#! /usr/bin/env raku

use v6.d;

#| Start a slideshow of the given directories using feh.
sub MAIN(
	#| The directories to include for the slideshow.
	*@dirs,

	#| Show the command to be executed, and exit. Useful for debugging purposes.
	Bool:D :$dry-run = False,

	#| The timeout or delay between pictures. Defaults to 5.
	Int:D :$timeout = 5,
) {
	my $aliases-file = $*HOME.add('.local/etc/slideshow/aliases').IO;
	my $cmd = "feh -zsZ.D $timeout";
	my @cmd-args;
	my %aliases;

	# Use aliases if such a configuration is found.
	if ($aliases-file.f) {
		$aliases-file
			.lines
			.map({
				my ($key, $value) = $_.words;
				my $resolved-value = $value
					.subst('$HOME', $*HOME.absolute)
					;

				%aliases{$key}.append: $resolved-value;
			})
	}

	for @dirs {
		# Transform aliases as needed
		if (%aliases{$_}:exists) {
			@cmd-args.append(%aliases{$_});
			next;
		}

		@cmd-args.append: $_;
	}

	if ($dry-run) {
		say "$cmd {@cmd-args}";
		exit 0;
	}

	run « $cmd {@cmd-args} »;
}