package Maypole::View::Base;
use File::Spec;
use UNIVERSAL::moniker;
use strict;
use Maypole::Constants;
use Carp;
sub new { bless {}, shift } # By default, do nothing.
sub paths {
my ( $self, $r ) = @_;
my $root = $r->config->template_root || $r->get_template_root;
if(ref($root) ne 'ARRAY') {
$root = [ $root ];
}
my @output = ();
my $i = 0;
foreach my $path (@$root) {
push(@output,
(
$r->model_class
&& File::Spec->catdir( $path, $r->model_class->table )
)
);
push(@output, File::Spec->catdir( $path, "custom" )) unless ($i);
push(@output, $path);
push(@output, File::Spec->catdir( $path, "factory" )) unless ($i);
$i = 1;
}
return grep( $_, @output);
}
sub vars {
my ( $self, $r ) = @_;
my $class = $r->model_class;
my $base = $r->config->uri_base;
$base =~ s/\/+$//;
my %args = (
request => $r,
objects => $r->objects,
base => $base,
config => $r->config,
);
$args{object} = $r->object if ($r->can('object'));
if ($class) {
my $classmeta = $r->template_args->{classmetadata} ||= {};
$classmeta->{name} ||= $class;
$classmeta->{table} ||= $class->table;
$classmeta->{columns} ||= [ $class->display_columns ] if ($class->can('display_columns'));
$classmeta->{list_columns} ||= [ $class->list_columns ] if ($class->can('list_columns'));
$classmeta->{colnames} ||= { $class->column_names } if ($class->can('column_names'));
$classmeta->{related_accessors} ||= [ $class->related($r) ];
$classmeta->{moniker} ||= $class->moniker;
$classmeta->{plural} ||= $class->plural_moniker;
$classmeta->{cgi} ||= { $class->to_cgi } if ($r->build_form_elements && $class->can('to_cgi'));
$classmeta->{stringify_column} ||= $class->stringify_column if ($class->can('stringify_column'));
# User-friendliness facility for custom template writers.
if ( @{ $r->objects || [] } > 1 ) {
$args{ $r->model_class->plural_moniker } = $r->objects;
}
else {
( $args{ $r->model_class->moniker } ) = @{ $r->objects || [] };
}
}
# Overrides
%args = ( %args, %{ $r->template_args || {} } );
%args;
}
sub process {
my ( $self, $r ) = @_;
my $status = $self->template($r);
return $self->error($r) if $status != OK;
return OK;
}
sub error {
my ( $self, $r, $desc ) = @_;
$desc = $desc ? "$desc: " : "";
if ( $r->{error} =~ /not found$/ ) {
warn "template not found error : ", $r->{error};
# This is a rough test to see whether or not we're a template or
# a static page
return -1 unless @{ $r->{objects} || [] };
my $template_error = $r->{error};
$r->{error} = <<EOF;
<h1> Template not found </h1>
A template was not found while processing the following request:
<strong>@{[$r->{action}]}</strong> on table
<strong>@{[ $r->{table} ]}</strong> with objects:
<pre>
@{[join "\n", @{$r->{objects}}]}
</pre>
The main template is <strong>@{[$r->{template}]}</strong>.
The template subsystem's error message was
<pre>
$template_error
</pre>
We looked in paths:
<pre>
@{[ join "\n", $self->paths($r) ]}
</pre>
EOF
$r->{content_type} = "text/html";
$r->{output} = $r->{error};
return OK;
}
return ERROR;
}
sub template { die shift() . " didn't define a decent template method!" }
1;
=head1 NAME
Maypole::View::Base - Base class for view classes
=head1 DESCRIPTION
This is the base class for Maypole view classes. This is an abstract class
that defines the interface, and can't be used directly.
=head2 process
This is the entry point for the view. It templates the request and returns a
C<Maypole::Constant> indicate success or failure for the view phase.
Anyone subclassing this for a different rendering mechanism needs to provide
the following methods:
=head2 template
In this method you do the actual processing of your template. it should use
L<paths> to search for components, and provide the templates with easy access
to the contents of L<vars>. It should put the result in C<$r-E<gt>output> and
return C<OK> if processing was sucessfull, or populate C<$r-E<gt>error> and
return C<ERROR> if it fails.
=head1 Other overrides
Additionally, individual derived model classes may want to override the
=head2 new
The default constructor does nothing. You can override this to perform actions
during view initialization.
=head2 paths
Returns search paths for templates. the default method returns folders for the
model class's C<moniker>, factory, custom under the configured template root.
=head2 vars
returns a hash of data the template should have access to. The default one
populates classmetadata if there is a table class, as well as setting the data
objects by name if there is one or more objects available.
=head2 error
=cut