<?php
// $Id: exif.module,v 1.9.2.18 2010/07/23 17:47:46 rapsli Exp $:

/**
 * @file implementing the drupal api
 */
/**
 * @author: Raphael Schär - www.rapsli.ch
 */

function exif_menu() {
  $items['admin/settings/exif'] = array(
    'title' => 'Exif',
    'page callback' => 'exif_admin_settings',
    'access arguments' => array('administer site configuration'),
    'description' => t('Display available fields'),
    'access callback' => 'user_access',
    'file' => 'exif.admin.inc',
    'type' => MENU_NORMAL_ITEM,
  );
  $items['admin/settings/exif/general'] = array(
    'title' => 'Exif',
    'page callback' => 'exif_admin_settings',
    'access arguments' => array('administer site configuration'),
    'description' => t('Display available fields'),
    'access callback' => 'user_access',
    'file' => 'exif.admin.inc',
    'type' => MENU_DEFAULT_LOCAL_TASK,
  );
  $items['admin/settings/exif/config'] = array(
    'title' => 'Config',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('exif_admin_settings_form'),
    'access arguments' => array('administer site configuration'),
    'description' => t('Some Settings'),
    'access callback' => 'user_access',
    'file' => 'exif.admin.inc',
    'type' => MENU_LOCAL_TASK,
  );
  return $items;
}

/**
 * implementation of hook_nodeapi
 */
function exif_nodeapi(&$node, $op, $teaser = NULL, $page = NULL) {

  if ($teaser) {
    return;
  }

  switch ($op) {

    case 'update':
      //we are only going to update if we have said so
      if (!variable_get('exif_update', TRUE)) {
        break;
      }
    case 'insert':
      if (! _exif_check_for_exif_data($node->type)) {
        return;
      }
      $info = content_types($node->type);
      $fields = $info['fields'];
      $exif = _exif_get_class();

      //get all the fields that will be filled with exif data
      $ar_exif_fields = $exif->getExifFields($fields);

      //get the path to the image
      $image_path = _exif_get_image_path($fields, $node);

      $fid = db_result(db_query("SELECT fid FROM {files} WHERE filepath = '%s'", $image_path));
      $file = file_create_path($image_path);

      $data1 = _exif_reformat($exif->readExifTags($file, $ar_exif_fields));
      $data2 = $exif->readIPTCTags($file, $ar_exif_fields);

      if (class_exists('SXMPFiles')) {
        $data3 = $exif->readXMPTags($file, $ar_exif_fields);
        $data = array_merge($data1, $data2, $data3);
      }
      else {
        $data = array_merge($data1, $data2);
      }

      // Loop through every exif enabled field and set its value to the
      // corresponding exif value. If no exif value was found, set the field
      // value to NULL, to avoid strange behaviour in other field modules
      // (date).
      foreach ($ar_exif_fields as $ar_exif_field) {
        $exif_name = $ar_exif_field['section'] .'_'. $ar_exif_field['tag'];
        $exif_value = isset($data[$exif_name]) ? $data[$exif_name] : NULL;

        $field_name = 'field_'. $exif_name;
        if (! $exif_value) {
          if (variable_get('exif_empty_values', TRUE)) {
            $node->{$field_name}[0]['value'] = NULL;
          }
          continue;
        }
        $field = $fields[$field_name];

        // Setup the field value array for delta = 0.
        switch ($exif_name) {
          case 'exif_datetimeoriginal':
          case 'exif_datetimedigitized':
          case 'ifd0_datetime':
            $first_delta = _exif_date_handler($field, $exif_value);
            break;
          default:
            $first_delta = array('value' => $data[$exif_name]);
            break;
        }
        $node->{$field_name}[0] = $first_delta;
      }
      break;
  }
}

/**
 * Date API hook.
 *
 * Make exif a date format in Date API. This makes it possible to alter the
 * format exif dates is parsed as.
 */
function exif_date_format_types() {
  return array('exif' => 'EXIF');
}

/**
 * Date API hook.
 *
 * Make the EXIF date format default for the 'exif' date type.
 */
function exif_date_formats() {
  return array(
  array(
      'type' => 'exif',
      'format' => 'Y:m:d H:i:s',
  ),
  );
}

/**
 * Helper function to handle all date values from exif header. This is
 * designed for the date_api and date modules, but is compatible if these
 * aren't enabled.
 *
 * @param array $field
 *   The field definition for the matcing exif date
 * @param string $exif_date
 *   The date extracted from exif header.
 * @return array
 *   The field value array for delta = 0
 */
function _exif_date_handler($field, $exif_date) {
  if (! module_exists('date_api')) {
    // Don't bother doing anything if the webmaster doesn't ...
    return array('value' => $exif_date);
  }

  require_once drupal_get_path('module', 'date_api') .'/date_api_elements.inc';
  $date_datetime = date_convert_from_custom($exif_date, variable_get('date_format_exif', 'Y:m:d H:i:s'));
  if (! in_array($field['type'], array('date', 'datetime', 'datestamp'))) {
    // Field is not a date field type, so we return a ISO-8601 representation
    return array('value' => date_convert($date_datetime, DATE_DATETIME, DATE_ISO));
  }

  // Exif doesn't handles timezones, so we assume the exif date is in the
  // timezone configured for this date field.  This means the exif date needs
  // to be converted to UTC before it's stored.
  $timezone = date_get_timezone($field['tz_handling']);
  $date = date_make_date($date_datetime, $timezone, DATE_DATETIME, $field['granularity']);

  // Store date offset before converting to UTC as this is lost when setting
  // timezone to 'UTC'.
  $offset = date_offset_get($date);
  date_timezone_set($date, timezone_open('UTC'));

  // Finally, convert the date object in UTC to a date according to the field
  // type: DATE_ISO, DATE_DATETIME or DATE_UNIX.
  $date_field = date_convert($date, DATE_OBJECT, $field['type']);
  return array(
    'value' => $date_field,
    'value2' => $date_field,
    'timezone' => $timezone,
    'offset' => $offset,
    'offset2' => $offset,
  );
}

/**
 * Let's check if this node type contains an image field.
 *
 * @param $fields fields from this content type
 * @return boolean
 */
function _exif_check_for_exif_data($node_type) {

  $new_types = array();
  //fill up array with checked nodetypes
  foreach (variable_get('exif_nodetypes', array()) as $type) {
    if ($type != "0" ) {
      $new_types[] = $type;
    }
  }
  if (in_array($node_type, $new_types)) {
    return TRUE;
  }
  return FALSE;
}

/**
 * From a given node we are going to get the imagepath of the image. if it's an image node
 * it's just going to be images[IMAGE_ORIGINAL]. If it's an imagefield node, we have to go
 * through the fields and look if there is an imagefield and then return the path
 *
 * @param $fields
 * @param $node
 * @return unknown_type
 */
function _exif_get_image_path($fields, &$node) {
  if ($node->type == 'image') {
    return $node->images[IMAGE_ORIGINAL];
  }

  foreach ($fields as $field) {
    if ($field['type'] == 'filefield') {
      $tmp = $node->$field['field_name'];
      return $tmp[0]['filepath'];
    }
  }
  return NULL;
}


/**
 * Helper function to reformat fields where required.
 *
 * Some values (lat/lon) break down into structures, not strings.
 */
function _exif_reformat($data) {
  $date_array = array('datetimeoriginal', 'datetime', 'datetimedigitized');

  // Make the key lowercase as CCK field names must be
  $data = array_change_key_case($data, CASE_LOWER);

  foreach ($data as $key => &$value) {
    if (is_array($value))  {
      $value = array_change_key_case($value, CASE_LOWER);
    }

    // Check for individual keys
    switch ($key) {
      case 'gpslatitude':
        $value = _exif_DMS2D($value, $data['gpslatituderef']);
        break;

      case 'gpslongitude':
        $value = _exif_DMS2D($value, $data['gpslongituderef']);
        break;

      case 'gps_gpslatitude':
        $value = _exif_DMS2D($value, $data['gps_gpslatituderef']);
        break;

      case 'gps_gpslongitude':
        $value = _exif_DMS2D($value, $data['gps_gpslongituderef']);
        break;
         
    }
  }
  return $data;
}

/**
 * Helper function to change GPS co-ords into decimals.
 */
function _exif_DMS2D($value, $ref) {
  $parts = split('/', $value[0]);
  $dec = (float) ((float) $parts[0] /  (float) $parts[1]);

  $parts = split('/', $value[1]);
  $dec += (float) (((float) $parts[0] /  (float) $parts[1]) / 60);

  $parts = split('/', $value[2]);
  $dec += (float) (((float) $parts[0] /  (float) $parts[1]) / 3600);

  if ($ref == 'S' || $ref == 'W') $dec *= -1;
  return $dec;
}

/**
 * Helper function to get the exif class
 * @return Exif
 */
function _exif_get_class() {
  include_once drupal_get_path('module', 'exif') .'/exif.class.php';
  $exif = Exif::getInstance();
  return $exif;
}

/**
 * Implementation of hook_hoken_list
 * @param array $type
 */
function fast_gallery_token_list($type = 'node') {
  if ($type == 'node') {
    $exif = _exif_get_class();
    $ar_iptc = $exif->getHumanReadableIPTCkey();
    foreach ($ar_iptc as $iptc) {
      $tokens['iptc']['iptc_' . $iptc] = 'IPTC Field: ' . $iptc;
    }
    return $tokens;
  }
}

/**
 * implementation of hook_token_values
 * @param unknown_type $type
 * @param unknown_type $object
 * @param unknown_type $options
 */
function fast_gallery_token_values($type, $object = NULL, $options = array()) {
  if ($type == 'node') {
    $node = $object;
    $exif = _exif_get_class();
    $ar_iptc = $exif->getHumanReadableIPTCkey();

    $info = content_types($node->type);
    $fields = $info['fields'];
    //get the path to the image
    $image_path = _exif_get_image_path($fields, $node);
    
    //dsm("start reading");
    $iptc_values = $exif->readIPTCTags($image_path, array(), array('style' => 'fullSmall'));
    //dsm($iptc_values);

    // TODO: needs to be finished
    foreach ($iptc_values as $key => $iptc) {
      $tokens['iptc_' . $key] = 'IPTC Field: ' . utf8_encode($iptc);
    }
    //dsm($tokens);
    return $tokens;
  }
}