#!/usr/bin/perl
#
# Accepts a HTTP PUT request to set the cluster membership of a host.
#

use strict;
use warnings;
use Anvil::Tools;
use Data::Dumper;
use JSON

$| = 1;

my $THIS_FILE         = ($0 =~ /^.*\/(.*)$/)[0];
my $running_directory = ($0 =~ /^(.*?)\/$THIS_FILE$/)[0];
if (($running_directory =~ /^\./) && ($ENV{PWD}))
{
	$running_directory =~ s/^\./$ENV{PWD}/;
}

my $anvil = Anvil::Tools->new();

sub alter_host_membership
{
	# Expects the first of positional parameters to be a hash.
	my $parameters   = shift;
	my $host_uuid    = $parameters->{host_uuid};
	my $join_cluster = $parameters->{join_cluster};

	$anvil->Log->variables({
		source => $THIS_FILE,
		line   => __LINE__,
		level  => 2,
		list   => {
			host_membership_status => Dumper($anvil->data->{hosts}{host_uuid}{$host_uuid})
		}
	});
}

# Re-adds a host to its anvil cluster.
#
# Note: not to be confused wtih adding a new host the an anvil.
#sub join_cluster
#{}

# Removes a host from its anvil cluster.
#
# Note: does not permanently remove the host; can be re-added.
#sub leave_cluster
#{}

$anvil->Get->switches;

# TODO: remove when done; temporarily set log level to 2
$anvil->Log->level({ set => 2 });

$anvil->Database->connect;
$anvil->Log->entry({source => $THIS_FILE, line => __LINE__, level => 2, secure => 0, key => "log_0132"});
if (not $anvil->data->{sys}{database}{connections})
{
	# No databases, exit.
	$anvil->Log->entry({source => $THIS_FILE, line => __LINE__, level => 0, 'print' => 1, priority => "err", key => "error_0003"});
	$anvil->nice_exit({exit_code => 1});
}

# Read in any CGI variables, if needed.
$anvil->Get->cgi();

$anvil->Database->get_hosts();
$anvil->Database->get_anvils();

print $anvil->Template->get({file => "shared.html", name => "json_headers", show_name => 0})."\n";

my $response_body = {};

my $request_body;

my $is_decode_json_success = eval {
	$request_body = decode_json($anvil->data->{cgi}{PUTDATA}{value});
};

if (not $is_decode_json_success)
{
	$anvil->Log->entry({
		source    => $THIS_FILE,
		line      => __LINE__,
		level     => 0,
		'print'   => 1,
		priority  => "err",
		key       => "error_0304",
		variables => { request_body_string => $anvil->data->{cgi}{PUTDATA}{value}, json_decode_error => $_ }
	});
	$anvil->nice_exit({ exit_code => 1 });
}

my $host_uuid = exists $request_body->{host_uuid} ? $request_body->{host_uuid} : "";
# Defaults to join; will check whether host is already part of its anvil cluster.
my $is_member = exists $request_body->{is_member} ? $request_body->{is_member} : 1;

if ($host_uuid)
{
	if (exists $anvil->data->{hosts}{host_uuid}{$host_uuid})
	{
		alter_host_membership({ host_uuid => $host_uuid, join_cluster => $is_member });
	}
	else
	{
		$anvil->Log->entry({
			source    => $THIS_FILE,
			line      => __LINE__,
			level     => 0,
			'print'   => 1,
			priority  => "err",
			key       => "error_0160",
			variables => { name => "host UUID", uuid => $host_uuid }
		});
		$anvil->nice_exit({ exit_code => 1 });
	}
}

print JSON->new->utf8->encode($response_body)."\n";