<?php
// $Id: starrating.module,v 1.1 2010/12/20 20:13:52 pixture Exp $

/**
 * @file
 * Provides star rating field, formatter and widget using Field API.
 * star rating field is based on integer value and convert it to the HTML code
 * that displays series of icons.
 * The formatter supports not only star rating field type but also regular
 * integer (number) and list (number) field types.
 *
 * Following hook functions are provided.
 *
 * Field Type API: defines field type
 *  - hook_field_info()
 *  - hook_field_schema()
 *  - hook_field_is_empty()
 *  - hook_field_settings_form()
 *
 * Field Type API (Formatter): defines formatter (for displaying field)
 *  - hook_field_formatter_info()
 *  - hook_field_formatter_settings_form()
 *  - hook_field_formatter_settings_summary()
 *  - hook_field_formatter_view()
 *
 * Field Type API (Widget): defines widget (for entering value to field)
 *  - hook_field_widget_info()
 *  - hook_field_widget_form()
 */

define('DEFAULT_MAX_RATING_VALUE', 5);

/**
 *  Debug function
 */
/*function starrating_debug($str) {
  if(is_array($str) || is_object($str)) {
    error_log(print_r($str, TRUE) . "\r\n", 3, "/tmp/starrating.txt");
  }
  else {
    error_log($str . "\r\n", 3, "/tmp/starrating.txt");
  }
}*/

/*
 ****************************************************************************
 * Field Type API hooks
 ****************************************************************************
 */

/**
 * Implements hook_field_info().
 */
function starrating_field_info() {
  return array(
    'starrating_rating' => array(
      'label' => t('Star rating'),
      'default_widget' => 'starrating_rating_widget',
      'default_formatter' => 'starrating_rating_formatter',
    ),
  );
}

/**
 * Implements hook_field_is_empty().
 */
function starrating_field_is_empty($item, $field) {
  if ($item['value'] == NULL || (isset($item['value']) && empty($item['value']) && (string) $item['value'] !== '0')) {
    // 0 is OK
    return TRUE;
  }
  return FALSE;
}

/**
 * Implements hook_field_settings_form().
 */
function starrating_field_settings_form($field, $instance, $has_data) {

  $max_value = isset($field['settings']['max_value']) ? $field['settings']['max_value'] : DEFAULT_MAX_RATING_VALUE;

  $form['max_value'] = array(
    '#type' => 'select',
    '#title' => t('Maximum rating value'),
    '#options' => array(1 => '1', 2 => '2', 3 => '3', 4 => '4', 5 => '5', 6 => '6', 7 => '7', 8 => '8', 9 => '9', 10 => '10'),
    '#default_value' => $max_value,
    '#description' => t('Select the maximum rating value of this field.'),
  );
  return $form;
}

/*
 ****************************************************************************
 * Field Type API: Formatter
 ****************************************************************************
 */

/**
 * Implements hook_field_formatter_info().
 */
function starrating_field_formatter_info() {
  return array(
    'starrating_rating_formatter' => array(
      'label' => t('Star rating'),
      'field types' => array('number_integer', 'list_number', 'list_integer', 'starrating_rating'),
      'settings' => array(
        'fill_blank' => 1,
        'icon_type' => 'star',
        'icon_color' => 1,
      ),
    ),
    'starrating_rating_value' => array(
      'label' => t('Star rating value'),
      'field types' => array('number_integer', 'list_number', 'list_integer', 'starrating_rating'),
    ),
  );
}

/**
 * Implements hook_field_formatter_settings_form().
 */
function starrating_field_formatter_settings_form($field, $instance, $view_mode, $form, &$form_state) {
  $display = $instance['display'][$view_mode];
  $settings = $display['settings'];

  $element = array();

  $element['fill_blank'] = array(
    '#type' => 'checkbox',
    '#title' => t('Fill with blank icons'),
    '#default_value' => $settings['fill_blank'],
  );

  $element['icon_type'] = array(
    '#type' => 'select',
    '#title' => t('Icon type'),
    '#options' => array(
      'star' => t('Star'),
      'star-line' => t('Star (outline)'),
      'check' => t('Check'),
      'heart' => t('Heart'),
      'dollar' => t('Dollar'),
      'smiley' => t('Smiley'),
      'food' => t('Food'),
      'coffee' => t('Coffee'),
      'movie' => t('Movie'),
      'music' => t('Music'),
      'human' => t('Human'),
      'thumbs-up' => t('Thumbs Up'),
      'car' => t('Car'),
      'airplane' => t('Airplane'),
      'fire' => t('Fire'),
      'drupalicon' => t('Drupalicon'),
      'custom' => t('Custom'),
    ),
    '#default_value' => $settings['icon_type'],
    // '#prefix' => '<img src="/' . drupal_get_path('module', 'starrating') . '/icons/sample.png"  style="border: solid 1px #888" />',
    '#prefix' => '<img src="/' . drupal_get_path('module', 'starrating') . '/icons/sample.png" />',
  );
  $element['icon_color'] = array(
    '#type' => 'select',
    '#title' => t('Icon color'),
    '#options' => array(1 => '1', 2 => '2', 3 => '3', 4 => '4', 5 => '5', 6 => '6', 7 => '7', 8 => '8'),
    '#default_value' => $settings['icon_color'],
  );

  return $element;
}

/**
 * Implements hook_field_formatter_settings_summary().
 */
function starrating_field_formatter_settings_summary($field, $instance, $view_mode) {
  $display = $instance['display'][$view_mode];
  $settings = $display['settings'];

  $options = array(
    'type' => 'file',
    'weight' => 10,
    'group' => CSS_DEFAULT,
  );
  $css_file = $settings['icon_type'] . '.css';
  drupal_add_css(drupal_get_path('module', 'starrating') . '/icons/' . $css_file, $options);

  $min = 0;
  $max = isset($field['settings']['max_value']) ? $field['settings']['max_value'] : DEFAULT_MAX_RATING_VALUE;

  $rate = $max - 1; // sample data to be used for summary view

  $summary = starrating_field_formatter_execute($rate, $min, $max, $settings['icon_type'], $settings['icon_color'], $settings['fill_blank']);

  return $summary;
}

/**
 * Implements hook_field_formatter_view().
 */
function starrating_field_formatter_view($entity_type, $entity, $field, $instance, $langcode, $items, $display) {


  switch ($display['type']) {

    case 'starrating_rating_formatter':
  $settings = $display['settings'];
  $element = array();

  $options = array(
    'type' => 'file',
    'weight' => 10,
    'group' => CSS_DEFAULT,
  );
  $css_file = $settings['icon_type'] . '.css';
  drupal_add_css(drupal_get_path('module', 'starrating') . '/icons/' . $css_file, $options);

  $min = 0;
  $max = isset($field['settings']['max_value']) ? $field['settings']['max_value'] : DEFAULT_MAX_RATING_VALUE;

  if (!isset($items[0]['value']) || $items[0]['value'] == NULL || $items[0]['value'] === NULL) {
    $value = NULL;
  }
  else {
    $value = $items[0]['value'];
  }

  $output = starrating_field_formatter_execute($value, $min, $max, $settings['icon_type'], $settings['icon_color'], $settings['fill_blank']);
  $element[] = array('#markup' => $output);
  return $element;

    case 'starrating_rating_value':
      $element = array();
      $output = '<div class="starrating">' . $items[0]['value']  . '</div>';
      $element[] = array('#markup' => $output);
      return $element;
  }

}

/**
 * Implements hook_field_attach_view_alter().
 *
 * Alter the output to include "items" on null valued fields to allow the "No rating" text to come through.
 *
 */
function starrating_field_attach_view_alter(&$output, $context) {
  foreach (element_children($output) as $field_name) {
    if ($output[$field_name]['#field_type'] == 'starrating_rating') {
      if (empty($output[$field_name]['#items'])) {
        $output[$field_name]['#items'] = array(
          array('value' => NULL)
        );
      }
    }
  }
}

/**
 * Convert integer value to star rating HTML code
 *
 * @input
 *   $rate - integer value of rating
 * @output
 *   HTML code for star rating icons
 *   <div class="(icon_type)(icon_color)-on"></div> ...
 *
 */
function starrating_field_formatter_execute($rate, $min, $max, $icon_type, $icon_color, $fill_blank) {

  // if the rate value is 0, then return 'n/a'
  if ($rate === NULL) {
    return t('No rating');
  }

  $rate = intval($rate);

  // if the rate value not within the valid value range, return the original value
  if (($rate < $min) || ($rate > $max)) {
    return $rate;
  }

  $out = "\n";
  $out .= '<div class="starrating">';

  // add hidden text to support copy/paste and voice reading
  $out .= '<span style="position:absolute;left:-9999px">' . $rate . '</span>';

  for ($i = $min; $i < $max; $i++) {
    if (($i == $rate) && (!$fill_blank)) {
      break;
    }
    if ($i >= $rate) {
      $class = $icon_type . '-off';
    }
    else {
      $class = $icon_type . $icon_color . '-on';
    }
    if ($i % 2) {
      $class .= ' odd';
    }
    else {
      $class .= ' even';
    }
    $class .= ' s' . ($i + 1);

    $out .= '<div class="rate-image ' . $class . '"></div>';
  }
  $out .= "</div>\n";

  return $out;
}

/*
 ****************************************************************************
 * Field Type API: Widget
 ****************************************************************************
 */

/**
 * Implements hook_field_widget_info().
 */
function starrating_field_widget_info() {
  return array(
    'starrating_rating_widget' => array(
      'label' => t('Star rating'),
      'field types' => array('starrating_rating'),
    ),
  );
}

/**
 * On the widget form, we use "null" as a string for starrating fields that are "unset."
 * With this callback, we convert the "null" string to an actual NULL value for proper storage
 */
function _starrating_field_widget_form_to_null(&$form, &$form_state) {
  $fields = field_read_fields(array('module' => 'starrating'));
  foreach ($fields as $field_name => $field) {
    if (isset($form_state['values'][$field_name])) {
      foreach ($form_state['values'][$field_name]['und'] as $key => $value) {
        if ($value == 'null') {
          $form_state['values'][$field_name]['und'][$key] = NULL;
        }
      }
    }
  }
}

/*
 * Implements hook_field_widget_form().
 */
function starrating_field_widget_form(&$form, &$form_state, $field, $instance, $langcode, $items, $delta, $element) {
  $default_value = (isset($items[$delta]['value'])) ? $items[$delta]['value'] : 'null';

  $max_value = isset($field['settings']['max_value']) ? $field['settings']['max_value'] : DEFAULT_MAX_RATING_VALUE;

  $options = array();
  //handle "null" as a string so the form will validate
  $options['null'] = t('Not selected');
  for ($i = 0; $i <= $max_value; $i++) {
    $options[$i] = $i;
  }

  $element += array(
    '#type' => 'select',
    '#default_value' => $default_value,
    '#options' => $options,
  );

  if (isset($form['#submit'])) {
    array_unshift($form['#submit'], "_starrating_field_widget_form_to_null");
  }

  return array('value' => $element);
}