<?php

/*
	This file is part of the ParTCP Server project
	Copyright (C) 2023 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_LC_Service_Messages {
	
	static function handle_lc_event_definition( $message, $receipt ){
		global $Events, $FileSystem, $Groups, $Shortcoder, $Timestamp;

		$eventData = $message->get('Event-Data');
		if ( empty( $eventData['name'] )
			|| empty( $eventData['estimated_turnout'] )
		){
			$receipt->set_rejection( 21, _('Incomplete event data') );
			return $receipt->dump( TRUE );
		}
		
		if ( empty( $eventData['date'] ) ){
			$eventData['date'] = date('Y-m-d');
			$date = time();
		}
		else {
			$date = is_int( $eventData['date'] ) ? $eventData['date'] : strtotime( $eventData['date'] );
			if ( ! $date || date( 'Ymd', $date ) < date('Ymd') ){
				$receipt->set_rejection( 22, _('Invalid event date') );
				return $receipt->dump( TRUE );
			}
			$eventData['date'] = date( 'Y-m-d', $date );
		}

		$estTurnout = (int) $eventData['estimated_turnout'];
		if ( $estTurnout < 1 || $estTurnout > 1000000 ){
			$receipt->set_rejection( 23, _('Invalid value for estimated turnout') );
			return $receipt->dump( TRUE );
		}

		$object = NULL;
		$groupId = $message->get('Group-Id');
		if ( $groupId && is_object( $Groups ) ){
			if ( ! $Groups->get_data( $groupId ) ){
				$receipt->set_rejection( 41, _('Group does not exist') );
				return $receipt->dump( TRUE );
			}
			$object = [
				'type' => 'group',
				'id' => $groupId,
				'dir' => $Groups->get_dir( $groupId )
			];
		}
		$sender = $message->get('From');
		if ( ! ptcp_is_authorized( $sender, 'event-definition', $object ) ){
			$receipt->set_rejection( 31, _('Sender is not authorized to define event here') );
			return $receipt->dump( TRUE );
		}
		$name = substr( $Events->string_to_name( $eventData['name'] ), 0, 32 );
		$id = $origId = ( $groupId ? $groupId . '/' : '' ) . date( 'Ymd', $date ) . "-{$name}";
		$dir = $Events->get_dir( $id );
		while ( $FileSystem->exists( $dir ) ){
			$count = $id == $origId ? 2 : (int) substr( $id, strrpos( $id, '-' ) + 1 ) + 1;
			$id = "{$origId}-{$count}";
			$dir = $Events->get_dir( $id );
		}
		$success = $FileSystem->make_dir( $dir );
		if ( ! $success ){
			$receipt->set_failure( _('Could not create event directory') . ': '
				. $FileSystem->lastError );
			return $receipt->dump( TRUE );
		}
		$Events->generate_secret( $id );

		$data = [
			'id' => $id,
			'created_on' => date( 'c', $Timestamp ),
			'created_by' => $sender,
			'modified_on' => null,
			'modified_by' => null,
			'naming_rules' => [
				'prefix' => 'p',
				'crc_length' => 1,
				'group_length' => 3,
				'group_separator' => '.'
			],
			'credential_rules' => [
				'char_list' => '1234567890',
				'final_length' => 9,
				'crc_length' => 1,
				'group_length' => 3,
				'group_separator' => '.'
			],
			'lot_code_rules' => [
				'char_list' => 'ABCDEFGHJKLMNPQRSTUVWXYZ123456789',
				'final_length' => 32,
				'crc_length' => 0,
				'group_length' => 0,
				'group_separator' => '.'
			],
		];
		ptcp_update_object( $data, $Events->purge_data( $eventData ) );
		$data['naming_rules']['counter_width'] = strlen( $data['estimated_turnout'] );
		$data['shortcode'] = $Shortcoder->create( $id, 'events' );
		$Events->update_calculated_fields( $data );
		$fileName = date( 'Ymd-His', $Timestamp ) . '-event-definition';
		$receipt->set( 'Message-Type', 'event-definition-confirmation' );
		$receipt->set( 'Event-Data', $data );
		if ( $votings = $message->get('Votings') ){
			$results = self::process_votings_list( $id, $votings, $sender );
			$receipt->set( 'Votings-Results', $results );
		}
		$receiptString = $receipt->dump( TRUE );
		$FileSystem->put_contents( "{$dir}/{$fileName}", $receiptString );
		return $receiptString;
	}


	static function handle_lc_event_update_request( $message, $receipt ){
		global $Events, $FileSystem, $Timestamp;

		$eventId = $message->get('Event-Id');
		$eventData = $Events->get_data( $eventId );
		if ( ! $eventData ){
			$receipt->set_rejection( 41, sprintf( _('Event %s does not exist'), $eventId ) );
			return $receipt->dump( TRUE );
		}
		$eventDir = $Events->get_dir( $eventId );
		$object = [ 'type' => 'event', 'id' => $eventId, 'dir' => $eventDir ];
		$sender = $message->get('From');
		if ( ! ptcp_is_authorized( $sender, 'event-update-request', $object ) ){
			$receipt->set_rejection( 31, _('Sender is not authorized to update event') );
			return $receipt->dump( TRUE );
		}

		$stats = $Events->get_statistics( $eventId );
		$newData = $message->get('Event-Data');
		if ( ! empty( $stats['lots_created'] ) ){
			// some data must not be changed after first lot generation
			unset( $newData['estimated_turnout'], $newData['naming_rules'],
				$newData['credential_rules'], $newData['lot_code_rules'] );
		}
		unset( $newData['date'], $newData['shortcode'] );
		ptcp_update_object( $eventData, $Events->purge_data( $newData ) );
		$Events->update_calculated_fields( $eventData );
		$eventData['modified_on'] = date( 'c', $Timestamp );
		$eventData['modified_by'] = $sender;
		$receipt->set( 'Message-Type', 'event-update-confirmation' );
		$receipt->set( 'Event-Data', $eventData );
		if ( $votings = $message->get('Votings') ){
			$results = self::process_votings_list( $eventId, $votings, $sender );
			$receipt->set( 'Votings-Results', $results );
		}
		$fileName = date( 'Ymd-His', $Timestamp ) . '-event-update-request';
		$receiptString = $receipt->dump( TRUE );
		$FileSystem->put_contents( "{$eventDir}/{$fileName}", $receiptString );
		return $receiptString;
	}


	static function handle_lc_event_list_request( $message, $receipt ){
		global $Events, $FileSystem, $Groups, $Votings;
		if ( is_object( $Groups ) && ( $groupId = $message->get('Group-Id') )
			&& ( ! $groupData = $Groups->get_data( $groupId ) )
		){
			$receipt->set_rejection( 41, sprintf( _('Group %s does not exist'), $groupId ) );
			return $receipt->dump( TRUE );
		}
		$receipt->set( 'Message-Type', 'event-list' );
		$eventList = $Events->get_list( $groupId );
		if ( $message->get('Include-Subgroups') && is_object( $Groups ) ){
			$groupList = $Groups->get_id_list_recursive( $groupId );
			foreach ( $groupList as $groupId ){
				$eventList = array_merge( $eventList, $Events->get_list( $groupId ) );
			}
		}
		$sender = $message->get('From');
		if ( $sender ){
			list ( $ptcpId, $server ) = explode( '@', $sender ) + ['',''];
		}
		$includeVotingCount = $message->get('Include-Voting-Count');
		$includeOpenVotings = $message->get('Include-Open-Votings');
		$includeAdminInfo = $message->get('Include-Admin-Info');
		$administrableOnly = $message->get('Administrable-Only');
		$finalList = [];
		foreach ( $eventList as $index => $event ){
			$eventDir = $Events->get_dir( $event['id'] );
			if ( $includeAdminInfo && $sender ){
				// TODO: Verify sender identity
				$event['administrable'] = ptcp_is_authorized( $sender, 'event-update-request',
					[ 'type' => 'event', 'id' => $event['id'], 'dir' => $eventDir ] );
			}
			if ( $includeVotingCount ){
				$Votings->set_base_dir( $eventDir );
				$event['voting_count'] = $Votings->count();
			}
			if ( $includeOpenVotings ){
				$Votings->set_base_dir( $eventDir );
				$event['open_votings'] = $Votings->get_list('open');
			}
			if ( $sender ){
				$event['lot_code_deposited'] = $FileSystem->exists( "{$eventDir}/lotcodes/{$ptcpId}" );
			}
			if ( ! $sender || ! $administrableOnly || $event['administrable'] ){
				$Events->update_calculated_fields( $event );
				$finalList[] = $event;
			}
		}
		$receipt->set( 'Events', $finalList );
		return $receipt->dump( TRUE );
	}


	static function handle_lc_event_details_request( $message, $receipt ){
		global $Events, $Shortcoder, $Votings;
		$eventId = $message->get('Event-Id');
		if ( $eventId[0] == '#' ){
			$eventId = $Shortcoder->resolve( $eventId, 'events' );
		}
		$eventData = $Events->get_data( $eventId );
		if ( ! $eventData ){
			$receipt->set_rejection( 41, _('Event does not exist') );
			return $receipt->dump( TRUE );
		}
		$eventDir = $Events->get_dir( $eventId );
		if ( $sender = $message->get('From') ){
			$eventData['administrable'] = ptcp_is_authorized( $sender, 'event-update-request',
				[ 'type' => 'event', 'id' => $eventId, 'dir' => $eventDir ] );
		}
		$Events->update_calculated_fields( $eventData );
		$Votings->set_base_dir( $eventDir );
		$receipt->set( 'Message-Type', 'event-details' );
		$receipt->set( 'Event-Data', $eventData );
		$receipt->set( 'Votings', $Votings->get_list( 'all', 'created_on' ) );
		$receipt->set( 'Participants', $Events->get_statistics( $eventId ) );
		return $receipt->dump( TRUE );
	}


	static function handle_lc_lot_code_request( $message, $receipt ){
		global $Events, $FileSystem;

		$eventId = $message->get('Event-Id');
		$eventData = $Events->get_data( $eventId );
		if ( ! $eventData ){
			$receipt->set_rejection( 41, sprintf( _('Event %s does not exist'), $eventId ) );
			return $receipt->dump( TRUE );
		}
		$sender = $message->get('From');
		list ( $ptcpId, $server ) = explode( '@', $sender ) + ['',''];
		$eventDir = $Events->get_dir( $eventId );
		$counter = 0;
		$file = "{$eventDir}/lotcodes/{$ptcpId}";
		while ( $FileSystem->exists( $file ) ) {
			$counter++;
			$nextFile = "{$eventDir}/lotcodes/{$ptcpId}-{$counter}";
			if ( ! $FileSystem->exists( $nextFile ) ){
				break;
			}
			$file = $nextFile;
		}
		if ( ! $counter ){
			$receipt->set_rejection( 42, sprintf( _('No lot code deposited for %s'), $ptcpId ) );
			return $receipt->dump( TRUE );
		}
		if ( ! ( $msg = yaml_parse( $FileSystem->get_contents( $file ) ) )
			|| empty( $msg['Original-Message'] )
			|| ! ( $msg = yaml_parse( $msg['Original-Message'] ) )
			|| ( empty ( $msg['Lot-Code'] ) && empty( $msg['Lot-Code~'] ) )
		){
			$receipt->set_failure( sprintf( _('Could not load lot code for %s'), $sender ) );
			return $receipt->dump( TRUE );
		}
		$receipt->set( 'Message-Type', 'lot-code' );
		$receipt->set( 'Lot-Code~', $msg['Lot-Code'] ?? $msg['Lot-Code~'] );
		$receipt->set( 'Original-Sender', $msg['From'] );
		$receipt->set( 'Original-Public-Key', $msg['Public-Key'] );
		return $receipt->dump( TRUE );
	}

}

// end of file lc_service.messages.class.php