<?php
	namespace Juju\Net;
	use Juju\Events;
	require_once(dirname(__DIR__).'/events.trait.php');

	class Socket {
		use Events;
		private $socket;
		private $clients;
		private $dsn;
		private $socket_type;
		private $open;
		const SERVER = 0;
		const CLIENT = 1;
		public static function from(string $dsnstring, bool $listen = false){
			return new Socket($dsnstring, $listen);
		}
		private function __construct(string $dsnstring, bool $listen = false){
			$parts = explode('://', $dsnstring);
			$dsnstring = $parts[1];
			$dsn = explode(';', $dsnstring);
			$dsn = array_reduce($dsn, function($dsn, $item){
				$item = explode('=', $item);
				$dsn[$item[0]] = $item[1];
				return $dsn;
			});
			$this->dsn = [
				'protocol'=> $parts[0] ?? null,
				'domain'=> strtoupper($dsn['domain']) ?? 'UNIX',
				'type'=> strtoupper($dsn['type']) ?? 'STREAM',
				'address'=> $dsn['address'] ?? '127.0.0.1',
				'port'=> $dsn['port'] ?? null,
				'max_connections'=> $dsn['max_connections'] ?? 5
			];
			$this->socket_type = $listen ? static::SERVER : static::CLIENT;
			$this->open = false;
			if($listen){
				$this->clients = [];
			}
		}
		public function __get($name){
			switch($name){
				case 'socket':case 'dsn':case 'socket_type':case 'open':
					return $this->$name;
				break;
				case 'protocol':case 'domain':case 'type':case 'address':case 'port':case 'max_connections':
					return $this->dsn[$name];
				break;
				case 'error':
					return socket_strerror(socket_last_error());
				break;
				default:
					throw new \Exception("Property {$name} does not exist");
			}
		}
		public function __set($name, $value){
			throw new \Exception("Property {$name} does not exist or is read only");
		}
		private function throw_if($bool){
			if($bool === false){
				$this->throw();
			}
		}
		private function throw(){
			$error = new \Exception($this->error);
			if($this->fire('error', $this, $error) !== false){
				throw $error;
			}
		}
		public function open(){
			$this->socket = socket_create(constant("AF_{$this->dsn['protocol']}"), constant("SOCK_{$this->dsn['type']}"), is_null($this->dsn['protocol']) ? 0 : getprotobyname($this->dsn['protocol']));
			$this->throw_if($this->socket);
			if($this->socket_type == static::SERVER){
				if(is_null($this->port)){
					socket_bind($this->socket, $this->address);
				}else{
					$res = socket_bind($this->socket, $this->address, $this->port);
				}
				$this->throw_if($res);
				$this->fire('bind', $this);
				$this->throw_if(socket_listen($this->socket, $this->max_connections));
				$this->fire('listen', $this);
			}elseif($this->socket_type == static::CLIENT){
				if(is_null($this->port)){
					socket_connect($this->socket, $this->address);
				}else{
					$res = socket_connect($this->socket, $this->address, $this->port);
				}
				$this->throw_if($res);
			}else{
				throw new \Exception("Invalid socket type {$this->socket_type}");
			}
			$this->open = true;
			$this->fire('open', $this);
			return $this;
		}
		public function handle(int $length = 2048, bool $binary = false){
			if(!$this->open){
				$this->open();
			}
			socket_set_nonblock($this->socket);
			if($this->socket_type == static::SERVER){
				$regex = $binary ? '/\0/' : '/[\n\r]/';
				$type = $binary ? PHP_BINARY_READ : PHP_NORMAL_READ;
				do{
					$socket = socket_accept($this->socket);
					if($socket === false){
						usleep(100);
					}elseif($socket  > 0){
						socket_set_nonblock($socket);
						$client = [$socket, ''];
						$this->clients[] = $client;
						$this->fire('connect', $this, $client);
					}else{
						$error = trim(socket_strerror($socket));
						if($error !== 'A non-blocking socket operation could not be completed immediately.'){
							$this->fire('error', $this, new \Exception($error));
							$this->open = false;
						}
					}
					$this->fire('tick', $this);
					if($this->open){
						foreach($this->clients as $client){
							$data = socket_read($client[0], $length, $type);
							if($data === false){
								$this->drop($client);
							}else{
								if(strlen($data) > 0 && $this->fire('data', $this, $data, $client) !== false){
									$client[1] .= $data;
								}
								$pos = preg_match($regex, $data, $matches, PREG_OFFSET_CAPTURE) == 1 ? $matches[0][1] : false;
								if($pos === strlen($data) - 1){
									$this->fire('read', $this, substr($client[1], 0, -1), $client);
									$client[1] = '';
								}
							}
							$this->fire('tick', $this);
							if($this->open === false){
								break;
							}
						}
					}
				}while($this->open);
			}elseif($this->socket_type == static::CLIENT){
				while($this->open && $this->read($length, $binary) !== false){};
			}
			socket_set_block($this->socket);
			$this->close(true);
			return $this;
		}
		public function write(string $data, bool $binary = false){
			if(!$this->open){
				throw new \Exception("You can't write to a socket that isn't open");
			}
			$stop = $binary ? "\0" : "\n";
			if($this->fire('write', $this, $data) !== false){
				$this->throw_if(socket_write($this->socket, $data.$stop));
			}
			return $this;
		}
		public function read(int $length = 2048, bool $binary = false){
			if(!$this->open){
				return false;
			}
			$regex = $binary ? '/\0/' : '/[\n\r]/';
			$type = $binary ? PHP_BINARY_READ : PHP_NORMAL_READ;
			$line = '';
			do{
				$data = socket_read($this->socket, $length, $type);
				if($data === false){
					$this->open = false;
				}elseif(strlen($data) > 0 && $this->fire('data', $this, $data) !== false){
					$line .= $data;
				}
				$pos = preg_match($regex, $data, $matches, PREG_OFFSET_CAPTURE) == 1 ? $matches[0][1] : false;
			}while($pos !== strlen($data) - 1 && $this->open !== false);
			$line = substr($line, 0, -1);
			$this->fire('read', $this, $line);
			return $line;
		}
		public function client_write(array $client, $data, bool $binary = false){
			if(!$this->open){
				throw new \Exception("You can't write to a socket that isn't open");
			}
			$stop = $binary ? "\0" : "\n";
			if($this->fire('write', $this, $data) !== false){
				$this->throw_if(socket_write($client[0], $data.$stop));
			}
			return $this;
		}
		public function close(bool $event = false){
			foreach($this->clients as $client){
				$this->drop($client);
			}
			socket_close($this->socket);
			$this->open = false;
			$this->fire('close', $this);
			return $this;
		}
		public function drop($client){
			socket_close($client[0]);
			if(in_array($client, $this->clients)){
				array_splice($this->clients, array_search($client, $this->clients), 1);
				$this->fire('disconnect', $this, $client);
			}
		}
	}
?>