1: # The LearningOnline Network
2: # Search Catalog
3: #
4: # 03/08/2001 Scott Harrison
5: # Scott Harrison: 03/12/2001, 03/13/2001, 03/14/2001, 03/15/2001, 03/19/2001
6: # Scott Harrison: 03/20/2001
7: #
8: # Functions
9: #
10: # handler(server reference) : interacts with the Apache server layer
11: # (for /adm/searchcat URLs)
12: # simpletextfield(name,value) : returns HTML formatted string for simple text
13: # field
14: # simplecheckbox(name,value) : returns HTML formatted string for simple
15: # checkbox
16: # searchphrasefield(title,name,value) : returns HTML formatted string for
17: # a search expression phrase field
18: # dateboxes(name, defaultmonth, defaultday, defaultyear) : returns HTML
19: # formatted string
20: # for a calendar date
21: # selectbox(title,name,value,%HASH=options) : returns HTML formatted string for
22: # a selection box field
23: # advancedsearch(server reference, environment reference) : perform a complex
24: # multi-field logical query
25: # filled(field) : determines whether a given field has been filled
26: # basicsearch(server reference, environment reference) : perform a simple
27: # single-field logical query
28: # output_blank_field_error(server reference) : outputs a message saying that
29: # more fields need to be filled in
30: # output_results(output mode,
31: # server reference,
32: # environment reference,
33: # reply list reference) : outputs results from search
34: # build_SQL_query(field name, logic) : builds a SQL query string from a
35: # logical expression with AND/OR keywords
36: # recursive_SQL_query_build(field name, reverse notation expression) :
37: # builds a SQL query string from a reverse notation expression
38: # logical expression with AND/OR keywords
39:
40: package Apache::lonsearchcat;
41:
42: use strict;
43: use Apache::Constants qw(:common);
44: use Apache::lonnet();
45: use Apache::File();
46: use CGI qw(:standard);
47: use Text::Query;
48:
49: my %language;
50: my $scrout;
51: my %metadatafields;
52: my %cprtag;
53: my %mimetag;
54:
55: sub handler {
56: my $r = shift;
57:
58: # -------------------------------------- see if called from an interactive mode
59: map {
60: my ($name, $value) = split(/=/,$_);
61: $value =~ tr/+/ /;
62: $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
63: if ($name eq 'catalogmode') {
64: $ENV{'form.'.$name}=$value;
65: }
66: } (split(/&/,$ENV{'QUERY_STRING'}));
67:
68: $r->content_type('text/html');
69: $r->send_http_header;
70: return OK if $r->header_only;
71:
72: %metadatafields=();
73:
74: my $hidden='';
75: $hidden=<<END if $ENV{'form.catalogmode'} eq 'interactive';
76: <input type='hidden' name='catalogmode' value='interactive'>
77: END
78:
79: # ------------------------------------------------ First, check out environment
80: $metadatafields{'owner'}=$ENV{'user.name'}.'@'.$ENV{'user.domain'};
81:
82: # --------------------------------- Compute various listings of metadata values
83:
84: %language=();
85: $language{'any'}='Any language';
86: {
87: my $fh=Apache::File->new($r->dir_config('lonTabDir').'/language.tab');
88: map {
89: $_=~/(\w+)\s+([\w\s\-]+)/;
90: $language{$1}=$2;
91: } <$fh>;
92: }
93:
94: %cprtag=();
95: $cprtag{'any'}='Any copyright/distribution';
96: {
97: my $fh=Apache::File->new($r->dir_config('lonIncludes').'/copyright.tab');
98: map {
99: $_=~/(\w+)\s+([\w\s\-]+)/;
100: $cprtag{$1}=$2;
101: } <$fh>;
102: }
103:
104: %mimetag=();
105: $mimetag{'any'}='Any type';
106: {
107: my $fh=Apache::File->new($r->dir_config('lonTabDir').'/filetypes.tab');
108: map {
109: $_=~/(\w+)\s+(\w+)\s+([\w\s\-]+)/;
110: $mimetag{$1}=".$1 $3";
111: } <$fh>;
112: }
113:
114: if ($ENV{'form.basicsubmit'} eq 'SEARCH') {
115: return &basicsearch($r,\%ENV);
116: }
117: elsif ($ENV{'form.advancedsubmit'} eq 'SEARCH') {
118: return &advancedsearch($r,\%ENV);
119: }
120:
121: $scrout=''; # building a part of screen output
122: $scrout.=&searchphrasefield('Limit by title','title',
123: $ENV{'form.title'});
124:
125: $scrout.=&searchphrasefield('Limit by author','author',
126: $ENV{'form.author'});
127:
128: $scrout.=&searchphrasefield('Limit by subject','subject',
129: $ENV{'form.subject'});
130:
131: $scrout.=&searchphrasefield('Limit by keywords','keywords',
132: $ENV{'form.keywords'});
133:
134: $scrout.=&searchphrasefield('Limit by URL','url',
135: $ENV{'form.url'});
136:
137: $scrout.=&searchphrasefield('Limit by version','version',
138: $ENV{'form.version'});
139:
140: $scrout.=&searchphrasefield('Limit by notes','notes',
141: $ENV{'form.notes'});
142:
143: $scrout.=&searchphrasefield('Limit by abstract','abstract',
144: $ENV{'form.abstract'});
145:
146: $ENV{'form.mime'}='notxxx' unless length($ENV{'form.mime'});
147: $scrout.=&selectbox('Limit by MIME type','mime',
148: $ENV{'form.mime'},%mimetag);
149:
150: $ENV{'form.language'}='any' unless length($ENV{'form.language'});
151:
152: $scrout.=&selectbox('Limit by language','language',
153: $ENV{'form.language'},%language);
154:
155:
156: # ------------------------------------------------ Compute date selection boxes
157: $scrout.=<<CREATIONDATESTART;
158: <p>
159: <font color="#800000" face="helvetica"><b>LIMIT BY CREATION DATE RANGE:</b>
160: </font>
161: <br>
162: between:
163: CREATIONDATESTART
164: $scrout.=&dateboxes('creationdatestart',1,1,1976,
165: $ENV{'form.creationdatestart_month'},
166: $ENV{'form.creationdatestart_day'},
167: $ENV{'form.creationdatestart_year'},
168: );
169: $scrout.=<<CREATIONDATEEND;
170: and:
171: CREATIONDATEEND
172: $scrout.=&dateboxes('creationdateend',12,31,2051,
173: $ENV{'form.creationdateend_month'},
174: $ENV{'form.creationdateend_day'},
175: $ENV{'form.creationdateend_year'},
176: );
177: $scrout.="</p>";
178:
179: $scrout.=<<LASTREVISIONDATESTART;
180: <p>
181: <font color="#800000" face="helvetica"><b>LIMIT BY LAST REVISION DATE RANGE:
182: </b></font>
183: <br>between:
184: LASTREVISIONDATESTART
185: $scrout.=&dateboxes('lastrevisiondatestart',1,1,1976,
186: $ENV{'form.lastrevisiondatestart_month'},
187: $ENV{'form.lastrevisiondatestart_day'},
188: $ENV{'form.lastrevisiondatestart_year'},
189: );
190: $scrout.=<<LASTREVISIONDATEEND;
191: and:
192: LASTREVISIONDATEEND
193: $scrout.=&dateboxes('lastrevisiondateend',12,31,2051,
194: $ENV{'form.lastrevisiondateend_month'},
195: $ENV{'form.lastrevisiondateend_day'},
196: $ENV{'form.lastrevisiondateend_year'},
197: );
198: $scrout.='</p>';
199:
200: $scrout.=&searchphrasefield('Limit by publisher/owner','owner',
201: $ENV{'form.owner'});
202: # $metadatafields{'owner'});
203:
204: $ENV{'form.copyright'}='any' unless length($ENV{'form.copyright'});
205: $scrout.=&selectbox('Limit by copyright/distribution','copyright',
206: $ENV{'form.copyright'},%cprtag);
207:
208: # ------------------------------------------- Compute customized metadata field
209: $scrout.=<<CUSTOMMETADATA;
210: <p>
211: <font color="#800000" face="helvetica"><b>LIMIT BY OTHER METADATA FIELDS:</b>
212: </font>
213: For author-specific metadata, enter in an expression in the form of
214: <i>key</i>=<i>value</i> separated by operators such as AND or OR.<br>
215: <b>Example:</b> grandmother=75 OR grandfather=85
216: <br>
217: CUSTOMMETADATA
218: $scrout.=&simpletextfield('custommetadata',$ENV{'form.custommetadata'});
219: $scrout.=' <i>initial users of this system do not need to worry about this option</i>';
220:
221: # ---------------------------------------------------------------- Print screen
222: $r->print(<<ENDDOCUMENT);
223: <html>
224: <head>
225: <title>The LearningOnline Network with CAPA</title>
226: </head>
227: <body bgcolor="#FFFFFF">
228: <img align=right src=/adm/lonIcons/lonlogos.gif>
229: <h1>Search Catalog</h1>
230: <form method="post" action="/adm/searchcat">
231: $hidden
232: <hr>
233: <h3>Basic Search</h3>
234: <p>
235: Enter terms or phrases separated by search operators
236: such as AND or OR then press SEARCH below. Terms should be specific
237: to the title, author, subject, notes, or abstract information associated
238: with a resource.
239: <br>
240: ENDDOCUMENT
241: $r->print(&simpletextfield('basicexp',$ENV{'form.basicexp'}));
242: $r->print(' ');
243: $r->print(&simplecheckbox('titleonly',$ENV{'form.titleonly'}));
244: $r->print('<font color="#800000">Title only</font> ');
245: $r->print(&simplecheckbox('allversions',$ENV{'form.allversions'}));
246: $r->print(<<ENDDOCUMENT);
247: <font color="#800000">Search historic archives</font>
248: <br>
249: <input type="submit" name="basicsubmit" value="SEARCH">
250: <input type="reset" name="reset" value="RESET">
251: <input type="button" name="close" value="CLOSE" onClick="self.close()">
252: </p>
253: <hr>
254: <h3>Advanced Search</h3>
255: $scrout
256: <p>
257: <input type="submit" name="advancedsubmit" value="SEARCH">
258: <input type="reset" name="reset" value="RESET">
259: <input type="button" name="close" value="CLOSE" onClick="self.close()">
260: </p>
261: </form>
262: </body>
263: </html>
264: ENDDOCUMENT
265: return OK;
266: }
267:
268: # --------------------------------------------------------- Various form fields
269:
270: sub simpletextfield {
271: my ($name,$value)=@_;
272: return '<input type=text name="'.$name.'" size=20 value="'.$value.'">';
273: }
274:
275: sub simplecheckbox {
276: my ($name,$value)=@_;
277: my $checked='';
278: $checked="CHECKED" if $value eq 'on';
279: return '<input type=checkbox name="'.$name.'" '. $checked . '>';
280: }
281:
282: sub searchphrasefield {
283: my ($title,$name,$value)=@_;
284: my $instruction=<<END;
285: Enter terms or phrases separated by search operators such
286: as AND or OR.
287: END
288: my $uctitle=uc($title);
289: return "\n<p><font color=\"#800000\" face=\"helvetica\"><b>$uctitle:</b>".
290: "</FONT> $instruction<br>".
291: '<input type=text name="'.$name.'" size=80 value="'.$value.'">';
292: }
293:
294: sub dateboxes {
295: my ($name,$defaultmonth,$defaultday,$defaultyear,
296: $currentmonth,$currentday,$currentyear)=@_;
297: ($defaultmonth,$defaultday,$defaultyear)=('','','');
298: my $month=<<END;
299: <select name="${name}_month">
300: <option value='$defaultmonth'> </option>
301: <option value="1">January</option>
302: <option value="2">February</option>
303: <option value="3">March</option>
304: <option value="4">April</option>
305: <option value="5">May</option>
306: <option value="6">June</option>
307: <option value="7">July</option>
308: <option value="8">August</option>
309: <option value="9">September</option>
310: <option value="10">October</option>
311: <option value="11">November</option>
312: <option value="12">December</option>
313: </select>
314: END
315: $month=~s/(\"$currentmonth\")/$1 SELECTED/ if length($currentmonth);
316: my $day=<<END;
317: <select name="${name}_day">
318: <option value='$defaultday'> </option>
319: <option value="1">1</option>
320: <option value="2">2</option>
321: <option value="3">3</option>
322: <option value="4">4</option>
323: <option value="5">5</option>
324: <option value="6">6</option>
325: <option value="7">7</option>
326: <option value="8">8</option>
327: <option value="9">9</option>
328: <option value="10">10</option>
329: <option value="11">11</option>
330: <option value="12">12</option>
331: <option value="13">13</option>
332: <option value="14">14</option>
333: <option value="15">15</option>
334: <option value="16">16</option>
335: <option value="17">17</option>
336: <option value="18">18</option>
337: <option value="19">19</option>
338: <option value="20">20</option>
339: <option value="21">21</option>
340: <option value="22">22</option>
341: <option value="23">23</option>
342: <option value="24">24</option>
343: <option value="25">25</option>
344: <option value="26">26</option>
345: <option value="27">27</option>
346: <option value="28">28</option>
347: <option value="29">29</option>
348: <option value="30">30</option>
349: <option value="31">31</option>
350: </select>
351: END
352: $day=~s/(\"$currentday\")/$1 SELECTED/ if length($currentday);
353: my $year=<<END;
354: <select name="${name}_year">
355: <option value='$defaultyear'> </option>
356: <option value="1976">1976</option>
357: <option value="1977">1977</option>
358: <option value="1978">1978</option>
359: <option value="1979">1979</option>
360: <option value="1980">1980</option>
361: <option value="1981">1981</option>
362: <option value="1982">1982</option>
363: <option value="1983">1983</option>
364: <option value="1984">1984</option>
365: <option value="1985">1985</option>
366: <option value="1986">1986</option>
367: <option value="1987">1987</option>
368: <option value="1988">1988</option>
369: <option value="1989">1989</option>
370: <option value="1990">1990</option>
371: <option value="1991">1991</option>
372: <option value="1992">1992</option>
373: <option value="1993">1993</option>
374: <option value="1994">1994</option>
375: <option value="1995">1995</option>
376: <option value="1996">1996</option>
377: <option value="1997">1997</option>
378: <option value="1998">1998</option>
379: <option value="1999">1999</option>
380: <option value="2000">2000</option>
381: <option value="2001">2001</option>
382: <option value="2002">2002</option>
383: <option value="2003">2003</option>
384: <option value="2004">2004</option>
385: <option value="2005">2005</option>
386: <option value="2006">2006</option>
387: <option value="2007">2007</option>
388: <option value="2008">2008</option>
389: <option value="2009">2009</option>
390: <option value="2010">2010</option>
391: <option value="2011">2011</option>
392: <option value="2012">2012</option>
393: <option value="2013">2013</option>
394: <option value="2014">2014</option>
395: <option value="2015">2015</option>
396: <option value="2016">2016</option>
397: <option value="2017">2017</option>
398: <option value="2018">2018</option>
399: <option value="2019">2019</option>
400: <option value="2020">2020</option>
401: <option value="2021">2021</option>
402: <option value="2022">2022</option>
403: <option value="2023">2023</option>
404: <option value="2024">2024</option>
405: <option value="2025">2025</option>
406: <option value="2026">2026</option>
407: <option value="2027">2027</option>
408: <option value="2028">2028</option>
409: <option value="2029">2029</option>
410: <option value="2030">2030</option>
411: <option value="2031">2031</option>
412: <option value="2032">2032</option>
413: <option value="2033">2033</option>
414: <option value="2034">2034</option>
415: <option value="2035">2035</option>
416: <option value="2036">2036</option>
417: <option value="2037">2037</option>
418: <option value="2038">2038</option>
419: <option value="2039">2039</option>
420: <option value="2040">2040</option>
421: <option value="2041">2041</option>
422: <option value="2042">2042</option>
423: <option value="2043">2043</option>
424: <option value="2044">2044</option>
425: <option value="2045">2045</option>
426: <option value="2046">2046</option>
427: <option value="2047">2047</option>
428: <option value="2048">2048</option>
429: <option value="2049">2049</option>
430: <option value="2050">2050</option>
431: <option value="2051">2051</option>
432: </select>
433: END
434: $year=~s/(\"$currentyear\")/$1 SELECTED/ if length($currentyear);
435: return "$month$day$year";
436: }
437:
438: sub selectbox {
439: my ($title,$name,$value,%options)=@_;
440: my $uctitle=uc($title);
441: my $selout="\n<p><font color=\"#800000\" face=\"helvetica\"><b>$uctitle:".
442: "</b></font><br>".'<select name="'.$name.'">';
443: map {
444: $selout.='<option value="'.$_.'"';
445: if ($_ eq $value) { $selout.=' selected'; }
446: $selout.='>'.$options{$_}.'</option>';
447: } sort keys %options;
448: return $selout.'</select>';
449: }
450:
451: # ------------------------------------------------ Performing a advanced search
452: sub advancedsearch {
453: my ($r,$envhash)=@_;
454: my %ENV=%{$envhash};
455:
456: my $fillflag=0;
457: for my $field ('title','author','subject','keywords','url','version',
458: 'notes','abstract','mime','language','owner',
459: 'custommetadata') {
460: if (&filled($ENV{"form.$field"})) {
461: $fillflag++;
462: }
463: }
464:
465: unless ($fillflag) {
466: &output_blank_field_error($r);
467: return OK;
468: }
469:
470: my $query='';
471: # my $concatarg=join('," ",',
472: # ('title', 'author', 'subject', 'notes', 'abstract'));
473:
474: $query="select * from metadata where concat(title) like '\%$ENV{'form.title'}\%'";
475: my $reply=&Apache::lonnet::metadata_query($query);
476:
477: &output_results('Advanced',$r,$envhash,$reply);
478: return OK;
479: }
480:
481: # ---------------------------------------------------- see if a field is filled
482: sub filled {
483: my ($field)=@_;
484: if ($field=~/\S/) {
485: return 1;
486: }
487: else {
488: return 0;
489: }
490: }
491:
492: # --------------------------------------------------- Performing a basic search
493: sub basicsearch {
494: my ($r,$envhash)=@_;
495: my %ENV=%{$envhash};
496:
497: unless (&filled($ENV{'form.basicexp'})) {
498: &output_blank_field_error($r);
499: return OK;
500: }
501:
502: my $query='';
503: my $concatarg=join('," ",',
504: ('title', 'author', 'subject', 'notes', 'abstract'));
505:
506: $query="select * from metadata where concat($concatarg) like '\%$ENV{'form.basicexp'}\%'";
507: my $reply=&Apache::lonnet::metadata_query($query);
508: &output_results('Basic',$r,$envhash,$reply);
509: return OK;
510: }
511:
512: sub output_blank_field_error {
513: my ($r)=@_;
514: # make query information persistent to allow for subsequent revision
515: my $persistent='';
516: map {
517: if (/^form\./ && !/submit/) {
518: my $name=$_;
519: my $key=$name;
520: $name=~s/^form\.//;
521: $persistent.=<<END;
522: <INPUT TYPE='hidden' NAME='$name' VALUE='$ENV{$key}'>
523: END
524: }
525: } (keys %ENV);
526:
527: $r->print(<<BEGINNING);
528: <html>
529: <head>
530: <title>The LearningOnline Network with CAPA</title>
531: BEGINNING
532: $r->print(<<RESULTS);
533: </head>
534: <body bgcolor="#ffffff">
535: <img align=right src=/adm/lonIcons/lonlogos.gif>
536: <h1>Search Catalog</h1>
537: <form method="post" action="/adm/searchcat">
538: $persistent
539: <input type='button' value='Revise search request'
540: onClick='this.form.submit();'>
541: <input type='button' value='CLOSE'
542: onClick='self.close();'>
543: <hr>
544: <h3>Helpful Message</h3>
545: <p>
546: Incorrect search query due to blank entry fields.
547: You need to fill in the relevant
548: fields on the search page in order for a query to be
549: processed.
550: </p>
551: </body>
552: </html>
553: RESULTS
554: }
555:
556: # ----------------------------- format and output results based on a reply list
557: sub output_results {
558: my ($mode,$r,$envhash,@replylist)=@_;
559: my %ENV=%{$envhash};
560: foreach my $reply (@replylist) {
561:
562: my @results;
563:
564: my $replyfile='';
565: $reply=~/^([\.\w]+)$/; # must do since 'use strict' checks for tainting
566: $replyfile=$r->dir_config('lonDaemons').'/tmp/'.$1;
567: $reply=~/(.*?)\_/;
568: my $hostname=$1;
569:
570: {
571: while (1) {
572: last if -e $replyfile;
573: sleep 1;
574: }
575: # QUESTION: how should I handle this error condition..
576: # I'm sure there is syntax elsewhere I can use..
577: my $fh=Apache::File->new($replyfile) or
578: ($r->print('file cannot be opened') and return OK);
579: @results=<$fh>;
580: }
581:
582: my $compiledresult='';
583:
584: foreach my $result (@results) {
585: my ($title,$author,$subject,$url,$keywords,$version,
586: $notes,$abstract,$mime,$lang,
587: $creationdate,$lastrevisiondate,$owner,$copyright
588: )=map {&Apache::lonnet::unescape($_)} (split(/\,/,$result));
589: my $shortabstract=$abstract;
590: $shortabstract=substr($abstract,0,200) if length($abstract)>200;
591: $compiledresult.=<<END;
592: <p>
593: END
594: $compiledresult.=<<END if $ENV{'form.catalogmode'} eq 'interactive';
595: <font size='-1'><INPUT TYPE="button" NAME="returnvalues" VALUE="SELECT"
596: onClick="javascript:select_data('$title','$url')">
597: </font>
598: <br>
599: END
600: $compiledresult.=<<END;
601: <b>URL: </b> <A HREF="http://$ENV{'HTTP_HOST'}$url" TARGET='search_preview'>$url</A>
602: <br>
603: <b>Title:</b> $title<br>
604: <b>Author(s):</b> $author<br>
605: <b>Subject:</b> $subject<br>
606: <b>Keyword(s):</b> $keywords<br>
607: <b>Notes:</b> $notes<br>
608: <b>Abstract:</b> $shortabstract<br>
609: <b>MIME Type:</b> $mimetag{$mime}<br>
610: <b>Language:</b> $language{$lang}<br>
611: <b>Creation Date:</b> $creationdate<br>
612: <b>Last Revision Date:</b> $lastrevisiondate<br>
613: <b>Publisher/Owner:</b> $owner<br>
614: <b>Copyright/Distribution:</b> $copyright<br>
615: <b>Repository Location:</b> $hostname
616: </p>
617: END
618: }
619:
620: unless ($compiledresult) {
621: $compiledresult="There were no results that matched your query";
622: }
623:
624: # make query information persistent to allow for subsequent revision
625: my $persistent='';
626: map {
627: if (/^form\./ && !/submit/) {
628: my $name=$_;
629: my $key=$name;
630: $name=~s/^form\.//;
631: $persistent.=<<END;
632: <INPUT TYPE='hidden' NAME='$name' VALUE='$ENV{$key}'>
633: END
634: }
635: } (keys %ENV);
636:
637: $r->print(<<BEGINNING);
638: <html>
639: <head>
640: <title>The LearningOnline Network with CAPA</title>
641: BEGINNING
642: $r->print(<<SCRIPT) if $ENV{'form.catalogmode'} eq 'interactive';
643: <script>
644: function select_data(title,url) {
645: changeTitle(title);
646: changeURL(url);
647: }
648: function changeTitle(val) {
649: if (opener.inf.document.forms.resinfo.elements.t) {
650: opener.inf.document.forms.resinfo.elements.t.value=val;
651: }
652: }
653: function changeURL(val) {
654: if (opener.inf.document.forms.resinfo.elements.u) {
655: opener.inf.document.forms.resinfo.elements.u.value=val;
656: }
657: }
658: </script>
659: SCRIPT
660: $r->print(<<RESULTS);
661: </head>
662: <body bgcolor="#ffffff">
663: <img align=right src=/adm/lonIcons/lonlogos.gif>
664: <h1>Search Catalog</h1>
665: <form method="post" action="/adm/searchcat">
666: <input type='button' value='Revise search request'
667: onClick='this.form.submit();'>
668: <input type='button' value='CLOSE'
669: onClick='self.close();'>
670: $persistent
671: <hr>
672: <h3>Search Query</h3>
673: RESULTS
674: if ($mode eq 'Basic') {
675: $r->print(<<RESULTS);
676: <p>
677: <b>Basic search:</b> $ENV{'form.basicexp'}
678: </p>
679: RESULTS
680: elsif ($mode eq 'Advanced') {
681: $r->print(<<RESULTS);
682: <p>
683: <b>Advanced search</b>
684: </p>
685: RESULTS
686: }
687: <h3>Search Results</h3>
688: $compiledresult
689: </body>
690: </html>
691: RESULTS
692: }
693: }
694:
695: # ------------------------------------------------------------- build_SQL_query
696: sub build_SQL_query {
697: my ($field_name,$logic_statement)=@_;
698: my $q=new Text::Query('abc',
699: -parse => 'Text::Query::ParseAdvanced',
700: -build => 'Text::Query::Build');
701: $q->prepare($statement);
702: my $matchexp=${$q}{'matchexp'}; chomp $matchexp;
703: my $sql_query=&recursive_SQL_query_build($field_name,$matchexp);
704: }
705:
706: # - Recursively parse a reverse notation expression into a SQL query expression
707: sub recursive_SQL_query_build {
708: my ($dkey,$pattern)=@_;
709: my @matches=($pattern=~/(\[[^\]|\[]*\])/g);
710: return $pattern unless @matches;
711: foreach my $match (@matches) {
712: $match=~/\[ (\w+)\s(.*) \]/;
713: ($key,$value)=($1,$2);
714: my $replacement='';
715: if ($key eq 'literal') {
716: $replacement="($dkey like \"\%$value\%\")";
717: }
718: elsif ($key eq 'and') {
719: $value=~/(.*[\"|\)]) ([|\(|\^].*)/;
720: $replacement="($1 AND $2)";
721: }
722: elsif ($key eq 'or') {
723: $value=~/(.*[\"|\)]) ([|\(|\^].*)/;
724: $replacement="($1 OR $2)";
725: }
726: substr($pattern,
727: index($pattern,$match),
728: length($match),
729: $replacement
730: );
731: }
732: &recursive_SQL_query_build($dkey,$pattern);
733: }
734:
735: 1;
736: __END__
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