package App::DuckPAN::DDG;
our $AUTHORITY = 'cpan:DDG';
# ABSTRACT: DDG related functionality of duckpan
$App::DuckPAN::DDG::VERSION = '1009';
use Moo;
with 'App::DuckPAN::HasApp';

use Module::Pluggable::Object;
use Class::Load ':all';
use Data::Printer return_value => 'dump';
use List::Util qw (first);

# This function tells the user which modules / instant answers failed to load.
sub show_failed_modules {
	my ($self, $failed_to_load) = @_;

	if (%$failed_to_load) {
		$self->app->emit_notice("These instant answers were not loaded:");
		$self->app->emit_notice(p($failed_to_load, colored => $self->app->colors));
		$self->app->emit_notice(
			"To learn more about installing Perl dependencies, please read http://docs.duckduckhack.com/resources/other-dev-environments.html#dealing-with-installation-issues.",
			"Note: You can ignore these errors if you're not working on these instant answers."
		) if first { /dependencies/ } values %$failed_to_load;
	}
}

sub get_blocks_from_current_dir {
	my ($self, @args) = @_;

	$self->emit_and_exit(1, 'You need to have the DDG distribution installed', 'To get the installation command, please run: duckpan check')
		unless ($self->app->get_local_ddg_version);

	my $type   = $self->app->get_ia_type;
	my $finder = Module::Pluggable::Object->new(
		search_path => [$type->{dir}],
	);
	if (scalar @args == 0) {
		$self->app->emit_and_exit(1, "No Fathead ID passed as argument.", "Please specify a Fathead ID e.g. 'duckpan server mdn_css'") if $type->{name} eq "Fathead";
		my @plugins = $finder->plugins;
		push @args, sort { $a cmp $b } @plugins;
		@args = map {
			$_ =~ s!/!::!g;
			my @parts = split('::', $_);
			shift @parts;
			join('::', @parts);
		} @args;
	}
	else {
		my @fatheads = grep {
			$type->{name} eq "Fathead"
		} @args;
		$self->app->fathead->selected(@fatheads);

		my @clean_args = grep {
			$type->{name} eq "Spice" || $type->{name} eq "Goodie"
		} @args;

		@args = map {
			$self->app->get_ia_by_name($_)->{perl_module}
		} @clean_args;
	}
	require lib;
	lib->import('lib');
	$self->app->emit_info("Loading Instant Answers...");

	# This list contains all of the classes that loaded successfully.
	my @successfully_loaded;

	# This hash contains all of the modules that failed.
	# The key contains the module name and the value contains the dependency that wasn't met.
	my %failed_to_load;

	my (%blocks_plugins, @UC_TRIGGERS);
	# This loop goes through each Goodie / Spice, and it tries to load it.
	foreach my $class (@args) {
		# Let's try to load each Goodie / Spice module
		# and see if they load successfully.
		my ($load_success, $load_error_message) = try_load_class($class);

		# If they load successfully, $load_success would be a 1.
		# Otherwise, it would be a 0.
		if ($load_success) {
			# Since we only want the successful classes to trigger, we
			# collect all of the ones that triggered successfully in a temporary list.
			push @successfully_loaded, $class;

			# Display to the user when a class has been successfully loaded.
			$self->app->emit_debug(" - $class (" . $class->triggers_block_type . ")");

			unless ($blocks_plugins{$class->triggers_block_type}) {
				$blocks_plugins{$class->triggers_block_type} = [];
			}

			my $triggers_block_type = $class->triggers_block_type;
			push @{$blocks_plugins{$triggers_block_type}}, $class;

			# We could potentially do other IA-specific checks here
			# Check for useless uppercase Words triggers so we can warn
			if($triggers_block_type eq 'Words'){
				my $trigger_types = $class->get_triggers;

				UC_TRIGGER: for my $triggers (values %$trigger_types){
					for my $t (@$triggers){
						if($t =~ /\p{Uppercase}/){
							push @UC_TRIGGERS, $class;
							#warn "is $t uppercase?\n";
							# the first one found should be sufficient.
							last UC_TRIGGER;
						}
					}
				}
			}
		}
		else {
			# Get the module name that needs to be installed by the user.
			if ($load_error_message =~ /Can't locate ([^\.]+).pm in \@INC/) {
				$load_error_message = $1;
				$load_error_message =~ s/\//::/g;

				$failed_to_load{$class} = "Please install $load_error_message and any other required dependencies to use this instant answer.";
			}
			else {
				# We just set the value to whatever the error message was if it failed for some other reason.
				$failed_to_load{$class} = $load_error_message;
			}
		}
	}

	# Since @args can contain modules that we don't want to trigger (since they didn't load in the first place),
	# and @successfully_loaded does, we just use what's in @successfully_loaded.
	@args = @successfully_loaded;

	# Now let's tell the user why some of the modules failed.
	$self->show_failed_modules(\%failed_to_load);

	if(@UC_TRIGGERS){
		$self->app->emit_notice('Detected potential UPPERCASE triggers in the following instant answers. If yours is listed, check it out! Only lowercase will work.' . "\n"
			. p(@UC_TRIGGERS, colored => $self->app->colors));
	}

	my @blocks;
	for (keys %blocks_plugins) {
		my $block_class = 'DDG::Block::' . $_;
		load_class($block_class);
		push @blocks,
		  $block_class->new(
			plugins    => $blocks_plugins{$_},
			return_one => 0
		  );
	}
	load_class('DDG::Request');
	return \@blocks;
}

1;

__END__

=pod

=head1 NAME

App::DuckPAN::DDG - DDG related functionality of duckpan

=head1 VERSION

version 1009

=head1 AUTHOR

Torsten Raudssus <torsten@raudss.us> L<https://raudss.us/>

=head1 COPYRIGHT AND LICENSE

This software is Copyright (c) 2013 by DuckDuckGo, Inc. L<https://duckduckgo.com/>.

This is free software, licensed under:

  The Apache License, Version 2.0, January 2004

=cut
