# ====================================================================
# Gossamer Threads Module Library - http://gossamer-threads.com/
#
#   GT::SQL::Search::STH
#   Author: Aki Mimoto
#   CVS Info : 087,071,086,086,085      
#   $Id: STH.pm,v 1.25 2004/08/28 03:53:46 jagerman Exp $
#
# Copyright (c) 2004 Gossamer Threads Inc.  All Rights Reserved.
# ====================================================================
#

package GT::SQL::Search::STH;
#--------------------------------------------------------------------------------
    use strict;
    use vars qw/@ISA $ATTRIBS $VERSION $DEBUG $ERRORS $ERROR_MESSAGE /;
    use GT::Base;

    @ISA    = ('GT::Base');
    $ATTRIBS = {
                '_debug'    => 0,
                'sth'       => undef,
                'results'   => {},
                'db'        => undef,
                'table'     => undef,
                'index'     => 0,
                'order'     => [],
                'sb'        => 'score',
                'so'        => '',
                'score_col' => 'SCORE',
                'score_sort'=> 0,
                'nh'        => 0,
                'mh'        => 0
    };
    $ERROR_MESSAGE = 'GT::SQL';
    $ERRORS        = {
        BADSB => 'Invalid character found in so: "%s"',
    };

sub init {
#--------------------------------------------------------------------------------
    my $self    = shift;

# setup the options
    $self->set(@_);

# correct a few of the values
    --$self->{nh} if $self->{nh};

    my $sth;
    my $results = $self->{results};
    $self->{rows}   = scalar( $results ? keys %{$results} : 0 );

# if we have asked to have sorting by another column (non score), create the part of the query that handles taht
    $self->debug( "Setting up sorting for GT::SQL::Search::STH" ) if ($self->{_debug});
    my $sb;

# clean up the sort by columns.
    unless ($self->{'score_sort'}) {
        $sb = GT::SQL::Search::Base::Search->clean_sb($self->{sb}, $self->{so});
    }

# setup the max hits and the offsets
    $self->{index}  = $self->{nh} * $self->{mh} || 0;
    $self->{max_index} = $self->{index} + $self->{mh} - 1; # index + mh is the first record which should not be returned.

    if ( $self->{max_index} > $self->{rows} ) {
        $self->{max_index}  = $self->{rows};
        $self->{rows}       = $self->{rows} - $self->{index};
        $self->{rows} < 0 ? $self->{rows} = 0 : 0;
    }

    else {
        $self->{rows}       = $self->{mh};
    }

# if we are sorting by another column, handle that
    if ( $sb and (keys %{$self->{results}})) {
        my ( $table, $pk ) = $self->_table_info();
        my ( $query, $where, $st, $limit );

        $where      = qq!$pk in(! . join( ",", keys %{$self->{results}}) . ')';
        $self->{mh} and $limit = qq!LIMIT $self->{index}, $self->{rows}!;
        $query      = qq!
            SELECT $pk
            FROM   $table
            WHERE  $where
            $sb
            $limit
        !;
        $self->debug( "Row fetch query: $query" ) if ($self->{_debug});
        $sth        = $self->{table}->{driver}->prepare( $query );
        $sth->execute();

# fix the counts
        $self->{index}    = 0;
        $self->{max_hits} = $self->{rows};

# now return them
        my $order         = $sth->fetchall_arrayref();
        $sth->finish();

        $self->{'order'}  = [ map { $_->[0] } @{$order} ];
    }
    else {
        $self->{'order'}  = [ sort { 
                                        ( $results->{$b} || return 0 ) <=> ( $results->{$a} || 0 )
                                  } keys %{$results} ];
        $self->debug_dumper( "Results will be presented in the following order: ", $self->{'order'} ) if ($self->{_debug});
    }

}

sub cache_results {
#--------------------------------------------------------------------------------
    my $self    = shift;

    my $results = $self->{'results'};
    my ($sth, @records, $i, %horder, @order, $in_list);
    my $table   = $self->{table};
    my $tname   = $table->name();
    my ($pk)    = $self->{table}->pk;

    use GT::SQL::Condition;

# we know what we're doing here so shut off warns (complains about uninit'd values in range
# if thee aren't enough elements in the order array)
    my $w     = $^W; $^W = 0;
    @order    = grep $_, @{$self->{'order'} || []}[$self->{index}..$self->{max_index}] or return [];
    $^W       = $w;

    $i        = 0; %horder  = ( map { ( $_ => $i++) } @order );
    $in_list  = join ( ",", @order );
    my $query = qq|
        SELECT * 
        FROM
            $tname
        WHERE
            $pk IN($in_list)
    |;

# the following is left commented out as...
# if $tbl->select is used $table->hits() will not
# return an accurate count of the number of all the hits. instead, will return
# a value up to mh. $tbl->hits() is important because the value is used
# in toolbar calculations
#
#    $sth     = $table->select( GT::SQL::Condition->new( $pk, 'IN', \"($in_list)" ) );
    $sth = $table->do_query( $query );

    while ( my $href = $sth->fetchrow_hashref() ) { 
        $records[$horder{$href->{$pk}}] = \%$href
    }

    return \@records;

}

sub fetchrow_array {
#--------------------------------------------------------------------------------
    return @{ $_[0]->fetchrow_arrayref() || [] };
}

sub fetchrow_arrayref {
#--------------------------------------------------------------------------------
    my $self    = shift;
    my $records = $self->{cache} ||= $self->cache_results;
    my $href    = shift @$records or return;
    return $self->_hash_to_array($href);
}

sub fetchrow_hashref {
#--------------------------------------------------------------------------------
    my $self    = shift;

    my $results = $self->{'results'};
    my $records = $self->{cache} ||= $self->cache_results;
    my $table   = $self->{table};
    my ($pk)    = $self->{table}->pk;

    my $href    = shift @$records or return;

    $href->{$self->{'score_col'}} = ( $self->{score} = $results->{$href->{$pk}} );

    return $href;

}

sub fetchall_hashref {
#--------------------------------------------------------------------------------
    my $self = shift;
    my @results;
    while (my $res = $self->fetchrow_hashref) {
        push @results, $res;
    }
    return \@results;
}

sub fetchall_list {
#--------------------------------------------------------------------------------
    return { map { @$_ } @{shift->fetchall_arrayref} }
}

sub fetchall_arrayref {
#--------------------------------------------------------------------------------
    my $self    = shift;

    $self->{order} or return [];
    my $results = $self->{results};
    my ($pk)    = $self->{table}->pk;
    my $scol    = $self->{score_col};


    if (!$self->{allref_cache}) {
        $self->{allref_cache} ||= $self->cache_results;

        for my $i ( 0 .. $#{$self->{allref_cache}} ) {
            my $element = $self->{allref_cache}->[$i];
            if ( $_[0] eq 'HASH' ) {
                    $element->{$scol} = $results->{$element->{$pk}};
            }
            else {
                    $element->{$scol} = $self->_hash_to_array( $element->{$scol} );
            }
        };
    }

    my $records = $self->{allref_cache};

    return $records;
}

sub score {
#--------------------------------------------------------------------------------
    my $self    = shift;
    return $self->{score};
}

sub _hash_to_array {
#--------------------------------------------------------------------------------
    my $self    = shift;
    my $href    = shift or return;

    my $results = $self->{'results'};
    my $table   = $self->{table};
    my $cols    = $table->cols();
    my $ordercols = ( $self->{ordercols} ||= [ sort { $cols->{$a}->{pos} <=> $cols->{$b}->{pos} } keys %$cols ] );
    my ($pk)    = $self->{table}->pk;
    my $aref    = [ map { $href->{$_} } @$ordercols, ( $self->{score} = $results->{$href->{$pk}} ) ];

    return $aref;
}

sub rows {
#--------------------------------------------------------------------------------
    my $self    = shift;
    return $self->{rows};
}

sub _table_info {
#--------------------------------------------------------------------------------
    my $self    = shift;
    my $table   = $self->{table}->name() or return $self->error('NOSCHEMA', 'FATAL');
    my ($pk)    = $self->{table}->pk;
    return ( $table, $pk );
}

sub DESTROY {
#--------------------------------------------------------------------------------
    my $self    = shift;
    $self->{'sth'} and $self->{'sth'}->finish();
}

sub debug_dumper {
#--------------------------------------------------------------------------------
# calls debug but also dumps all the messages
    my $self    = shift;
    my $message = shift;
    my $level   = ref $_[0] ? 1 : shift;

    if ( $self->{_debug} >= $level ) {
        require GT::Dumper;
        $self->debug( $message . join( "", map { GT::Dumper::Dumper($_) } @_ )) if ($self->{_debug});
    }
}

1;