package IMPL::SQL::Schema::Constraint::ForeignKey;
use strict;
use warnings;

use IMPL::lang qw(:declare is);

use parent qw(IMPL::SQL::Schema::Constraint);


BEGIN {
    public _direct property referencedPrimaryKey => PROP_GET;
    public _direct property onDelete => PROP_GET;
    public _direct property onUpdate => PROP_GET;
}

__PACKAGE__->PassThroughArgs;
__PACKAGE__->RegisterAlias('fk');

sub CTOR {
    my ($this,%args) = @_;    
    
    die new Exception("Referenced table must be an instance of a table object") if not is($args{'referencedTable'},'IMPL::SQL::Schema::Table');
    
    die new Exception("Referenced columns must be a not empty list of columns") if not UNIVERSAL::isa($args{'referencedColumns'},'ARRAY') or not scalar(@{$args{'referencedColumns'}});
    
    my @ReferencedColumns = map {IMPL::SQL::Schema::Constraint::ResolveColumn($args{'referencedTable'},$_)} @{$args{'referencedColumns'}};
    my $ForeingPK = $args{'referencedTable'}->primaryKey or die new Exception('The referenced table doesn\'t have a primary key');
    
    scalar (@ReferencedColumns) == $this->columns->Count or die new Exception('A foreing key columns doesn\'t match refenced columns');
    my @ColumnsCopy = @ReferencedColumns;
    
    die new Exception('A foreing key columns doesn\'t match refenced columns') if grep { not $_->type->SameValue((shift @ColumnsCopy)->type)} @{$this->columns};
    
    @ColumnsCopy = @ReferencedColumns;
    die new Exception('The foreign key must match to the primary key of the referenced table',$this->name) if grep { not $_->type->SameValue(shift(@ColumnsCopy)->type)} @{$ForeingPK->columns};
    
    $this->{$referencedPrimaryKey} = $ForeingPK;
    
    $ForeingPK->ConnectFK($this);
    
    $this->onUpdate($args{onUpdate}) if $args{onUpdate};
    $this->onDelete($args{onDelete}) if $args{onDelete};
}

sub Dispose {
    my ($this) = @_;

    $this->{$referencedPrimaryKey}->DisconnectFK($this) if not $this->{$referencedPrimaryKey}->isDisposed;
    delete $this->{$referencedPrimaryKey};
    
    $this->SUPER::Dispose;
}

sub SameValue {
    my ($this,$other) = @_;
    
    uc($this->onDelete || '') eq uc($other->onDelete || '')or return 0;
    uc($this->onUpdate || '') eq uc($other->onUpdate || '') or return 0;
    
    return $this->SUPER::SameValue($other);
}



1;