<?php

/**
 * @author   Neuman Vong neuman@twilio.com
 * @license  http://creativecommons.org/licenses/MIT/ MIT
 * @link     http://pear.php.net/package/Services_Twilio
 */

/**
 * Abstraction of a list resource from the Twilio API.
 *
 * The list resource implements the `IteratorAggregate
 * <http://php.net/manual/en/class.iteratoraggregate.php>`_ and the `Countable
 * <http://php.net/manual/en/class.countable.php>`_ interfaces.
 *
 */
abstract class Services_Twilio_ListResource extends Services_Twilio_Resource
    implements IteratorAggregate, Countable
{

    public function __construct($client, $uri) {
        $name = $this->getResourceName(true);
        /*
         * By default trim the 's' from the end of the list name to get the
         * instance name (ex Accounts -> Account). This behavior can be
         * overridden by child classes if the rule doesn't work.
         */
        if (!isset($this->instance_name)) {
            $this->instance_name = "Services_Twilio_Rest_" . rtrim($name, 's');
        }

        parent::__construct($client, $uri);
    }

    /**
     * Gets a resource from this list.
     *
     * :param string $sid: The resource SID
     * :return: The resource
     * :rtype: :php:class:`InstanceResource <Services_Twilio_InstanceResource>`
     */
    public function get($sid) {
        $instance = new $this->instance_name(
            $this->client, $this->uri . "/$sid"
        );
        // XXX check if this is actually a sid in all cases.
        $instance->sid = $sid;
        return $instance;
    }

    /**
     * Construct an :php:class:`InstanceResource
     * <Services_Twilio_InstanceResource>` with the specified params.
     *
     * :param array $params: usually a JSON HTTP response from the API
     * :return: An instance with properties
     *      initialized to the values in the params array.
     * :rtype: :php:class:`InstanceResource <Services_Twilio_InstanceResource>`
     */
    public function getObjectFromJson($params, $idParam = "sid")
    {
        if (isset($params->{$idParam})) {
            $uri = $this->uri . "/" . $params->{$idParam};
        } else {
            $uri = $this->uri;
        }
        return new $this->instance_name($this->client, $uri, $params);
    }

    /**
     * Deletes a resource from this list.
     *
     * :param string $sid: The resource SID
     * :rtype: null
     */
    public function delete($sid, $params = array())
    {
        $this->client->deleteData($this->uri . '/' . $sid, $params);
    }

    /**
     * Create a resource on the list and then return its representation as an
     * InstanceResource.
     *
     * :param array $params: The parameters with which to create the resource
     *
     * :return: The created resource
     * :rtype: :php:class:`InstanceResource <Services_Twilio_InstanceResource>`
     */
    protected function _create($params)
    {
        $params = $this->client->createData($this->uri, $params);
        /* Some methods like verified caller ID don't return sids. */
        if (isset($params->sid)) {
            $resource_uri = $this->uri . '/' . $params->sid;
        } else {
            $resource_uri = $this->uri;
        }
        return new $this->instance_name($this->client, $resource_uri, $params);
    }

    /**
     * Returns a page of :php:class:`InstanceResources
     * <Services_Twilio_InstanceResource>` from this list.
     *
     * :param int    $page: The start page
     * :param int    $size: Number of items per page
     * :param array  $filters: Optional filters
     * :param string $deep_paging_uri: if provided, the $page and $size
     *      parameters will be ignored and this URI will be requested directly.
     *
     * :return: A page of resources
     * :rtype: :php:class:`Services_Twilio_Page`
     */
    public function getPage(
        $page = 0, $size = 50, $filters = array(), $deep_paging_uri = null
    ) {
        $list_name = $this->getResourceName();
        if ($deep_paging_uri !== null) {
            $page = $this->client->retrieveData($deep_paging_uri, array(), true);
        } else {
            $page = $this->client->retrieveData($this->uri, array(
                'Page' => $page,
                'PageSize' => $size,
            ) + $filters);
        }

        /* create a new PHP object for each json obj in the api response. */
        $page->$list_name = array_map(
            array($this, 'getObjectFromJson'),
            $page->$list_name
        );
        if (isset($page->next_page_uri)) {
            $next_page_uri = $page->next_page_uri;
        } else {
            $next_page_uri = null;
        }
        return new Services_Twilio_Page($page, $list_name, $next_page_uri);
    }

    /**
     * Get the total number of instances for this list.
     *
     * This will make one HTTP request to retrieve the total, every time this
     * method is called.
     *
     * If the total is not set, or an Exception was thrown, returns 0
     *
     * :return: The total number of instance members
     * :rtype: integer
     */
    public function count() {
        try {
            $page = $this->getPage(0, 1);
            return $page ? (int)$page->total : 0;
        } catch (Exception $e) {
            return 0;
        }
    }


    /**
     * Returns an iterable list of
     * :php:class:`instance resources <Services_Twilio_InstanceResource>`.
     *
     * :param int   $page: The start page
     * :param int   $size: Number of items per page
     * :param array $filters: Optional filters.
     *      The filter array can accept full datetimes when StartTime or DateCreated
     *      are used. Inequalities should be within the key portion of the array and
     *      multiple filter parameters can be combined for more specific searches.
     *
     *      .. code-block:: php
     *
     *          array('DateCreated>' => '2011-07-05 08:00:00', 'DateCreated<' => '2011-08-01')
     *
     *      .. code-block:: php
     *
     *          array('StartTime<' => '2011-07-05 08:00:00')
     *
     * :return: An iterator
     * :rtype: :php:class:`Services_Twilio_AutoPagingIterator`
     */
    public function getIterator(
        $page = 0, $size = 50, $filters = array()
    ) {
        return new Services_Twilio_AutoPagingIterator(
            array($this, 'getPageGenerator'), $page, $size, $filters
        );
    }

    /**
     * Retrieve a new page of API results, and update iterator parameters. This
     * function is called by the paging iterator to retrieve a new page and
     * shouldn't be called directly.
     */
    public function getPageGenerator(
        $page, $size, $filters = array(), $deep_paging_uri = null
    ) {
        return $this->getPage($page, $size, $filters, $deep_paging_uri);
    }
}