Club Drupal

<?php

/**

 * @file

 * FeedsConfigurable and helper functions.

 */

/**

 * Used when an object does not exist in the DB or code but should.

 */

class FeedsNotExistingException extends Exception {

}

/**

 * Base class for configurable classes.

 *

 * Captures configuration handling, form handling and distinguishes between

 * in-memory configuration and persistent configuration.

 *

 * Due to the magic method __get(), protected properties from this class and

 * from classes that extend this class will be publicly readable (but not

 * writeable).

 */

abstract class FeedsConfigurable {

  /**

   * Holds the actual configuration information.

   *

   * @var array

   */

  protected $config;

  /**

   * An unique identifier for the configuration.

   *

   * @var string

   */

  protected $id;

  /**

   * CTools export type of this object.

   *

   * Export type can be one of:

   * - FEEDS_EXPORT_NONE - the configurable only exists in memory.

   * - EXPORT_IN_DATABASE - the configurable is defined in the database.

   * - EXPORT_IN_CODE - the configurable is defined in code.

   * - EXPORT_IN_CODE | EXPORT_IN_DATABASE - the configurable is defined in

   *   code, but overridden in the database.

   *

   * @var int

   *

   * @todo Should live in FeedsImporter. Not all child classes

   * of FeedsConfigurable are exportable. Same goes for $disabled.

   */

  protected $export_type;

  /**

   * CTools export enabled status of this object.

   *

   * @var bool

   */

  protected $disabled;

  /**

   * Provides a statically cached instance of a FeedsConfigurable subclass.

   *

   * Don't use directly, use feeds_importer() or feeds_plugin() instead.

   *

   * @param string $class

   *   The name of a subclass of FeedsConfigurable.

   * @param string $id

   *   The ID of this configuration object.

   *

   * @return FeedsConfigurable

   *   An instance of this class.

   *

   * @throws InvalidArgumentException

   *   When an empty configuration identifier is passed.

   *

   * @see feeds_importer()

   * @see feeds_plugin()

   */

  public static function instance($class, $id) {

    // @todo Verify that $class is an existing subclass of FeedsConfigurable.

    if (!strlen($id)) {

      throw new InvalidArgumentException(t('Empty configuration identifier.'));

    }

    $instances = &drupal_static(__METHOD__, array());

    if (!isset($instances[$class][$id])) {

      $instances[$class][$id] = new $class($id);

    }

    return $instances[$class][$id];

  }

  /**

   * Constructor, set id and load default configuration.

   *

   * @param string $id

   *   The ID of this configuration object.

   */

  protected function __construct($id) {

    // Set this object's id.

    $this->id = $id;

    // Per default we assume that a Feeds object is not saved to

    // database nor is it exported to code.

    $this->export_type = FEEDS_EXPORT_NONE;

    // Make sure configuration is populated.

    $this->config = $this->configDefaults();

    $this->disabled = FALSE;

  }

  /**

   * Override magic method __isset(). This is needed due to overriding __get().

   */

  public function __isset($name) {

    return isset($this->$name) ? TRUE : FALSE;

  }

  /**

   * Determine whether this object is persistent.

   *

   * @return bool

   *   True if the object is persistent.

   *   False otherwise.

   */

  public function doesExist() {

    return ($this->export_type == FEEDS_EXPORT_NONE) ? FALSE : TRUE;

  }

  /**

   * Determine whether this object is enabled.

   *

   * @return bool

   *   True if the object is enabled.

   *   False otherwise.

   */

  public function isEnabled() {

    return $this->disabled ? FALSE : TRUE;

  }

  /**

   * Determines whether this object is persistent and enabled.

   *

   * This means that it exists either in code or in the database and it is

   * enabled.

   *

   * @return $this

   *

   * @throws FeedsNotExistingException

   *   When the object is not persistent or is not enabled.

   */

  public function existing() {

    if (!$this->doesExist()) {

      throw new FeedsNotExistingException(t('Object is not persistent.'));

    }

    if (!$this->isEnabled()) {

      throw new FeedsNotExistingException(t('Object is disabled.'));

    }

    return $this;

  }

  /**

   * Saves a configuration.

   *

   * Concrete extending classes must implement a save operation.

   */

  abstract public function save();

  /**

   * Copy a configuration.

   *

   * @param FeedsConfigurable $configurable

   *   The FeedsConfigurable instance to take the configuration from.

   */

  public function copy(FeedsConfigurable $configurable) {

    $this->setConfig($configurable->config);

  }

  /**

   * Set configuration.

   *

   * @param array $config

   *   Array containing configuration information. Config array will be filtered

   *   by the keys returned by configDefaults() and populated with default

   *   values that are not included in $config.

   */

  public function setConfig($config) {

    $defaults = $this->configDefaults();

    $this->config = array_intersect_key($config, $defaults) + $defaults;

  }

  /**

   * Similar to setConfig but adds to existing configuration.

   *

   * @param array $config

   *   Array containing configuration information. Will be filtered by the keys

   *   returned by configDefaults().

   */

  public function addConfig($config) {

    $this->config = is_array($this->config) ? array_merge($this->config, $config) : $config;

    $default_keys = $this->configDefaults();

    $this->config = array_intersect_key($this->config, $default_keys);

  }

  /**

   * Overrides magic method __get().

   *

   * - Makes sure that external reads of FeedsConfigurable::config go through

   *   ::getConfig();

   * - Makes private and protected properties from this class and protected

   *   properties from child classes publicly readable.

   * - Prevents warnings when accessing non-existent properties.

   */

  public function __get($name) {

    if ($name == 'config') {

      return $this->getConfig();

    }

    return isset($this->$name) ? $this->$name : NULL;

  }

  /**

   * Implements getConfig().

   *

   * Returns configuration array, ensure that all default values are present.

   *

   * @return array

   *   The configuration for this object.

   */

  public function getConfig() {

    $defaults = $this->configDefaults();

    return $this->config + $defaults;

  }

  /**

   * Return default configuration.

   *

   * @todo rename to getConfigDefaults().

   *

   * @return array

   *   Array where keys are the variable names of the configuration elements and

   *   values are their default values.

   */

  public function configDefaults() {

    return array() + module_invoke_all('feeds_config_defaults', $this);

  }

  /**

   * Validates the configuration.

   *

   * @return array

   *   A list of errors.

   */

  public function validateConfig() {

    return array();

  }

  /**

   * Returns whether or not the configurable has a config form.

   *

   * @return bool

   *   True if the configurable has a config form, and false if not.

   */

  public function hasConfigForm() {

    $form_state = array();

    return (bool) $this->configForm($form_state);

  }

  /**

   * Returns configuration form for this object.

   *

   * The keys of the configuration form must match the keys of the array

   * returned by configDefaults().

   *

   * @param array $form_state

   *   The current state of the form.

   *

   * @return array

   *   FormAPI style form definition.

   */

  public function configForm(&$form_state) {

    return array();

  }

  /**

   * Validation handler for configForm().

   *

   * Set errors with form_set_error().

   *

   * @param array $values

   *   An array that contains the values entered by the user through configForm.

   */

  public function configFormValidate(&$values) {

  }

  /**

   * Submission handler for configForm().

   *

   * @param array $values

   *   An array that contains the values entered by the user through configForm.

   */

  public function configFormSubmit(&$values) {

    $this->addConfig($values);

    $this->save();

    drupal_set_message(t('Your changes have been saved.'));

    feeds_cache_clear(FALSE);

  }

  /**

   * Returns an array of required modules.

   *

   * @return array

   *   The modules that this configurable requires.

   */

  public function dependencies() {

    return array();

  }

}

/**

 * FeedsConfigurable config form wrapper.

 *

 * Used to render the configuration form of a FeedsConfigurable object.

 *

 * @param FeedsConfigurable $configurable

 *   The FeedsConfigurable instance for which a configuration form must be

 *   rendered.

 * @param string $form_method

 *   The form method that should be rendered.

 *

 * @return array|null

 *   Config form array if available. NULL otherwise.

 */

function feeds_get_form(FeedsConfigurable $configurable, $form_method) {

  if (method_exists($configurable, $form_method)) {

    return drupal_get_form(get_class($configurable) . '_feeds_form', $configurable, $form_method);

  }

}

/**

 * Form constructor for a Feeds configuration form.

 *

 * Don't call directly, but use

 * feeds_get_form($configurable, 'method') instead.

 *

 * @param array $form

 *   The form.

 * @param array $form_state

 *   The current state of the form.

 * @param FeedsConfigurable $configurable

 *   The object to perform the save() operation on.

 * @param string $form_method

 *   The $form_method that should be rendered.

 *

 * @return array

 *   Form array.

 */

function feeds_form(array $form, array &$form_state, FeedsConfigurable $configurable, $form_method) {

  $form = $configurable->$form_method($form_state);

  $form['#configurable'] = $configurable;

  $form['#feeds_form_method'] = $form_method;

  $form['#validate'] = array('feeds_form_validate');

  $form['#submit'] = array('feeds_form_submit');

  $form['submit'] = array(

    '#type' => 'submit',

    '#value' => t('Save'),

    '#weight' => 100,

  );

  return $form;

}

/**

 * Form validation handler for feeds_form().

 *

 * @see feeds_form()

 */

function feeds_form_validate($form, &$form_state) {

  _feeds_form_helper($form, $form_state, 'Validate');

}

/**

 * Submit handler for feeds_form().

 *

 * @see feeds_form()

 */

function feeds_form_submit($form, &$form_state) {

  _feeds_form_helper($form, $form_state, 'Submit');

}

/**

 * Helper for Feeds validate and submit callbacks.

 *

 * @param array $form

 *   The form.

 * @param array $form_state

 *   The current state of the form.

 * @param string $action

 *   The action to perform on the form, for example:

 *   - Validate;

 *   - Submit.

 *

 * @todo This is all terrible. Remove.

 */

function _feeds_form_helper(array $form, array &$form_state, $action) {

  $method = $form['#feeds_form_method'] . $action;

  $class = get_class($form['#configurable']);

  $id = $form['#configurable']->id;

  // Re-initialize the configurable object. Using feeds_importer() and

  // feeds_plugin() will ensure that we're using the same instance. We can't

  // reuse the previous form instance because feeds_importer() is used to save.

  // This will re-initialize all of the plugins anyway, causing some tricky

  // saving issues in certain cases.

  // See http://drupal.org/node/1672880.

  if ($class == variable_get('feeds_importer_class', 'FeedsImporter')) {

    $form['#configurable'] = feeds_importer($id);

  }

  else {

    $importer = feeds_importer($id);

    $plugin_key = $importer->config[$form['#configurable']->pluginType()]['plugin_key'];

    $form['#configurable'] = feeds_plugin($plugin_key, $id);

  }

  if (method_exists($form['#configurable'], $method)) {

    $form['#configurable']->$method($form_state['values']);

  }

}