<?php

/*
 *
 *  ____            _        _   __  __ _                  __  __ ____
 * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
 * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
 * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
 * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * @author PocketMine Team
 * @link http://www.pocketmine.net/
 *
 *
*/

declare(strict_types=1);

namespace pocketmine\network\mcpe\protocol;

#include <rules/DataPacket.h>

use pocketmine\entity\Attribute;
use pocketmine\entity\Entity;
use pocketmine\item\ItemFactory;
use pocketmine\math\Vector3;
use pocketmine\network\mcpe\NetworkSession;
use pocketmine\network\mcpe\protocol\types\EntityLink;
use pocketmine\utils\BinaryStream;
use pocketmine\utils\Utils;


abstract class DataPacket extends BinaryStream{

	const NETWORK_ID = 0;

	/** @var bool */
	public $isEncoded = false;

	/** @var int */
	public $extraByte1 = 0;
	/** @var int */
	public $extraByte2 = 0;

	public function pid(){
		return $this::NETWORK_ID;
	}

	public function getName() : string{
		return (new \ReflectionClass($this))->getShortName();
	}

	public function canBeBatched() : bool{
		return true;
	}

	public function canBeSentBeforeLogin() : bool{
		return false;
	}

	/**
	 * Returns whether the packet may legally have unread bytes left in the buffer.
	 * @return bool
	 */
	public function mayHaveUnreadBytes() : bool{
		return false;
	}

	public function decode(){
		$this->offset = 0;
		$this->decodeHeader();
		$this->decodePayload();
	}

	protected function decodeHeader(){
		$pid = $this->getUnsignedVarInt();
		assert($pid === static::NETWORK_ID);

		$this->extraByte1 = $this->getByte();
		$this->extraByte2 = $this->getByte();
		assert($this->extraByte1 === 0 and $this->extraByte2 === 0, "Got unexpected non-zero split-screen bytes (byte1: $this->extraByte1, byte2: $this->extraByte2");
	}

	/**
	 * Note for plugin developers: If you're adding your own packets, you should perform decoding in here.
	 */
	protected function decodePayload(){

	}

	public function encode(){
		$this->reset();
		$this->encodeHeader();
		$this->encodePayload();
		$this->isEncoded = true;
	}

	protected function encodeHeader(){
		$this->putUnsignedVarInt(static::NETWORK_ID);

		$this->putByte($this->extraByte1);
		$this->putByte($this->extraByte2);
	}

	/**
	 * Note for plugin developers: If you're adding your own packets, you should perform encoding in here.
	 */
	protected function encodePayload(){

	}

	/**
	 * Performs handling for this packet. Usually you'll want an appropriately named method in the NetworkSession for this.
	 *
	 * This method returns a bool to indicate whether the packet was handled or not. If the packet was unhandled, a debug message will be logged with a hexdump of the packet.
	 * Typically this method returns the return value of the handler in the supplied NetworkSession. See other packets for examples how to implement this.
	 *
	 * @param NetworkSession $session
	 *
	 * @return bool true if the packet was handled successfully, false if not.
	 */
	abstract public function handle(NetworkSession $session) : bool;

	public function clean(){
		$this->buffer = null;
		$this->isEncoded = false;
		$this->offset = 0;
		return $this;
	}

	public function __debugInfo(){
		$data = [];
		foreach($this as $k => $v){
			if($k === "buffer" and is_string($v)){
				$data[$k] = bin2hex($v);
			}elseif(is_string($v) or (is_object($v) and method_exists($v, "__toString"))){
				$data[$k] = Utils::printable((string) $v);
			}else{
				$data[$k] = $v;
			}
		}

		return $data;
	}

	/**
	 * Decodes entity metadata from the stream.
	 *
	 * @param bool $types Whether to include metadata types along with values in the returned array
	 *
	 * @return array
	 */
	public function getEntityMetadata(bool $types = true) : array{
		$count = $this->getUnsignedVarInt();
		$data = [];
		for($i = 0; $i < $count; ++$i){
			$key = $this->getUnsignedVarInt();
			$type = $this->getUnsignedVarInt();
			$value = null;
			switch($type){
				case Entity::DATA_TYPE_BYTE:
					$value = $this->getByte();
					break;
				case Entity::DATA_TYPE_SHORT:
					$value = $this->getSignedLShort();
					break;
				case Entity::DATA_TYPE_INT:
					$value = $this->getVarInt();
					break;
				case Entity::DATA_TYPE_FLOAT:
					$value = $this->getLFloat();
					break;
				case Entity::DATA_TYPE_STRING:
					$value = $this->getString();
					break;
				case Entity::DATA_TYPE_SLOT:
					//TODO: use objects directly
					$value = [];
					$item = $this->getSlot();
					$value[0] = $item->getId();
					$value[1] = $item->getCount();
					$value[2] = $item->getDamage();
					break;
				case Entity::DATA_TYPE_POS:
					$value = [0, 0, 0];
					$this->getSignedBlockPosition(...$value);
					break;
				case Entity::DATA_TYPE_LONG:
					$value = $this->getVarLong();
					break;
				case Entity::DATA_TYPE_VECTOR3F:
					$value = [0.0, 0.0, 0.0];
					$this->getVector3f(...$value);
					break;
				default:
					$value = [];
			}
			if($types === true){
				$data[$key] = [$type, $value];
			}else{
				$data[$key] = $value;
			}
		}

		return $data;
	}

	/**
	 * Writes entity metadata to the packet buffer.
	 *
	 * @param array $metadata
	 */
	public function putEntityMetadata(array $metadata){
		$this->putUnsignedVarInt(count($metadata));
		foreach($metadata as $key => $d){
			$this->putUnsignedVarInt($key); //data key
			$this->putUnsignedVarInt($d[0]); //data type
			switch($d[0]){
				case Entity::DATA_TYPE_BYTE:
					$this->putByte($d[1]);
					break;
				case Entity::DATA_TYPE_SHORT:
					$this->putLShort($d[1]); //SIGNED short!
					break;
				case Entity::DATA_TYPE_INT:
					$this->putVarInt($d[1]);
					break;
				case Entity::DATA_TYPE_FLOAT:
					$this->putLFloat($d[1]);
					break;
				case Entity::DATA_TYPE_STRING:
					$this->putString($d[1]);
					break;
				case Entity::DATA_TYPE_SLOT:
					//TODO: change this implementation (use objects)
					$this->putSlot(ItemFactory::get($d[1][0], $d[1][2], $d[1][1])); //ID, damage, count
					break;
				case Entity::DATA_TYPE_POS:
					//TODO: change this implementation (use objects)
					$this->putSignedBlockPosition(...$d[1]);
					break;
				case Entity::DATA_TYPE_LONG:
					$this->putVarLong($d[1]);
					break;
				case Entity::DATA_TYPE_VECTOR3F:
					//TODO: change this implementation (use objects)
					$this->putVector3f(...$d[1]); //x, y, z
			}
		}
	}

	/**
	 * Reads a list of Attributes from the stream.
	 * @return Attribute[]
	 *
	 * @throws \UnexpectedValueException if reading an attribute with an unrecognized name
	 */
	public function getAttributeList() : array{
		$list = [];
		$count = $this->getUnsignedVarInt();

		for($i = 0; $i < $count; ++$i){
			$min = $this->getLFloat();
			$max = $this->getLFloat();
			$current = $this->getLFloat();
			$default = $this->getLFloat();
			$name = $this->getString();

			$attr = Attribute::getAttributeByName($name);
			if($attr !== null){
				$attr->setMinValue($min);
				$attr->setMaxValue($max);
				$attr->setValue($current);
				$attr->setDefaultValue($default);

				$list[] = $attr;
			}else{
				throw new \UnexpectedValueException("Unknown attribute type \"$name\"");
			}
		}

		return $list;
	}

	/**
	 * Writes a list of Attributes to the packet buffer using the standard format.
	 * @param Attribute[] ...$attributes
	 */
	public function putAttributeList(Attribute ...$attributes){
		$this->putUnsignedVarInt(count($attributes));
		foreach($attributes as $attribute){
			$this->putLFloat($attribute->getMinValue());
			$this->putLFloat($attribute->getMaxValue());
			$this->putLFloat($attribute->getValue());
			$this->putLFloat($attribute->getDefaultValue());
			$this->putString($attribute->getName());
		}
	}

	/**
	 * Reads and returns an EntityUniqueID
	 * @return int
	 */
	public function getEntityUniqueId() : int{
		return $this->getVarLong();
	}

	/**
	 * Writes an EntityUniqueID
	 * @param int $eid
	 */
	public function putEntityUniqueId(int $eid){
		$this->putVarLong($eid);
	}

	/**
	 * Reads and returns an EntityRuntimeID
	 * @return int
	 */
	public function getEntityRuntimeId() : int{
		return $this->getUnsignedVarLong();
	}

	/**
	 * Writes an EntityUniqueID
	 * @param int $eid
	 */
	public function putEntityRuntimeId(int $eid){
		$this->putUnsignedVarLong($eid);
	}

	/**
	 * Reads an block position with unsigned Y coordinate.
	 * @param int &$x
	 * @param int &$y
	 * @param int &$z
	 */
	public function getBlockPosition(&$x, &$y, &$z){
		$x = $this->getVarInt();
		$y = $this->getUnsignedVarInt();
		$z = $this->getVarInt();
	}

	/**
	 * Writes a block position with unsigned Y coordinate.
	 * @param int $x
	 * @param int $y
	 * @param int $z
	 */
	public function putBlockPosition(int $x, int $y, int $z){
		$this->putVarInt($x);
		$this->putUnsignedVarInt($y);
		$this->putVarInt($z);
	}

	/**
	 * Reads a block position with a signed Y coordinate.
	 * @param int &$x
	 * @param int &$y
	 * @param int &$z
	 */
	public function getSignedBlockPosition(&$x, &$y, &$z){
		$x = $this->getVarInt();
		$y = $this->getVarInt();
		$z = $this->getVarInt();
	}

	/**
	 * Writes a block position with a signed Y coordinate.
	 * @param int $x
	 * @param int $y
	 * @param int $z
	 */
	public function putSignedBlockPosition(int $x, int $y, int $z){
		$this->putVarInt($x);
		$this->putVarInt($y);
		$this->putVarInt($z);
	}

	/**
	 * Reads a floating-point vector3 rounded to 4dp.
	 * @param float $x
	 * @param float $y
	 * @param float $z
	 */
	public function getVector3f(&$x, &$y, &$z){
		$x = $this->getRoundedLFloat(4);
		$y = $this->getRoundedLFloat(4);
		$z = $this->getRoundedLFloat(4);
	}

	/**
	 * Writes a floating-point vector3
	 * @param float $x
	 * @param float $y
	 * @param float $z
	 */
	public function putVector3f(float $x, float $y, float $z){
		$this->putLFloat($x);
		$this->putLFloat($y);
		$this->putLFloat($z);
	}

	/**
	 * Reads a floating-point Vector3 object
	 * TODO: get rid of primitive methods and replace with this
	 *
	 * @return Vector3
	 */
	public function getVector3Obj() : Vector3{
		return new Vector3(
			$this->getRoundedLFloat(4),
			$this->getRoundedLFloat(4),
			$this->getRoundedLFloat(4)
		);
	}

	/**
	 * Writes a floating-point Vector3 object, or 3x zero if null is given.
	 *
	 * Note: ONLY use this where it is reasonable to allow not specifying the vector.
	 * For all other purposes, use {@link DataPacket#putVector3Obj}
	 *
	 * @param Vector3|null $vector
	 */
	public function putVector3ObjNullable(Vector3 $vector = null){
		if($vector){
			$this->putVector3Obj($vector);
		}else{
			$this->putLFloat(0.0);
			$this->putLFloat(0.0);
			$this->putLFloat(0.0);
		}
	}

	/**
	 * Writes a floating-point Vector3 object
	 * TODO: get rid of primitive methods and replace with this
	 *
	 * @param Vector3 $vector
	 */
	public function putVector3Obj(Vector3 $vector){
		$this->putLFloat($vector->x);
		$this->putLFloat($vector->y);
		$this->putLFloat($vector->z);
	}

	public function getByteRotation() : float{
		return (float) ($this->getByte() * (360 / 256));
	}

	public function putByteRotation(float $rotation){
		$this->putByte((int) ($rotation / (360 / 256)));
	}

	/**
	 * Reads gamerules
	 * TODO: implement this properly
	 *
	 * @return array
	 */
	public function getGameRules() : array{
		$count = $this->getUnsignedVarInt();
		$rules = [];
		for($i = 0; $i < $count; ++$i){
			$name = $this->getString();
			$type = $this->getUnsignedVarInt();
			$value = null;
			switch($type){
				case 1:
					$value = $this->getBool();
					break;
				case 2:
					$value = $this->getUnsignedVarInt();
					break;
				case 3:
					$value = $this->getLFloat();
					break;
			}

			$rules[$name] = [$type, $value];
		}

		return $rules;
	}

	/**
	 * Writes a gamerule array
	 * TODO: implement this properly
	 *
	 * @param array $rules
	 */
	public function putGameRules(array $rules){
		$this->putUnsignedVarInt(count($rules));
		foreach($rules as $name => $rule){
			$this->putString($name);
			$this->putUnsignedVarInt($rule[0]);
			switch($rule[0]){
				case 1:
					$this->putBool($rule[1]);
					break;
				case 2:
					$this->putUnsignedVarInt($rule[1]);
					break;
				case 3:
					$this->putLFloat($rule[1]);
					break;
			}
		}
	}

	/**
	 * @return EntityLink
	 */
	protected function getEntityLink() : EntityLink{
		$link = new EntityLink();
		$link->fromEntityUniqueId = $this->getEntityUniqueId();
		$link->toEntityUniqueId = $this->getEntityUniqueId();
		$link->type = $this->getByte();
		$link->byte2 = $this->getByte();

		return $link;
	}

	/**
	 * @param EntityLink $link
	 */
	protected function putEntityLink(EntityLink $link){
		$this->putEntityUniqueId($link->fromEntityUniqueId);
		$this->putEntityUniqueId($link->toEntityUniqueId);
		$this->putByte($link->type);
		$this->putByte($link->byte2);

	}
}