<?php
// $Id: duration.module,v 1.12 2008/10/08 06:36:24 jpetso Exp $

/**
 * @file
 * A CCK field for entering time durations.
 *
 * Copyright 2008 by Jakob Petsovits <jpetso@gmx.at>
 * Distributed under the GNU General Public Licence version 2 or higher,
 * as published by the FSF on http://www.gnu.org/copyleft/gpl.html
 */


/**
 * Implementation of hook_field_info().
 */
function duration_field_info() {
  return array(
    'duration' => array(
      'label' => t('Duration'),
      'description' => t('Store a duration in the database as an ISO duration.'),
    ),
  );
}

/**
 * Implementation of hook_field_settings().
 */
function duration_field_settings($op, $field) {
  switch ($op) {
    case 'form':
      $form = array();
      return $form;

    case 'save':
      return array();

    case 'database columns':
      return array(
        'iso8601' => array(
          'type'     => 'varchar',
          'length'   => '64',
          'not null' => TRUE,
          'default'  => '',
        ),
        'approx_seconds' => array(
          'type'     => 'int',
          'unsigned' => TRUE,
          'not null' => TRUE,
          'default'  => 0,
          'sortable' => TRUE,
        ),
      );

    case 'views data':
      $data = content_views_field_views_data($field);
      $db_info = content_database_info($field);
      $table_alias = content_views_tablename($field);

      // Set our own field handler so that loads the Duration object (like in
      // hook_field($op='load')), because CCK's standard field handler doesn't
      // do that.
      $data[$table_alias][$field['field_name'] .'_iso8601']['field']['handler'] = 'duration_handler_field';

      return $data;
  }
}

/**
 * Implementation of hook_field().
 */
function duration_field($op, &$node, $field, &$items, $teaser, $page) {
  switch ($op) {
    case 'load':
      // Add a third property in addition to 'iso8601' and 'approx_seconds':
      // 'duration', containing the duration object for the ISO string.
      foreach ($items as $delta => $item) {
        $items[$delta]['duration'] = duration_create($item['iso8601']);
      }
      return array($field['field_name'] => $items);
  }
}

/**
 * Implementation of hook_content_is_empty().
 */
function duration_content_is_empty($item, $field) {
  if (empty($item['iso8601'])) {
    return TRUE;
  }
  return FALSE;
}


/**
 * Implementation of hook_field_formatter_info().
 */
function duration_field_formatter_info() {
  return array(
    'default' => array(
      'label' => t('List of metrics ("2 months, 15 days, ...")'),
      'field types' => array('duration'),
      'multiple values' => CONTENT_HANDLE_CORE,
    ),
    'hms' => array(
      'label' => t('HMS ("3h20m45s")'),
      'field types' => array('duration'),
      'multiple values' => CONTENT_HANDLE_CORE,
    ),
    'colons' => array(
      'label' => t('Time with colons ("3:20:45")'),
      'field types' => array('duration'),
      'multiple values' => CONTENT_HANDLE_CORE,
    ),
  );
}

/**
 * Implementation of hook_theme().
 */
function duration_theme() {
  return array(
    'duration_formatter_default' => array(
      'arguments' => array('element' => NULL),
    ),
    'duration_formatter_hms' => array(
      'arguments' => array('element' => NULL),
    ),
    'duration_formatter_colons' => array(
      'arguments' => array('element' => NULL),
    ),
  );
}

/**
 * Theme function for the 'default' duration field formatter.
 */
function theme_duration_formatter_default($element) {
  if (isset($element['#node']->duration)) { // loaded by duration_handler_field
    $element['#item']['duration'] = $element['#node']->duration;
  }
  return duration_format_list($element['#item']['duration']);
}

/**
 * Theme function for the 'hms' duration field formatter.
 */
function theme_duration_formatter_hms($element) {
  if (isset($element['#node']->duration)) { // loaded by duration_handler_field
    $element['#item']['duration'] = $element['#node']->duration;
  }
  return duration_format_hms($element['#item']['duration']);
}

/**
 * Theme function for the 'colons' duration field formatter.
 */
function theme_duration_formatter_colons($element) {
  if (isset($element['#node']->duration)) { // loaded by duration_handler_field
    $element['#item']['duration'] = $element['#node']->duration;
  }
  return duration_format_custom($element['#item']['duration'], '%h:%M:%S');
}


/**
 * Implementation of hook_widget_info().
 */
function duration_widget_info() {
  return array(
    'duration_combo' => array(
      'label' => t('Text Fields'),
      'field types' => array('duration'),
      'multiple values' => CONTENT_HANDLE_CORE,
    ),
  );
}

/**
 * Implementation of hook_widget_settings().
 */
function duration_widget_settings($op, $widget) {
  switch ($op) {
    case 'form':
      $form = array();

      if ($widget['type'] == 'duration_combo') {
        $form['use_weeks'] = array(
          '#type' => 'checkbox',
          '#title' => t('Use weeks instead of months'),
          '#description' => t('The date part of a duration can either be specified using one of the (mutually exclusive) formats "years/months/days" or "years/weeks/days". By default, the former one is used, but you can switch to the weeks format by checking this option.'),
          '#default_value' => isset($widget['use_weeks']) ? $widget['use_weeks'] : 0,
          '#required' => TRUE,
        );

        $metrics = duration_metrics('months');
        $metric_options = array();
        foreach ($metrics as $metric) {
          if ($metric == 'months') {
            $metric_options[$metric] = t('!months/!weeks', array(
              '!months' => duration_metric_t('months'),
              '!weeks' => duration_metric_t('weeks'),
            ));
          }
          else {
            $metric_options[$metric] = duration_metric_t($metric);
          }
        }

        $form['largest_metric'] = array(
          '#type' => 'select',
          '#title' => t('Largest metric that can be entered'),
          '#options' => $metric_options,
          '#default_value' => $widget['largest_metric']
                              ? $widget['largest_metric']
                              : 'years',
          '#required' => TRUE,
        );
        $form['smallest_metric'] = array(
          '#type' => 'select',
          '#title' => t('Smallest metric that can be entered'),
          '#options' => $metric_options,
          '#default_value' => $widget['smallest_metric']
                              ? $widget['smallest_metric']
                              : 'seconds',
          '#required' => TRUE,
        );
      }
      else { // not a duration combo, assign arbitrary default values instead.
        $form['use_weeks'] = array('#type' => 'hidden', '#value' => 0);
        $form['largest_metric'] = array('#type' => 'hidden', '#value' => 'years');
        $form['smallest_metric'] = array('#type' => 'hidden', '#value' => 'seconds');
      }
      return $form;

    case 'validate':
      // Make sure the smallest metric is at least as small as the largest metric.
      $metrics = duration_metrics('months', 'descending');
      foreach ($metrics as $metric) {
        if ($metric == $widget['largest_metric']) {
          // Encountered the lartest metric first, that's how it should be.
          break;
        }
        if ($metric == $widget['smallest_metric']) {
          // Encountered the smallest metric first, which means it's larger
          // than the largest metric. That can't be allowed, obviously.
          form_set_error('smallest_metric',
            t('The "smallest metric" must not be greater than the "largest metric".')
          );
        }
      }
      break;

    case 'save':
      return array('use_weeks', 'largest_metric', 'smallest_metric');
  }
}

/**
 * Implementation of hook_widget().
 */
function duration_widget(&$form, &$form_state, $field, $items, $delta = 0) {
  if ($field['widget']['type'] == 'duration_combo') {
    // If we're using weeks format, make sure everything complies to that.
    if ($field['widget']['use_weeks']) {
      if ($field['widget']['largest_metric'] == 'months') {
        $field['widget']['largest_metric'] = 'weeks';
      }
      if ($field['widget']['smallest_metric'] == 'months') {
        $field['widget']['smallest_metric'] = 'weeks';
      }
      if (isset($items[$delta]['duration'])) {
        $items[$delta]['duration']->set_type('weeks');
      }
      else {
        $items[$delta]['duration'] = duration_create('P0W');
      }
    }
    $element = array(
      '#type' => 'duration_combo',
      '#default_value' => isset($items[$delta]['duration'])
                          ? $items[$delta]['duration']
                          : NULL,
      '#largest_metric' => isset($field['widget']['largest_metric'])
                            ? $field['widget']['largest_metric']
                            : 'years',
      '#smallest_metric' => isset($field['widget']['smallest_metric'])
                            ? $field['widget']['smallest_metric']
                            : 'seconds',
      '#element_validate' => array('duration_combo_validate'),
    );
  }
  return $element;
}

/**
 * Additional 'validate' callback for 'duration_combo' widgets.
 * Transforms the original element form value to the CCK item (array) format.
 */
function duration_combo_validate($element, &$form_state) {
  $item = array(
    'duration' => $element['#value'],
    'iso8601' => $element['#value']->to_iso(),
    'approx_seconds' => $element['#value']->to_single_metric('seconds'),
  );
  form_set_value($element, $item, $form_state);
}


/**
 * Implementation of hook_menu().
 */
function duration_menu() {
  $items['duration-cck'] = array(
    'title' => 'Duration CCK field test form',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('duration_test_form'),
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );
  return $items;
}

/**
 * Implementation of hook_views_api().
 */
function duration_views_api() {
  return array(
    'api' => 2.0,
    'path' => drupal_get_path('module', 'duration') . '/views',
  );
}