<?php

class Storage_DB {

	static $db;
	static $tblKeypairs = 'keypairs';
	static $tblPubkeys = 'pubkeys';

	static function store_pubkey( $id, $pubkey ){
		$tblPubkeys = self::$db->real_escape_string( self::$tblPubkeys );
		$id = self::$db->real_escape_string( $id );
		$pubkey = self::$db->real_escape_string( $pubkey );
		$sql = "INSERT INTO `{$tblPubkeys}` SET
			`id` = '{$id}', `pubkey` = '{$pubkey}'
			ON DUPLICATE KEY UPDATE `pubkey` = '{$pubkey}'";
		$result = self::$db->query( $sql );
		if ( ! $result || ! self::$db->affected_rows ){
			throw new Exception('Could not store public key');
		}
	}


	static function get_pubkey( $id ){
		$tblPubkeys = self::$db->real_escape_string( self::$tblPubkeys );
		$id = self::$db->real_escape_string( $id );
		$sql = "SELECT `pubkey` FROM `{$tblPubkeys}`
			WHERE `id` = '{$id}'";
		$result = self::$db->query( $sql );
		if ( ! $result || ! $result->num_rows ){
			return FALSE;
		}
		$row = $result->fetch_assoc();
		return $row['pubkey'];
	}


	static function store_keypair( $id, $pubkey, $privkey, $overwrite = FALSE ){
		$tblKeypairs = self::$db->real_escape_string( self::$tblKeypairs );
		$pubkey = self::$db->real_escape_string( $pubkey );
		$privkey = self::$db->real_escape_string( $privkey );
		$sql = "INSERT INTO `{$tblKeypairs}` SET
			`id` = '{$id}', `pubkey` = '{$pubkey}', `privkey` = '{$privkey}'";
		if ( $overwrite ){
			$sql .= " ON DUPLICATE KEY UPDATE
				`pubkey` = '{$pubkey}', `privkey` = '{$privkey}'";
		}
		$result = self::$db->query( $sql );
		if ( ! $result || ! self::$db->affected_rows ){
			throw new Exception('Could not insert key pair into database');
		}
	}


	static function exists_keypair( $id ){
		$tblKeypairs = self::$db->real_escape_string( self::$tblKeypairs );
		$id = self::$db->real_escape_string( $id );
		$sql = "SELECT 1 FROM `{$tblKeypairs}` WHERE `id` = '{$id}'";
		$result = self::$db->query( $sql );
		return $result && $result->num_rows > 0;
	}


	static function get_keypair( $id ){
		$tblKeypairs = self::$db->real_escape_string( self::$tblKeypairs );
		$id = self::$db->real_escape_string( $id );
		$sql = "SELECT `pubkey`, `privkey` FROM `{$tblKeypairs}`
			WHERE `id` = '{$id}'";
		$result = self::$db->query( $sql );
		if ( ! $result || ! $result->num_rows ){
			return FALSE;
		}
		$row = $result->fetch_assoc();
		return [ $row['pubkey'], $row['privkey'] ];
	}


	static function remove_keypair( $id ){
		$tblKeypairs = self::$db->real_escape_string( self::$tblKeypairs );
		$id = self::$db->real_escape_string( $id );
		$sql = "DELETE FROM `{$tblKeypairs}` WHERE `id` = '{$id}'";
		self::$db->query( $sql );
		return self::$db->affected_rows;
	}


	static function list_keypairs( $pattern = NULL ){
		$tblKeypairs = self::$db->real_escape_string( self::$tblKeypairs );
		$sql = "SELECT `id` FROM `{$tblKeypairs}`";
		if ( $pattern ){
			$pattern = self::$db->real_escape_string( $pattern );
			$sql .= " WHERE `id` LIKE '{$pattern}%'";
		}
		$result = self::$db->query( $sql );
		if ( ! $result || ! $result->num_rows ){
			return [];
		}
		$list = [];
		while ( $row = $result->fetch_row() ){
			$list[] = implode( $row );
		}
		return $list;
	}

}


// end of file storage_db.class.php