# The LearningOnline Network with CAPA
#
# Search Catalog
#
# YEAR=2001
# 03/08/2001 Scott Harrison
# Scott Harrison: 03/12/2001, 03/13/2001, 03/14/2001, 03/15/2001, 03/19/2001
# Scott Harrison: 03/20/2001, 03/21/2001, 03/22/2001, 03/26/2001, 03/27/2001
# Scott Harrison: 04/02/2001, 08/15/2001, 08/24/2001, 08/25/2001
# 10/12,10/14,10/15,10/16 Scott Harrison
###############################################################################
##                                                                           ##
## ORGANIZATION OF THIS PERL MODULE                                          ##
##                                                                           ##
## 1. Description of functions                                               ##
## 2. Modules used by this module                                            ##
## 3. Choices for different output views (detailed, summary, xml, etc)       ##
## 4. BEGIN block (to be run once after compilation)                         ##
## 5. Handling routine called via Apache and mod_perl                        ##
## 6. Other subroutines                                                      ##
##                                                                           ##
###############################################################################

# ---------------------------------------------------- Description of functions
#
#
# === WEB HANDLER FUNCTIONS
# BEGIN() : run once after compilation to initialize values
# handler(server reference) : interacts with the Apache server layer
#                             (for /adm/searchcat URLs)
# get_unprocessed_cgi() : reads in critical name/value pairs that may have not
#                         been processed and passed into %ENV by the web server
# make_persistent() : makes a set of hidden HTML fields to make
#                     SQL search interface information to be persistent
#
#
# === WEB INTERFACE COMPONENT FUNCTIONS
# simpletextfield(name,value) : returns HTML formatted string for simple text
#                               field
# simplecheckbox(name,value) : returns HTML formatted string for simple
#                              checkbox
# searchphrasefield(title,name,value) : returns HTML formatted string for
#                                       a search expression phrase field
# dateboxes(name, defaultmonth, defaultday, defaultyear) : returns HTML
#                                                          formatted string
#                                                          for a calendar date
# selectbox(title,name,value,%HASH=options) : returns HTML formatted string for
#                                             a selection box field
#
#
# === SEARCH FUNCTIONS
# advancedsearch(server reference, environment reference) : perform a complex
#                                  multi-field logical query
# basicsearch(server reference, environment reference) : perform a simple
#                               single-field logical query
# build_SQL_query(field name, logic) : builds a SQL query string from a
#                                      logical expression with AND/OR keywords
# build_custommetadata_query(field_name, logic_statement) : builds a perl
#                 regular expression from a logical expression with AND/OR
#                 keywords
# recursive_SQL_query_build(field name, reverse notation expression) : 
#                 builds a SQL query string from a reverse notation expression
#                 logical expression with AND/OR keywords
# build_date_queries(cmonth1, cday1, cyear1, cmonth2, cday2, cyear2,
#                    lmonth1, lday1, lyear1, lmonth2, lday2, lyear2) :
#                 Builds a SQL logic query to check time/date entries.
#
#
# === OUTPUTTING RESULTS FUNCTION
# output_results(output mode,
#                server reference, 
#                environment reference,
#                reply list reference) : outputs results from search
#
#
# === DIFFERENT WAYS TO VIEW METADATA RECORDS
# detailed_citation_view(ORDERED METADATA LIST FOR A RESULT OBJECT INSTANCE) :
#          see metadata viewing notes below 
# summary_view(ORDERED METADATA LIST FOR A RESULT OBJECT INSTANCE) :
#          see metadata viewing notes below 
# fielded_format_view(ORDERED METADATA LIST FOR A RESULT OBJECT INSTANCE) :
#          see metadata viewing notes below 
# xml_sgml_view(ORDERED METADATA LIST FOR A RESULT OBJECT INSTANCE) :
#          see metadata viewing notes below 
#  ___________________________________________________________________________
# | * Metadata viewing notes                                                  |
# | Output is a HTML-ified string.                                            |
# | Input arguments are title, author, subject, url, keywords, version, notes,|
# | short abstract, mime, language, creation date, last revision date, owner, |
# | copyright, hostname, httphost, and extra custom metadata to show.         |
#  ---------------------------------------------------------------------------
#
#
# === TEST CONDITIONAL FUNCTIONS
# filled(field) : determines whether a given field has been filled
#
#
# === ERROR FUNCTIONS
# output_blank_field_error(server reference) : outputs a message saying that
#                                              more fields need to be filled in
# output_date_error(server reference, error message) : outputs
#         an error message specific to bad date format.

package Apache::lonsearchcat;

# ------------------------------------------------- modules used by this module
use strict;
use Apache::Constants qw(:common);
use Apache::lonnet();
use Apache::File();
use CGI qw(:standard);
use Text::Query;
use GDBM_File;

# ---------------------------------------- variables used throughout the module

# -- information holders
my %language; # holds contents of language.tab
my %cprtag; # holds contents of copyright.tab
my %mimetag; # holds contents of filetypes.tab
my %hostdomains; # matches host name to host domain
my %hostips; # matches host name to host ip
my %hitcount; # stores number of hits per host

# -- dynamically rendered interface components
my $closebutton; # button that closes the search window
my $importbutton; # button to take the selected results and go to group sorting

# -- miscellaneous variables
my $scrout; # string that holds portions of the screen output
my $yourself; # allows for quickly limiting to oneself
my %hash;

# ------------------------------------------ choices for different output views
# Detailed Citation View ---> sub detailed_citation_view
# Summary View ---> sub summary_view
# Fielded Format ---> sub fielded_format_view
# XML/SGML ---> sub xml_sgml_view
my $basicviewselect=<<END;
<select name='basicviewselect'>
<option value='Detailed Citation View'>Detailed Citation View</option>
<option value='Summary View'>Summary View</option>
<option value='Fielded Format'>Fielded Format</option>
<option value='XML/SGML'>XML/SGML</option>
</select>
END
my $advancedviewselect=<<END;
<select name='advancedviewselect'>
<option value='Detailed Citation View'>Detailed Citation View</option>
<option value='Summary View'>Summary View</option>
<option value='Fielded Format'>Fielded Format</option>
<option value='XML/SGML'>XML/SGML</option>
</select>
END

# ----------------------------------------------------------------------- BEGIN
sub BEGIN {
# --------------------------------- Compute various listings of metadata values
    $language{'any'}='Any language';
    {
	my $fh=Apache::File->new($Apache::lonnet::perlvar{'lonTabDir'}.
				 '/language.tab');
	map {
	    $_=~/(\w+)\s+([\w\s\-]+)/; chomp;
	    $language{$1}=$2;
	} <$fh>;
    }
    $cprtag{'any'}='Any copyright/distribution';
    {
	my $fh=Apache::File->new($Apache::lonnet::perlvar{'lonIncludes'}.
				 '/copyright.tab');
	map {
	    $_=~/(\w+)\s+([\w\s\-]+)/; chomp;
	    $cprtag{$1}=$2;
	} <$fh>;
    }
    $mimetag{'any'}='Any type';
    {
	my $fh=Apache::File->new($Apache::lonnet::perlvar{'lonTabDir'}.
				 '/filetypes.tab');
	map {
	    $_=~/(\w+)\s+(\w+)\s+([\w\s\-]+)/; chomp;
	    $mimetag{$1}=".$1 $3";
	} <$fh>;
    }
    {
	my $fh=Apache::File->new($Apache::lonnet::perlvar{'lonTabDir'}.
				 '/hosts.tab');
	map {
	    $_=~/(\w+?)\:(\w+?)\:(\w+?)\:(.*)/; chomp;
	    if ($3 eq 'library') {
		$hostdomains{$1}=$2;
		$hostips{$1}=$4;
	    }
	} <$fh>;
    }
}

my $diropendb = "";
my $domain = "";

# ----------------------------- Handling routine called via Apache and mod_perl
sub handler {
    my $r = shift;
    untie %hash;
    &get_unprocessed_cgi();

    $r->content_type('text/html');
    $r->send_http_header;
    return OK if $r->header_only;

    $domain  = $r->dir_config('lonDefDomain');

    $diropendb = "/home/httpd/perl/tmp/$domain\_$ENV{'user.name'}_indexer.db";

    if ($ENV{'form.launch'} eq '1') {
	if (tie(%hash,'GDBM_File',$diropendb,&GDBM_WRCREAT,0640)) {
	    &start_fresh_session();
	    untie %hash;
	}
	else {
	    $r->print('<html><head></head><body>Unable to tie hash to db '.
		      'file</body></html>');
	    return OK;
	}
    }

# ----------------------------------- configure dynamic components of interface
    my $hidden='';
    if ($ENV{'form.catalogmode'} eq 'interactive') {
	$hidden="<input type='hidden' name='catalogmode' value='interactive'>".
	    "\n";
        $closebutton="<input type='button' name='close' value='CLOSE' ".
	    "onClick='self.close()'>"."\n";
    }
    elsif ($ENV{'form.catalogmode'} eq 'groupsearch') {
	$hidden=<<END;
<input type='hidden' name='catalogmode' value='groupsearch'>
END
        $closebutton=<<END;
<input type='button' name='close' value='CLOSE' onClick='self.close()'>
END
        $importbutton=<<END;
<input type='button' name='import' value='IMPORT'
onClick='javascript:select_group()'>
END
    }

# ------------------------------------------------------ Determine current user
    $yourself=$ENV{'user.name'}.'@'.$ENV{'user.domain'};

# --- Now, depending on the interface actions, do one of three things here:
# --- 1. a basic search
# --- 2. an advanced search
# --- 3. output a search interface

# ----------------------------------- See if a search invocation should be done
    if ($ENV{'form.basicsubmit'} eq 'SEARCH') {
	untie %hash; return &basicsearch($r,\%ENV);
    }
    elsif ($ENV{'form.advancedsubmit'} eq 'SEARCH') {
	untie %hash; return &advancedsearch($r,\%ENV);
    }

# ----------------------------- Else, begin building search interface to output
    $scrout=''; # building a part of screen output
    $scrout.=&searchphrasefield('Limit by title','title',
			$ENV{'form.title'});

    $scrout.=&searchphrasefield('Limit by author','author',
			$ENV{'form.author'});

    $scrout.=&searchphrasefield('Limit by subject','subject',
			$ENV{'form.subject'});

    $scrout.=&searchphrasefield('Limit by keywords','keywords',
			$ENV{'form.keywords'});

    $scrout.=&searchphrasefield('Limit by URL','url',
			$ENV{'form.url'});

#    $scrout.=&searchphrasefield('Limit by version','version',
#			$ENV{'form.version'});

    $scrout.=&searchphrasefield('Limit by notes','notes',
			$ENV{'form.notes'});

    $scrout.=&searchphrasefield('Limit by abstract','abstract',
			$ENV{'form.abstract'});

    $ENV{'form.mime'}='notxxx' unless length($ENV{'form.mime'});
    $scrout.=&selectbox('Limit by MIME type','mime',
			$ENV{'form.mime'},%mimetag);

    $ENV{'form.language'}='any' unless length($ENV{'form.language'});

    $scrout.=&selectbox('Limit by language','language',
			$ENV{'form.language'},%language);
    

# ------------------------------------------------ Compute date selection boxes
    $scrout.=<<CREATIONDATESTART;
<p>
<font color="#800000" face="helvetica"><b>LIMIT BY CREATION DATE RANGE:</b>
</font>
<br />
between:
CREATIONDATESTART
    $scrout.=&dateboxes('creationdatestart',1,1,1976,
			$ENV{'form.creationdatestart_month'},
			$ENV{'form.creationdatestart_day'},
			$ENV{'form.creationdatestart_year'},
			);
    $scrout.=<<CREATIONDATEEND;
and:
CREATIONDATEEND
    $scrout.=&dateboxes('creationdateend',12,31,2051,
			$ENV{'form.creationdateend_month'},
			$ENV{'form.creationdateend_day'},
			$ENV{'form.creationdateend_year'},
			);
    $scrout.="</p>";

    $scrout.=<<LASTREVISIONDATESTART;
<p>
<font color="#800000" face="helvetica"><b>LIMIT BY LAST REVISION DATE RANGE:
</b></font>
<br />between:
LASTREVISIONDATESTART
    $scrout.=&dateboxes('lastrevisiondatestart',1,1,1976,
			$ENV{'form.lastrevisiondatestart_month'},
			$ENV{'form.lastrevisiondatestart_day'},
			$ENV{'form.lastrevisiondatestart_year'},
			);
    $scrout.=<<LASTREVISIONDATEEND;
and:
LASTREVISIONDATEEND
    $scrout.=&dateboxes('lastrevisiondateend',12,31,2051,
			$ENV{'form.lastrevisiondateend_month'},
			$ENV{'form.lastrevisiondateend_day'},
			$ENV{'form.lastrevisiondateend_year'},
			);
    $scrout.='</p>';

    $scrout.=&searchphrasefield('Limit by publisher/owner','owner',
				$ENV{'form.owner'});

    $ENV{'form.copyright'}='any' unless length($ENV{'form.copyright'});
    $scrout.=&selectbox('Limit by copyright/distribution','copyright',
			$ENV{'form.copyright'},%cprtag);

# ------------------------------------------- Compute customized metadata field
    $scrout.=<<CUSTOMMETADATA;
<p>
<font color="#800000" face="helvetica"><b>LIMIT BY SPECIAL METADATA FIELDS:</b>
</font>
For resource-specific metadata, enter in an expression in the form of 
<i>key</i>=<i>value</i> separated by operators such as AND, OR or NOT.<br />
<b>Example:</b> grandmother=75 OR grandfather=85
<br />
CUSTOMMETADATA
$scrout.=&simpletextfield('custommetadata',$ENV{'form.custommetadata'});
$scrout.=' <i>initial users of this system do not need to worry about this option</i>';

    $scrout.=<<CUSTOMSHOW;
<p>
<font color="#800000" face="helvetica"><b>SHOW SPECIAL METADATA FIELDS:</b>
</font>
Enter in a space-separated list of special metadata fields to show
in a fielded listing for each record result.
<br />
CUSTOMSHOW
$scrout.=&simpletextfield('customshow',$ENV{'form.customshow'});
$scrout.=' <i>initial users of this system do not need to worry about this option</i>';

# ---------------------------------------------------------------- Print screen
    $r->print(<<ENDDOCUMENT);
<html>
<head>
<title>The LearningOnline Network with CAPA</title>
<script type="text/javascript">
    function openhelp(val) {
	openhelpwin=open('/adm/help/searchcat.html','helpscreen',
	     'scrollbars=1,width=400,height=300');
	openhelpwin.focus();
    }
</script>
</head>
<body bgcolor="#FFFFFF">
<img align='right' src='/adm/lonIcons/lonlogos.gif' />
<h1>Search Catalog</h1>
<form method="post" action="/adm/searchcat">
$hidden
<hr />
<h3>Basic Search</h3>
<p>
Enter terms or phrases separated by search operators
such as AND, OR, or NOT then press SEARCH below.  Terms should be specific
to the title, author, subject, notes, or abstract information associated
with a resource.
<br />
ENDDOCUMENT
    $r->print(&simpletextfield('basicexp',$ENV{'form.basicexp'}));
    $r->print(' ');
    $r->print(&simplecheckbox('titleonly',$ENV{'form.titleonly'}));
    $r->print('<font color="#800000">Title only</font> ');
#    $r->print(&simplecheckbox('allversions',$ENV{'form.allversions'}));
# <font color="#800000">Search historic archives</font>
    $r->print(<<ENDDOCUMENT);
<br />
<input type="submit" name="basicsubmit" value='SEARCH' />
<input type="reset" name="reset" value='RESET' />
$closebutton
$basicviewselect
<input type="button" value="HELP" onClick="openhelp()" />
</p>
<hr />
<h3>Advanced Search</h3>
$scrout
<p>
<input type="submit" name="advancedsubmit" value='SEARCH' />
<input type="reset" name="reset" value='RESET' />
$closebutton
$advancedviewselect
<input type="button" value="HELP" onClick="openhelp()" />
</p>
</form>
</body>
</html>
ENDDOCUMENT
    return OK;
} 

# ----------- grab unprocessed CGI variables that may have been appended to URL
sub get_unprocessed_cgi {
    map {
       my ($name, $value) = split(/=/,$_);
       $value =~ tr/+/ /;
       $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
       if ($name eq 'catalogmode' or $name eq 'launch' or $name eq 'acts') {
	   $ENV{'form.'.$name}=$value;
       }
    } (split(/&/,$ENV{'QUERY_STRING'}));
}

# ------------------------------------------------------------- make persistent
sub make_persistent {
    my $persistent='';
    
    map {
	if (/^form\./ && !/submit/) {
	    my $name=$_;
	    my $key=$name;
	    $ENV{$key}=~s/\'//g; # do not mess with html field syntax
	    $name=~s/^form\.//;
	    $persistent.=<<END;
<input type='hidden' name='$name' value='$ENV{$key}' />
END
        }
    } (keys %ENV);
    return $persistent;
}

# --------------------------------------------------------- Various form fields

sub simpletextfield {
    my ($name,$value)=@_;
    return '<input type=text name=\''.$name.
	   '\' size=20 value=\''.$value.'\' />';
}

sub simplecheckbox {
    my ($name,$value)=@_;
    my $checked='';
    $checked="CHECKED" if $value eq 'on';
    return '<input type=checkbox name=\''.$name.'\' '. $checked . '>';
}

sub searchphrasefield {
    my ($title,$name,$value)=@_;
    my $instruction=<<END;
Enter terms or phrases separated by search operators such
as AND, OR, or NOT.
END
    my $uctitle=uc($title);
    return "\n<p><font color=\"#800000\" face=\"helvetica\"><b>$uctitle:</b>".
	   "</FONT> $instruction<br />".
           '<input type=text name="'.$name.'" size=80 value=\''.$value.'\'>';
}

sub dateboxes {
    my ($name,$defaultmonth,$defaultday,$defaultyear,
	$currentmonth,$currentday,$currentyear)=@_;
    ($defaultmonth,$defaultday,$defaultyear)=('','','');
    my $month=<<END;
<select name="${name}_month">
<option value='$defaultmonth'> </option>
<option value="1">January</option>
<option value="2">February</option>
<option value="3">March</option>
<option value="4">April</option>
<option value="5">May</option>
<option value="6">June</option>
<option value="7">July</option>
<option value="8">August</option>
<option value="9">September</option>
<option value="10">October</option>
<option value="11">November</option>
<option value="12">December</option>
</select>
END
    $month=~s/(\"$currentmonth\")/$1 SELECTED/ if length($currentmonth);
    my $day=<<END;
<select name="${name}_day">
<option value='$defaultday'> </option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
<option value="6">6</option>
<option value="7">7</option>
<option value="8">8</option>
<option value="9">9</option>
<option value="10">10</option>
<option value="11">11</option>
<option value="12">12</option>
<option value="13">13</option>
<option value="14">14</option>
<option value="15">15</option>
<option value="16">16</option>
<option value="17">17</option>
<option value="18">18</option>
<option value="19">19</option>
<option value="20">20</option>
<option value="21">21</option>
<option value="22">22</option>
<option value="23">23</option>
<option value="24">24</option>
<option value="25">25</option>
<option value="26">26</option>
<option value="27">27</option>
<option value="28">28</option>
<option value="29">29</option>
<option value="30">30</option>
<option value="31">31</option>
</select>
END
    $day=~s/(\"$currentday\")/$1 SELECTED/ if length($currentday);
    my $year=<<END;
<select name="${name}_year">
<option value='$defaultyear'> </option>
<option value="1976">1976</option>
<option value="1977">1977</option>
<option value="1978">1978</option>
<option value="1979">1979</option>
<option value="1980">1980</option>
<option value="1981">1981</option>
<option value="1982">1982</option>
<option value="1983">1983</option>
<option value="1984">1984</option>
<option value="1985">1985</option>
<option value="1986">1986</option>
<option value="1987">1987</option>
<option value="1988">1988</option>
<option value="1989">1989</option>
<option value="1990">1990</option>
<option value="1991">1991</option>
<option value="1992">1992</option>
<option value="1993">1993</option>
<option value="1994">1994</option>
<option value="1995">1995</option>
<option value="1996">1996</option>
<option value="1997">1997</option>
<option value="1998">1998</option>
<option value="1999">1999</option>
<option value="2000">2000</option>
<option value="2001">2001</option>
<option value="2002">2002</option>
<option value="2003">2003</option>
<option value="2004">2004</option>
<option value="2005">2005</option>
<option value="2006">2006</option>
<option value="2007">2007</option>
<option value="2008">2008</option>
<option value="2009">2009</option>
<option value="2010">2010</option>
<option value="2011">2011</option>
<option value="2012">2012</option>
<option value="2013">2013</option>
<option value="2014">2014</option>
<option value="2015">2015</option>
<option value="2016">2016</option>
<option value="2017">2017</option>
<option value="2018">2018</option>
<option value="2019">2019</option>
<option value="2020">2020</option>
<option value="2021">2021</option>
<option value="2022">2022</option>
<option value="2023">2023</option>
<option value="2024">2024</option>
<option value="2025">2025</option>
<option value="2026">2026</option>
<option value="2027">2027</option>
<option value="2028">2028</option>
<option value="2029">2029</option>
<option value="2030">2030</option>
<option value="2031">2031</option>
<option value="2032">2032</option>
<option value="2033">2033</option>
<option value="2034">2034</option>
<option value="2035">2035</option>
<option value="2036">2036</option>
<option value="2037">2037</option>
<option value="2038">2038</option>
<option value="2039">2039</option>
<option value="2040">2040</option>
<option value="2041">2041</option>
<option value="2042">2042</option>
<option value="2043">2043</option>
<option value="2044">2044</option>
<option value="2045">2045</option>
<option value="2046">2046</option>
<option value="2047">2047</option>
<option value="2048">2048</option>
<option value="2049">2049</option>
<option value="2050">2050</option>
<option value="2051">2051</option>
</select>
END
    $year=~s/(\"$currentyear\")/$1 SELECTED/ if length($currentyear);
    return "$month$day$year";
}

sub selectbox {
    my ($title,$name,$value,%options)=@_;
    my $uctitle=uc($title);
    my $selout="\n<p><font color=\"#800000\" face=\"helvetica\"><b>$uctitle:".
	"</b></font><br />".'<select name="'.$name.'">';
    map {
        $selout.='<option value=\''.$_.'\'';
        if ($_ eq $value) { $selout.=' selected'; }
        $selout.='>'.$options{$_}.'</option>';
    } sort keys %options;
    return $selout.'</select>';
}

# ----------------------------------------------- Performing an advanced search
sub advancedsearch {
    my ($r,$envhash)=@_;
    my %ENV=%{$envhash};

    my $fillflag=0;
    # Clean up fields for safety
    for my $field ('title','author','subject','keywords','url','version',
		   'creationdatestart_month','creationdatestart_day',
		   'creationdatestart_year','creationdateend_month',
		   'creationdateend_day','creationdateend_year',
		   'lastrevisiondatestart_month','lastrevisiondatestart_day',
		   'lastrevisiondatestart_year','lastrevisiondateend_month',
		   'lastrevisiondateend_day','lastrevisiondateend_year',
		   'notes','abstract','mime','language','owner',
		   'custommetadata','customshow') {
	$ENV{"form.$field"}=~s/[^\w\/\s\(\)\=\-\"\']//g;
    }

    # Check to see if enough information was filled in
    for my $field ('title','author','subject','keywords','url','version',
		   'notes','abstract','mime','language','owner',
		   'custommetadata') {
	if (&filled($ENV{"form.$field"})) {
	    $fillflag++;
	}
    }
    unless ($fillflag) {
	&output_blank_field_error($r);
	return OK;
    }


    # Turn the form input into a SQL-based query
    my $query='';

    my @queries;
    # Evaluate logical expression AND/OR/NOT phrase fields.
    foreach my $field ('title','author','subject','notes','abstract','url',
		       'keywords','version','owner') {
	if ($ENV{'form.'.$field}) {
	    push @queries,&build_SQL_query($field,$ENV{'form.'.$field});
	}
    }
    # Evaluate option lists
    if ($ENV{'form.language'} and $ENV{'form.language'} ne 'any') {
	push @queries,"(language like \"$ENV{'form.language'}\")";
    }
    if ($ENV{'form.mime'} and $ENV{'form.mime'} ne 'any') {
	push @queries,"(mime like \"$ENV{'form.mime'}\")";
    }
    if ($ENV{'form.copyright'} and $ENV{'form.copyright'} ne 'any') {
	push @queries,"(copyright like \"$ENV{'form.copyright'}\")";
    }
    # Evaluate date windows
    my $datequery=&build_date_queries(
			$ENV{'form.creationdatestart_month'},
			$ENV{'form.creationdatestart_day'},
			$ENV{'form.creationdatestart_year'},
			$ENV{'form.creationdateend_month'},
			$ENV{'form.creationdateend_day'},
			$ENV{'form.creationdateend_year'},
			$ENV{'form.lastrevisiondatestart_month'},
			$ENV{'form.lastrevisiondatestart_day'},
			$ENV{'form.lastrevisiondatestart_year'},
			$ENV{'form.lastrevisiondateend_month'},
			$ENV{'form.lastrevisiondateend_day'},
			$ENV{'form.lastrevisiondateend_year'},
			);
    # Test to see if date windows are legitimate
    if ($datequery=~/^Incorrect/) {
	&output_date_error($r,$datequery);
	return OK;
    }
    elsif ($datequery) {
	push @queries,$datequery;
    }

    # Process form information for custom metadata querying
    my $customquery='';
    if ($ENV{'form.custommetadata'}) {
	$customquery=&build_custommetadata_query('custommetadata',
				      $ENV{'form.custommetadata'});
    }
    my $customshow='';
    if ($ENV{'form.customshow'}) {
	$customshow=$ENV{'form.customshow'};
	$customshow=~s/[^\w\s]//g;
	my @fields=split(/\s+/,$customshow);
	$customshow=join(" ",@fields);
    }
    # Send query statements over the network to be processed by either the SQL
    # database or a recursive scheme of 'grep'-like actions (for custom
    # metadata).
    if (@queries) {
	$query=join(" AND ",@queries);
	$query="select * from metadata where $query";
	my $reply; # reply hash reference
	unless ($customquery or $customshow) {
	    $reply=&Apache::lonnet::metadata_query($query);
	}
	else {
	    $reply=&Apache::lonnet::metadata_query($query,
						   $customquery,$customshow);
	}
	&output_results('Advanced',$r,$envhash,$customquery,$reply);
    }
    elsif ($customquery) {
	my $reply; # reply hash reference
	$reply=&Apache::lonnet::metadata_query('',
					       $customquery,$customshow);
	&output_results('Advanced',$r,$envhash,$customquery,$reply);
    }
    # should not get to this point
    return 'Error.  Should not have gone to this point.';
}

# --------------------------------------------------- Performing a basic search
sub basicsearch {
    my ($r,$envhash)=@_;
    my %ENV=%{$envhash};
    # Clean up fields for safety
    for my $field ('basicexp') {
	$ENV{"form.$field"}=~s/[^\w\s\(\)\-]//g;
    }

    # Check to see if enough is filled in
    unless (&filled($ENV{'form.basicexp'})) {
	&output_blank_field_error($r);
	return OK;
    }

    # Build SQL query string based on form page
    my $query='';
    my $concatarg=join(',"    ",',
		       ('title', 'author', 'subject', 'notes', 'abstract'));
    $concatarg='title' if $ENV{'form.titleonly'};

    $query=&build_SQL_query('concat('.$concatarg.')',$ENV{'form.'.'basicexp'});

    # Get reply (either a hash reference to filehandles or bad connection)
    my $reply=&Apache::lonnet::metadata_query('select * from metadata where '.$query);

    # Output search results

    &output_results('Basic',$r,$envhash,$query,$reply);

    return OK;
}

# ------------------------------------------------------------- build_SQL_query
sub build_SQL_query {
    my ($field_name,$logic_statement)=@_;
    my $q=new Text::Query('abc',
			  -parse => 'Text::Query::ParseAdvanced',
			  -build => 'Text::Query::Build');
    $q->prepare($logic_statement);
    my $matchexp=${$q}{'matchexp'}; chomp $matchexp;
    my $sql_query=&recursive_SQL_query_build($field_name,$matchexp);
    return $sql_query;
}

# ------------------------------------------------- build custom metadata query
sub build_custommetadata_query {
    my ($field_name,$logic_statement)=@_;
    my $q=new Text::Query('abc',
			  -parse => 'Text::Query::ParseAdvanced',
			  -build => 'Text::Query::BuildAdvancedString');
    $q->prepare($logic_statement);
    my $matchexp=${$q}{'-parse'}{'-build'}{'matchstring'};
    # quick fix to change literal into xml tag-matching
    # will eventually have to write a separate builder module
    my $oldmatchexp=$matchexp;
    $matchexp=~s/(\w+)\\\=([\w\\\+]+)/\\\<$1\\\>\[\^\\\<\]\*$2\[\^\\\<\]\*\\\<\\\/$1\\\>/g;
    return $matchexp;
}

# - Recursively parse a reverse notation expression into a SQL query expression
sub recursive_SQL_query_build {
    my ($dkey,$pattern)=@_;
    my @matches=($pattern=~/(\[[^\]|\[]*\])/g);
    return $pattern unless @matches;
    foreach my $match (@matches) {
	$match=~/\[ (\w+)\s(.*) \]/;
	my ($key,$value)=($1,$2);
	my $replacement='';
	if ($key eq 'literal') {
	    $replacement="($dkey like \"\%$value\%\")";
	}
	elsif ($key eq 'not') {
	    $value=~s/like/not like/;
#	    $replacement="($dkey not like $value)";
	    $replacement="$value";
	}
	elsif ($key eq 'and') {
	    $value=~/(.*[\"|\)]) ([|\(|\^].*)/;
	    $replacement="($1 AND $2)";
	}
	elsif ($key eq 'or') {
	    $value=~/(.*[\"|\)]) ([|\(|\^].*)/;
	    $replacement="($1 OR $2)";
	}
	substr($pattern,
	       index($pattern,$match),
	       length($match),
	       $replacement
	       );
    }
    &recursive_SQL_query_build($dkey,$pattern);
}

# ------------------------------------------------------------ Build date query
sub build_date_queries {
    my ($cmonth1,$cday1,$cyear1,$cmonth2,$cday2,$cyear2,
	$lmonth1,$lday1,$lyear1,$lmonth2,$lday2,$lyear2)=@_;
    my @queries;
    if ($cmonth1 or $cday1 or $cyear1 or $cmonth2 or $cday2 or $cyear2) {
	unless ($cmonth1 and $cday1 and $cyear1 and
		$cmonth2 and $cday2 and $cyear2) {
	    return "Incorrect entry for the creation date.  You must specify ".
		   "a starting month, day, and year and an ending month, ".
		   "day, and year.";
	}
	my $cnumeric1=sprintf("%d%2d%2d",$cyear1,$cmonth1,$cday1);
	$cnumeric1+=0;
	my $cnumeric2=sprintf("%d%2d%2d",$cyear2,$cmonth2,$cday2);
	$cnumeric2+=0;
	if ($cnumeric1>$cnumeric2) {
	    return "Incorrect entry for the creation date.  The starting ".
		   "date must occur before the ending date.";
	}
	my $cquery="(creationdate BETWEEN '$cyear1-$cmonth1-$cday1' AND '".
	           "$cyear2-$cmonth2-$cday2 23:59:59')";
	push @queries,$cquery;
    }
    if ($lmonth1 or $lday1 or $lyear1 or $lmonth2 or $lday2 or $lyear2) {
	unless ($lmonth1 and $lday1 and $lyear1 and
		$lmonth2 and $lday2 and $lyear2) {
	    return "Incorrect entry for the last revision date.  You must ".
		   "specify a starting month, day, and year and an ending ".
		   "month, day, and year.";
	}
	my $lnumeric1=sprintf("%d%2d%2d",$lyear1,$lmonth1,$lday1);
	$lnumeric1+=0;
	my $lnumeric2=sprintf("%d%2d%2d",$lyear2,$lmonth2,$lday2);
	$lnumeric2+=0;
	if ($lnumeric1>$lnumeric2) {
	    return "Incorrect entry for the last revision date.  The ".
		   "starting date must occur before the ending date.";
	}
	my $lquery="(lastrevisiondate BETWEEN '$lyear1-$lmonth1-$lday1' AND '".
	           "$lyear2-$lmonth2-$lday2 23:59:59')";
	push @queries,$lquery;
    }
    if (@queries) {
	return join(" AND ",@queries);
    }
    return '';
}

# ----------------------------- format and output results based on a reply list
# There are two windows that this function writes to.  The main search
# window ("srch") has a listing of the results.  A secondary window ("popwin")
# gives the status of the network search (time elapsed, number of machines
# contacted, etc.)
sub output_results {
    my $fnum; # search result counter
    my ($mode,$r,$envhash,$query,$replyref)=@_;
    my %ENV=%{$envhash};
    my %rhash=%{$replyref};
    my $compiledresult='';
    my $timeremain=300;
    my $elapsetime=0;
    my $resultflag=0;
    my $tflag=1;

    # make query information persistent to allow for subsequent revision
    my $persistent=&make_persistent();

    # output beginning of search page
	$r->print(<<BEGINNING);
<html>
<head>
<title>The LearningOnline Network with CAPA</title>
BEGINNING

    # conditional output of script functions dependent on the mode in
    # which the search was invoked
        $r->print(<<SCRIPT) if $ENV{'form.catalogmode'} eq 'interactive';
<script type="text/javascript">
    function select_data(title,url) {
	changeTitle(title);
	changeURL(url);
	self.close();
    }
    function changeTitle(val) {
	if (opener.inf.document.forms.resinfo.elements.t) {
	    opener.inf.document.forms.resinfo.elements.t.value=val;
	}
    }
    function changeURL(val) {
	if (opener.inf.document.forms.resinfo.elements.u) {
	    opener.inf.document.forms.resinfo.elements.u.value=val;
	}
    }
</script>
SCRIPT
        $r->print(<<SCRIPT) if $ENV{'form.catalogmode'} eq 'groupsearch';
<script type="text/javascript">
    function select_data(title,url) {
//	alert('DEBUG: Should be storing '+title+' and '+url);
    }
    function queue(val) {
	if (eval("document.forms.results.returnvalues["+val+"].checked")) {
	    document.forms.results.acts.value+='1a'+val+'b';
	}
	else {
	    document.forms.results.acts.value+='0a'+val+'b';
	}
    }
    function select_group() {
	window.location="/adm/groupsort?catalogmode=groupsearch&acts="+
	    document.forms.results.acts.value;
    }
</script>
SCRIPT
        $r->print(<<SCRIPT);
<script type="text/javascript">
    function displayinfo(val) {
	popwin.document.forms.popremain.sdetails.value=val;
    }
    function openhelp(val) {
	openhelpwin=open('/adm/help/searchcat.html','helpscreen',
	     'scrollbars=1,width=400,height=300');
	openhelpwin.focus();
    }
    function abortsearch(val) {
	openhelpwin=open('/adm/help/searchcat.html','helpscreen',
	     'scrollbars=1,width=400,height=300');
	openhelpwin.focus();
    }
</script>
SCRIPT
    $r->rflush();

    # begin showing the cataloged results
    $r->print(<<CATALOGBEGIN);
</head>
<body bgcolor="#ffffff">
<img align=right src=/adm/lonIcons/lonlogos.gif>
<h1>Search Catalog</h1>
CATALOGBEGIN
        $r->print(<<CATALOGCONTROLS);
<form name='results' method="post" action="/adm/searchcat">
<input type='hidden' name='acts' value='' />
<input type='button' value='Revise search request'
onClick='this.form.submit();' />
$importbutton
$closebutton
$persistent
<hr />
<h3>Search Query</h3>
CATALOGCONTROLS
    if ($mode eq 'Basic') {
	$r->print(<<RESULTS);
<p>
<b>Basic search:</b> $ENV{'form.basicexp'}
</p>
RESULTS
    }
    elsif ($mode eq 'Advanced') {
	$r->print(<<RESULTS);
<p>
<b>Advanced search</b>
$query
</p>
RESULTS
    }
    $r->print('<h3>Search Results</h3>');
    $r->rflush();
    my $servernum=(keys %rhash)+0;

    # define server grid (shows status of multiple machines)
    my $hcinit;
    my $grid="'<br />'+";
    $grid.="\n";
    my $sn=1;
    for my $sk (sort keys %rhash) {
	# '<a href="
	$grid.="'<a href=\"";
	# javascript:displayinfo('+
	$grid.="javascript:opener.displayinfo('+";
	# "'"+'key
	$grid.="\"'\"+'";
	$grid.=$sk;
	my $hc;
	if ($rhash{$sk} eq 'con_lost') {
	    $hc="!!!BAD CONNECTION, CONTACT SYSTEM ADMINISTRATOR!!!";
	}
	else {
	    $hc="'+\"'\"+\"+hc['$sk']+\"+\"'\"+'";
	    $hcinit.="hc[\"$sk\"]=\"not yet connected...\";";
	}
	$grid.=" hitcount=".$hc;
	$grid.=" domain=".$hostdomains{$sk};
	$grid.=" IP=".$hostips{$sk};
	# '+"'"+'">'+
	$grid.="'+\"'\"+')\">'+";
	$grid.="\n";
	$grid.="'<img border=\"0\" name=\"img".$sn."\"".
	    " src=\"/adm/lonIcons/srvnull.gif\" alt=\"".$sk."\" /></a>'+\n";
	$grid.="'<br />'+\n" unless $sn%10;
        $sn++;
    }
	    $r->print(<<ENDPOP);
<script type="text/javascript">
    popwin=open('','popwin','scrollbars=1,width=400,height=200');
    popwin.focus();
    popwin.document.writeln('<'+'html>');
    popwin.document.writeln('<'+'head>');
    popwin.document.writeln('<'+'script>');
    popwin.document.writeln('hc=new Array();$hcinit');
    popwin.document.writeln('<'+'/script>');
    popwin.document.writeln('<'+'/head>'+
        '<'+'body bgcolor="#FFFFFF">'+
	'<'+'image name="whirly" align="right" src="/adm/lonIcons/'+
	'lonanim.gif" '+
	'alt="animated logo" />'+
	'<'+'h3>Search Results Progress<'+'/h3>'+
        '<'+'form name="popremain">'+
        '<'+'tt>'+
	'<'+'br clear="all"/><i>PLEASE BE PATIENT</i>'+
	'<'+'br />SCANNING $servernum SERVERS'+
	'<'+'br clear="all" />Number of record hits found '+
	'<'+'input type="text" size="10" name="numhits"'+
	' value="0" />'+
	'<'+'br clear="all" />Time elapsed '+
	'<'+'input type="text" size="10" name="elapsetime"'+
	' value="0" />'+
	'<'+'br />'+
	'SERVER GRID (click on any cell for details)'+
        $grid
        '<'+'br />'+
	'Server details '+
	'<'+'input type="text" size="25" name="sdetails"'+
	' value="" />'+
	'<'+'br />'+
	' <'+'input type="button" name="button"'+
	' value="abort search and view current results" '+
	' onClick="javascript:opener.abortsearch()" />'+
	' <'+'input type="button" name="button"'+
	' value="help" onClick="javascript:opener.openhelp()" />'+
	'<'+'/tt>'+
        '<'+'/form>'+
        '<'+'/body><'+'/html>');
    popwin.document.close();
</script>
ENDPOP
    $r->rflush();

    my $servercount=0;
    my $hitcountsum=0;
    my $bloop=$servernum;
    my %orkey;
  BLOOP: while(1) {
      my $sn=0;
      last BLOOP unless $bloop;
    RLOOP: foreach my $rkey (sort keys %rhash) {
	$sn++;
	next RLOOP if $orkey{$rkey};
	$servercount++;
	$tflag=1;
	$compiledresult='';
	my $hostname=$rkey;
	my $reply=$rhash{$rkey};
	my @results;
	
	my $replyfile='';

	if ($reply eq 'con_lost') {
	    $r->print('<script type="text/javascript">popwin.document.img'.
		      $sn.'.'.
		      'src="/adm/lonIcons/srvbad.gif";</script>'.
		      "\n");
	    $r->rflush();
	    $bloop--;
	    $orkey{$rkey}=1;
	}
	else {
	    $reply=~/^([\.\w]+)$/; # must do since 'use strict' checks for tainting
	    $replyfile=$r->dir_config('lonDaemons').'/tmp/'.$1;
	    $reply=~/(.*?)\_/;
	    {
		my $temp=0;
	      WLOOP: while (1) {
		  if (-e $replyfile && $tflag) {
		      $r->print('<script type="text/javascript">'.
				'popwin.document.img'.$sn.'.'.
				'src="/adm/lonIcons/srvhalf.gif";</script>'.
				"\n");
		      $r->rflush();
		      $r->print('<script type="text/javascript">'.
				'popwin.hc["'.$rkey.'"]='.
				'"still transferring..."'.';</script>'.
				"\n");
		      $r->rflush();
		      $tflag=0;
		  }
		  last WLOOP if $temp>1;
		  if (-e "$replyfile.end") {
		      $bloop--;
		      $orkey{$rkey}=1;
		      if (-s $replyfile) {
			  $r->print('<script type="text/javascript">'.
				    'popwin.document.img'.$sn.'.'.
				    'src="/adm/lonIcons/srvgood.gif";'.
				    '</script>'."\n");
			  $r->rflush();
			  my $fh=Apache::File->new($replyfile) or 
			      ($r->print('ERROR: file '.
					 $replyfile.' cannot be opened') and
			       return OK);
			  @results=<$fh> if $fh;
			  $hitcount{$rkey}=@results+0;
			  $r->print('<script type="text/javascript">'.
				    'popwin.hc["'.$rkey.'"]='.
				    $hitcount{$rkey}.';</script>'.
				    "\n");
			  $r->rflush();
			  $hitcountsum+=$hitcount{$rkey};
			  $r->print('<script type="text/javascript">'.
				    'popwin.document.forms.popremain.'.
				    'numhits.value='.$hitcountsum.
				    ';</script>'.
				    "\n");
			  $r->rflush();
		      }
		      else {
			  $r->print('<script type="text/javascript">'.
				    'popwin.document.img'.$sn.'.'.
				    'src="/adm/lonIcons/srvempty.gif";'.
				    '</script>'.
				    "\n");
			  $r->rflush();
			  $r->print('<script type="text/javascript">'.
				    'popwin.hc["'.$rkey.'"]=0'.
				    ';</script>'.
				    "\n");
			  $r->rflush();
		      }
		      last WLOOP;
		  }
		  last WLOOP unless $timeremain;
		  sleep 1;
		  $timeremain--;
		  $elapsetime++;
		  $r->print('<script type="text/javascript">'.
			    'popwin.document.popremain.elapsetime.'.
			    'value="'.$elapsetime.'";</script>'."\n");
		  $r->rflush();
		  $temp++;
	      }
	    }
	    $r->print('<script type="text/javascript">'.
		      'popwin.document.whirly.'.
		      'src="'.'/adm/lonIcons/lonanimend.gif'.
		      '";</script>'."\n");
	    $r->rflush();
	}
	my $customshow='';
	my $extrashow='';
	my @customfields;
	if ($ENV{'form.customshow'}) {
	    $customshow=$ENV{'form.customshow'};
	    $customshow=~s/[^\w\s]//g;
	    my @fields=map {"<font color=\"#008000\">$_:</font><!-- $_ -->"} 
	    split(/\s+/,$customshow);
	    @customfields=split(/\s+/,$customshow);
	    if ($customshow) {
		$extrashow="<ul><li>".join("</li><li>",@fields)."</li></ul>\n";
	    }
	}
	my $customdata='';
	my %customhash;
	foreach my $result (@results) {
	    if ($result=~/^(custom\=.*)$/) { # grab all custom metadata
		my $tmp=$result;
		$tmp=~s/^custom\=//;
		my ($k,$v)=map {&Apache::lonnet::unescape($_);
			    } split(/\,/,$tmp);
		$customhash{$k}=$v;
	    }
	}
	if (keys %hash) {
	    untie %hash;
	}
	if (tie(%hash,'GDBM_File',$diropendb,&GDBM_WRCREAT,0640)) {
	    if ($ENV{'form.launch'} eq '1') {
		&start_fresh_session();
	    }
	    foreach my $result (@results) {
		next if $result=~/^custom\=/;
		chomp $result;
		next unless $result;
		my @fields=map
		{&Apache::lonnet::unescape($_)}
		(split(/\,/,$result));
		my ($title,$author,$subject,$url,$keywords,$version,
		    $notes,$abstract,$mime,$lang,
		    $creationdate,$lastrevisiondate,$owner,$copyright)=@fields;

		unless ($ENV{'user.adv'}) {
		    $keywords='<i>- not displayed -</i>';
		    $fields[4]=$keywords;
		    $notes='<i>- not displayed -</i>';
		    $fields[6]=$notes;
		    $abstract='<i>- not displayed -</i>';
		    $fields[7]=$abstract;
		    $subject='<i>- not displayed -</i>';
		    $fields[2]=$subject;
		}

		my $shortabstract=$abstract;
		$shortabstract=substr($abstract,0,200).'...' if length($abstract)>200;
		$fields[7]=$shortabstract;
		my $shortkeywords=$keywords;
		$shortkeywords=substr($keywords,0,200).'...' if length($keywords)>200;
		$fields[4]=$shortkeywords;

		my $extrashow2=$extrashow;
		if ($extrashow) {
		    foreach my $field (@customfields) {
			my $value='';
			if ($customhash{$url}=~/\<${field}[^\>]*\>(.*?)\<\/${field}[^\>]*\>/s) {
		            $value=$1;
			}
		        $extrashow2=~s/\<\!\-\- $field \-\-\>/ $value/g;
	            }
                }
	
	        $compiledresult.=<<END if $compiledresult or $servercount!=$servernum;
<hr align='left' width='200' noshade />
END
                $compiledresult.=<<END;
<p>
END
                $compiledresult.=<<END if $ENV{'form.catalogmode'} eq 'interactive';
<font size='-1'><INPUT TYPE="button" NAME="returnvalues" VALUE="SELECT"
onClick="javascript:select_data('$title','$url')">
</font>
<br />
END
                if ($ENV{'form.catalogmode'} eq 'groupsearch') {
		    $fnum+=0;
		    $hash{"pre_${fnum}_link"}=$url;
		    $hash{"pre_${fnum}_title"}=$title;
		    $compiledresult.=<<END;
<font size='-1'><input type="checkbox" name="returnvalues" value="SELECT"
onClick="javascript:queue($fnum)" />
</font>
<br />
END
# <input type="hidden" name="title$fnum" value="$title" />
# <input type="hidden" name="url$fnum" value="$url" />
                    $fnum++;
		}
	        my $httphost=$ENV{'HTTP_HOST'};

	        my $viewselect;
	        if ($mode eq 'Basic') {
		    $viewselect=$ENV{'form.basicviewselect'};
		}
	        elsif ($mode eq 'Advanced') {
		    $viewselect=$ENV{'form.advancedviewselect'};
		}

	        if ($viewselect eq 'Detailed Citation View') {
		    $compiledresult.=&detailed_citation_view(@fields,
						 $hostname,$httphost,
						 $extrashow2);
		}
                elsif ($viewselect eq 'Summary View') {
		    $compiledresult.=&summary_view(@fields,$hostname,$httphost,
				       $extrashow2);
	        }
                elsif ($viewselect eq 'Fielded Format') {
		    $compiledresult.=&fielded_format_view(@fields,$hostname,
					      $httphost,$extrashow2);
	        }
                elsif ($viewselect eq 'XML/SGML') {
		    $compiledresult.=&xml_sgml_view(@fields,$hostname,$httphost,
					$extrashow2);
		}
    
            }

            untie %hash;
        }
        else {
	    $r->print('<html><head></head><body>Unable to tie hash to db '.
		  'file</body></html>');
	}
	if ($compiledresult) {
	    $resultflag=1;
	}

	$r->print(<<RESULTS);
$compiledresult
RESULTS
        my $percent=sprintf('%3.0f',($servercount/$servernum*100));
    }
  }
    unless ($resultflag) {
        $r->print("\nThere were no results that matched your query\n");
    }
#    $r->print('<script type="text/javascript">'.'popwin.close()</script>'."\n"); $r->rflush(); 
    $r->print(<<RESULTS);
</body>
</html>
RESULTS
}

# ------------------------------------------------------ Detailed Citation View
sub detailed_citation_view {
    my ($title,$author,$subject,$url,$keywords,$version,
	$notes,$shortabstract,$mime,$lang,
	$creationdate,$lastrevisiondate,$owner,$copyright,
	$hostname,$httphost,$extrashow)=@_;
    my $result=<<END;
<i>$owner</i>, last revised $lastrevisiondate
<h3><A HREF="http://$httphost$url" TARGET='search_preview'>$title</A></h3>
<h3>$author</h3>
</p>
<p>
<b>Subject:</b> $subject<br />
<b>Keyword(s):</b> $keywords<br />
<b>Notes:</b> $notes<br />
<b>MIME Type:</b> $mimetag{$mime}<br />
<b>Language:</b> $language{$lang}<br />
<b>Copyright/Distribution:</b> $cprtag{$copyright}<br />
</p>
$extrashow
<p>
$shortabstract
</p>
END
    return $result;
}

# ---------------------------------------------------------------- Summary View
sub summary_view {
    my ($title,$author,$subject,$url,$keywords,$version,
	$notes,$shortabstract,$mime,$lang,
	$creationdate,$lastrevisiondate,$owner,$copyright,
	$hostname,$httphost,$extrashow)=@_;
    my $result=<<END;
<a href="http://$httphost$url" TARGET='search_preview'>$author</a><br />
$title<br />
$owner -- $lastrevisiondate<br />
$cprtag{$copyright}<br />
$extrashow
</p>
END
    return $result;
}

# -------------------------------------------------------------- Fielded Format
sub fielded_format_view {
    my ($title,$author,$subject,$url,$keywords,$version,
	$notes,$shortabstract,$mime,$lang,
	$creationdate,$lastrevisiondate,$owner,$copyright,
	$hostname,$httphost,$extrashow)=@_;
    my $result=<<END;
<b>URL: </b> <A HREF="http://$httphost$url" TARGET='search_preview'>$url</A>
<br />
<b>Title:</b> $title<br />
<b>Author(s):</b> $author<br />
<b>Subject:</b> $subject<br />
<b>Keyword(s):</b> $keywords<br />
<b>Notes:</b> $notes<br />
<b>MIME Type:</b> $mimetag{$mime}<br />
<b>Language:</b> $language{$lang}<br />
<b>Creation Date:</b> $creationdate<br />
<b>Last Revision Date:</b> $lastrevisiondate<br />
<b>Publisher/Owner:</b> $owner<br />
<b>Copyright/Distribution:</b> $cprtag{$copyright}<br />
<b>Repository Location:</b> $hostname<br />
<b>Abstract:</b> $shortabstract<br />
$extrashow
</p>
END
    return $result;
}

# -------------------------------------------------------------------- XML/SGML
sub xml_sgml_view {
    my ($title,$author,$subject,$url,$keywords,$version,
	$notes,$shortabstract,$mime,$lang,
	$creationdate,$lastrevisiondate,$owner,$copyright,
	$hostname,$httphost,$extrashow)=@_;
    my $result=<<END;
<pre>
&lt;LonCapaResource&gt;
&lt;url&gt;$url&lt;/url&gt;
&lt;title&gt;$title&lt;/title&gt;
&lt;author&gt;$author&lt;/author&gt;
&lt;subject&gt;$subject&lt;/subject&gt;
&lt;keywords&gt;$keywords&lt;/keywords&gt;
&lt;notes&gt;$notes&lt;/notes&gt;
&lt;mimeInfo&gt;
&lt;mime&gt;$mime&lt;/mime&gt;
&lt;mimetag&gt;$mimetag{$mime}&lt;/mimetag&gt;
&lt;/mimeInfo&gt;
&lt;languageInfo&gt;
&lt;language&gt;$lang&lt;/language&gt;
&lt;languagetag&gt;$language{$lang}&lt;/languagetag&gt;
&lt;/languageInfo&gt;
&lt;creationdate&gt;$creationdate&lt;/creationdate&gt;
&lt;lastrevisiondate&gt;$lastrevisiondate&lt;/lastrevisiondate&gt;
&lt;owner&gt;$owner&lt;/owner&gt;
&lt;copyrightInfo&gt;
&lt;copyright&gt;$copyright&lt;/copyright&gt;
&lt;copyrighttag&gt;$cprtag{$copyright}&lt;/copyrighttag&gt;
&lt;/copyrightInfo&gt;
&lt;repositoryLocation&gt;$hostname&lt;/repositoryLocation&gt;
&lt;shortabstract&gt;$shortabstract&lt;/shortabstract&gt;
&lt;/LonCapaResource&gt;
</pre>
$extrashow
END
    return $result;
}

# ---------------------------------------------------- see if a field is filled
sub filled {
    my ($field)=@_;
    if ($field=~/\S/ && $field ne 'any') {
	return 1;
    }
    else {
	return 0;
    }
}

# ---------------- Message to output when there are not enough fields filled in
sub output_blank_field_error {
    my ($r)=@_;
    # make query information persistent to allow for subsequent revision
    my $persistent=&make_persistent();

    $r->print(<<BEGINNING);
<html>
<head>
<title>The LearningOnline Network with CAPA</title>
BEGINNING
    $r->print(<<RESULTS);
</head>
<body bgcolor="#ffffff">
<img align='right' src='/adm/lonIcons/lonlogos.gif' />
<h1>Search Catalog</h1>
<form method="post" action="/adm/searchcat">
$persistent
<input type='button' value='Revise search request'
onClick='this.form.submit();' />
$closebutton
<hr />
<h3>Helpful Message</h3>
<p>
Incorrect search query due to blank entry fields.
You need to fill in the relevant
fields on the search page in order for a query to be
processed.
</p>
</body>
</html>
RESULTS
}

# ----------------------------------------------------------- Output date error
sub output_date_error {
    my ($r,$message)=@_;
    # make query information persistent to allow for subsequent revision
    my $persistent=&make_persistent();

    $r->print(<<BEGINNING);
<html>
<head>
<title>The LearningOnline Network with CAPA</title>
BEGINNING
    $r->print(<<RESULTS);
</head>
<body bgcolor="#ffffff">
<img align='right' src='/adm/lonIcons/lonlogos.gif' />
<h1>Search Catalog</h1>
<form method="post" action="/adm/searchcat">
$persistent
<input type='button' value='Revise search request'
onClick='this.form.submit();' />
$closebutton
<hr />
<h3>Helpful Message</h3>
<p>
$message
</p>
</body>
</html>
RESULTS
}

# --------- settings whenever the user causes the indexer window to be launched
sub start_fresh_session {
    delete $hash{'mode_catalog'};
    map {
        if ($_ =~ /^pre_/) {
            delete $hash{$_};
        }
        if ($_ =~ /^store/) {
	    delete $hash{$_};
	}
    } keys %hash;
}

1;

__END__