<?php

/*
	This file is part of the ParTCP Server project
	Copyright (C) 2022 Martin Wandelt

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Affero General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Affero General Public License for more details.

	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <https://www.gnu.org/licenses/>
*/

class ParTCP_Events {
	
	public $fileSystem;
	public $dataDir;
	public $groupsClass;
	public $lastInvalidField;


	public function __construct( $fileSystem, $dataDir ){
		$this->fileSystem = $fileSystem;
		$this->dataDir = $dataDir;
	}


	public function get_dir( $id ){
		if ( is_object( $this->groupsClass ) && strpos( $id, '/' ) ){
			$groupDir = $this->groupsClass->get_dir( dirname( $id ) );
			if ( ! $groupDir ){
				return FALSE;
			}
			$id = basename( $id );
		}
		return ( isset( $groupDir ) ? "{$groupDir}/" : '' ) . "events/{$id}";
	}


	public function get_list( $groupId = FALSE, $status = NULL ){
		$dir = 'events';
		if ( is_object( $this->groupsClass ) && $groupId ){
			$dir = $this->groupsClass->get_dir( $groupId ) . "/{$dir}";
		}
		if ( ! $this->fileSystem->exists( $dir ) ){
			return array ();
		}
		$eventList = $this->fileSystem->get_listing( $dir );
		$events = array ();
		foreach ( $eventList as $eventId ){
			$eventId = ( $groupId ? "{$groupId}/" : '' ) . $eventId;
			if ( ! ( $data = $this->get_data( $eventId ) ) ){
				continue;
			}
			$this->update_calculated_fields( $data );
			if ( empty( $status ) || $status == 'all'
				|| in_array( $data['status'], (array) $status )
			){
				$events[] = $data;
			}
		}
		return $events;
	}


	public function get_data( $id ){
		$dir = $this->get_dir( $id );
		$msg = $this->fileSystem->get_recent_contents( $dir, '[0-9]*-{update,definition,declaration}*' );
		if ( empty( $msg ) ){
			return FALSE;
		}
		$receipt = yaml_parse( $msg );
		if ( empty( $receipt['Event-Data'] ) ){
			return FALSE;
		}
		$data = $receipt['Event-Data'];
		$data['lot_codes'] = $this->fileSystem->is_not_empty( "{$dir}/lots" );
		if ( ! array_key_exists( 'date_open', $data ) ){
			$data['date_open'] = $data['created_on'];
		}
		$this->update_calculated_fields( $data );
		return $data;
	}


	public function purge_data( $data ){
		$validKeys = [
			'id' => 0,
			'name' => 0,
			'date' => 0,
			'short_description' => 0,
			'description' => 0,
			'link_url' => 0,
			'client_data' => 0,
			'estimated_turnout' => 0,
			'voting_sort_key' => 0,
			'voting_sort_order' => 0,
			'issue_service' => 0,
			'naming_rules' => 0,
			'credential_rules' => 0,
			'lot_code_rules' => 0,
			'is_demo' => 0,
			'is_live' => 0,
			'is_local' => 0,
			'is_non_anonymous' => 0,
			'voting_sort_key' => 0,
			'voting_sort_order' => 0,
			'wlan_ssid' => 0,
			'date_open' => 0,
			'date_close' => 0,
			'date_finish' => 0,
			'badge_categories' => 0,
			'badge_expiration' => 0,
			'active_sessions' => 0,
			'mutex_event' => 0, // event_server, event_id, issue_server, ptcpid_regex, ptcpid_template
		];
		return array_intersect_key( $data, $validKeys );
	}


	public function validate_fields( $data ){
		if ( ! empty( $data['date'] ) ){
			$date = strtotime( $data['date'] );
			if ( ! $date || date( 'Ymd', $date ) < date('Ymd') ){
				$this->lastInvalidField = 'date';
				return FALSE;
			}
		}
		if ( ! empty( $data['estimated_turnout'] ) ){
			if ( ! is_int( $data['estimated_turnout'] )
				|| $data['estimated_turnout'] < 1
				|| $data['estimated_turnout'] > 1000000
			){
				$this->lastInvalidField = 'estimated_turnout';
				return FALSE;
			}
		}
		if ( ! empty( $data['date_open'] ) ){
			$dateOpen = strtotime( $data['date_open'] );
			if ( ! $dateOpen || $dateOpen < time() ){
				$this->lastInvalidField = 'date_open';
				return FALSE;
			}
		}
		if ( ! empty( $data['date_close'] ) ){
			$dateClose = strtotime( $data['date_close'] );
			if ( ! $dateClose || $dateClose < time()
				|| ( ! empty( $dateOpen ) && $dateClose <= $dateOpen )
			){
				$this->lastInvalidField = 'date_close';
				return FALSE;
			}
		}
		if ( ! empty( $data['date_finish'] ) ){
			$dateFinish = strtotime( $data['date_finish'] );
			if ( ! $dateFinish || $dateFinish < time()
				|| ( ! empty( $dateClose ) && $dateFinish <= $dateClose )
			){
				$this->lastInvalidField = 'date_finish';
				return FALSE;
			}
		}
		return TRUE;
	}


	public function set_status( &$data, $newStatus, $timestamp ){
		$allowedStatus = [
			'opened' => [ 'planned' ],
			'closed' => [ 'opened' ],
			'finished' => [ 'opened', 'closed' ],
		];
		$dateField = [
			'opened' => 'date_open',
			'closed' => 'date_close',
			'finished' => 'date_finish',
		];
		if ( ! in_array( $newStatus, array_keys( $allowedStatus ) ) ){
			return -1;
		}
		if ( ! in_array( $data['status'], $allowedStatus[ $newStatus ] ) ){
			return -2;
		}
		$data[ $dateField[ $newStatus ] ] = date( 'c', $timestamp );
		$data['status'] = $newStatus;
		return 1;
	}


	public function update_calculated_fields( &$data ){
		$data['naming_rules']['counter_width'] = strlen( $data['estimated_turnout'] );
		$r = $data['naming_rules'];
		$pattern = str_repeat( '#', strlen( $r['prefix'] ) + $r['counter_width'] + $r['crc_length'] );
		$pattern = chunk_split( $pattern, $r['group_length'] ?: 99, $r['group_separator'] );
		$data['naming_rules']['pattern'] = substr( $pattern, 0, -1 );
		$r = $data['credential_rules'];
		$pattern = str_repeat( '#', $r['final_length'] );
		$pattern = chunk_split( $pattern, $r['group_length'] ?: 99, $r['group_separator'] );
		$data['credential_rules']['pattern'] = substr( $pattern, 0, -1 );
		$r = $data['lot_code_rules'];
		$pattern = str_repeat( '#', $r['final_length'] );
		$pattern = chunk_split( $pattern, $r['group_length'] ?: 99, $r['group_separator'] );
		$data['lot_code_rules']['pattern'] = substr( $pattern, 0, -1 );
		$now = time();
		if ( ! empty( $data['date_finish'] )
			&& strtotime( $data['date_finish'] ) <= $now
		){
			$data['status'] = 'finished';
		}
		elseif ( ! empty( $data['date_close'] )
			&& strtotime( $data['date_close'] ) <= $now
		){
			$data['status'] = 'closed';
		}
		elseif ( ! empty( $data['date_open'] )
			&& strtotime( $data['date_open'] ) <= $now
		){
			$data['status'] = 'opened';
		}
		else {
			$data['status'] = 'planned';
		}
	}


	public function generate_code( $args = [] ){
		$charList = (string) ( $args['char_list'] ?? 'ABCDEFGHJKLMNPQRSTUVWXYZ123456789' );
		$finalLength = (int) ( $args['final_length'] ?? 16 );
		$groupLength = $args['group_length'] ?? 4;
		$groupSeparator = $args['group_separator'] ?? '-'; 
		$crcLength = $args['crc_length'] ?? 0;
		$netLength = $finalLength - $crcLength;
		$charListLength = strlen( $charList ) - 1;
		$code = '';
		for ( $x = 1; $x <= $netLength; $x++ ){
			$code .= $charList[ rand( 0, $charListLength ) ];
		}
		if ( $groupLength ){
			$code .= str_repeat( ' ', $crcLength );
			$code = substr( chunk_split( $code, $groupLength, $groupSeparator ), 0, -1 );
			$code = rtrim( $code, ' ' );
		}
		if ( $crcLength ){
			$code .= substr( crc32( $code ), - $crcLength );
		}
		elseif ( $groupLength ){
			$code = rtrim( $code, $groupSeparator );
		}
		return $code;
	}


	public function string_to_name( $str ){
		$str = strtolower( $str );
		$str = preg_replace( '/\s+/', '-', $str );
		$str = str_replace( ['ä','ö','ü','ß'], ['ae','oe','ue','ss'], $str );
		$str = html_entity_decode( $str, ENT_QUOTES, 'utf-8' );
		$str = htmlentities( $str, ENT_QUOTES, 'utf-8' );
		$str = preg_replace( '/(&)([a-z])([a-z]+;)/i', '$2', $str );
		$str = preg_replace( '/[^a-zA-Z0-9\-\._]/', '', $str );
		return $str;
	}


	public function get_statistics( $eventId, $ignoreCounters = FALSE ){
		global $Counter;
		$baseDir = $this->get_dir( $eventId );
		$lots = $deposits = $invalidations = $pickUps = $submissions = 0;
		if ( ! $this->fileSystem->exists( "{$baseDir}/lots" )
			|| ! $this->fileSystem->exists( "{$baseDir}/participants" )
		){
			return [
				'lots_created' => 0,
				'lots_invalidated' => 0,
				'lotcodes_deposited' => 0,
				'lots_redeemed' => 0,
				'keys_submitted' => 0
			];
		}
		if ( $ignoreCounters ){
			$lots = $this->fileSystem->count_items_in_recent('{$baseDir}/lots');
			if ( $lots ){
				$pickUps = $this->fileSystem->count_items_in_recent( '{$baseDir}/lots', 'pick-up-note', TRUE );
				$invalidations = $this->fileSystem->count_items_in_recent( '{$baseDir}/lots', 'lot-invalidation', TRUE );
				$submissions = $this->fileSystem->count_items_in_recent( '{$baseDir}/lots', '*-key-submission', TRUE );
			}
		}
		else {
			$Counter->set_base_dir( $baseDir );
			$lots = $Counter->get_value( 'lots' );
			$deposits = $Counter->get_value( 'deposits' );
			$invalidations = $Counter->get_value( 'invalidations' );
			$pickUps = $Counter->get_value( 'pick-ups' );
			$submissions = $Counter->get_value( 'key-submissions' );
		}
		return [
			'lots_created' => $lots,
			'lots_invalidated' => $invalidations,
			'lotcodes_deposited' => $deposits,
			'lots_redeemed' => $pickUps,
			'keys_submitted' => $submissions
		];
	}


	public function generate_secret( $eventId ){
		$eventDir = $this->get_dir( $eventId );
		$path = "{$this->dataDir}/{$eventDir}/secret";
		if ( ! file_exists( dirname( $path ) ) ){
			mkdir( dirname( $path ), 0700, TRUE );
		}
		file_put_contents( $path, random_bytes( 64 ) );
		chmod( $path, 0600 );
		return TRUE;
	}


	public function get_secret( $eventId ){
		$eventDir = $this->get_dir( $eventId );
		$path = "{$this->dataDir}/{$eventDir}/secret";
		if ( ! file_exists( $path ) ){
			return FALSE;
		}
		return file_get_contents( $path );
	}


	public function update_issue_service( $eventNew, $eventOld = NULL ){
		global $Partcp, $ServerData;

		$hostOld = $eventOld['issue_service']['host'] ?? '';
		$hostNew = $eventNew['issue_service']['host'] ?? '';

		if ( ! $hostOld && ! $hostNew ){
			return;
		}

		if ( $hostOld ){
			$host = $hostOld == 'localhost' ? $ServerData['name'] : $hostOld;
			$Partcp->set_remote_id ( $host );
			$data = [
				'voting_server' => in_array( $hostOld, [ $ServerData['name'], 'localhost' ] )
					? 'localhost' : $ServerData['name'],
				'event_id' => $eventOld['id']
			];
			$msg = [
				'Message-Type' => 'issue-service-update-request',
				'Issue-Service-Data' => $data
			];
			$Partcp->send_message( $msg );
		}

		if ( $hostNew && $hostNew != $hostOld ){
			$host = $hostNew == 'localhost' ? $ServerData['name'] : $hostNew;
			$Partcp->set_remote_id ( $host );
			$data = [
				'voting_server' => in_array( $hostNew, [ $ServerData['name'], 'localhost' ] )
					? 'localhost' : $ServerData['name'],
				'event_id' => $eventNew['id'],
				'id_provider' => $eventNew['issue_service']['id_provider'],
				'terms' => $eventNew['issue_service']['terms']
			];
			$msg = [
				'Message-Type' => 'issue-service-definition',
				'Issue-Service-Data' => $data
			];
			$Partcp->send_message( $msg );
		}
	}

}

// end of file models/events.class.php