<?php
// $Id: flickrapi.module,v 1.2.2.1 2010/11/23 03:30:45 taniwha Exp $

/**
 * Implementation of hook_menu().
 */
function flickrapi_menu() {
  $items = array();
  $items['admin/settings/flickrapi'] = array(
    'title' => 'Flickr API Settings',
    'description' => 'Configure Flickr API credentials.',
    'access arguments' => array('administer site configuration'),
    'type' => MENU_NORMAL_ITEM,
    'page callback' => 'drupal_get_form',
    'page arguments' => array('flickrapi_admin_settings')
  );
  return $items;
}

function flickrapi_admin_settings() {
  $form = array();
	
  $form['flickrapi_api_key'] = array(
    '#type' => 'textfield',
    '#title' => t('API Key'),
    '#required' => TRUE,
    '#default_value' => variable_get('flickrapi_api_key', ''),
    '#description' => t('API Key from Flickr'),
  );
  $form['flickrapi_api_secret'] = array(
    '#type' => 'textfield',
    '#title' => t('API Shared Secret'),
    '#required' => FALSE,
    '#default_value' => variable_get('flickrapi_api_secret', ''),
    '#description' => t("API key's secret from Flickr."),
  );
  $times = array(900, 1800, 2700, 3600, 7200, 10800, 14400, 18000, 21600, 43200, 86400);
  $ageoptions = drupal_map_assoc($times, 'format_interval');
  $form['flickrapi_cache_duration'] = array(
    '#type' => 'select',
    '#title' => t('Update interval'),
    '#options' => $ageoptions,
    '#default_value' => variable_get('flickrapi_cache_duration', 3600),
    '#description' => t("The refresh interval indicating how often you want to check cached Flickr API calls are up to date."),
  );

  $form['flickrcachepath'] = array(
    '#title' => t('Flickr Cache Path'),
    '#required' => TRUE,
    '#description' => t('Location on server file system where results of Flickr API calls can be cached.'),
    '#type' => 'textfield',
    '#default_value' => variable_get('flickrcachepath', '/tmp'),
  );
  
  $form['#validate'][] = 'flickrapi_admin_settings_validate';
  return system_settings_form($form);
}

function flickrapi_admin_settings_validate($form, &$form_state) {
  $key = trim($form_state['values']['flickrapi_api_key']);
  $sec = trim($form_state['values']['flickrapi_api_secret']);
	
  if ($key && (preg_match('/^[A-Fa-f\d]{32}$/', $key) != 1)) {
    form_set_error('flickrapi_api_key', t('This does not appear to be a Flickr API key.'));
  }
  if ($sec && (preg_match('/^[A-Fa-f\d]{16}$/', $sec) != 1)) {
    form_set_error('flickrapi_api_secret', t('This does not appear to be a Flickr API secret.'));
  }
}

/**
 * returns the phpFlickr object.
 * If we need to change anything, such as making the cache configuration,
 * then it'll all be done here.
 */
function flickrapi_phpFlickr() {
  module_load_include('php', 'flickrapi', 'phpFlickr/phpFlickr');
  
  $api_key = variable_get('flickrapi_api_key', '');
  if (!$api_key) {
    drupal_set_message(t("Flickr API key not set"), 'error');
    if (user_access('Administer global flickr api settings')) {
      drupal_set_message(t("Goto !link to configure the Flickr API settings", array('!link' => l('admin/settings/flickrapi', 'admin/settings/flickrapi'))));
    }
  }
  $flickr = new phpFlickr($api_key);
  $flickr->enableCache("fs", variable_get('flickrcachepath', '/tmp'));
  return $flickr;
}

/**
 * Tries to match an 'identifier' onto a flickr nsid
 *
 * This function will first see whether $identifier is allready
 * a nsid (format check only, no api call).  If it is not and the
 * identifier has the format of an email, an api call will be made to
 * check whether there is an nsid for that email.  If this is not the
 * case, the $identifier is treated as a username and an api call is
 * made to find the nsid for that username.
 *
 * If none of these succees, the result will be false
 *
 * @param $identifier
 *   identifier to find an nsid for
 *
 * @return
 *   valid nsid or false if none can be found
 */
function flickrapi_get_user_nsid($identifier) {
  if (flickrapi_is_nsid($identifier)) {
    //identifier is an NSID
    return $identifier;
  }
  $f = flickrapi_phpFlickr();
  if (valid_email_address($identifier) && ($user = $f->people_findByEmail($identifier))) {
    return $user['nsid'];
  }
  if ($user = $f->people_findByUsername($identifier)) {
    return $user['nsid'];
  }
  
  return FALSE;
}

function flickrapi_is_nsid($id) {
  return preg_match('/^\d+@N\d+$/', $id);
}