<?php
// $Id: computed_field.module,v 1.19.2.7 2010-10-13 03:53:19 moonshine Exp $

/**
 * Implements field hook_field_info().
 */
function computed_field_field_info() {
  return array(
    'computed' => array(
      'label' => t('Computed'),
      'description' => t('Create field data via PHP code.'),
      'settings' => array(
        'code' => '$entity_field[0][\'value\'] = "";',
        'display_format' => '$display_output = $entity_field_item[\'value\'];',
        'store' => 1,
        'database' => array(
          'data_type' => 'varchar',
          'data_length' => 32,
          'data_not_NULL' => FALSE,
          'data_default' => NULL,
          'data_sortable' => TRUE,
          'data_index' => FALSE,
        ),
      ),
      'default_widget' => 'computed',
      'default_formatter' => 'computed_field_default',
    ),
  );
}

/**
 * Implements of hook_field_settings_form().
 */
function computed_field_field_settings_form($field, $instance, $has_data) {
  $form = array();
  $compute_func = 'computed_field_' . $field['field_name'] . '_compute';
  $display_func = 'computed_field_' . $field['field_name'] . '_display';
  $settings = $field['settings'];

  $form['#element_validate'] = array('computed_field_field_settings_form_validate');
  
  $form['code'] = array(
    '#type' => 'textarea',
    '#rows' => 15,
    '#title' => t('Computed Code (PHP)'),
    '#description' => t('Some variables available to your code include: <code>@fields</code>. To set the value of the field, set <code>@entity_field</code>.  For multi-value computed fields continue with <code>@entity_field_multi</code>.  Here\'s a simple example which sets the computed field\'s value to the value of the sum of the number fields (<code>@field_a</code> and <code>@field_b</code>) in a node entity:<p><code>@example</code><p>Alternately, this code can be supplied by your own custom function named: <code>@compute_func()</code>', 
      array('@fields' => '$entity, $entity_type, $entity_lang, &$entity_field and $langcode',
        '@entity_field' => '$entity_field[0][\'value\']',
        '@entity_field_multi' => '$entity_field[1][\'value\']',
        '@field_a' => 'field_a',
        '@field_b' => 'field_b',
        '@example' => '$entity_field[0][\'value\'] = $entity->field_a[\'und\'][0][\'value\'] + $entity->field_b[\'und\'][0][\'value\'];',
        '@compute_func' => $compute_func)),
    '#default_value' => !empty($settings['code']) ? $settings['code'] : '$entity_field[0][\'value\'] = "";',
    '#access' => !function_exists($compute_func),
  );
  if (function_exists($compute_func)) {
    $form['compute_func'] = array(
    '#type' => 'item',
    '#markup' => t('<strong>This field is COMPUTED using <code>@compute_func()</code>.</strong>', array('@compute_func' => $compute_func)),
    );
  }
  $form['display_format'] = array(
    '#type' => 'textarea',
    '#title' => t('Display Code (PHP)'),
    '#description' => t('This code should assign a string to the <code>@display_output</code> variable, which will be printed when the field is displayed. The raw computed value of the field is in <code>@value</code>.  <strong>Note:</strong> this code has no effect if you use the "Raw computed value" display formatter.<p> Alternately, this code can be supplied by your own custom function named: <code>@display_func()</code>', 
      array('@display_output' => '$display_output',
            '@value' => '$entity_field_item[\'value\']',
            '@display_func' => $display_func)),
    '#default_value' => !empty($settings['display_format']) ? $settings['display_format'] : '$display_output = $entity_field_item[\'value\'];',
    '#access' => !function_exists($display_func),
  );
  if (function_exists($display_func)) {
    $form['display_func'] = array(
      '#type' => 'item',
      '#markup' => t('<strong>This field is DISPLAYED using <code>@display_func()</code>.</strong>', array('@display_func' => $display_func)),
      );
  }
  $form['store'] = array(
    '#type' => 'checkbox',
    '#title' => t('Store using the database settings below (required for Views use):'),
    '#default_value' => is_numeric($settings['store']) ? $settings['store'] : 1 ,
    '#disabled' => $has_data,
  );
  $form['database'] = array('#type' => 'fieldset', '#title' => t('Database Storage Settings'));
  
  if ($has_data) {
    $form['database']['warning'] = array(
      '#type' => 'item',
      '#markup' => t('<strong>**This field currently has stored data, so modifications to its DB settings are not allowed.**</strong>'),
    );
  }
  $form['database']['data_type'] = array(
    '#type' => 'radios',
    '#title' => t('Data Type'),
    '#description' => t('The SQL datatype to store this field in.'),
    '#default_value' => !empty($settings['database']['data_type']) ? $settings['database']['data_type'] : 'varchar',
    '#options' => array('int' => 'int', 'float' => 'float', 'varchar' => 'varchar', 'text' => 'text', 'longtext' => 'longtext'),
    '#required' => FALSE,
    '#disabled' => $has_data,
  );
  $form['database']['data_length'] = array(
    '#type' => 'textfield',
    '#title' => t('Data Length'),
    '#default_value' => !empty($settings['database']['data_length']) ? $settings['database']['data_length'] : NULL,
    '#required' => FALSE,
    '#disabled' => $has_data,
  );
  $form['database']['data_default'] = array(
    '#type' => 'textfield',
    '#title' => t('Default Value'),
    '#default_value' => $settings['database']['data_default'],
    '#required' => FALSE,
    '#disabled' => $has_data,
  );
  $form['database']['data_not_NULL'] = array(
    '#type' => 'checkbox',
    '#title' => t('Not NULL'),
    '#default_value' => is_numeric($settings['database']['data_not_NULL']) ? $settings['database']['data_not_NULL'] : FALSE,
    '#disabled' => $has_data,
  );
  $form['database']['data_sortable'] = array(
    '#type' => 'checkbox',
    '#title' => t('Sortable'),
    '#default_value' => is_numeric($settings['database']['data_sortable']) ? $settings['database']['data_sortable'] : TRUE,
    '#disabled' => $has_data,
  );
  $form['database']['data_index'] = array(
    '#type' => 'checkbox',
    '#title' => t('Indexed (adds a simple DB index on on the computed values)'),
    '#default_value' => is_numeric($settings['database']['data_index']) ? $settings['database']['data_index'] : FALSE,
    '#disabled' => $has_data,
  );
  return $form;
}

/**
* Implements the #element_validate callback for computed_field_field_settings_form().
*/
function computed_field_field_settings_form_validate($element, &$form_state) {
  $settings = $form_state['values']['field']['settings'];
  if ($settings['store']) {
    if (empty($settings['database']['data_type'])) {
      form_set_error('field][settings][data_type', t('To store this field in the database, please specify a data type.'));
    }
    if (!($settings['database']['data_type'] == 'text' || $settings['database']['data_type'] == 'longtext') && (empty($settings['database']['data_length']) || !is_numeric($settings['database']['data_length']))) {
      form_set_error('field][settings][database][data_length', t('To store this field in the database, please specify the data length.'));
    }
    if (($settings['database']['data_type'] == 'int' || $settings['database']['data_type'] == 'float') && (!empty($settings['database']['data_default']) && !is_numeric($settings['database']['data_default']))) {
      form_set_error('field][settings][database][data_default', t('Your default value should be numeric given your data type.'));
    }
  }
}

/**
 * Implements field hook_field_load().
 */
function computed_field_field_load($entity_type, $entities, $field, $instances, $langcode, &$items, $age) {
  $settings = $field['settings'];
  // Compute field values on load if they aren't stored in the database
  if (!$settings['store']) {
    foreach ($entities as $etid => $entity) {
      _computed_field_compute_value($entity_type, $entity, $field, $instances, $langcode, &$items[$etid]);
    }
  }
}

/**
 * Implements field hook_field_prepare_view().
 */
function computed_field_field_prepare_view($entity_type, $entities, $field, $instances, $langcode, &$items) {
  // Compute field values in case user is "previewing" an entity
  foreach ($entities as $etid => $entity) {
    if (isset($entity->op) && $entity->op == 'Preview') {
      _computed_field_compute_value($entity_type, $entity, $field, $instances, $langcode, &$items[$etid]);
    }
  }
}

/**
 * Implements field hook_field_presave().
 */
function computed_field_field_presave($entity_type, $entity, $field, $instance, $langcode, &$items) {
  _computed_field_compute_value($entity_type, $entity, $field, $instance, $langcode, &$items);
}

/**
 * Implements field hook_field_widget_info().
 */
function computed_field_field_widget_info() {
  return array(
    'computed' => array(
      'label' => t('Computed'),
      'field types' => array('computed'),
      'behaviors' => array(
        'multiple values' => FIELD_BEHAVIOR_CUSTOM,
        'default value' => FIELD_BEHAVIOR_NONE,
      ),
    ),
  );
}

/**
 * Implements field hook_field_widget_form().
 */

function computed_field_field_widget_form(&$form, &$form_state, $field, $instance, $langcode, $items, $delta, $element) {

  // If there are no items yet, add a null item value to avoid
  // preview errors when selecting a different language
  if (empty($items)) $items[0]['value'] = NULL;

  foreach ($items as $item_delta => $item) {
    $element[$item_delta]['value'] = array(
      '#type' => 'value',
      '#tree' => TRUE,
      '#default_value' => isset($item['value']) ? $item['value'] : NULL,
    );
  }
  return $element;
}

/**
 * Implements hook_field_formatter_info().
 */
function computed_field_field_formatter_info() {
  return array(
    'computed_field_default' => array(
      'label' => t('Default'),
      'field types' => array('computed'),
    ),
    'computed_field_plain' => array(
      'label' => t('Plain text'),
      'field types' => array('computed'),
    ),
    'computed_field_markup' => array(
      'label' => t('Filtered markup'),
      'field types' => array('computed'),
    ),
    'computed_field_computed_value' => array(
      'label' => t('Raw computed value'),
      'field types' => array('computed'),
    ),
  );
}

/**
 * Implements hook_field_formatter_view().
 */
function computed_field_field_formatter_view($entity_type, $entity, $field, $instance, $langcode, $items, $display) {
  $element = array();

  // Special case formatter that returns the raw computed values without any display code processing
  if ($display['type'] == "computed_field_computed_value") {
    foreach ($items as $delta => $item) {
      $element[$delta] = array('#markup' => $item['value']);
    }
    return $element;
  }

  // Other display formatters which run through display code processing
  // Check if the value is to be formatted by a display function outside the DB
  $display_func = 'computed_field_' . $field['field_name'] . '_display';
  if (function_exists($display_func)) $display_in_code = TRUE;
  else $display_in_code = FALSE;
  
  // Loop the items to display
  foreach ($items as $delta => $item) {
  
    // For "some" backwards compatibility
    $entity_field_item = $item;
    
    // Setup a variable with the entity language if available
    if (isset($entity->language)) $entity_lang = $entity->language;
    else $entity_lang = 'und';

    // Execute the display code
    $display_output = NULL;
    if ($display_in_code) {
      $display_output = $display_func($field, $entity_field_item, $entity_lang, $langcode);
    }
    else {
      eval($field['settings']['display_format']);
    }
    
    // Output the formatted display item
    switch ($display['type']) {
      case 'computed_field_default':
          $element[$delta] = array('#markup' => $display_output);
        break;
      case 'computed_field_plain':
          $element[$delta] = array('#markup' => check_plain($display_output));
        break;
      case 'computed_field_markup':
          $element[$delta] = array('#markup' => check_markup($display_output));
        break;
    }
  }
  return $element;
}

/**
 * Implements field hook_field_is_empty().
 */
function computed_field_field_is_empty($item, $field) {
  $data_type = $field['settings']['database']['data_type'];
  if ($data_type == 'int' || $data_type == 'float') {
    return !is_numeric($item['value']);
  }
  return empty($item['value']);
}

/**
 * Implements hook_tokens().
 */
function computed_field_token_info() {
  $types['computed'] = array(
    'name' => t("Computed"),
    'description' => t("Tokens related to Computed fields."),
    'needs-data' => 'node',
  );
  $fields = field_info_fields();
  foreach ($fields as $field_name => $field) {
    if ($field['module'] == "computed_field") {

      $node[str_replace('_', '-', $field_name)] = array(
        'name' => t("Computed: %field_name", array('%field_name' => $field_name)),
        'description' => t("Computed field %field_name value.", array('%field_name' => $field_name)),
        'type' => 'computed',
      );
      $computed['rawvalue'] = array(
        'name' => t("Raw computed value"),
        'description' => t("Computed field %field_name raw value.", array('%field_name' => $field_name)),
      );
    }
  }
  return array(
    'types' => $types,
    'tokens' => array('node' => $node, 'computed' => $computed),
  );
}

/**
 * Implements hook_tokens().
 */
function computed_field_tokens($type, $tokens, array $data = array(), array $options = array()) {
  $replacements = array();
  $sanitize = !empty($options['sanitize']);
  $lang = $options['language']->language;
  $fields = field_info_fields();
  foreach ($fields as $field_name => $field) {
    if ($field['module'] == "computed_field") {
      $computed_fields[] = str_replace('_', '-', $field_name);
    }
  }
  foreach ($tokens as $name => $original) {
    // For normal display output
    if (in_array($name, $computed_fields)) {
      $field_name = str_replace('-', '_', $name);
      $entity_field_item = $data[$type]->{$field_name}[$lang][0];
      $field = $fields[$field_name];
      // Check if the value is to be formatted by a display function outside the DB
      $display_func = 'computed_field_' . $field_name . '_display';
      if (function_exists($display_func))  {
        $display_output = $display_func($field, $entity_field_item);
      }
      else {
        eval($field['settings']['display_format']);
      }
      $replacements[$original] = $sanitize ? check_plain($display_output) : $display_output;
    }
    // For raw value output
    elseif (in_array(str_replace(':rawvalue', '', $name), $computed_fields)) {
      $field_name = str_replace('-', '_', str_replace(':rawvalue', '', $name));
      $replacements[$original] = $sanitize ? check_plain($data[$type]->{$field_name}[$lang][0]['value']) : $data[$type]->{$field_name}[$lang][0]['value'];
    }
  }
  return $replacements;
}

/**
 * Private function to compute the fields value.
 */
function _computed_field_compute_value($entity_type, $entity, $field, $instance, $langcode, &$items) {
  $settings = $field['settings'];

  // Setup a variable with the field values
  $entity_field =& $items;
  
  // Setup a variable with the entity language if available
  if (isset($entity->language)) $entity_lang = $entity->language;
  else $entity_lang = 'und';
  
  // Allow the value to be computed from code not stored in DB
  $compute_func = 'computed_field_' . $field['field_name'] . '_compute';
  if (function_exists($compute_func)) {
    $compute_func($entity_field, $entity_type, $entity, $field, $instance, $langcode, $items);
  }
  else {
    if (isset($settings['code'])) {
      eval($settings['code']);
    }
  }
}