package PH;

# Set to an empty array to indicate that we're preparing a statement
my $inside_prepare = undef;

sub TIESCALAR {
    my ($class, $var) = @_;
    return bless \$var, $class;
}

# When we're preparing a statement, we'll return '?' for a tied value,
# and push a reference to the variable on the inside_prepare vector
# so the values and placeholders line up
sub FETCH {
    my $self = shift;
    return $$self unless defined $inside_prepare;
    push @$inside_prepare, $self;
    return "?";
}

sub STORE {
    my ($self,$new_val) = @_;
    $$self = $new_val;
}

# Fake DBI prep-like statement
sub prep {
    # Tell FETCH() that we're prepping a statement
    $inside_prepare = [];

    # call the sub to make perl do the string interpolation and
    # build the vector of variable references that align with
    # the placeholders
    my $t = shift;
    my $retval = [ $t->(), $inside_prepare ];

    # Turn off preparation mode
    $inside_prepare = undef;

    print "PREPARED: $retval->[0]\n";
    return $retval;
}

# Fake DBI execute-like statement
sub exec {
    my $x = shift;
    print "EXEC(", join(", ", map { $$_ } @{$x->[1]}), ")\n";
}

1;