndex(); + } + } + + // Preload the search index. + async function preloadIndex() { + window.pageIndex = new FlexSearch.Document({ + tokenize: 'full', + cache: 100, + document: { + id: 'id', + store: ['title'], + index: "content" + } + }); + + window.sectionIndex = new FlexSearch.Document({ + tokenize: 'full', + cache: 100, + document: { + id: 'id', + store: ['title', 'content', 'url', 'display'], + index: "content", + tag: 'pageId' + } + }); + + const resp = await fetch(searchDataURL); + const data = await resp.json(); + let pageId = 0; + for (const route in data) { + let pageContent = ''; + ++pageId; + + for (const heading in data[route].data) { + const [hash, text] = heading.split('#'); + const url = route.trimEnd('/') + (hash ? '#' + hash : ''); + const title = text || data[route].title; + + const content = data[route].data[heading] || ''; + const paragraphs = content.split('\n').filter(Boolean); + + sectionIndex.add({ + id: url, + url, + title, + pageId: `page_${pageId}`, + content: title, + ...(paragraphs[0] && { display: paragraphs[0] }) + }); + + for (let i = 0; i < paragraphs.length; i++) { + sectionIndex.add({ + id: `${url}_${i}`, + url, + title, + pageId: `page_${pageId}`, + content: paragraphs[i] + }); + } + + pageContent += ` ${title} ${content}`; + } + + window.pageIndex.add({ + id: pageId, + title: data[route].title, + content: pageContent + }); + + } + } + + function search(e) { + const query = e.target.value; + if (!e.target.value) { + hideSearchResults(); + return; + } + + const { resultsElement } = getActiveSearchElement(); + while (resultsElement.firstChild) { + resultsElement.removeChild(resultsElement.firstChild); + } + resultsElement.classList.remove('hidden'); + + const pageResults = window.pageIndex.search(query, 5, { enrich: true, suggest: true })[0]?.result || []; + + const results = []; + const pageTitleMatches = {}; + + for (let i = 0; i < pageResults.length; i++) { + const result = pageResults[i]; + pageTitleMatches[i] = 0; + + // Show the top 5 results for each page + const sectionResults = window.sectionIndex.search(query, 5, { enrich: true, suggest: true, tag: `page_${result.id}` })[0]?.result || []; + let isFirstItemOfPage = true + const occurred = {} + + for (let j = 0; j < sectionResults.length; j++) { + const { doc } = sectionResults[j] + const isMatchingTitle = doc.display !== undefined + if (isMatchingTitle) { + pageTitleMatches[i]++ + } + const { url, title } = doc + const content = doc.display || doc.content + + if (occurred[url + '@' + content]) continue + occurred[url + '@' + content] = true + results.push({ + _page_rk: i, + _section_rk: j, + route: url, + prefix: isFirstItemOfPage ? result.doc.title : undefined, + children: { title, content } + }) + isFirstItemOfPage = false + } + } + const sortedResults = results + .sort((a, b) => { + // Sort by number of matches in the title. + if (a._page_rk === b._page_rk) { + return a._section_rk - b._section_rk + } + if (pageTitleMatches[a._page_rk] !== pageTitleMatches[b._page_rk]) { + return pageTitleMatches[b._page_rk] - pageTitleMatches[a._page_rk] + } + return a._page_rk - b._page_rk + }) + .map(res => ({ + id: `${res._page_rk}_${res._section_rk}`, + route: res.route, + prefix: res.prefix, + children: res.children + })); + displayResults(sortedResults, query); + } + + function displayResults(results, query) { + const { resultsElement } = getActiveSearchElement(); + if (!resultsElement) return; + + if (!results.length) { + resultsElement.innerHTML = `{{ $noResultsFound | safeHTML }}`; + return; + } + + // Highlight the query in the result text. + function highlightMatches(text, query) { + const escapedQuery = query.replace(/[-\\^$*+?.()|[\]{}]/g, '\\$&'); + const regex = new RegExp(escapedQuery, 'gi'); + return text.replace(regex, (match) => `${match}`); + } + + // Create a DOM element from the HTML string. + function createElement(str) { + const div = document.createElement('div'); + div.innerHTML = str.trim(); + return div.firstChild; + } + + function handleMouseMove(e) { + const target = e.target.closest('a'); + if (target) { + const active = resultsElement.querySelector('a.active'); + if (active) { + active.classList.remove('active'); + } + target.classList.add('active'); + } + } + + const fragment = document.createDocumentFragment(); + for (let i = 0; i < results.length; i++) { + const result = results[i]; + if (result.prefix) { + fragment.appendChild(createElement(` +