JasonsGong.github.io/js/search/local-search.js
2023-09-22 21:57:28 +08:00

361 lines
12 KiB
JavaScript

/**
* Refer to hexo-generator-searchdb
* https://github.com/next-theme/hexo-generator-searchdb/blob/main/dist/search.js
* Modified by hexo-theme-butterfly
*/
class LocalSearch {
constructor ({
path = '',
unescape = false,
top_n_per_article = 1
}) {
this.path = path
this.unescape = unescape
this.top_n_per_article = top_n_per_article
this.isfetched = false
this.datas = null
}
getIndexByWord (words, text, caseSensitive = false) {
const index = []
const included = new Set()
if (!caseSensitive) {
text = text.toLowerCase()
}
words.forEach(word => {
if (this.unescape) {
const div = document.createElement('div')
div.innerText = word
word = div.innerHTML
}
const wordLen = word.length
if (wordLen === 0) return
let startPosition = 0
let position = -1
if (!caseSensitive) {
word = word.toLowerCase()
}
while ((position = text.indexOf(word, startPosition)) > -1) {
index.push({ position, word })
included.add(word)
startPosition = position + wordLen
}
})
// Sort index by position of keyword
index.sort((left, right) => {
if (left.position !== right.position) {
return left.position - right.position
}
return right.word.length - left.word.length
})
return [index, included]
}
// Merge hits into slices
mergeIntoSlice (start, end, index) {
let item = index[0]
let { position, word } = item
const hits = []
const count = new Set()
while (position + word.length <= end && index.length !== 0) {
count.add(word)
hits.push({
position,
length: word.length
})
const wordEnd = position + word.length
// Move to next position of hit
index.shift()
while (index.length !== 0) {
item = index[0]
position = item.position
word = item.word
if (wordEnd > position) {
index.shift()
} else {
break
}
}
}
return {
hits,
start,
end,
count: count.size
}
}
// Highlight title and content
highlightKeyword (val, slice) {
let result = ''
let index = slice.start
for (const { position, length } of slice.hits) {
result += val.substring(index, position)
index = position + length
result += `<mark class="search-keyword">${val.substr(position, length)}</mark>`
}
result += val.substring(index, slice.end)
return result
}
getResultItems (keywords) {
const resultItems = []
this.datas.forEach(({ title, content, url }) => {
// The number of different keywords included in the article.
const [indexOfTitle, keysOfTitle] = this.getIndexByWord(keywords, title)
const [indexOfContent, keysOfContent] = this.getIndexByWord(keywords, content)
const includedCount = new Set([...keysOfTitle, ...keysOfContent]).size
// Show search results
const hitCount = indexOfTitle.length + indexOfContent.length
if (hitCount === 0) return
const slicesOfTitle = []
if (indexOfTitle.length !== 0) {
slicesOfTitle.push(this.mergeIntoSlice(0, title.length, indexOfTitle))
}
let slicesOfContent = []
while (indexOfContent.length !== 0) {
const item = indexOfContent[0]
const { position } = item
// Cut out 120 characters. The maxlength of .search-input is 80.
const start = Math.max(0, position - 20)
const end = Math.min(content.length, position + 100)
slicesOfContent.push(this.mergeIntoSlice(start, end, indexOfContent))
}
// Sort slices in content by included keywords' count and hits' count
slicesOfContent.sort((left, right) => {
if (left.count !== right.count) {
return right.count - left.count
} else if (left.hits.length !== right.hits.length) {
return right.hits.length - left.hits.length
}
return left.start - right.start
})
// Select top N slices in content
const upperBound = parseInt(this.top_n_per_article, 10)
if (upperBound >= 0) {
slicesOfContent = slicesOfContent.slice(0, upperBound)
}
let resultItem = ''
url = new URL(url, location.origin)
url.searchParams.append('highlight', keywords.join(' '))
if (slicesOfTitle.length !== 0) {
resultItem += `<div class="local-search-hit-item"><a href="${url.href}"><span class="search-result-title">${this.highlightKeyword(title, slicesOfTitle[0])}</span>`
} else {
resultItem += `<div class="local-search-hit-item"><a href="${url.href}"><span class="search-result-title">${title}</span>`
}
slicesOfContent.forEach(slice => {
resultItem += `<p class="search-result">${this.highlightKeyword(content, slice)}...</p></a>`
})
resultItem += '</div>'
resultItems.push({
item: resultItem,
id: resultItems.length,
hitCount,
includedCount
})
})
return resultItems
}
fetchData () {
const isXml = !this.path.endsWith('json')
fetch(this.path)
.then(response => response.text())
.then(res => {
// Get the contents from search data
this.isfetched = true
this.datas = isXml
? [...new DOMParser().parseFromString(res, 'text/xml').querySelectorAll('entry')].map(element => ({
title: element.querySelector('title').textContent,
content: element.querySelector('content').textContent,
url: element.querySelector('url').textContent
}))
: JSON.parse(res)
// Only match articles with non-empty titles
this.datas = this.datas.filter(data => data.title).map(data => {
data.title = data.title.trim()
data.content = data.content ? data.content.trim().replace(/<[^>]+>/g, '') : ''
data.url = decodeURIComponent(data.url).replace(/\/{2,}/g, '/')
return data
})
// Remove loading animation
window.dispatchEvent(new Event('search:loaded'))
})
}
// Highlight by wrapping node in mark elements with the given class name
highlightText (node, slice, className) {
const val = node.nodeValue
let index = slice.start
const children = []
for (const { position, length } of slice.hits) {
const text = document.createTextNode(val.substring(index, position))
index = position + length
const mark = document.createElement('mark')
mark.className = className
mark.appendChild(document.createTextNode(val.substr(position, length)))
children.push(text, mark)
}
node.nodeValue = val.substring(index, slice.end)
children.forEach(element => {
node.parentNode.insertBefore(element, node)
})
}
// Highlight the search words provided in the url in the text
highlightSearchWords (body) {
const params = new URL(location.href).searchParams.get('highlight')
const keywords = params ? params.split(' ') : []
if (!keywords.length || !body) return
const walk = document.createTreeWalker(body, NodeFilter.SHOW_TEXT, null)
const allNodes = []
while (walk.nextNode()) {
if (!walk.currentNode.parentNode.matches('button, select, textarea, .mermaid')) allNodes.push(walk.currentNode)
}
allNodes.forEach(node => {
const [indexOfNode] = this.getIndexByWord(keywords, node.nodeValue)
if (!indexOfNode.length) return
const slice = this.mergeIntoSlice(0, node.nodeValue.length, indexOfNode)
this.highlightText(node, slice, 'search-keyword')
})
}
}
window.addEventListener('load', () => {
// Search
const { path, top_n_per_article, unescape, languages } = GLOBAL_CONFIG.localSearch
const localSearch = new LocalSearch({
path,
top_n_per_article,
unescape
})
const input = document.querySelector('#local-search-input input')
const statsItem = document.getElementById('local-search-stats-wrap')
const $loadingStatus = document.getElementById('loading-status')
const inputEventFunction = () => {
if (!localSearch.isfetched) return
const searchText = input.value.trim().toLowerCase()
if (searchText !== '') $loadingStatus.innerHTML = '<i class="fas fa-spinner fa-pulse"></i>'
const keywords = searchText.split(/[-\s]+/)
const container = document.getElementById('local-search-results')
let resultItems = []
if (searchText.length > 0) {
// Perform local searching
resultItems = localSearch.getResultItems(keywords)
}
if (keywords.length === 1 && keywords[0] === '') {
container.classList.add('no-result')
container.textContent = ''
} else if (resultItems.length === 0) {
container.textContent = ''
statsItem.innerHTML = `<div class="search-result-stats">${languages.hits_empty.replace(/\$\{query}/, searchText)}</div>`
} else {
resultItems.sort((left, right) => {
if (left.includedCount !== right.includedCount) {
return right.includedCount - left.includedCount
} else if (left.hitCount !== right.hitCount) {
return right.hitCount - left.hitCount
}
return right.id - left.id
})
const stats = languages.hits_stats.replace(/\$\{hits}/, resultItems.length)
container.classList.remove('no-result')
container.innerHTML = `<div class="search-result-list">${resultItems.map(result => result.item).join('')}</div>`
statsItem.innerHTML = `<br><div class="search-result-stats">${stats}</div>`
window.pjax && window.pjax.refresh(container)
}
$loadingStatus.textContent = ''
}
let loadFlag = false
const $searchMask = document.getElementById('search-mask')
const $searchDialog = document.querySelector('#local-search .search-dialog')
// fix safari
const fixSafariHeight = () => {
if (window.innerWidth < 768) {
$searchDialog.style.setProperty('--search-height', window.innerHeight + 'px')
}
}
const openSearch = () => {
const bodyStyle = document.body.style
bodyStyle.width = '100%'
bodyStyle.overflow = 'hidden'
btf.animateIn($searchMask, 'to_show 0.5s')
btf.animateIn($searchDialog, 'titleScale 0.5s')
setTimeout(() => { input.focus() }, 300)
if (!loadFlag) {
!localSearch.isfetched && localSearch.fetchData()
input.addEventListener('input', inputEventFunction)
loadFlag = true
}
// shortcut: ESC
document.addEventListener('keydown', function f (event) {
if (event.code === 'Escape') {
closeSearch()
document.removeEventListener('keydown', f)
}
})
fixSafariHeight()
window.addEventListener('resize', fixSafariHeight)
}
const closeSearch = () => {
const bodyStyle = document.body.style
bodyStyle.width = ''
bodyStyle.overflow = ''
btf.animateOut($searchDialog, 'search_close .5s')
btf.animateOut($searchMask, 'to_hide 0.5s')
window.removeEventListener('resize', fixSafariHeight)
}
const searchClickFn = () => {
document.querySelector('#search-button > .search').addEventListener('click', openSearch)
}
const searchFnOnce = () => {
document.querySelector('#local-search .search-close-button').addEventListener('click', closeSearch)
$searchMask.addEventListener('click', closeSearch)
if (GLOBAL_CONFIG.localSearch.preload) {
localSearch.fetchData()
}
localSearch.highlightSearchWords(document.getElementById('article-container'))
}
window.addEventListener('search:loaded', () => {
const $loadDataItem = document.getElementById('loading-database')
$loadDataItem.nextElementSibling.style.display = 'block'
$loadDataItem.remove()
})
searchClickFn()
searchFnOnce()
// pjax
window.addEventListener('pjax:complete', () => {
!btf.isHidden($searchMask) && closeSearch()
localSearch.highlightSearchWords(document.getElementById('article-container'))
searchClickFn()
})
})