#!/usr/bin/perl -w
# Copyright (C) 2019 all contributors <meta@public-inbox.org>
# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
#
# Used for purging messages entirely from a public-inbox.  Currently
# supports v2 inboxes only, for now.
use strict;
use warnings;
use Getopt::Long qw(:config gnu_getopt no_ignore_case auto_abbrev);
use PublicInbox::Admin qw(resolve_repo_dir);
PublicInbox::Admin::check_require('-index');
require PublicInbox::Filter::Base;
require PublicInbox::Config;
require PublicInbox::MIME;
require PublicInbox::V2Writable;

{ no warnings 'once'; *REJECT = *PublicInbox::Filter::Base::REJECT }

my $usage = "$0 [--all] [INBOX_DIRS] </path/to/message";
my $config = eval { PublicInbox::Config->new };
my $cfgfile = PublicInbox::Config::default_file();
my ($all, $force);
my $verbose = 1;
my %opts = (
	'all' => \$all,
	'force|f' => \$force,
	'verbose|v!' => \$verbose,
);
GetOptions(%opts) or die "bad command-line args\n", $usage, "\n";

# TODO: clean this up and share code with -index via ::Admin
my %dir2ibx; # ( path => Inbox object )
my @inboxes;
$config and $config->each_inbox(sub {
	my ($ibx) = @_;
	push @inboxes, $ibx if $all && $ibx->{version} != 1;
	$dir2ibx{$ibx->{mainrepo}} = $ibx;
});

if ($all) {
	$config or die "--all specified, but $cfgfile not readable\n";
	@ARGV and die "--all specified, but directories specified\n";
} else {
	my @err;
	my @dirs = scalar(@ARGV) ? @ARGV : ('.');
	my $u = 0;

	foreach my $dir (@dirs) {
		my $v;
		my $dir = resolve_repo_dir($dir, \$v);
		if ($v == 1) {
			push @err, $dir;
			next;
		}
		my $ibx = $dir2ibx{$dir} ||= do {
			warn "$dir not configured in $cfgfile\n";
			$u++;
			my $name = "unconfigured-$u";
			PublicInbox::Inbox->new({
				version => 2,
				name => $name,
				-primary_address => "$name\@example.com",
				mainrepo => $dir,
			});
		};
		push @inboxes, $ibx;
	}

	if (@err) {
		die "v1 inboxes currently not supported by -purge\n\t",
		    join("\n\t", @err), "\n";
	}
}

foreach my $ibx (@inboxes) {
	my $lvl = $ibx->{indexlevel};
	if (defined $lvl) {
		PublicInbox::Admin::indexlevel_ok_or_die($lvl);
		next;
	}

	# Undefined indexlevel, so `full'...
	# Search::Xapian exists and the DB can be read, at least, fine
	$ibx->search and next;

	# it's possible for a Xapian directory to exist, but Search::Xapian
	# to go missing/broken.  Make sure it's purged in that case:
	$ibx->over or die "no over.sqlite3 in $ibx->{mainrepo}\n";

	# $ibx->{search} is populated by $ibx->over call
	my $xdir_ro = $ibx->{search}->xdir(1);
	my $npart = 0;
	foreach my $part (<$xdir_ro/*>) {
		if (-d $part && $part =~ m!/[0-9]+\z!) {
			my $bytes = 0;
			$bytes += -s $_ foreach glob("$part/*");
			$npart++ if $bytes;
		}
	}
	if ($npart) {
		PublicInbox::Admin::require_or_die('-search');
	} else {
		# somebody could "rm -r" all the Xapian directories;
		# let them purge the overview, at least
		$ibx->{indexlevel} ||= 'basic';
	}
}

my $data = do { local $/; scalar <STDIN> };
$data =~ s/\A[\r\n]*From [^\r\n]*\r?\n//s;
my $n_purged = 0;

foreach my $ibx (@inboxes) {
	my $mime = PublicInbox::MIME->new($data);
	my $v2w = PublicInbox::V2Writable->new($ibx, 0);

	my $commits = $v2w->purge($mime) || [];

	if (my $scrub = $ibx->filter($v2w)) {
		my $scrubbed = $scrub->scrub($mime, 1);

		if ($scrubbed && $scrubbed != REJECT()) {
			my $scrub_commits = $v2w->purge($scrubbed);
			push @$commits, @$scrub_commits if $scrub_commits;
		}
	}

	$v2w->done;

	if ($verbose) { # should we consider this machine-parseable?
		print "$ibx->{mainrepo}:";
		if (scalar @$commits) {
			print join("\n\t", '', @$commits), "\n";
		} else {
			print " NONE\n";
		}
	}
	$n_purged += scalar @$commits;
}

# behave like "rm -f"
exit(0) if ($force || $n_purged);

warn "Not found\n" if $verbose;
exit(1);