| 1 |
/* |
| 2 |
Fast filtering function using pre-sorted list elements |
| 3 |
Dobrica Pavlinusic, dpavlin@rot13.org 2004-09-06 |
| 4 |
Matko Andjelinic, matko.andjelinic@gmail.com 2004-09-09 (contributed OO implementation) |
| 5 |
*/ |
| 6 |
|
| 7 |
|
| 8 |
function BFilter(arr) { |
| 9 |
this.id_cache = Array(); |
| 10 |
// total number of hits |
| 11 |
this.hits = 0; |
| 12 |
// before all results |
| 13 |
this.html_full_pre = '<ul>'; |
| 14 |
// before result |
| 15 |
this.html_pre = '<li><a href="'; |
| 16 |
// id from result |
| 17 |
this.html_mid = '">'; |
| 18 |
// title from result (which was searched also) |
| 19 |
this.html_post = '</a></li>'; |
| 20 |
// after all results |
| 21 |
this.html_full_post = '</ul>'; |
| 22 |
// highlight for every second row in results |
| 23 |
//this.html_hl_start = '<span style="background: #e0e0e0;">'; |
| 24 |
//this.html_hl_end = '</span>'; |
| 25 |
this.html_hl_start = ''; |
| 26 |
this.html_hl_end = ''; |
| 27 |
|
| 28 |
if (! arr) { |
| 29 |
this.debug("ERROR: can't search empty array"); |
| 30 |
return; |
| 31 |
} |
| 32 |
|
| 33 |
this.arr = arr; |
| 34 |
this.debug("index has "+this.arr.length+" parts"); |
| 35 |
|
| 36 |
if (! arr.min_len) { |
| 37 |
this.results("ERROR: index structure problem"); |
| 38 |
return; |
| 39 |
} else { |
| 40 |
this.min_len = arr.min_len; |
| 41 |
} |
| 42 |
|
| 43 |
this.debug("index part has "+this.min_len+" parts"); |
| 44 |
|
| 45 |
this.show_status(); |
| 46 |
|
| 47 |
} |
| 48 |
|
| 49 |
BFilter.prototype.element_id = function (id,no_alert) { |
| 50 |
if (this.id_cache[id]) { |
| 51 |
return this.id_cache[id]; |
| 52 |
} else { |
| 53 |
var el = document.getElementById(id); |
| 54 |
if (el) { |
| 55 |
this.id_cache[id] = el; |
| 56 |
return el; |
| 57 |
} else { |
| 58 |
if (! no_alert) { |
| 59 |
alert("can't find element id: "+id); |
| 60 |
} else { |
| 61 |
// don't look it up again |
| 62 |
this.id_cache[id] = null; |
| 63 |
} |
| 64 |
} |
| 65 |
} |
| 66 |
return null; |
| 67 |
} |
| 68 |
|
| 69 |
|
| 70 |
BFilter.prototype.show_status = function (status) { |
| 71 |
var html; |
| 72 |
if (this.hits > 0) { |
| 73 |
html = "shown "+this.hits+" entries"; |
| 74 |
} else { |
| 75 |
html = "no results"; |
| 76 |
} |
| 77 |
if (! status) { |
| 78 |
html = "Enter "+this.min_len+" letter"+(this.min_len == 1 ? '' : 's')+" to filter entries"; |
| 79 |
status = ""; |
| 80 |
} |
| 81 |
|
| 82 |
var el = this.element_id("status"); |
| 83 |
el.innerHTML = html+status+"\n"; |
| 84 |
} |
| 85 |
|
| 86 |
BFilter.prototype.results = function (html,clean) { |
| 87 |
|
| 88 |
if (! html) { html = ""; } |
| 89 |
|
| 90 |
// results_div.style.cursor = 'wait'; // 'auto' |
| 91 |
var results_div = this.element_id("results"); |
| 92 |
if (clean) { |
| 93 |
results_div.innerHTML = html + "\n"; |
| 94 |
} else { |
| 95 |
results_div.innerHTML += this.html_full_pre + html +"\n" + this.html_full_post; |
| 96 |
} |
| 97 |
} |
| 98 |
|
| 99 |
|
| 100 |
BFilter.prototype.debug = function (html) { |
| 101 |
|
| 102 |
//return; |
| 103 |
|
| 104 |
// check if debugging is on |
| 105 |
if (! html) { return 1; } |
| 106 |
|
| 107 |
var debug_div = this.element_id("debug",1); |
| 108 |
if (! debug_div) { return null; } |
| 109 |
|
| 110 |
debug_div.innerHTML += html + "<br>\n"; |
| 111 |
|
| 112 |
return null; |
| 113 |
} |
| 114 |
|
| 115 |
|
| 116 |
// modified binary search to find first element with substring |
| 117 |
BFilter.prototype.binarySearch = function (arr, find) { |
| 118 |
if (!arr || typeof (find) == "undefined" || !arr.length) { |
| 119 |
return null; |
| 120 |
} |
| 121 |
var low = 0; |
| 122 |
var high = arr.length - 1; |
| 123 |
var middlearr = parseInt(arr.length / 2); |
| 124 |
var lastTry; |
| 125 |
while (low <= high) { |
| 126 |
var mid = (low + high) / 2; |
| 127 |
var aTry = (mid < 1) ? 0 : parseInt(mid); |
| 128 |
|
| 129 |
var curr = arr[aTry][1].substr(0,find.length).toLowerCase(); |
| 130 |
this.debug("low="+low+" high="+high+" lastTry="+lastTry+" "+aTry+": "+curr); |
| 131 |
if (curr < find) { |
| 132 |
low = aTry + 1; |
| 133 |
continue; |
| 134 |
} |
| 135 |
if (curr > find) { |
| 136 |
high = aTry - 1; |
| 137 |
continue; |
| 138 |
} |
| 139 |
if (curr == find) { |
| 140 |
high = aTry - 1; |
| 141 |
lastTry = aTry; |
| 142 |
continue; |
| 143 |
} |
| 144 |
return aTry; |
| 145 |
} |
| 146 |
this.debug("lastTry="+lastTry); |
| 147 |
|
| 148 |
if (typeof (lastTry) != "undefined") { |
| 149 |
return lastTry; |
| 150 |
} else { |
| 151 |
return null; |
| 152 |
} |
| 153 |
} |
| 154 |
|
| 155 |
BFilter.prototype.filter = function (document, find) { |
| 156 |
|
| 157 |
this.results('',1); |
| 158 |
this.hits = 0; |
| 159 |
|
| 160 |
if (find.length < this.min_len) { |
| 161 |
this.show_status(); |
| 162 |
return; |
| 163 |
} |
| 164 |
|
| 165 |
this.debug("filter: '"+find+"'"); |
| 166 |
|
| 167 |
var find_lc = find.toLowerCase(); |
| 168 |
|
| 169 |
var part = find_lc.substr(0,this.min_len); |
| 170 |
|
| 171 |
// no part found |
| 172 |
if (! this.arr[part]) { |
| 173 |
this.show_status(" for <em>"+find+"</em><br>"); |
| 174 |
this.debug("no part "+part); |
| 175 |
return; |
| 176 |
} |
| 177 |
|
| 178 |
// start anim icon |
| 179 |
//results("<img src=\"pie.gif\"> Please wait, filtering...\n",1); |
| 180 |
|
| 181 |
var i; |
| 182 |
|
| 183 |
// full part? (optimization) |
| 184 |
if (find.length == this.min_len) { |
| 185 |
var html = ''; |
| 186 |
for (i = 0; i < this.arr[part].length; i++) { |
| 187 |
html += this.html_pre + |
| 188 |
this.arr[part][i][0] + |
| 189 |
this.html_mid + |
| 190 |
(this.hits % 2 == 0 ? this.html_hl_start : ''); |
| 191 |
//if (this.debug()) { html += i+": "; } |
| 192 |
html += this.arr[part][i][1] + |
| 193 |
(this.hits % 2 == 0 ? this.html_hl_end : '') + |
| 194 |
this.html_post + "\n"; |
| 195 |
this.hits++; |
| 196 |
} |
| 197 |
this.results(html); |
| 198 |
} else { |
| 199 |
|
| 200 |
var from = this.binarySearch(this.arr[part], find_lc); |
| 201 |
|
| 202 |
if (from != null) { |
| 203 |
|
| 204 |
this.debug("loop "+from+" ... "+this.arr[part].length); |
| 205 |
|
| 206 |
html = ''; |
| 207 |
|
| 208 |
for(i = from ; i < this.arr[part].length ; i++) { |
| 209 |
if (this.arr[part][i][1].substring(0,find.length).toLowerCase() != find_lc) { |
| 210 |
this.debug("loop exit at "+i); |
| 211 |
break; |
| 212 |
} |
| 213 |
html += this.html_pre + |
| 214 |
this.arr[part][i][0] + |
| 215 |
this.html_mid + |
| 216 |
(this.hits % 2 == 0 ? this.html_hl_start : ''); |
| 217 |
//if (this.debug()) { html += i+": "; } |
| 218 |
html += this.arr[part][i][1] + |
| 219 |
(this.hits % 2 == 0 ? this.html_hl_end : '') + |
| 220 |
this.html_post + "\n"; |
| 221 |
this.hits++; |
| 222 |
} |
| 223 |
|
| 224 |
this.results(html); |
| 225 |
} |
| 226 |
|
| 227 |
} |
| 228 |
|
| 229 |
this.show_status(" for <em>"+find+"</em>"); |
| 230 |
|
| 231 |
} |
| 232 |
|
| 233 |
|
Parent Directory
| 
Revision Log