#!/usr/bin/perl -w
###############################################################################
# $Id$
###############################################################################
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
###############################################################################

=head1 NAME

VCL::reclaim - Perl module for the VCL reclaim state

=head1 SYNOPSIS

 use VCL::reclaim;
 use VCL::utils;

 # Set variables containing the IDs of the request and reservation
 my $request_id = 5;
 my $reservation_id = 6;

 # Call the VCL::utils::get_request_info subroutine to populate a hash
 my $request_info = get_request_info($request_id);

 # Set the reservation ID in the hash
 $request_info->{RESERVATIONID} = $reservation_id;

 # Create a new VCL::reclaim object based on the request information
 my $reclaim = VCL::reclaim->new($request_info);

=head1 DESCRIPTION

 This module supports the VCL "reclaim" state.

=cut

###############################################################################
package VCL::reclaim;

# Specify the lib path using FindBin
use FindBin;
use lib "$FindBin::Bin/..";

# Configure inheritance
use base qw(VCL::Module::State);

# Specify the version of this module
our $VERSION = '2.5.1';

# Specify the version of Perl to use
use 5.008000;

use strict;
use warnings;
use diagnostics;

use VCL::utils;

###############################################################################

=head1 OBJECT METHODS

=cut

#//////////////////////////////////////////////////////////////////////////////

=head2 process

 Parameters  : Reference to state object
 Returns     : Nothing, process always exits
 Description : Processes a reservation in the timeout and deleted states.

=cut

sub process {
	my $self = shift;
	
	# Get required data
	my $request_data                        = $self->data->get_request_data();
	my $reservation_id                      = $self->data->get_reservation_id();
	my $request_state_name                  = $self->data->get_request_state_name();
	my $request_laststate_name              = $self->data->get_request_laststate_name();
	my $computer_id                         = $self->data->get_computer_id();
	my $computer_type                       = $self->data->get_computer_type();
	my $computer_shortname                  = $self->data->get_computer_short_name();
	my $computer_state_name                 = $self->data->get_computer_state_name();
	my $computer_imagerevision_id           = $self->data->get_computer_imagerevision_id();
	my $server_request_id                   = $self->data->get_server_request_id();
	my $public_ip_configuration             = $self->data->get_management_node_public_ip_configuration() || return;
	my @reservation_ids                     = $self->data->get_reservation_ids();

	# Remove related fixedIPsr variable, if it exists
	if ($server_request_id) {
		my $variable_name = "fixedIPsr" . $server_request_id;
		if (is_variable_set($variable_name)) {
			#Delete from variable table.
			my $delete_sql_statement = "DELETE variable FROM variable WHERE name = '$variable_name' ";
			if (database_execute($delete_sql_statement)) {
			notify($ERRORS{'DEBUG'}, 0, "Deleted server reservation entry for $variable_name from variable table");
			}   
		}   
		
		if ($public_ip_configuration =~ /static/i) {
			my $original_IPvalue = "originalIPaddr_" . $server_request_id;
			if (is_variable_set($original_IPvalue)) {
				my $original_Public_IP = get_variable($original_IPvalue);
				if (update_computer_public_ip_address($computer_id, $original_Public_IP)) {
					notify($ERRORS{'DEBUG'}, 0, "restored original IP address: $original_Public_IP for $computer_state_name ");
				}
				my $delete_sql_statement = "DELETE variable FROM variable WHERE name = '$original_IPvalue' ";
				if (database_execute($delete_sql_statement)) {
					notify($ERRORS{'DEBUG'}, 0, "Deleted server reservation entry for $original_IPvalue from variable table");
				}   
			}
		}
	}
	
	# Insert into computerloadlog if request state = timeout
	if ($request_state_name =~ /timeout|deleted/) {
		insertloadlog($reservation_id, $computer_id, $request_state_name, "reclaim: starting $request_state_name process");
	}
	
	notify($ERRORS{'DEBUG'}, 0, "beginning to reclaim $computer_shortname:\nrequest state: $request_state_name\nrequest laststate: $request_laststate_name\ncomputer state: $computer_state_name\ncomputer type: $computer_type");
	
	# Don't attempt to do anything to machines that are currently reloading
	if ($computer_state_name =~ /maintenance|reloading/) {
		notify($ERRORS{'OK'}, 0, "computer in $computer_state_name state, nothing needs to be done to the computer");
	}
	# If request laststate = new, nothing needs to be done
	elsif ($request_laststate_name =~ /new/) {
		notify($ERRORS{'OK'}, 0, "request laststate is $request_laststate_name, nothing needs to be done to the computer");
	}
	# Lab computers only need to be sanitized (have sshd disabled)
	elsif ($computer_type =~ /lab/) {
		notify($ERRORS{'OK'}, 0, "computer type is $computer_type, computer will be sanitized");
		$self->call_os_sanitize();
	}
	# If request laststate = reserved, user did not log in
	# Make sure image loaded on computer (currentimage.txt) matches what's set in computer.currentimageid
	elsif ($request_laststate_name =~ /reserved/) {
		notify($ERRORS{'DEBUG'}, 0, "request laststate is $request_laststate_name, checking if computer table current image matches image currently loaded on $computer_shortname");
		
		## If server reservations and in reserved - reload
		#if ($server_request_id) {
		#	notify($ERRORS{'DEBUG'}, 0, "Detected server reservations, computer will be reloaded");
		#	$self->insert_reload_and_exit();
		#}
		
		# Check if tainted tag was set in currently loaded image
		if ($self->os->get_tainted_status()) {
			notify($ERRORS{'DEBUG'}, 0, "image currently loaded on $computer_shortname was tainted, computer will be reloaded");
			$self->insert_reload_and_exit();
		}
		
		# Make sure computer current imagerevision ID was retrieved from the database
		if (!$computer_imagerevision_id) {
			notify($ERRORS{'WARNING'}, 0, "failed to retrieve computer current imagerevision ID from the database, computer will be reloaded");
			$self->insert_reload_and_exit();
		}
		
		# Reload the computer if unable to retrieve the current imagerevision ID from the OS
		my $os_current_imagerevision_id = $self->os->get_current_imagerevision_id();
		if (!$os_current_imagerevision_id) {
			notify($ERRORS{'WARNING'}, 0, "failed to retrieve imagerevision ID currently loaded on $computer_shortname, computer will be reloaded");
			$self->insert_reload_and_exit();
		}
		
		# Compare the database current imagerevision ID value with what's on the computer
		if ($computer_imagerevision_id eq $os_current_imagerevision_id) {
			notify($ERRORS{'DEBUG'}, 0, "computer table current imagerevision ID ($computer_imagerevision_id) matches imagerevision ID on computer ($os_current_imagerevision_id), computer will be sanitized");
			$self->call_os_sanitize();
		}
		else {
			notify($ERRORS{'DEBUG'}, 0, "computer table current imagerevision ID ($computer_imagerevision_id) does NOT match imagerevision ID on computer ($os_current_imagerevision_id), computer will be reloaded");
			$self->insert_reload_and_exit();
		}
	}
	# Request laststate is not reserved, user logged in
	else {
		notify($ERRORS{'OK'}, 0, "request laststate is $request_laststate_name, computer will be reloaded");
		$self->insert_reload_and_exit();
	}


	# Update the request state to complete and exit
	# Set the computer state to available if it isn't in the maintenance or reloading state
	if ($computer_state_name =~ /maintenance|reloading/) {
		notify($ERRORS{'OK'}, 0, "$computer_shortname in $computer_state_name state, skipping state update to available");
		$self->state_exit('complete');
	}
	else {
		$self->state_exit('complete', 'available');
	}
} ## end sub process

#//////////////////////////////////////////////////////////////////////////////

=head2 insert_reload_and_exit

 Parameters  : Reference to state object
 Returns     : Nothing, process always exits
 Description : -Retrieves the next image to be loaded on the computer based on
                a predictive loading algorithm
               -Inserts a new reload request
               -Sets the state of the request being processed to complete
               -Sets the state of the computer to reload

=cut

sub insert_reload_and_exit {
	my $self = shift;
	my $request_data               = $self->data->get_request_data;
	my $computer_id                = $self->data->get_computer_id();
	my $computer_shortname         = $self->data->get_computer_short_name();
	
	$self->os->post_reservation();
	
	# Retrieve next image
	my ($action, $next_image_name, $next_image_id, $next_imagerevision_id) = $self->data->get_next_image_data_structure();

	if ($action =~ /unload/i) {
		if ($self->provisioner->can("unload")) {
			if ($self->provisioner->unload()) {
				if (update_computer_imagename($computer_id, 'noimage')) {
					notify($ERRORS{'DEBUG'}, 0, "set computer $computer_shortname current image to 'noimage'");
				}
				$self->state_exit('complete', 'available');
			}
		}
	}
	else {
	#elsif ($action =~ /reload/i) {
		if (!$next_image_name || !$next_image_id || !$next_imagerevision_id) {
			notify($ERRORS{'WARNING'}, 0, "predictor module did not return required information, calling get_next_image_default from utils");
			($next_image_name, $next_image_id, $next_imagerevision_id) = get_next_image_default($computer_id);
		}
		
		# Update the DataStructure object with the next image values
		# These will be used by insert_reload_request()
		$self->data->set_image_name($next_image_name);
		$self->data->set_image_id($next_image_id);
		$self->data->set_imagerevision_id($next_imagerevision_id);

		notify($ERRORS{'OK'}, 0, "next image: $next_image_name, image id=$next_image_id, imagerevision id=$next_imagerevision_id");
	
		# Insert reload request data into the database
		if (insert_reload_request($request_data)) {
			notify($ERRORS{'OK'}, 0, "inserted reload request into database for computer id=$computer_id, image=$next_image_name");

			# Switch the request state to complete, the computer state to reload
			$self->state_exit('complete', 'reload');
		}
		else {
			notify($ERRORS{'CRITICAL'}, 0, "failed to insert reload request into database for computer id=$computer_id image=$next_image_name");

			# Switch the request and computer states to failed
			$self->state_exit('failed', 'failed');
		}
	}

	notify($ERRORS{'DEBUG'}, 0, "exiting");
	exit;
}

#//////////////////////////////////////////////////////////////////////////////

=head2 call_os_sanitize

 Parameters  : Reference to state object
 Returns     : If successful: true
               If failed: exits
 Description : Calls the OS module's sanitize subroutine. If sanitize() fails,
               a reload request will be inserted into the database and this
               process will exit.

=cut

sub call_os_sanitize {
	my $self = shift;
	
	# Make sure sanitize() has been implemented by the OS module
	if (!$self->os->can("sanitize")) {
		notify($ERRORS{'WARNING'}, 0, "sanitize subroutine has not been implemented by the " . ref($self->os) . " OS module, computer will be reloaded");
		$self->insert_reload_and_exit();
	}
	
	my $computer_shortname = $self->data->get_computer_short_name();
	
	# Delete the reservation info JSON file
	my $enable_experimental_features = get_variable('enable_experimental_features', 0);
	if ($enable_experimental_features && !$self->os->delete_reservation_info_json_file()) {
		notify($ERRORS{'WARNING'}, 0, "failed to delete reservation info JSON file on $computer_shortname, computer will be reloaded");
		$self->insert_reload_and_exit();
	}
	
	# Attempt to call OS module's sanitize() subroutine
	# This subroutine should perform all the tasks necessary to sanitize the OS if it was reserved and not logged in to
	notify($ERRORS{'DEBUG'}, 0, "calling " . ref($self->os) . "::sanitize() subroutine");
	if ($self->os->sanitize()) {
		notify($ERRORS{'OK'}, 0, "$computer_shortname has been sanitized");
	}
	else {
		# OS module's sanitize() subroutine returned false, meaning reload is necessary
		notify($ERRORS{'WARNING'}, 0, "failed to sanitize $computer_shortname, computer will be reloaded");
		$self->insert_reload_and_exit();
	}
	
	return 1;
}

#//////////////////////////////////////////////////////////////////////////////

1;
__END__

=head1 SEE ALSO

L<http://cwiki.apache.org/VCL/>

=cut