Managing complex datastructures with a class

class-collectionmanager.php

<?php
class CollectionManagement
{
	/**
	 * Option key
	 * @var string
	 */
	const OPTION_KEY = 'collection_settings';

	/**
	 * Collections from DB
	 * @var array
	 */
	public $collections = array();

	/**
	 * Results of methods
	 * @var boolean|array
	 */
	public $result = null;

	/**
	 * Get the collections from db on creating an instance
	 */
	public function __construct(){

		$this->get_collections_from_db();

	}

	/**
	 * Write collections to db on destruction
	 */
	public function __destruct(){

		$this->store_colletion_to_db();

	}

	/**
	 * Reset the internal result, get collections from db if not already done
	 */
	protected function reset(){

		if( empty( $this->collections ) )
			$this->get_collections_from_db();

		$this->result = false;

		return ( ! empty( $this->collections ) );

	}

	/**
	 * Get a collection by it's id
	 * @param string $id ID of the collection
	 * @param string $first_match Whether to return the first match or the last match
	 * @return boolean|array False if the collection was not found, else the (first|last) matching collection
	 */
	protected function seek_collection_by_id( $id = '', $first_match = true ){

		$result = false;

		foreach( $this->collections as $collection ){

			if( isset( $collection[$id] ) && $id === $collection[$id] ){

				$result = $collection;

				if( true === $first_match )
					break;

			}

		}

		return $result;

	}

	/**
	 * Store collections in db
	 * @return boolean Always true
	 */
	public function store_colletions_to_db(){

		update_option( self::OPTION_KEY, $this->collections );

		return true;

	}

	/**
	 * Get the collections from db
	 * @return boolean Always true
	 */
	public function get_collections_from_db(){

		$this->collections = get_option( self::OPTION_KEY );

		return true;

	}

	/**
	 * Update a collection
	 * @param array $collection
	 * @return boolean True on success, false on error
	 */
	public function update_collection( $collection = array() ){

		if( ! is_array( $collection ) || empty( $collection ) )
			return false;

		$this->reset();

		$this->collections[$collection['id']] = $collection;

		// maybe store collections immediately
		//$this->store_colletions_to_db();

		$this->result = isset( $this->collections[$collection['id']] );
		
		return $this->result;

	}

	/**
	 * Get a collection by it's id
	 * @param string $id
	 * @return boolean|array False if the collection was not found, else the collection
	 */
	public function get_collection_by_id( $id = '' ){

		if( empty( $id ) )
			return false;

		$this->reset();

		$this->result = $this->seek_collection_by_id( $id );
		
		return $this->result;

	}

	/**
	 * Get the elements of a collection by the collection id
	 * @param string $id
	 * @return boolean|array False if the elemnts could not be found, else array with the collection elements
	 */
	public function get_elements_by_id( $id = '' ){

		if( empty( $id ) )
			return false;

		$this->reset();

		$collection = $this->seek_collection_by_id( $id );

		$this->result = $collection['elements'];

		return $this->result;

	}

	/**
	 * Insert an element-array into a collection identified by it's id
	 * @param string $id
	 * @param array $element
	 * @return string|int The id of the inserted element
	 */
	public function insert_element_by_id( $id = '', $element = array() ){

		if( empty( $id ) || empty( $element ) )
			return false;

		$element = array_merge(
				array( 'id' => 0, 'name' => '', 'url' => '' ),
				$element
		);

		$this->reset();

		$collection = $this->seek_collection_by_id( $id );

		// check elements if is an array
		if( ! is_array( $collection['elements'] ) )
			$collection['elements'] = array();

		// prevent using an id twice
		$ids = array();

		foreach( $collection['elements'] as $single_element ){

			if( isset( $single_element['id'] ) && ! empty( $single_element['id'] ) )
				array_push( $ids, $single_element['id'] );

		}

		// if the id already exists, add an random number to prevent double ids
		if( in_array( $element['id'], $ids ) )
			$element['id'] .= rand( 1, 999 );

		array_push( $collection['elements'], $element );

		$this->update_collection( $collection );

		$this->result = $element['id'];

		return $this->result;

	}

}