/**
* SeekQuarry/Yioop --
* Open Source Pure PHP Search Engine, Crawler, and Indexer
*
* Copyright (C) 2009 - 2023 Chris Pollett chris@pollett.org
*
* LICENSE:
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*
* END LICENSE
*
* @author Sandhya Vissapragada, Chris Pollett
* @license https://www.gnu.org/licenses/ GPL3
* @link https://www.seekquarry.com/
* @copyright 2009 - 2023s
* @filesource
*/
/*
* Update the version number manually when ever
* suggest.js undergoes changes
*/
SUGGEST_VERSION_NO = 0;
/*
* Constants for key codes will handle
*/
KeyCodes = new Object();
KeyCodes.UP_ARROW = 38;
KeyCodes.DOWN_ARROW = 40;
/*
* Maximum number of search terms to display
*/
MAX_DISPLAY = 6;
/*
* Maximum number of characters in query to do spellsheck for
*/
MIN_SPELL_CHECK_WIDTH = 40;
/*
* Height of a search term in pixels
*/
FONT_HEIGHT = 24;
/*
* Used to delimit the end of a term in a trie.
* The value below is the default define. Might be set
* what the trie object loaded says in loadTrie
*/
END_OF_TERM_MARKER = " ";
/*
* Process to follow once onsubmit event is fired
*
* @param None
* @return None
*/
corrected_query = "";
function processSubmit()
{
updateLocalStorage();
}
/*
*
*/
function resetSuggest()
{
let suggest_dropdown = elt("suggest-dropdown");
suggest_dropdown.className = "";
suggest_dropdown.style.height = "0";
suggest_dropdown.style.visibility = "hidden";
elt('query-field').value = "";
document.activeElement.blur();
return false;
}
/*
* Steps to follow every time a key is up from the user end
* Handles up/dowm arrow keys
*
* @param Event event current event
* @return String text_field Current value from the search box
*
*/
function onTypeTerm(event, text_field)
{
let key_code_pressed;
let term_array;
let input_term = text_field.value.trim();
let suggest_results = elt("suggest-results");
let suggest_dropdown = elt("suggest-dropdown");
let query = elt("query-field").value;
let scroll_pos = 0;
let tmp_pos = 0;
let local_count = 0;
locale_terms = new Object();
local_terms_present = false;
local_suggest = true;
search_list_array = new Object();
scroll_horz = false;
out_query = false;
if (typeof transliterate == 'function') {
out_query = transliterate(query);
}
if (out_query && out_query.length > 0)
{
input_term = out_query;
}
//To find the length of an associative array
Object.size = function(obj) {
let size = 0, key;
for (key in obj) {
if (obj.hasOwnProperty(key)) size++;
}
return size;
};
concat_term = "";
if (window.event) { // IE8 and earlier
key_code_pressed = event.keyCode;
} else if (event.which) { // IE9/Firefox/Chrome/Opera/Safari
key_code_pressed = event.which;
}
term_array = input_term.split(" ");
concat_array = input_term.split(" ", term_array.length - 1);
if (input_term != "") {
for (let i = 0; i < concat_array.length; i++) {
concat_term += concat_array[i] + " ";
}
concat_term = concat_term.trim();
}
input_term = term_array[term_array.length - 1].trim(" ");
// behavior if typing keys other than up or down (notice call termSuggest)
if (key_code_pressed != KeyCodes.DOWN_ARROW &&
key_code_pressed != KeyCodes.UP_ARROW) {
search_list = "";
// First search the local storage to fetch the suggestions
if (typeof localStorage != 'undefined') {
let locale_ver = locale+'_' + SUGGEST_VERSION_NO;
if (localStorage[locale_ver] == null) {
localStorage.clear();
count = 0;
} else if (localStorage[locale_ver] != null) {
split_str = localStorage[locale_ver].split("@@");
locale_terms = JSON.parse(split_str[1]);
local_dict =JSON.parse(localStorage[locale_ver].split("@@", 1));
if (local_dict != null) {
local_terms_present = true;
termSuggest(local_dict, input_term);
local_terms_present = false;
}
let sorted_local = sortLocalTerms();
if (Object.size(search_list_array) > 0) {
search_list = "";
for (let i = 0; i < sorted_local.length ; i++) {
let split_array = sorted_local[i].split('*');
if (search_list_array[split_array[1]] != null) {
search_split =
search_list_array[split_array[1]].split("_");
search_list += "<li><span id='term" +local_count+
"' class='unselected' onclick='" +
"setSelectedTerm(\"" + local_count +
"\", \"selected\", true)' " +
"title='" + search_split[0] + "' " +
"onmouseover='setSelectedTerm(\"" +
local_count + "\",\"selected\")'" +
"onmouseout='setSelectedTerm(\""+
local_count+"\",\"unselected\")'" +
"ondblclick='termDblClick(\"" + search_split[0]+
"\",this.id)' >" + search_split[1] +
"</span></li>";
local_count++;
}
}
}
local_suggest = false;
}
}
count = local_count;
// Now search the actual dictionary trie
termSuggest(dictionary, input_term);
// insert nbsp of the number of suggestions are less than MAX_DISPLAY
short_max = MAX_DISPLAY - count;
for (let i = 0; i < short_max; i++) {
search_list += "<li><span class='unselected'> </span></li>";
}
if (count < 1) {
search_list = "";
}
suggest_dropdown.scrollTop = 0;
suggest_results.innerHTML = search_list;
//sort the list
let count_tmp=0;
Array.from(suggest_results.getElementsByTagName("LI"))
.sort((a, b) => b.getAttribute("data-frequency")
-a.getAttribute("data-frequency"))
.forEach(li => {
li.firstChild.id=("term"+count_tmp);
count_tmp+=1;
suggest_results.appendChild(li);
});
cursor_pos = -1;
num_items = count;
if (num_items == 0 || search_list == "") {
suggest_dropdown.className = "";
suggest_dropdown.style.height = "0";
suggest_dropdown.style.visibility = "hidden";
suggest_results.style.visibility = "hidden";
} else {
suggest_dropdown.className = "dropdown";
suggest_results.style.visibility = "visible";
suggest_dropdown.style.visibility = "visible";
suggest_dropdown.style.height = (FONT_HEIGHT * MAX_DISPLAY) + "px";
if (scroll_horz) {
suggest_dropdown.style.overflowX = "scroll";
} else {
suggest_dropdown.style.overflowX = "hidden";
}
}
}
// behavior on up down arrows
if (suggest_results.style.visibility == "visible") {
if (key_code_pressed == KeyCodes.DOWN_ARROW) {
if (cursor_pos < 0) {
cursor_pos = 0;
setSelectedTerm(cursor_pos, "selected", true);
} else {
if (cursor_pos < num_items - 1) {
setSelectedTerm(cursor_pos, "unselected");
cursor_pos++;
}
setSelectedTerm(cursor_pos, "selected", true);
}
scroll_count = 1;
scroll_pos = (cursor_pos - MAX_DISPLAY >= 0) ?
(cursor_pos - MAX_DISPLAY + 1) : 0;
suggest_dropdown.scrollTop = scroll_pos * FONT_HEIGHT;
} else if (key_code_pressed == KeyCodes.UP_ARROW) {
if (cursor_pos < 0) {
cursor_pos = 0;
setSelectedTerm(cursor_pos, "selected", true);
} else {
if (cursor_pos > 0) {
setSelectedTerm(cursor_pos, "unselected");
cursor_pos--;
}
setSelectedTerm(cursor_pos, "selected", true);
}
scroll_pos = (cursor_pos - MAX_DISPLAY + scroll_count >= 0) ?
(cursor_pos - MAX_DISPLAY + scroll_count) : 0;
scroll_count = (MAX_DISPLAY > scroll_count) ? scroll_count + 1:
MAX_DISPLAY;
suggest_dropdown.scrollTop = scroll_pos * FONT_HEIGHT;
}
}
}
/*
* To correct the spelling of the query words
*
* @param String word Input word
* @return String corrected_word Corrected word
*/
function correctSpelling(word)
{
let prob = 0;
let correct_threshold = 25;
let trie_subtree = exist(dictionary, word);
if (trie_subtree != false) {
prob = parseInt(trie_subtree[END_OF_TERM_MARKER]);
if (prob >= correct_threshold) {
return word;
}
}
let curr_prob = 0;
let candidates = known(edits1(word));
candidates.push(word);
let corrected_word = "";
// Use the frequencies to get the best match
for (let i = 0; i < candidates.length; i++) {
trie_subtree = exist(dictionary, candidates[i]);
if (trie_subtree != false) {
curr_prob = parseInt(trie_subtree[END_OF_TERM_MARKER]);
}
if (curr_prob > correct_threshold * prob) {
correct_threshold = 1;
prob = curr_prob;
corrected_word = candidates[i];
}
}
return corrected_word;
}
/*
* Gets the candidates for the spell correction with edit
* distance 1
*
* @param String word Input word
* @return Array set Words with edit distance - 1
*/
function edits1(word)
{
let splits = new Object();
let deletes = new Array();
let transposes =new Array();
let replaces = new Array();
let inserts = new Array();
let j = 0;
splits[""] = word;
for (let i = 0; i < word.length; i++) {
splits[word.substring(0, i + 1)] = word.substring(i+1, word.length);
}
// Deletes
for (key in splits) {
if (splits[key] != "") {
deletes[j] = key + splits[key].substring(1);
j++;
}
}
// Transposes
j = 0;
for (key in splits) {
if (splits[key].length > 1) {
transposes[j] = key + splits[key].substring(1, 2) +
splits[key].substring(0,1) + splits[key].substring(2);
j++;
}
}
// Replaces
j = 0;
for (key in splits) {
if (splits[key] != "") {
for (let i = 0;i < alpha.length; i++) {
replaces[j] = key + alpha.substring(i,i+1) +
splits[key].substring(1);
j++;
}
}
}
// Inserts
j = 0;
for (key in splits) {
for (let i=0; i < alpha.length; i++) {
inserts[j] = key + alpha.substring(i, i + 1) + splits[key];
j++;
}
}
let set =
deletes.concat(transposes).concat(replaces).concat(inserts).unique();
return set;
}
Array.prototype.unique = function() {
let a = this.concat();
for (let i = 0; i<a.length; ++i) {
for (let j=i+1; j < a.length; ++j) {
if (a[i] === a[j])
a.splice(j, 1);
}
}
return a;
}
/*
* To get the set of words which are known from the dictionary
*
* @param Array words_ip array of words
* @return Array known_words array of known words
*/
function known(words_ip)
{
let known_words = new Array();
let j=0;
let ret_array;
for (let i = 0; i < words_ip.length; i++) {
ret_array = exist(dictionary, words_ip[i]);
if (ret_array[END_OF_TERM_MARKER] != null) {
known_words[j] = words_ip[i];
j++;
}
}
return known_words;
}
/*
* To update the local storage with the previous query terms and
* create a trie on those terms
*
*/
function updateLocalStorage()
{
let trie_to_store;
trie_storage = {};
let store_term = elt("query-field").value;
let freq, k = 0;
let sorted_locale_terms = new Array();
if (localStorage) {
if (locale_terms && locale_terms[store_term] == null) {
locale_terms[store_term] = 1;
} else {
freq = parseInt(locale_terms[store_term]);
freq++;
locale_terms[store_term] = freq;
}
for (let key in locale_terms) {
sorted_locale_terms[k] = key;
k++;
}
sorted_locale_terms.sort();
// Build the trie
for (let i=0; i<sorted_locale_terms.length; i++) {
let trie_word = sorted_locale_terms[i];
let letters = trie_word.split("");
let cur = trie_storage;
for (let j=0; j < letters.length; j++) {
let letter = encode(letters[j]);
let pos = cur[ letter ];
if (pos == null) {
if (j === letters.length - 1) {
cur = cur[ letter ] = {'$' : '$'};
} else {
cur = cur[ letter ] = {};
}
} else if (pos === 0) {
cur = cur[ letter ] = { '$' : '$' };
} else {
cur = cur[ letter ];
}
}
}
}
trie_to_store = JSON.stringify(trie_storage);
localStorage.setItem(locale + '_' + SUGGEST_VERSION_NO, trie_to_store +
"@@" + JSON.stringify(locale_terms));
}
/*
* Sort the local storage words based of number of times they are queried
*
* @return Array local storage words
*/
function sortLocalTerms()
{
let local_storage_array = new Array();
if (Object.size(locale_terms) > 0) {
let j = 0;
for (let key in locale_terms) {
local_storage_array[j] = locale_terms[key] + "*"+ key;
j++;
}
}
local_storage_array.sort(termFrequencyComparison);
local_storage_array.reverse();
return local_storage_array;
}
/*
* Callback used by a sort call in sortLocalTerms to compare two
* string where before the * in the string is a term and after is a frequency
*
* @param String a in format described above
* @param String b in format described above
* @return number 0 - if same frequency, negative if b has larger frequency,
* positive otherwise
*/
function termFrequencyComparison(a, b)
{
let split_array1 = a.split('*');
let split_array2 = b.split('*');
let val1 = parseInt(split_array1[0]);
let val2 = parseInt(split_array2[0]);
return (val1 - val2);
}
/*
* To select an suggest value while up/down arrow keys are being used
* and place in the search box
*
* @param int pos index in the list items of suggest terms
* @param String class_value value for CSS class attribute for that list item
*/
function setSelectedTerm(pos, class_value, title_flag)
{
let query_field_object = elt("query-field");
if (typeof title_flag != 'undefined') {
query_field_object.value = elt("term" + pos).title;
}
elt("term" + pos).className = class_value;
}
/*
* To selects a term from the suggest dropdownlist and performs as search
*
* @param String term locwhat was clicked on
*/
function termDblClick(term, termid)
{
let results_dropdown = elt("suggest-results");
let query_field_object = elt("query-field");
query_field_object.value = term;
results_dropdown.innerHTML = "";
elt("suggest-dropdown").style.display = "none";
elt("search-form").submit();
}
/*
* Fetch words from the Trie and add to seachList with <li> </li> tags
*
* @param Array trie_array contains all search terms
* @param String parent_word the prefix want to find sub-term for in trie
* @param String highlighted_word parent_word, root_word + "<b>" + rest of
* parent
*/
function getTrieTerms(trie_array, parent_word, highlighted_word)
{
let search_terms;
let highlighted_terms;
if (trie_array != null) {
for (key in trie_array) {
if (key != END_OF_TERM_MARKER ) {
getTrieTerms(trie_array[key], parent_word + key,
highlighted_word + key);
} else {
if ( (locale_terms[decode(parent_word)] == null
&& local_terms_present == false)) {
search_terms = concat_term.trim() + " " +
decode(parent_word);
search_terms = search_terms.trim();
highlighted_terms = concat_term.trim() + " " +
decode(highlighted_word) + "</b>";
search_list += "<li data-frequency="+trie_array[key]+
"><span class='unselected' onclick='setSelectedTerm(" +
"this.id.substr(4), \"selected\", true)' " +
"title='" + search_terms + "' " +
"onmouseover='setSelectedTerm(this.id.substr(4),"+
"\"selected\")'" +
"onmouseout='setSelectedTerm(this.id.substr(4),"+
"\"unselected\")'" +
"ondblclick='termDblClick(\""+search_terms
+"\",this.id)'"+
">" + highlighted_terms + "</span></li>";
count++;
//handle long suggests phrases with horizontal scrollbar
if (search_terms.length * 24 > 1200 && !scroll_horz)
scroll_horz = true;
} else if (local_terms_present == true) {
search_terms = concat_term.trim() + " "
+ decode(parent_word);
search_terms = search_terms.trim();
highlighted_terms = concat_term.trim() + " "
+ decode(highlighted_word) + "</b>";
search_list_array[decode(parent_word)] = search_terms +
"_" +highlighted_terms;
//handle long suggests phrases with horizontal scrollbar
if (search_terms.length * 24 > 1200 && !scroll_horz)
scroll_horz = true;
}
}
}
}
}
/*
* Returns the sub trie_array under term in
* trie_array. If term does not exist in the trie_array
* returns false
*
* @param String term what to look up
* @return Array trie_array sub trie_array under term
*/
function exist(trie_array, term)
{
if (trie_array == null) {
return false;
}
for (let i = 0; i < term.length; i++) {
tmp = getUnicodeCharAndNextOffset(term, i);
if (tmp == false) return false;
next_char = tmp[0];
i = tmp[1];
enc_char = encode(next_char);
trie_array = trie_array[enc_char];
if (trie_array == null) {
return false;
}
}
return trie_array;
}
/*
* Entry point to find word completions/suggestions. Finds the portion of
* trie_array beneath term. Then using this subtrie get the first six entries.
* Six is specified in get values.
*
* @param Array trie_array - a nested array represent a trie
* @param String term - what to look up suggestions for
* @sideeffect global Array search_list has list of first six entries
*/
function termSuggest(trie_array, term)
{
last_word = false;
if (local_suggest == true) {
count = 0;
search_list = "";
}
// For US english ignore the case
if (locale == 'en-US') {
term = term.toLowerCase();
}
let tmp;
if (trie_array == null) {
return false;
}
if ((term.length) > 0) {
trie_array = exist(trie_array, term);
}
else {
return false;
}
getTrieTerms(trie_array, term, term + "<b>");
}
/* wrappers to save typing */
function decode(str) {
str = str.replace(/\+/g, '%20');
return decodeURIComponent(str);
}
/* wrappers to save typing */
function encode(str)
{
str = encodeURIComponent(str);
str = str.replace(/\'/g, '%27'); // encodeURIComponent doesn't convert
return str;
}
/*
* Extract next Unicode Char beginning at offset i in str returns Array
* with this character and the next offset
*
* This is based on code found at:
* https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects
* /String/charAt
*
* @param String str what to get the next character out of
* @param int i current offset into str
* @return Array pair of Unicode character beginning at i and the next offset
*/
function getUnicodeCharAndNextOffset(str, i)
{
let code = str.charCodeAt(i);
if (isNaN(code)) {
return '';
}
if (code < 0xD800 || code > 0xDFFF) {
return [str.charAt(i), i];
}
if (0xD800 <= code && code <= 0xDBFF) {
if (str.length <= i + 1) {
return false;
}
let next = str.charCodeAt(i + 1);
if (0xDC00 > next || next > 0xDFFF) {
return false;
}
return [str.charAt(i) + str.charAt(i + 1), i + 1];
}
if (i === 0) {
return false;
}
let prev = str.charCodeAt(i-1);
if (0xD800 > prev || prev > 0xDBFF) {
return false;
}
return [str.charAt(i + 1), i + 1];
}
/*
* Load the Trie during the launch of website
* Trie's are represented using nested arrays.
*/
function loadFiles()
{
let request = makeRequest();
let trie_loc = "";
if (request) {
request.onreadystatechange = function() {
if (request.readyState == 4 && request.status == 200 &&
request.responseText != "") {
trie = JSON.parse(request.responseText);
dictionary = trie["trie_array"];
END_OF_TERM_MARKER = trie["end_marker"];
if (typeof alpha != 'undefined')
spellCheck();
}
END_OF_TERM_MARKER = (typeof END_OF_TERM_MARKER == 'undefined') ?
' ' : END_OF_TERM_MARKER;
}
locale = document.documentElement.lang;
if (locale) {
let redirects = document.getElementsByTagName(
"html")[0].getAttribute("data-redirect");
let base_url = document.getElementsByTagName(
"html")[0].getAttribute("data-base");
if (redirects && base_url) {
trie_loc = base_url + "wd/suggest/" + locale;
} else {
trie_loc = (base_url) ? base_url : "./";
trie_loc += "?c=resource&a=suggest&locale=" + locale;
}
request.open("GET", trie_loc, true);
request.send();
}
}
}
/*
* To process spell correction
*/
function spellCheck()
{
let reference_node;
let spell_link;
let csrf_token;
if (document.getElementsByClassName) {
reference_node = document.getElementsByClassName("search-results")[0];
}
if (reference_node) {
let corrected_spell = elt("spell-check");
/* corrected_spell might not be present if WORD_SUGGEST off or on
a trending or chart page
*/
if (!corrected_spell) {
return;
}
let logged_in = (elt("csrf-token") !== null);
if (logged_in) {
csrf_token = elt("csrf-token").value;
}
let its_value = elt("its-value").value;
let query = elt("query-field").value;
if (query == "") {
return;
}
let ret_array;
let ret_word;
if (typeof localStorage != 'undefined') {
let locale_ver = locale + '_' + SUGGEST_VERSION_NO;
}
if (typeof locale_ver != 'undefined' &&
localStorage[locale_ver] != null) {
split_str = localStorage[locale_ver].split("@@");
locale_terms = JSON.parse(split_str[1]);
if (locale_terms[query] > 5) {
return; // search for a lot so don't suggest
}
}
// avoid suggesting if query contains meta words
if (query.indexOf(":") !== -1) {
return;
}
let term_array = query.split(" ");
let num_terms = term_array.length;
for (let i = 0; i < num_terms; i++) {
ret_word = "";
ret_word = correctSpelling(term_array[i].toLowerCase());
if (ret_word.trim(" ") == "") {
corrected_query += term_array[i] + " ";
} else {
corrected_query += ret_word + " ";
}
}
if (query.length > MIN_SPELL_CHECK_WIDTH) {
return;
}
if (corrected_query.trim() != query.toLowerCase().trim()) {
if (logged_in) {
let token_name = csrf_name;
spell_link = "?" + token_name + "=" + csrf_token + "&q="
+ corrected_query;
} else {
spell_link = "?q=" + corrected_query;
}
setDisplay('spell-check', true);
corrected_spell.innerHTML = "<b>" + local_strings.spell
+": <a rel='nofollow' href='" + spell_link +
"'>" + corrected_query + "</a></b>";
}
}
}
tag("body")[0].onload = loadFiles;
let ip_field = elt("query-field");
if (ip_field != null) {
ip_field.onpaste = function(e) {
setTimeout(function(){
onTypeTerm(e,ip_field);
}, 0);
}
ip_field.oncut = function(e) {
setTimeout(function(){
onTypeTerm(e,ip_field);
}, 0);
}
}