bfilter/trunk/bfilter.js

/*
   Fast filtering function using pre-sorted list elements
   Dobrica Pavlinusic, dpavlin@rot13.org 2004-09-06
   Matko Andjelinic, matko.andjelinic@gmail.com 2004-09-09 (contributed OO implementation)
*/

top.__bfilter_obj = new Array();


function BFilter(arr) {
        this.id_cache = Array();
        // total number of hits
        this.hits = 0;

        // store reference to this object for later (YAK)
        this.obj_count = top.__bfilter_obj.length;
        top.__bfilter_obj[this.obj_count] = this;

        // clear results html
        this.results_html = null;

        // show results after 0.2s
        this.timeout = 200;
        this.timeout_handle = null;

        if (! arr) {
                this.debug("ERROR: can't search empty array");
                return;
        }

        this.arr = arr;
        this.debug("index has "+this.arr.length+" parts");

        if (! arr.min_len) {
                alert("ERROR: index structure problem");
                return;
        } else {
                this.min_len = arr.min_len;
        }

        this.debug("index part has "+this.min_len+" parts");

        this.show_status();

        // show alert for non-existent elements?
        this.show_alert = 1;

}

BFilter.prototype.element_id = function (id,no_alert) {
        if (this.id_cache[id]) {
                return this.id_cache[id];
        } else {
                var el = self.document.getElementById(id);
                if (el) {
                        this.id_cache[id] = el;
                        return el;
                } else {
                        if (! no_alert && this.show_alert) {
                                this.show_alert = confirm("can't find element id: "+id);
                        } else {
                                // don't look it up again
                                this.id_cache[id] = null;
                        }
                }
        }
        return null;
}


BFilter.prototype.show_status = function (query,no_hits) {
        var html = "";
        if (! no_hits) {
                if (this.hits > 0) {
                        html = "shown "+this.hits+" entries";
                } else {
                        html = "no results";
                }
                if (! status) {
                        html = "Enter "+this.min_len+" letter"+(this.min_len == 1 ? '' : 's')+" to filter entries";
                        status = "";
                }
        }
        if (! query) {
                html = "Enter "+this.min_len+" letter"+(this.min_len == 1 ? '' : 's')+" to filter entries";
                query = "";
        } else {
                query = " for <em>"+query+"</em>";
        }

        var el = this.element_id("status");
        el.innerHTML = html+query+"\n";

        return true;
}

// this function is called to clean old results list
BFilter.prototype.clear_results = function () {
        var results_div = this.element_id("results");
        results_div.innerHTML = '';
        this.results_html = '';
        return true;
}

// this function is called for each result
BFilter.prototype.result = function (arr) {
        this.results_html += '<li><a href="'+arr[1]+'">'+
                (this.hits % 2 == 0 ? '<span style="background: #e0e0e0;">' : '') +
                arr[0] +
                (this.hits % 2 == 0 ? '</span>' : '') +
                '</a></li>';
        return true;
}

// this function is called when updating innerHTML with results
BFilter.prototype.show_results = function () {
        var results_div = this.element_id("results");
        if (this.results_html) {
                results_div.innerHTML = '<ul>'+this.results_html+'</ul>';
        }
        return true;
}

BFilter.prototype.debug = function (html) {

        //return;

        // check if debugging is on
        if (! html) { return 1; }

        var debug_div = this.element_id("debug",1);
        if (! debug_div) { return null; }

        debug_div.innerHTML += html + "<br>\n";

        return null;
}


// modified binary search to find first element with substring
BFilter.prototype.binarySearch = function (arr, user_filter) {
        if (!arr || typeof (user_filter) == "undefined" || !arr.length) {
                return null;
        }
        var low = 0;
        var high = arr.length - 1;
        var middlearr = parseInt(arr.length / 2);
        this.debug("binarySearch: "+low+"-("+middlearr+")-"+high+" for "+user_filter);
        var lastTry;
        while (low <= high) {
                var mid = (low + high) / 2;
                var aTry = (mid < 1) ? 0 : parseInt(mid);
        
                var curr = arr[aTry][0].substr(0,user_filter.length).toLowerCase();
                this.debug(low+"-"+high+", "+aTry+"="+curr+" last="+lastTry);
                if (curr < user_filter) {
                        low = aTry + 1;
                        continue;
                }
                if (curr > user_filter) {
                        high = aTry - 1;
                        continue;
                }
                if (curr == user_filter) {
                        high = aTry - 1;
                        lastTry = aTry;
                        continue;
                }
                return aTry;
        }
        this.debug("lastTry="+lastTry);

        if (typeof (lastTry) != "undefined") {
                return lastTry;
        } else {
                return null;
        }
}

BFilter.prototype.filter = function (user_filter) {
        this.debug("set timeout for "+this.obj_count+" to "+this.timeout);
        if (this.timeout_handle) {
                clearTimeout(this.timeout_handle);
                this.timeout_handle = null;
        }
        this.timeout_handle=setTimeout("top.__bfilter_obj["+this.obj_count+"].show_filter('"+user_filter.replace(/'/,"\\'")+"');", this.timeout);
        return true;
}

BFilter.prototype.show_filter = function (user_filter) {

        this.show_status("Showing entries with <em>"+user_filter+"</em>\n");

        if (this.timeout_handle) {
                clearTimeout(this.timeout_handle);
                this.timeout_handle = null;
                this.debug("timeout cleared");
        }

        this.clear_results();
        this.hits = 0;

        if (user_filter.length < this.min_len) {
                this.show_status();
                return;
        }

        var user_filter_lc = user_filter.toLowerCase();
        
        this.debug("filter: '"+user_filter_lc+"'");

        var part = user_filter_lc.substr(0,this.min_len);

        // no part found
        if (! this.arr[part]) {
                this.show_status(user_filter);
                this.debug("no part "+part);
                return;
        }

        // start anim icon
        //<img  src=\"pie.gif\">&nbsp;Please wait, filtering...

        var i;

        // full part? (optimization)
        if (user_filter.length == this.min_len) {
                for (i = 0; i < this.arr[part].length; i++) {
                        this.result(this.arr[part][i]);
                        this.hits++;
                }
                this.show_results();
        } else {

                var from = this.binarySearch(this.arr[part], user_filter_lc);

                if (from != null) {
                
                        this.debug("loop "+from+" ... "+this.arr[part].length);

                        for(i = from ; i < this.arr[part].length ; i++) {
                                if (this.arr[part][i][0].substring(0,user_filter.length).toLowerCase() != user_filter_lc) {
                                        this.debug("loop exit at "+i);
                                        break;
                                }
                                this.result(this.arr[part][i]);
                                this.hits++;
                        }

                        this.show_results();
                }

        }

        this.show_status(user_filter);

}

BFilter.prototype.show_all = function (user_filter) {

        this.show_status("Showing all entries\n");

        if (this.timeout_handle) {
                clearTimeout(this.timeout_handle);
                this.timeout_handle = null;
                this.debug("timeout cleared");
        }

        this.clear_results();
        this.hits = 0;

        for (part in this.arr) {
                // skip elements which are not really parts
                if (part == 'length' || part == 'min_len') continue;

                this.debug("part: "+part);
                for(var i = 0 ; i < this.arr[part].length ; i++) {
                        this.result(this.arr[part][i]);
                        this.hits++;
                }

                this.show_results();
        }

        this.show_status(user_filter);

}

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	top.__bfilter_obj = new Array();
8
9
10	function BFilter(arr) {
11	this.id_cache = Array();
12	// total number of hits
13	this.hits = 0;
14
15	// store reference to this object for later (YAK)
16	this.obj_count = top.__bfilter_obj.length;
17	top.__bfilter_obj[this.obj_count] = this;
18
19	// clear results html
20	this.results_html = null;
21
22	// show results after 0.2s
23	this.timeout = 200;
24	this.timeout_handle = null;
25
26	if (! arr) {
27	this.debug("ERROR: can't search empty array");
28	return;
29	}
30
31	this.arr = arr;
32	this.debug("index has "+this.arr.length+" parts");
33
34	if (! arr.min_len) {
35	alert("ERROR: index structure problem");
36	return;
37	} else {
38	this.min_len = arr.min_len;
39	}
40
41	this.debug("index part has "+this.min_len+" parts");
42
43	this.show_status();
44
45	// show alert for non-existent elements?
46	this.show_alert = 1;
47
48	}
49
50	BFilter.prototype.element_id = function (id,no_alert) {
51	if (this.id_cache[id]) {
52	return this.id_cache[id];
53	} else {
54	var el = self.document.getElementById(id);
55	if (el) {
56	this.id_cache[id] = el;
57	return el;
58	} else {
59	if (! no_alert && this.show_alert) {
60	this.show_alert = confirm("can't find element id: "+id);
61	} else {
62	// don't look it up again
63	this.id_cache[id] = null;
64	}
65	}
66	}
67	return null;
68	}
69
70
71	BFilter.prototype.show_status = function (query,no_hits) {
72	var html = "";
73	if (! no_hits) {
74	if (this.hits > 0) {
75	html = "shown "+this.hits+" entries";
76	} else {
77	html = "no results";
78	}
79	if (! status) {
80	html = "Enter "+this.min_len+" letter"+(this.min_len == 1 ? '' : 's')+" to filter entries";
81	status = "";
82	}
83	}
84	if (! query) {
85	html = "Enter "+this.min_len+" letter"+(this.min_len == 1 ? '' : 's')+" to filter entries";
86	query = "";
87	} else {
88	query = " for <em>"+query+"</em>";
89	}
90
91	var el = this.element_id("status");
92	el.innerHTML = html+query+"\n";
93
94	return true;
95	}
96
97	// this function is called to clean old results list
98	BFilter.prototype.clear_results = function () {
99	var results_div = this.element_id("results");
100	results_div.innerHTML = '';
101	this.results_html = '';
102	return true;
103	}
104
105	// this function is called for each result
106	BFilter.prototype.result = function (arr) {
107	this.results_html += '<li><a href="'+arr[1]+'">'+
108	(this.hits % 2 == 0 ? '<span style="background: #e0e0e0;">' : '') +
109	arr[0] +
110	(this.hits % 2 == 0 ? '</span>' : '') +
111	'</a></li>';
112	return true;
113	}
114
115	// this function is called when updating innerHTML with results
116	BFilter.prototype.show_results = function () {
117	var results_div = this.element_id("results");
118	if (this.results_html) {
119	results_div.innerHTML = '<ul>'+this.results_html+'</ul>';
120	}
121	return true;
122	}
123
124	BFilter.prototype.debug = function (html) {
125
126	//return;
127
128	// check if debugging is on
129	if (! html) { return 1; }
130
131	var debug_div = this.element_id("debug",1);
132	if (! debug_div) { return null; }
133
134	debug_div.innerHTML += html + "<br>\n";
135
136	return null;
137	}
138
139
140	// modified binary search to find first element with substring
141	BFilter.prototype.binarySearch = function (arr, user_filter) {
142	if (!arr \|\| typeof (user_filter) == "undefined" \|\| !arr.length) {
143	return null;
144	}
145	var low = 0;
146	var high = arr.length - 1;
147	var middlearr = parseInt(arr.length / 2);
148	this.debug("binarySearch: "+low+"-("+middlearr+")-"+high+" for "+user_filter);
149	var lastTry;
150	while (low <= high) {
151	var mid = (low + high) / 2;
152	var aTry = (mid < 1) ? 0 : parseInt(mid);
153
154	var curr = arr[aTry][0].substr(0,user_filter.length).toLowerCase();
155	this.debug(low+"-"+high+", "+aTry+"="+curr+" last="+lastTry);
156	if (curr < user_filter) {
157	low = aTry + 1;
158	continue;
159	}
160	if (curr > user_filter) {
161	high = aTry - 1;
162	continue;
163	}
164	if (curr == user_filter) {
165	high = aTry - 1;
166	lastTry = aTry;
167	continue;
168	}
169	return aTry;
170	}
171	this.debug("lastTry="+lastTry);
172
173	if (typeof (lastTry) != "undefined") {
174	return lastTry;
175	} else {
176	return null;
177	}
178	}
179
180	BFilter.prototype.filter = function (user_filter) {
181	this.debug("set timeout for "+this.obj_count+" to "+this.timeout);
182	if (this.timeout_handle) {
183	clearTimeout(this.timeout_handle);
184	this.timeout_handle = null;
185	}
186	this.timeout_handle=setTimeout("top.__bfilter_obj["+this.obj_count+"].show_filter('"+user_filter.replace(/'/,"\\'")+"');", this.timeout);
187	return true;
188	}
189
190	BFilter.prototype.show_filter = function (user_filter) {
191
192	this.show_status("Showing entries with <em>"+user_filter+"</em>\n");
193
194	if (this.timeout_handle) {
195	clearTimeout(this.timeout_handle);
196	this.timeout_handle = null;
197	this.debug("timeout cleared");
198	}
199
200	this.clear_results();
201	this.hits = 0;
202
203	if (user_filter.length < this.min_len) {
204	this.show_status();
205	return;
206	}
207
208	var user_filter_lc = user_filter.toLowerCase();
209
210	this.debug("filter: '"+user_filter_lc+"'");
211
212	var part = user_filter_lc.substr(0,this.min_len);
213
214	// no part found
215	if (! this.arr[part]) {
216	this.show_status(user_filter);
217	this.debug("no part "+part);
218	return;
219	}
220
221	// start anim icon
222	//<img src=\"pie.gif\"> Please wait, filtering...
223
224	var i;
225
226	// full part? (optimization)
227	if (user_filter.length == this.min_len) {
228	for (i = 0; i < this.arr[part].length; i++) {
229	this.result(this.arr[part][i]);
230	this.hits++;
231	}
232	this.show_results();
233	} else {
234
235	var from = this.binarySearch(this.arr[part], user_filter_lc);
236
237	if (from != null) {
238
239	this.debug("loop "+from+" ... "+this.arr[part].length);
240
241	for(i = from ; i < this.arr[part].length ; i++) {
242	if (this.arr[part][i][0].substring(0,user_filter.length).toLowerCase() != user_filter_lc) {
243	this.debug("loop exit at "+i);
244	break;
245	}
246	this.result(this.arr[part][i]);
247	this.hits++;
248	}
249
250	this.show_results();
251	}
252
253	}
254
255	this.show_status(user_filter);
256
257	}
258
259	BFilter.prototype.show_all = function (user_filter) {
260
261	this.show_status("Showing all entries\n");
262
263	if (this.timeout_handle) {
264	clearTimeout(this.timeout_handle);
265	this.timeout_handle = null;
266	this.debug("timeout cleared");
267	}
268
269	this.clear_results();
270	this.hits = 0;
271
272	for (part in this.arr) {
273	// skip elements which are not really parts
274	if (part == 'length' \|\| part == 'min_len') continue;
275
276	this.debug("part: "+part);
277	for(var i = 0 ; i < this.arr[part].length ; i++) {
278	this.result(this.arr[part][i]);
279	this.hits++;
280	}
281
282	this.show_results();
283	}
284
285	this.show_status(user_filter);
286
287	}
288