<?php

	namespace arashrasoulzadeh\auth\src\traits;

	use arashrasoulzadeh\auth\src\model\UserAuthMetas;

	trait ModelMetaTrait
	{

		public $autoExclude = false;

		public $is_auto_excluded = false;


		public $check_for_duplicate = true;

		public $additionalExcludedMetas = [ "created_at" , "updated_at" ];
		/** @var array
		 * used by caching system
		 */
		private $fieldCaches = [

		];

		/**
		 * @inheritDoc
		 */
		public function __get ( $key )
		{


			$this->refreshAutoExcludes();
			$original = parent::__get( $key );
			if ( !in_array( $key , $this->excludeInMeta() ) ) {

				if ( !isset( $this->fieldCaches[ $key ] ) ) {
					$value = $this->loadFromDatabase( $key );
					$this->fieldCaches[ $key ] = $this->purifyValue( $value );
					return $this->fieldCaches[ $key ];
				}
				else {
					return $this->fieldCaches[ $key ];
				}


			}
			else {
				return $original;
			}

		}

		/**
		 * @inheritDoc
		 */
		public function __set ( $key , $value )
		{
			if ( is_array( $value ) ) {
				$value = json_encode( $value );
			}
			$this->refreshAutoExcludes();
			$original = parent::__get( $key );
			if ( !in_array( $key , $this->excludeInMeta() ) ) {
				$last = $this->$key;
				if ( $this->check_for_duplicate ) {
					if ( $last != $value ) {
						$this->saveToDatabase( $key , $value );
						$this->fieldCaches[ $key ] = $value;
					}
				}
				else {
					$this->saveToDatabase( $key , $value );
					$this->fieldCaches[ $key ] = $value;
				}
				parent::__set( $key , $value );
			}
			else {
				parent::__set( $key , $value );
			}
		}

		public function refreshAutoExcludes ()
		{
			try {
				if ( $this->autoExclude && !$this->is_auto_excluded ) {
					$this->is_auto_excluded = true;
					$sample = $this->all()->first();
					if ( !is_null( $sample ) ) {
						$attributes = $sample->getAttributes();
						$this->additionalExcludedMetas[] = array_keys( $attributes );
					}

				}
			} catch ( \Exception $exception ) {

			}
		}

		/**
		 * @return array
		 * this function keys will NOT be loaded from metas
		 */
		public function excludeInMeta ()
		{
			return array_merge( [] , $this->additionalExcludedMetas );
		}

		/**
		 * load the key from database
		 *
		 * @param $key
		 *
		 * @return string|null
		 */
		public function loadFromDatabase ( $key )
		{
			$item = UserAuthMetas
				::where( "class" , $this->table )
				->where( "key" , $key )
				->orderBy( "id" , "desc" )
				->where( "owner" , $this->id )
			;
			if ( $item->count() ) {
				$item = $item->first();
				$fresh = $item->fresh();
				return $fresh->value;
			}
			else {
				return null;
			}
		}

		/**
		 * reformat value
		 *
		 * @param $value
		 *
		 * @return string|array
		 */
		private function purifyValue ( $value )
		{
			$result = json_decode( $value , true );
			if ( json_last_error() == JSON_ERROR_NONE ) {
				return $result;
			}
			else {
				return $value;
			}
		}

		/**
		 * save the key to database
		 *
		 * @param $key
		 * @param $value
		 */
		private function saveToDatabase ( $key , $value )
		{
			$item = new UserAuthMetas();
			$item->class = $this->table;
			$item->owner = $this->id;
			$item->key = $key;
			$item->value = $value;
			$item->save();
		}

		/**
		 *
		 */
		public function getMetas ()
		{
			$metas = UserAuthMetas
				::where( "class" , $this->table )
				->where( "owner" , $this->id )
				->orderBy( 'created_at' , 'desc' )
				->get()
				->unique( 'key' )
			;

			return $metas;
		}
	}