<?php

/**
 * @file
 * This file will define the resources for dealing directly with nodes
 */

function _node_resource_definition() {
  $node_resource = array(
    'node' => array(
      'retrieve' => array(
        'file' => array('type' => 'inc', 'module' => 'services', 'name' => 'resources/node_resource'),
        'callback' => '_node_resource_retrieve',
        'args' => array(
          array(
            'name' => 'nid',
            'optional' => FALSE,
            'source' => array('path' => 0),
            'type' => 'int',
            'description' => 'The nid of the node to get',
          ),
        ),
        'access callback' => '_node_resource_access',
        'access arguments' => array('view'),
        'access arguments append' => TRUE,
      ),
      'create' => array(
        'file' => array('type' => 'inc', 'module' => 'services', 'name' => 'resources/node_resource'),
        'callback' => '_node_resource_create',
        'args' => array(
          array(
            'name' => 'node',
            'optional' => FALSE,
            'source' => 'data',
            'description' => 'The node data to create',
            'type' => 'array',
          ),
        ),
        'access callback' => '_node_resource_access',
        'access arguments' => array('create'),
        'access arguments append' => TRUE,
      ),
      'update' => array(
        'file' => array('type' => 'inc', 'module' => 'services', 'name' => 'resources/node_resource'),
        'callback' => '_node_resource_update',
        'args' => array(
          array(
            'name' => 'nid',
            'optional' => FALSE,
            'source' => array('path' => 0),
            'type' => 'int',
            'description' => 'The nid of the node to get',
          ),
          array(
            'name' => 'node',
            'optional' => FALSE,
            'source' => 'data',
            'description' => 'The node data to update',
            'type' => 'struct',
          ),
        ),
        'access callback' => '_node_resource_access',
        'access arguments' => array('update'),
        'access arguments append' => TRUE,
      ),
      'delete' => array(
        'file' => array('type' => 'inc', 'module' => 'services', 'name' => 'resources/node_resource'),
        'callback' => '_node_resource_delete',
        'args' => array(
          array(
            'name' => 'nid',
            'optional' => FALSE,
            'type' => 'int',
            'source' => array('path' => 0),
          ),
        ),
        'access callback' => '_node_resource_access',
        'access arguments' => array('delete'),
        'access arguments append' => TRUE,
      ),
      'index' => array(
        'file' => array('type' => 'inc', 'module' => 'services', 'name' => 'resources/node_resource'),
        'callback' => '_node_resource_index',
        'args' => array(
          array(
            'name' => 'page',
            'optional' => TRUE,
            'type' => 'int',
            'description' => 'The zero-based index of the page to get, defaults to 0.',
            'default value' => 0,
            'source' => array('param' => 'page'),
          ),
          array(
            'name' => 'fields',
            'optional' => TRUE,
            'type' => 'string',
            'description' => 'The fields to get.',
            'default value' => '*',
            'source' => array('param' => 'fields'),
          ),
          array(
            'name' => 'parameters',
            'optional' => TRUE,
            'type' => 'array',
            'description' => 'Parameters array',
            'default value' => array(),
            'source' => array('param' => 'parameters'),
          ),
          array(
            'name' => 'pagesize',
            'optional' => TRUE,
            'type' => 'init',
            'description' => 'Number of records to get per page.',
            'default value' => variable_get('services_node_index_page_size', 20),
            'source' => array('param' => 'pagesize'),
          ),
        ),
        'access arguments' => array('access content'),
      ),
      'relationships' => array(
        'files' => array(
          'file' => array('type' => 'inc', 'module' => 'services', 'name' => 'resources/node_resource'),
          'help'   => t('This method returns files associated with a node.'),
          'access callback' => '_node_resource_access',
          'access arguments' => array('view'),
          'access arguments append' => TRUE,
          'callback' => '_node_resource_load_node_files',
          'args'     => array(
            array(
              'name' => 'nid',
              'optional' => FALSE,
              'source' => array('path' => 0),
              'type' => 'int',
              'description' => 'The nid of the node whose files we are getting',
            ),
            array(
              'name' => 'file_contents',
              'type' => 'int',
              'description'  => t('To return file contents or not.'),
              'source' => array('path' => 2),
              'optional' => TRUE,
              'default value' => FALSE,
            ),
          ),
        ),
      ),
    ),
  );
  if (module_exists('comment')) {
    $comments = array(
      'file'                    => array('type' => 'inc', 'module' => 'services', 'name' => 'resources/node_resource'),
      'help'                    => t('This method returns comments from a given node.'),
      'access callback'         => 'user_access',
      'access arguments'        => array('access comments'),
      'access arguments append' => FALSE,
      'callback'                => '_node_resource_load_node_comments',
      'args'                    => array(
        array(
          'name'         => 'nid',
          'type'         => 'int',
          'description'  => t('The node id to load comments for.'),
          'source'       => array('path' => 0),
          'optional'     => FALSE,
        ),
        array(
          'name'         => 'count',
          'type'         => 'int',
          'description'  => t('Number of comments to load.'),
          'source'       => array('param' => 'count'),
          'optional'     => TRUE,
        ),
        array(
          'name'         => 'offset',
          'type'         => 'int',
          'description'  => t('If count is set to non-zero value, you can pass also non-zero value for start. For example to get comments from 5 to 15, pass count=10 and start=5.'),
          'source'       => array('param' => 'offset'),
          'optional'     => TRUE,
        ),
      ),
    );
    $node_resource['node']['relationships']['comments'] =  $comments;
  }
  return $node_resource;
}
/**
 * Returns the comments of a specified node.
 *
 * @param $nid
 *   Unique identifier for the node.
 * @param $count
 *   Number of comments to return.
 * @param $start
 *   Which comment to start with. if present, $start and $count are used together
 *   to create a LIMIT clause for selecting comments. This could be used to do paging.
 * @return
 *   An array of comment objects.
 */
function _node_resource_load_node_comments($nid, $count, $start) {
  $comments = array();
  $limit = ((int)$count > 0 ? ' LIMIT ' . (int)$start . ', ' . (int)$count . ' ' : '');

  $result = db_query("SELECT cid FROM {comments} WHERE nid = %d AND status = %d ORDER BY thread DESC" . $limit, $nid, COMMENT_PUBLISHED);
  while ($comment = db_fetch_array($result)) {
    $comments[] = _comment_load($comment['cid']);
  }

  return $comments;
}
/**
 * Returns the results of a node_load() for the specified node.
 *
 * This returned node may optionally take content_permissions settings into
 * account, based on a configuration setting.
 *
 * @param $nid
 *   NID of the node we want to return.
 * @return
 *   Node object or FALSE if not found.
 *
 * @see node_load()
 */
function _node_resource_retrieve($nid) {
  global $user;
  $node = node_load($nid);

  if ($node) {
    // Apply field level content permissions
    if (module_exists('content') && variable_get('services_use_content_permissions', TRUE)) {
      $fields = content_fields(NULL, $node->type);
      foreach ($fields as $field_name => $field_info) {
        if (isset($node->$field_name)) {
          $access = module_invoke_all('field_access', 'view', $field_info, $user, $node);
          if (in_array(FALSE, $access)) {
            unset($node->$field_name);
          }
        }
      }
    }
    $node->uri = services_resource_uri(array('node', $node->nid));
    return $node;
  }
  return services_error('Node nid '. $nid .' not found', 404);
}

/**
 * Creates a new node based on submitted values.
 *
 * Note that this function uses drupal_execute() to create new nodes,
 * which may require very specific formatting. The full implications of this
 * are beyond the scope of this comment block. The Googles are your friend.
 *
 * @param $node
 *   Array representing the attributes a node edit form would submit.
 * @return
 *   An associative array contained the new node's nid and, if applicable,
 *   the fully qualified URI to this resource.
 *
 * @see drupal_execute()
 */
function _node_resource_create($node) {
  // Adds backwards compatability with regression fixed in #1083242
  $node = _services_arg_value($node, 'node');

  if (!isset($node['name'])) {
    // Assign username to the node from $user created at auth step.
    global $user;
    $node['name'] = $user->name;
  }

  // Validate the node. If there is validation error Exception will be thrown
  // so code below won't be executed.
  _node_resource_validate_type($node);

  $node_type = $node['type'];

  // Load the required includes for drupal_execute
  module_load_include('inc', 'node', 'node.pages');
  $nid = NULL;
  if (module_exists('content') && variable_get('services_use_content_permissions', TRUE)) {
    $fields = content_fields(NULL, $node['type']);
    foreach ($fields as $field_name => $field_info) {
      if (isset($node[$field_name])) {
        $access = module_invoke_all('field_access', 'view', $field_info, $user, (object)$node);
        if (in_array(FALSE, $access)) {
          unset($node[$field_name]);
        }
      }
    }
  }
  // Setup form_state
  $form_state = array();
  $form_state['values'] = $node;
  $form_state['values']['op'] = variable_get('services_node_save_button_' . $node_type . '_resource_create', t('Save'));
  $ret = drupal_execute($node_type . '_node_form', $form_state, (object)$node);

  if ($errors = form_get_errors()) {
    return services_error(implode(" ", $errors), 406, array('form_errors' => $errors));
  }
  // Fetch $nid out of $form_state
  $nid = $form_state['nid'];
  // Only add the URI for servers that support it.
  $node = array('nid' => $nid);
  if ($uri = services_resource_uri(array('node', $nid))) {
    $node['uri'] = $uri;
  }
  return $node;
}

/*
 * Helper function to validate node type information.
 *
 * @param $node
 *   Array representing the attributes a node edit form would submit.
 */
function _node_resource_validate_type($node) {
  if (!isset($node['type'])) {
    return services_error(t('Missing node type'), 406);
  }
  // Wanted to return a graceful error instead of a blank nid, this should
  // allow for that.
  $types = node_get_types();
  $node_type = $node['type'];
  if (!isset($types[$node_type])) {
    return services_error(t('Node type @type does not exist.', array('@type' => $node_type)), 406);
  }
  $allowed_node_types = variable_get('services_allowed_create_content_types', $types);
  if (!isset($allowed_node_types[$node_type])) {
    return services_error(t("This node type @type can't be processed via services", array('@type' => $node_type)), 406);
  }
}

/**
 * Updates a new node based on submitted values.
 *
 * Note that this function uses drupal_execute() to create new nodes,
 * which may require very specific formatting. The full implications of this
 * are beyond the scope of this comment block. The Googles are your friend.
 *
 * @param $nid
 *   Node ID of the node we're editing.
 * @param $node
 *   Array representing the attributes a node edit form would submit.
 * @return
 *   The node's nid.
 *
 * @see drupal_execute()
 */
function _node_resource_update($nid, $node) {
  // Adds backwards compatability with regression fixed in #1083242
  $node = _services_arg_value($node, 'node');

  // Validate the node. If there is validation error Exception will be thrown
  // so code below won't be executed.
  _node_resource_validate_type($node);

  $node['nid'] = $nid;

  $old_node = node_load($nid);
  if ($old_node->nid) {
    // Node types cannot be changed once they are created.
    if (isset($node['type']) && $node['type'] != $old_node->type) {
      return services_error(t('Node type cannot be changed'), 406);
    }

    // Load the required includes for drupal_execute
    module_load_include('inc', 'node', 'node.pages');

    $node_type = $node['type'];

    // Setup form_state.
    $form_state = array();
    $form_state['values'] = $node;
    $form_state['values']['op'] = variable_get('services_node_save_button_' . $node_type . '_resource_update', t('Save'));
    $form_state['node'] = (array)$old_node;

    drupal_execute($node_type . '_node_form', $form_state, $old_node);

    if ($errors = form_get_errors()) {
      return services_error(implode(" ", $errors), 406, array('form_errors' => $errors));
    }
  }
  else {
    return services_error(t('Node not found'), 404);
  }

  $node = array('nid' => $nid);
  if ($uri = services_resource_uri(array('node', $nid))) {
    $node['uri'] = $uri;
  }
  return $node;
}

/**
 * Delete a node given its nid.
 *
 * @param $nid
 *   Node ID of the node we're deleting.
 * @return
 *   The node's nid.
 */
function _node_resource_delete($nid) {
  node_delete($nid);
  return TRUE;
}

/**
 * Return an array of optionally paged nids baed on a set of criteria.
 *
 * An example request might look like
 *
 * http://domain/endpoint/node?fields=nid,vid&parameters[nid]=7&parameters[uid]=1
 *
 * This would return an array of objects with only nid and vid defined, where
 * nid = 7 and uid = 1.
 *
 * @param $page
 *   Page number of results to return (in pages of 20).
 * @param $fields
 *   The fields you want returned.
 *   An array containing fields and values used to build a sql WHERE clause
 *   indicating items to retrieve.
 * @param $page_size
 *   Integer number of items to be returned.
 *   An array of node objects.
 *
 * @todo
 *   Evaluate the functionality here in general. Particularly around
 *     - Do we need fields at all? Should this just return full nodes?
 *     - Is there an easier syntax we can define which can make the urls
 *       for index requests more straightforward?
 */
function _node_resource_index($page, $fields, $parameters, $page_size) {
  // Limit to published nodes if user doesn't have 'administer nodes'
  // permissions.
  if (!user_access('administer nodes')) {
    $parameters['status'] = 1;
  }
  $query = services_resource_build_index_query('node', 'n.sticky DESC, n.created DESC', $page, $fields, $parameters, 'n', 'nid', $page_size, 'node');
  // Put together array of matching nodes to return.
  $results = array();
  while ($node = db_fetch_object($query)) {
    $results[] = $node;
  }

  return services_resource_build_index_list($results, 'node', 'nid');
}

/**
 * Generates an array of base64 encoded files attached to a node
 *
 * @param $nid
 *   Number. Node ID
 * @param $include_file_contents
 *   Bool Whether or not to include the base64_encoded version of the file.
 * @return
 *   Array. A list of all files from the given node
 */
function _node_resource_load_node_files($nid, $include_file_contents) {
  module_load_include('inc', 'services', 'resources/file_resource');
  $node = node_load($nid);
  if (!isset($node->files)) {
    return services_error(t('There are no files on given node.'));
  }

  $return = array();
  foreach ($node->files as $file) {
    // Do not return files that are not listed.
    if (!$file->list) {
      continue;
    }
    $return[$file->fid] = _file_resource_retrieve($file->fid, $include_file_contents);

  }
  return $return;
}

/**
 * Determine whether the current user can access a node resource.
 *
 * @param $op
 *   One of view, update, create, delete per node_access().
 * @param $args
 *   Resource arguments passed through from the original request.
 * @return bool
 *
 * @see node_access()
 */
function _node_resource_access($op = 'view', $args = array()) {
  // Adds backwards compatability with regression fixed in #1083242
  $args[0] = _services_access_value($args[0], 'node');
  // Make sure we have an object or this all fails, some servers can
  // mess up the types.
  if (is_array($args[0])) {
    $args[0] = (object) $args[0];
  }
  elseif (!is_array($args[0]) && !is_object($args[0])) {  //This is to determine if it is just a string
    $args[0] = (object)array('nid' => $args[0]);
  }

  if ($op != 'create' && !empty($args)) {
    $node = node_load($args[0]->nid);
  }
  elseif ($op == 'create') {
    $node = $args[0]->type;
    return node_access($op, $node);
  }
  if (isset($node->nid) && $node->nid) {
    return node_access($op, $node);
  }
  else {
    return services_error('Node id: '. $args[0]->nid .' could not be found', 404);
  }
}