var suggestions = document.getElementById('suggestions');
var userinput = document.getElementById('userinput');
document.addEventListener('keydown', function(e) {
if (e.key === '/' && document.activeElement.tagName !== 'INPUT' && document.activeElement.tagName !== 'TEXTAREA') {
e.preventDefault();
userinput.focus();
}
if (e.key === 'Escape') {
userinput.blur();
suggestions.style.display = 'none';
}
});
document.addEventListener('click', function(event) {
if (!suggestions.contains(event.target) && event.target !== userinput) {
suggestions.style.display = 'none';
}
});
document.addEventListener('keydown', function(e) {
const focusable = suggestions.querySelectorAll('a');
if (suggestions.style.display === 'none' || focusable.length === 0) return;
const index = Array.from(focusable).indexOf(document.activeElement);
if (e.key === 'ArrowUp') {
e.preventDefault();
const nextIndex = index > 0 ? index - 1 : 0;
focusable[nextIndex].focus();
} else if (e.key === 'ArrowDown') {
e.preventDefault();
const nextIndex = index + 1 < focusable.length ? index + 1 : index;
focusable[nextIndex].focus();
}
});
(function() {
var index = elasticlunr.Index.load(window.searchIndex);
userinput.addEventListener('input', function() {
var value = this.value.trim();
if (!value) {
suggestions.style.display = 'none';
suggestions.innerHTML = '';
return;
}
var results = index.search(value, {
bool: "OR",
expand: true,
fields: {
title: { boost: 2 },
body: { boost: 1 }
}
});
var items = value.split(/\s+/);
suggestions.innerHTML = '';
if (results.length === 0) {
suggestions.style.display = 'none';
return;
}
suggestions.style.display = 'block';
results.slice(0, 8).forEach(function(page) {
if (page.doc.body !== '') {
var entry = document.createElement('a');
entry.href = page.ref;
entry.className = 'search-result';
entry.innerHTML = '<span class="search-title">' + escapeHtml(page.doc.title) + '</span>' +
'<span class="search-excerpt">' + makeTeaser(page.doc.body, items) + '</span>';
suggestions.appendChild(entry);
}
});
});
suggestions.addEventListener('click', function(e) {
if (e.ctrlKey || e.metaKey || e.shiftKey) {
suggestions.innerHTML = '';
suggestions.style.display = 'none';
}
});
function escapeHtml(text) {
var div = document.createElement('div');
div.textContent = text;
return div.innerHTML;
}
function makeTeaser(body, terms) {
var TERM_WEIGHT = 40;
var NORMAL_WORD_WEIGHT = 2;
var FIRST_WORD_WEIGHT = 8;
var TEASER_MAX_WORDS = 30;
var stemmedTerms = terms.map(function(w) {
return elasticlunr.stemmer(w.toLowerCase());
});
var termFound = false;
var index = 0;
var weighted = [];
var sentences = body.toLowerCase().split(". ");
for (var i in sentences) {
var words = sentences[i].split(/[\s\n]/);
var value = FIRST_WORD_WEIGHT;
for (var j in words) {
var word = words[j];
if (word.length > 0) {
for (var k in stemmedTerms) {
if (elasticlunr.stemmer(word).startsWith(stemmedTerms[k])) {
value = TERM_WEIGHT;
termFound = true;
}
}
weighted.push([word, value, index]);
value = NORMAL_WORD_WEIGHT;
}
index += word.length + 1;
}
index += 1;
}
if (weighted.length === 0) {
return body.length > TEASER_MAX_WORDS * 10
? escapeHtml(body.substring(0, TEASER_MAX_WORDS * 10)) + '...'
: escapeHtml(body);
}
var windowSize = Math.min(weighted.length, TEASER_MAX_WORDS);
var windowWeights = [];
var curSum = 0;
for (var i = 0; i < windowSize; i++) {
curSum += weighted[i][1];
}
windowWeights.push(curSum);
for (var i = 0; i < weighted.length - windowSize; i++) {
curSum -= weighted[i][1];
curSum += weighted[i + windowSize][1];
windowWeights.push(curSum);
}
var maxSumIndex = 0;
if (termFound) {
var maxFound = 0;
for (var i = windowWeights.length - 1; i >= 0; i--) {
if (windowWeights[i] > maxFound) {
maxFound = windowWeights[i];
maxSumIndex = i;
}
}
}
var teaser = [];
var startIndex = weighted[maxSumIndex][2];
for (var i = maxSumIndex; i < maxSumIndex + windowSize; i++) {
var word = weighted[i];
if (startIndex < word[2]) {
teaser.push(escapeHtml(body.substring(startIndex, word[2])));
startIndex = word[2];
}
if (word[1] === TERM_WEIGHT) {
teaser.push('<b>');
}
startIndex = word[2] + word[0].length;
teaser.push(escapeHtml(body.substring(word[2], startIndex)));
if (word[1] === TERM_WEIGHT) {
teaser.push('</b>');
}
}
teaser.push('...');
return teaser.join('');
}
})();