/app/code/core/Mage/Catalog/Model/Category/Api.php

<?php
/**
 * Magento
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Open Software License (OSL 3.0)
 * that is bundled with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://opensource.org/licenses/osl-3.0.php
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@magentocommerce.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade Magento to newer
 * versions in the future. If you wish to customize Magento for your
 * needs please refer to http://www.magentocommerce.com for more information.
 *
 * @category   Mage
 * @package    Mage_Catalog
 * @copyright  Copyright (c) 2008 Irubin Consulting Inc. DBA Varien (http://www.varien.com)
 * @license    http://opensource.org/licenses/osl-3.0.php  Open Software License (OSL 3.0)
 */

/**
 * Catalog category api
 *
 * @category   Mage
 * @package    Mage_Catalog
 * @author     Magento Core Team <core@magentocommerce.com>
 */
class Mage_Catalog_Model_Category_Api extends Mage_Catalog_Model_Api_Resource
{
    public function __construct()
    {
        $this->_storeIdSessionField = 'category_store_id';
    }

    /**
     * Retrive level of categories for category/store view/website
     *
     * @param string|int $website
     * @param string|int $store
     * @return array
     */
    public function level($website = null, $store = null, $categoryId = null)
    {
        $ids = array();
        $storeId = Mage_Catalog_Model_Category::DEFAULT_STORE_ID;

        // load root categories of website
        if (null !== $website) {
            try {
                $website = Mage::app()->getWebsite($website);
                foreach ($website->getStores() as $store) {
                    /* @var $store Mage_Core_Model_Store */
                    $ids[] = $store->getRootCategoryId();
                }
            } catch (Mage_Core_Exception $e) {
                $this->_fault('website_not_exists', $e->getMessage());
            }
        }
        elseif (null !== $store) {
            // load children of root category of store
            if (null === $categoryId) {
                try {
                    $store = Mage::app()->getStore($store);
                    $storeId = $store->getId();
                    $ids = $store->getRootCategoryId();
                } catch (Mage_Core_Model_Store_Exception $e) {
                    $this->_fault('store_not_exists');
                }
            }
            // load children of specified category id
            else {
                $storeId = $this->_getStoreId($store);
                $ids = (int)$categoryId;
            }
        }
        // load all root categories
        else {
            $ids = Mage_Catalog_Model_Category::TREE_ROOT_ID;
        }

        $collection = Mage::getModel('catalog/category')->getCollection()
            ->setStoreId($storeId)
            ->addAttributeToSelect('name')
            ->addAttributeToSelect('is_active');

        if (is_array($ids)) {
            $collection->addFieldToFilter('entity_id', array('in' => $ids));
        } else {
            $collection->addFieldToFilter('parent_id', $ids);
        }

        // Only basic category data
        $result = array();
        foreach ($collection as $category) {
            /* @var $category Mage_Catalog_Model_Category */
            $result[] = array(
                'category_id' => $category->getId(),
                'parent_id'   => $category->getParentId(),
                'name'        => $category->getName(),
                'is_active'   => $category->getIsActive(),
                'position'    => $category->getPosition(),
                'level'       => $category->getLevel()
            );
        }

        return $result;
    }

    /**
     * Retrieve category tree
     *
     * @param int $parent
     * @param string|int $store
     * @return array
     */
    public function tree($parentId = null, $store = null)
    {
        $tree = Mage::getResourceSingleton('catalog/category_tree')
                ->load();

        if (is_null($parentId) && !is_null($store)) {
            $parentId = Mage::app()->getStore($this->_getStoreId($store))->getRootCategoryId();
        } elseif (is_null($parentId)) {
            $parentId = 1;
        }

        $tree = Mage::getResourceSingleton('catalog/category_tree')
            ->load();
        /* @var $tree Mage_Catalog_Model_Resource_Eav_Mysql4_Category_Tree */

        $root = $tree->getNodeById($parentId);

        if($root && $root->getId() == 1) {
            $root->setName(Mage::helper('catalog')->__('Root'));
        }

        $collection = Mage::getModel('catalog/category')->getCollection()
            ->setStoreId($this->_getStoreId($store))
            ->addAttributeToSelect('name')
            ->addAttributeToSelect('is_active');

        $tree->addCollectionData($collection, true);

        return $this->_nodeToArray($root);
    }

    /**
     * Convert node to array
     *
     * @param Varien_Data_Tree_Node $node
     * @return array
     */
    protected function _nodeToArray(Varien_Data_Tree_Node $node)
    {
        // Only basic category data
        $result = array();
        $result['category_id'] = $node->getId();
        $result['parent_id']   = $node->getParentId();
        $result['name']        = $node->getName();
        $result['is_active']   = $node->getIsActive();
        $result['position']    = $node->getPosition();
        $result['level']       = $node->getLevel();
        $result['children']    = array();

        foreach ($node->getChildren() as $child) {
            $result['children'][] = $this->_nodeToArray($child);
        }

        return $result;
    }

    /**
     * Initilize and return category model
     *
     * @param int $categoryId
     * @param string|int $store
     * @return Mage_Catalog_Model_Category
     */
    protected function _initCategory($categoryId, $store = null)
    {
        $category = Mage::getModel('catalog/category')
            ->setStoreId($this->_getStoreId($store))
            ->load($categoryId);

        if (!$category->getId()) {
            $this->_fault('not_exists');
        }

        return $category;
    }

    /**
     * Retrieve category data
     *
     * @param int $categoryId
     * @param string|int $store
     * @param array $attributes
     * @return array
     */
    public function info($categoryId, $store = null, $attributes = null)
    {
        $category = $this->_initCategory($categoryId, $store);

        // Basic category data
        $result = array();
        $result['category_id'] = $category->getId();

        $result['is_active']   = $category->getIsActive();
        $result['position']    = $category->getPosition();
        $result['level']       = $category->getLevel();

        foreach ($category->getAttributes() as $attribute) {
            if ($this->_isAllowedAttribute($attribute, $attributes)) {
                $result[$attribute->getAttributeCode()] = $category->getData($attribute->getAttributeCode());
            }
        }
        $result['parent_id']   = $category->getParentId();
        $result['children']           = $category->getChildren();
        $result['all_children']       = $category->getAllChildren();

        return $result;
    }

    /**
     * Create new category
     *
     * @param int $parentId
     * @param array $categoryData
     * @return int
     */
    public function create($parentId, $categoryData, $store = null)
    {
         $parent_category = $this->_initCategory($parentId);

        $category = Mage::getModel('catalog/category')
            ->setStoreId($this->_getStoreId($store));



        $category->addData(array('path'=>implode('/',$parent_category->getPathIds())));

        $category ->setAttributeSetId($category->getDefaultAttributeSetId());
        /* @var $category Mage_Catalog_Model_Category */

        foreach ($category->getAttributes() as $attribute) {
            if ($this->_isAllowedAttribute($attribute)
                && isset($categoryData[$attribute->getAttributeCode()])) {
                $category->setData(
                    $attribute->getAttributeCode(),
                    $categoryData[$attribute->getAttributeCode()]
                );
            }
        }
        $category->setParentId($parent_category->getId());
        try {
            $category->save();
        } catch (Mage_Core_Exception $e) {
            $this->_fault('data_invalid', $e->getMessage());
        }

        return $category->getId();
    }

    /**
     * Update category data
     *
     * @param int $categoryId
     * @param array $categoryData
     * @param string|int $store
     * @return boolean
     */
    public function update($categoryId, $categoryData, $store = null)
    {
        $category = $this->_initCategory($categoryId, $store);

        foreach ($category->getAttributes() as $attribute) {
            if ($this->_isAllowedAttribute($attribute)
                && isset($categoryData[$attribute->getAttributeCode()])) {
                $category->setData(
                    $attribute->getAttributeCode(),
                    $categoryData[$attribute->getAttributeCode()]
                );
            }
        }

        try {
            $category->save();
        } catch (Mage_Core_Exception $e) {
            $this->_fault('data_invalid', $e->getMessage());
        }

        return true;
    }

    /**
     * Move category in tree
     *
     * @param int $categoryId
     * @param int $parentId
     * @param int $afterId
     * @return boolean
     */
    public function move($categoryId, $parentId, $afterId = null)
    {
        $category = $this->_initCategory($categoryId);
        $parent_category = $this->_initCategory($parentId);

        $tree = Mage::getResourceModel('catalog/category_tree')
                ->load();

        $node           = $tree->getNodeById($category->getId());
        $newParentNode  = $tree->getNodeById($parent_category->getId());

        if (!$node || !$node->getId()) {
            $this->_fault('not_exists');
        }

        // if $afterId is null - move category to the down
        if ($afterId === null && $parent_category->hasChildren()) {
            $parentChildren = $parent_category->getChildren();
            $afterId = array_pop(explode(',', $parentChildren));
        }

        $prevNode = $tree->getNodeById($afterId);

        if (!$prevNode || !$prevNode->getId()) {
            $prevNode = null;
        }

        try {
            $tree->move($node, $newParentNode, $prevNode);
        } catch (Mage_Core_Exception $e) {
            $this->_fault('not_moved', $e->getMessage());
        }

        return true;
    }

    /**
     * Delete category
     *
     * @param int $categoryId
     * @return boolean
     */
    public function delete($categoryId)
    {
        $category = $this->_initCategory($categoryId);

        try {
            $category->delete();
        } catch (Mage_Core_Exception $e) {
            $this->_fault('not_deleted', $e->getMessage());
        }

        return true;
    }

    /**
     * Get prduct Id from sku or from product id
     *
     * @param int|string $productId
     * @return int
     */
    protected function _getProductId($productId)
    {
        $product = Mage::getModel('catalog/product');

        $idBySku = $product->getIdBySku($productId);
        if ($idBySku) {
            $productId = $idBySku;
        }

        $product->load($productId);

        if (!$product->getId()) {
            $this->_fault('not_exists','Product not exists.');
        }

        return $productId;
    }


    /**
     * Retrieve list of assigned products to category
     *
     * @param int $categoryId
     * @return array
     */
    public function assignedProducts($categoryId)
    {
        $category = $this->_initCategory($categoryId);

        $collection = $category->getProductCollection()->setOrder('position', 'asc');

        $result = array();

        foreach ($collection as $product) {
            $result[] = array(
                'product_id' => $product->getId(),
                'type'       => $product->getTypeId(),
                'set'        => $product->getAttributeSetId(),
                'sku'        => $product->getSku(),
                'position'   => $product->getPosition()
            );
        }

        return $result;
    }

    /**
     * Assign product to category
     *
     * @param int $categoryId
     * @param int $productId
     * @param int $position
     * @return boolean
     */
    public function assignProduct($categoryId, $productId, $position = null)
    {
        $category = $this->_initCategory($categoryId);
        $positions = $category->getProductsPosition();
        $productId = $this->_getProductId($productId);
        $positions[$productId] = $position;
        $category->setPostedProducts($positions);

        try {
            $category->save();
        } catch (Mage_Core_Exception $e) {
            $this->_fault('data_invalid', $e->getMessage());
        }

        return true;
    }


    /**
     * Update product assignment
     *
     * @param int $categoryId
     * @param int $productId
     * @param int $position
     * @return boolean
     */
    public function updateProduct($categoryId, $productId, $position = null)
    {
        $category = $this->_initCategory($categoryId);
        $positions = $category->getProductsPosition();
        $productId = $this->_getProductId($productId);
        if (!isset($positions[$productId])) {
            $this->_fault('product_not_assigned');
        }
        $positions[$productId] = $position;
        $category->setPostedProducts($positions);

        try {
            $category->save();
        } catch (Mage_Core_Exception $e) {
            $this->_fault('data_invalid', $e->getMessage());
        }

        return true;
    }

    /**
     * Remove product assignment from category
     *
     * @param int $categoryId
     * @param int $productId
     * @return boolean
     */
    public function removeProduct($categoryId, $productId)
    {
        $category = $this->_initCategory($categoryId);
        $positions = $category->getProductsPosition();
        $productId = $this->_getProductId($productId);
        if (!isset($positions[$productId])) {
            $this->_fault('product_not_assigned');
        }

        unset($positions[$productId]);
        $category->setPostedProducts($positions);

        try {
            $category->save();
        } catch (Mage_Core_Exception $e) {
            $this->_fault('data_invalid', $e->getMessage());
        }

        return true;
    }

} // Class Mage_Catalog_Model_Category_Api End