<?php

/**
 * @file
 * Plugin to provide a OpenStreetMap Nominatim geocoder.
 */

$plugin = array(
  'title' => t('OpenStreetMap Nominatim'),
  'description' => t('Geocodes via OpenStreetMap Nominatim'),
  'callback' => 'geocoder_openstreetmap_nominatim',
  'field_types' => array(
    'text',
    'text_long',
    'addressfield',
    'location',
    'text_with_summary',
    'computed',
    'taxonomy_term_reference',
  ),
  'field_callback' => 'geocoder_openstreetmap_nominatim_field',
  'terms_of_service' => 'http://www.openstreetmap.org/copyright',
);

/**
 * Process Markup.
 */
function geocoder_openstreetmap_nominatim($address, $options = array()) {
  $api_url = 'http://nominatim.openstreetmap.org/';

  $params = array(
    'q' => str_replace(' ', '+', $address),
    'format' => 'json',
    'addressdetails' => 0,
    'limit' => 1,
    'osm_type' => 'N',
  );
  $request = drupal_http_request($api_url . '?' . urldecode(drupal_http_build_query($params)));
  $data = json_decode($request->data);

  return _geocoder_openstreetmap_nominatim_geometry($data);
}

/**
 * Plugin callback.
 */
function geocoder_openstreetmap_nominatim_field($field, $field_item) {
  if ($field['type'] === 'text' || $field['type'] === 'text_long' || $field['type'] === 'text_with_summary' || $field['type'] === 'computed') {
    return geocoder_openstreetmap_nominatim($field_item['value']);
  }
  if ($field['type'] === 'addressfield') {
    $address = geocoder_widget_parse_addressfield($field_item);

    return geocoder_openstreetmap_nominatim($address);
  }
  if ($field['type'] === 'location') {
    $address = geocoder_widget_parse_locationfield($field_item);

    return geocoder_openstreetmap_nominatim($address);
  }
  if ($field['type'] === 'taxonomy_term_reference') {
    $term = taxonomy_term_load($field_item['tid']);

    return geocoder_openstreetmap_nominatim($term->name);
  }
}

/**
 * Plugin callback.
 */
function _geocoder_openstreetmap_nominatim_geometry(&$data) {
  if (!isset($data[0]->lon)) {
    return NULL;
  }
  geophp_load();

  return new Point($data[0]->lon, $data[0]->lat);
}
