add methods in kb-util module; intoduce match-util module

1 files changed, 14 insertions, 132 deletions

diff --git a/pieces/suggest.js b/pieces/suggest.js
index 9c37efb..ab62cfd 100644
--- a/pieces/suggest.js
+++ b/pieces/suggest.js
@@ -1,3 +1,8 @@
+const kb = require('./kb-util.js');
+const match = require('./match-util.js');
+
+var n = 2;    // Ngram base
+
 /** (Search) SUGGESTIONS ENGINE
  * ---------------------------------------------------------------------------
  * 
@@ -79,97 +84,8 @@ function suggestions_module(options) {
     var keywordsURL = options.keywords_json;
     
     var cursor_on = { none: true };     // what product is highlighted; if not on product then { none: true }
-    
-    
-
-    /** 2.PURIFY STRING FUNCTIONS
-     * -------------------------------------------------------------------------
-     *//////////////////////////////////////////////////////////////////////////
-
-
-    /** keyboardize
-     * -------------------------------------------------------------------------
-     * translates string to keyboard-latin keys
-     * (the ones that used whan typing each letter of the word)
-     * 
-     * @param str (string): original string (utf8 of latin or greek subgroups)
-     * @return (string): latin/ascii equivalent string
-     */
-
-    // cache (keeo in global) any-character to keyboard-latin mapping
-    // --- -- -- - - -
-    var ORiGiNal = 'ςερτυθιοπασδφγηξκλζχψωβνμΕΡΤΥΘΙΟΠΑΣΔΦΓΗΞΚΛΖΧΨΩΒΝΜάέήίόύώϊΐϋΆΈΉΊΌΎΏΪΫQWERTYUIOPASDFGHJKLZXCVBNMqwertyuiopasdfghjklzxcvbnm0123456789- '.split('');
-    var kbKeyZed = 'sertyuiopasdfghjklzxcvbnmertyuiopasdfghjklzxcvbnmaehioyviiyaehioyviyqwertyuiopasdfghjklzxcvbnmqwertyuiopasdfghjklzxcvbnm0123456789- '.split('');
-    const map = new Map();
-    for (var i=0; i<ORiGiNal.length; i++) map.set(ORiGiNal[i], kbKeyZed[i]);
-
-    // "keyboardize" function
-    // --- -- -- - - -
-    function keyboardize(str) {
-        str = str.replace('\'','');
-        var out = '';
-        // [map]'s implementation is 40x faster than [for]'s
-        for (var i=0 ; i< str.length; i++)  out += map.get(str[i]);
-        return out;
-    }
-
-    /**  sanitize_GR
-     * -------------------------------------------------------------------------
-     * replaces greek accended vowels with non accended ones
-     * takes care of sigma on the end of words
-     * 
-     * @param str (string)
-     * @return sanitized string
-     */
-
-    // first cache (=create a global array)
-    // of accended to non-accended vowels mapping
-    // --- -- -- - - -
-    accented_vowels = [];   
-    [
-        'ά α', 'έ ε', 'ή η', 'ί ι', 'ϊ ι', 'ΐ ι', 'ό ο', 'ύ υ', 'ϋ υ', 'ώ ω',
-        'Ά Α', 'Έ Ε', 'Ή Η', 'Ί Ι', 'Ϊ Ι', 'Ό Ο', 'Ύ Υ', 'Ϋ Υ', 'Ώ Ω'
-    ].forEach( pair => {
-        ap = pair.split(' ');
-        accented_vowels.push({
-            a: ap[0],   // accented
-            p: ap[1]    // pure = non accended
-        });
-    })
-
-    // the actual `sanitize_GR` function code
-    // --- -- -- - - -
-    function sanitize_GR(str) {
-
-        str = str.toLowerCase();
-
-        // replace accended vowels with pure ones
-        accented_vowels.forEach( v => {
-            str = str.replaceAll(v.a, v.p);
-        });
-
-        // replace sigma on the end of words
-        str = str + ' ';
-        str = str.replaceAll('σ-', 'ς-');
-        str = str.replaceAll('σ ', 'ς ');
-        
-        return str;
-    }
-
-
-    /** clean text
-     * --- -- -- - - -
-     * removes non keyword characters [+ . , !] and internal multiple-spaces
-     * @param txt (string): product description
-     */
-    function clean_text(txt) {
-        return txt.replace('+',' ').replace('.',' ').replace(',',' ')   // change to space
-            .replace('!','').replace('\"', '')                  // remove character
-            .replace('   ',' ').replace('  ',' ');          // remove multiple spaces
-    }
-
-
 
+    
     /** replaces (correcting descriptions)
      * == construct unequivocally liked words //////////////////////////////////
      * -------------------------------------------------------------------------
@@ -262,7 +178,7 @@ function suggestions_module(options) {
      * mark linked words shall be handled as one-(key)word
      * also, edit common mistakes with suggested replaces
      * 
-     * @param str 
+     * @param str
      * @return 
      */
     function mark_explicit_links(str) {
@@ -306,41 +222,6 @@ function suggestions_module(options) {
     }
 
 
-    /** Ngram fuzzy match algorithm
-     * (simple and fast)
-     */
-    const createNgram = (word, n) => {          // Ngram creation
-        if (word.length <3)     return word;
-        const vector = [];
-        for (let i = 0; i < word.length-n+1; ++i) {
-            vector.push(word.slice(i, i + n));
-        }
-        return vector;
-    };
-    const checkSimilarity = (a, b) => {         // Ngram match score
-        if (!_allowFuzzy)    return 0;
-    
-        if (a.length > 0 && b.length > 0) {
-            const aNgram = createNgram(a, _Ngram_base);
-            const bNgram = createNgram(b, _Ngram_base);
-            let hits = 0;
-            for (let x = 0; x < aNgram.length; ++x) {
-                for (let y = 0; y < bNgram.length; ++y) {
-                    if (aNgram[x] === bNgram[y]) {
-                        hits += 1;
-                    }
-                }
-            }
-            if (hits > 0) {
-                const union = aNgram.length + bNgram.length;
-                return (2.0 * hits) / union;
-            }
-        }
-        return 0;
-    };
-
-
-
 
 
     // Search Endine's match functions
@@ -364,7 +245,8 @@ function suggestions_module(options) {
         chkArr.forEach( chk => {
             if (!found) {
                 chk_kb = keyboardize(chk);
-                if ( (chk_kb.indexOf( query ) !== -1) || (fuzzy && (checkSimilarity(chk_kb, query) > _fuzzyLimit)) ) {
+                if ( (chk_kb.indexOf( query ) !== -1)
+                || (fuzzy && (match.similarity(chk_kb, query, n) > _fuzzyLimit)) ) {
                     found = true;
                     result = chk;
                 }
@@ -518,7 +400,7 @@ function suggestions_module(options) {
 
         if (qAr.length == 1) {      // suggest 1st word //////////////////////
 
-            var kbq = keyboardize(q);
+            var kbq = kb.keyboardize(q);
 
             // loop through root-words
             // ... to match all possible suggestions;
@@ -547,14 +429,14 @@ function suggestions_module(options) {
         if (qAr.length == 2) {   // suggest 2nd word /////////////////////////
             root = qAr[0];
             last = qAr[1];
-            kbroot = keyboardize(root);
-            kblast = keyboardize(last);
+            kbroot = kb.keyboardize(root);
+            kblast = kb.keyboardize(last);
 
             // TODO:
             // change [_kwlinks.forEach] to for loop
             // ---
-            _kwlinks.forEach( it => {                   // locate the ...
-                if (is_exact_match(kbroot, it.w)) {     // exact match of root-word
+            _kwlinks.forEach( it => {           // locate the ...
+                if (match.exact(kbroot, kb.keyb_array(it.w))) {     // exact match of root-word
 
                     it.c.forEach ( wo => {              // loop the word-links ...
                         chk = check_match(kblast, wo.w, true);