package Simple::Abstraction;

use Carp;
use DBI;
use strict;

require Exporter;

our @ISA = qw(Exporter);

our %EXPORT_TAGS = ( 'all' => [ qw() ] );
our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );
our @EXPORT = qw();

our $VERSION = '0.33';

sub commit {
    my ($parent, $args) = @_;
    my ($self) = {};
    bless ($self);
    return undef unless (defined($parent->{dbh}));
    print STDERR "Simple::Abstraction->commit - Not implemented at thi
+s time\n" if ($parent->{debug});
    return;
};

sub connect {
    my ($param) = shift;
    my ($class) = ref($param) || $param;
    my ($parent) = {};
    bless ($parent, $class);
    my (%args) = @_;
    $parent->{debug} = ($args{'debug'} =~ /^\d+$/) ? $args{'debug'} : 
+0;
    $parent->{driver} = (length($args{'driver'})) ? $args{'driver'} : 
+"Pg";
    $parent->{username} = (length($args{'username'})) ? $args{'usernam
+e'} : undef;
    $parent->{password} = (length($args{'password'})) ? $args{'passwor
+d'} : undef;
    $parent->{database} = (length($args{'database'})) ? $args{'databas
+e'} : "test";
    $parent->{hostname} = (length($args{'hostname'})) ? $args{'hostnam
+e'} : "localhost";
    $parent->{dsn} = "DBI:" . $parent->{driver} . ":dbname=" . $parent
+->{database} . ";host=" . $parent->{hostname};

    print STDERR "Simple::Abstraction->connect - Creating connection t
+o DSN '", $parent->{dsn}, "'\n" if ($parent->{debug});

    unless ($parent->{dbh} = DBI->connect($parent->{dsn}, $parent->{us
+ername}, $parent->{password})) {
        croak "Cannot connect to '", $parent->{dsn}, "' - ", $DBI::err
+str, "\n";
    };
    return ($parent);
};

sub disconnect {
    my ($parent, $args) = @_;
    unless ($parent->{dbh}->disconnect) {
        croak "Cannot disconnect from '", $parent->{dsn}, "' - ", $DBI
+::errstr, "\n";
    };
    undef $parent;
    return 1;
};

sub new {
    my ($parent, $type, $args) = @_;
    my ($self) = {};
    bless ($self);
    return undef unless (defined($parent->{dbh}));

    $self->{type} = $type;
    $self->{parent} = \$parent;

    print STDERR "Simple::Abstraction->new - Creating new object of ty
+pe '", $self->{type}, "'\n" if (${$self->{parent}}->{debug});

    if (ref($args) eq 'HASH') {
        foreach my $param (keys(%{$args})) {
            $$args{$param} =~ s/\"/\\\"/g;
            eval qq/
                \$self->{data}->{$param} = "$$args{$param}";
            /;
            print STDERR "Simple::Abstraction->new - Setting parameter
+ '", $param, "' for object of type '", $self->{type}, "'\n" if (${$se
+lf->{parent}}->{debug});
        };
    };

    return ($self);
};

sub param {
    my ($self) = shift;
    my ($args) = @_;
    return undef unless (defined($self->{type}));

    if (ref($args) eq 'HASH') {
        foreach my $param (keys(%{$args})) {
            $$args{$param} =~ s/\"/\\\"/g;
            eval qq/
                \$self->{data}->{$param} = "$$args{$param}";
            /;
            print STDERR "Simple::Abstraction->param - Setting paramet
+er '", $param, "' for object of type '", $self->{type}, "'\n" if (${$
+self->{parent}}->{debug});
        };
    } elsif (defined($args)) {
        my ($param) = $args;
        if (defined($self->{data}->{$args})) {
            print STDERR "Simple::Abstraction->param - Returning param
+eter '", $args, "' for object of type '", $self->{type}, "'\n" if (${
+$self->{parent}}->{debug});
            return ($self->{data}->{$args});
        };
    } else {
        return (keys (%{$self->{data}}));
    };

    return;
};

sub select_array {
    my ($parent, $type, $args, $order) = @_;
    my ($self) = {};
    bless ($self);
    return undef unless (defined($parent->{dbh}));
    $self->{type} = $type;

    my (@results);

    print STDERR "Simple::Abstraction->select_array - Creating new arr
+ay for select results from table '", $self->{type}, "'\n" if ($parent
+->{debug});

    my ($sth) = $parent->{dbh}->prepare("select * from $self->{type}")
+;
    $sth->execute;

    my (@fields, @search);
    for (my $index = 0; $index < $sth->{NUM_OF_FIELDS}; $index++) {
        if (defined($$args{$sth->{NAME}->[$index]})) {
            push (@search, $sth->{NAME}->[$index]." ~~ '".$$args{$sth-
+>{NAME}->[$index]}."'");
        };
        push (@fields, $sth->{NAME}->[$index]);
    };
    my ($sth) = $parent->{dbh}->prepare("select * from $self->{type}" 
+.
        (($#search >= 0) ? " where ".join(" and ", @search) : undef) .
+ 
        ((ref($order) eq 'ARRAY') ? " order by ".join(", ", @{$order})
+ : undef)
    );
    $sth->execute;
    while (my (@row) = $sth->fetchrow_array) {
        my (%row);
        foreach my $field (@fields) {
            $row{$field} = shift(@row);
        };
        push (@results, $parent->new($self->{type}, \%row));
    };

    return (@results);
};


sub select_hash {
    my ($parent, $type, $args) = @_;
    my ($self) = {};
    bless ($self);
    return undef unless (defined($parent->{dbh}));
    $self->{type} = $type;

    my (%results);

    print STDERR "Simple::Abstraction->select_hash - Creating new hash
+ for select results from table '", $self->{type}, "'\n" if ($parent->
+{debug});

    my ($sth) = $parent->{dbh}->prepare("select * from $self->{type}")
+;
    $sth->execute;

    my (@fields, @search);
    for (my $index = 0; $index < $sth->{NUM_OF_FIELDS}; $index++) {
        if (defined($$args{$sth->{NAME}->[$index]})) {
            push (@search, $sth->{NAME}->[$index]." ~~ '".$$args{$sth-
+>{NAME}->[$index]}."'");
        };
        push (@fields, $sth->{NAME}->[$index]);
    };
    my ($sth) = $parent->{dbh}->prepare("select * from $self->{type}".
+(($#search >= 0) ? " where ".join(" and ", @search) : undef));
    $sth->execute;
    while (my (@row) = $sth->fetchrow_array) {
        my (%row);
        foreach my $field (@fields) {
            $row{$field} = shift(@row);
        };
        my ($result) = $parent->new($self->{type}, \%row);
        $results{$result->param($fields[0])} = $result;
    };

    return (%results);
};

1;

__END__