price_in_time.module

<?php

/**
 * @file
 * Primary module hooks for Price in Time module.
 */

# Drupal Core.
use Drupal\Core\Form\FormStateInterface;

# Commerce Product.
use Drupal\commerce_product\Entity\ProductVariation;

/**
 * Implements hook_preprocess_page().
 * 
 * @param $variables
 * 
 * Some style need to be added to the configuration page of the
 * time slots, so we can inject our custom library to the specific
 * route (based on route name).
 * 
 */
function price_in_time_preprocess_page(&$variables) {
  if (\Drupal::routeMatch()->getRouteName() === 'price_in_time.product_type_time_slots') {
    $variables['#attached']['library'][] = 'price_in_time/price_in_time';
  }
}

/**
 * Implements hook_form_alter().
 * 
 * @param $form
 * @param FormStateInterface $form_state
 * @param $form_id
 * 
 * Edit the form page of the product/variation to insert the custom
 * prices on the relative slot of time. This will be showed only if
 * the node is not new and only if it is a product/variation.
 * 
 */
function price_in_time_form_alter(&$form, FormStateInterface $form_state, $form_id) {

  if (\Drupal::service('router.admin_context')->isAdminRoute() &&
      method_exists($form_state->getFormObject(), 'getEntity') &&
      _price_in_time_check_bundle_enabled($form_state->getFormObject()->getEntity()->bundle())) {

    #--------------------------------------
    # define drupal front URL
    #--------------------------------------
    global $base_url;

    if (($entity = $form_state->getFormObject()->getEntity()) && !$entity->isNew()) {
      if (method_exists($entity, 'getVariations') &&
          count($entity->getVariations()) > 1) {

          # return if there are some other variations.
          return;
      }

      #--------------------------------------
      # define drupal 'fieldset' element
      #--------------------------------------
      $form['price_in_time__slots'] = [
        '#type' => 'fieldset',
        '#title' => t('Insert the price for different time slots'),
        '#description' => t('
          You can edit this configuration on the module page:
          <a href="'.$base_url.'/admin/commerce/config/time-slots">
            Price in Time configuration page
          </a>'),
        '#prefix' => '<div id="price-in-time--slots">',
        '#suffix' => '</div>',
        '#weight' => -100, # we want this at the top.
      ];

      foreach (_price_in_time_get_times_slots($entity->bundle()) as $key => $slot) {

        #--------------------------------------
        # define drupal 'markup' element
        #--------------------------------------
        $form['price_in_time__slots'][$key]['times_info'] = [
          '#markup' => '
            <br> <!-- break the line every slot -->
            <div class="price_in_time__slots_form_element">
              FROM '.$slot['start'].' to '.$slot['end'].' (24H)
            </div>',
        ];
        #--------------------------------------
        # define drupal 'price' element
        #--------------------------------------
        $form['price_in_time__slots'][$key]['price'] = [
          '#type' => 'commerce_price',
          '#title' => t('Owerride the price for this slot:'),
          '#default_value' =>
            _price_in_time_get_slot_price_default_value(
              $slot['uuid'],
              _price_in_time_get_sku_key_from_product_or_variation($entity)
            ),
        ];
        #--------------------------------------
        # define drupal 'hidden' element
        #--------------------------------------
        $form['price_in_time__slots'][$key]['uuid'] = [
          '#type' => 'hidden',
          '#value' => $slot['uuid'],
        ];
      }

      foreach (array_keys($form['actions']) as $action) {
        if ($action != 'preview' && isset($form['actions'][$action]['#type']) && $form['actions'][$action]['#type'] === 'submit') {
          $form['actions'][$action]['#submit'][] = 'price_in_time_form_submit';
        }
      }

      $form['#tree'] = TRUE;
    }

    else {
      #--------------------------------------
      # define drupal 'fieldset' element
      #--------------------------------------
      $form['price_in_time__slots'] = [
        '#type' => 'fieldset',
        '#title' => t('Information:'),
        '#description' => t('
          You have enabled this product variation on <b>Price in Time</b> module, after the save you 
          should view the form for the prices.<br>
          You can edit this configuration on the module page:
          <a href="'.$base_url.'/admin/commerce/config/time-slots">
            Price in Time configuration page
          </a>'),
        '#prefix' => '<div id="price-in-time--slots">',
        '#suffix' => '</div>',
        '#weight' => -100, # we want this at the top.
      ];
    }
  }
}

/**
 * Implements hook_form_submit().
 * 
 * @param $form
 * @param FormStateInterface $form_state
 * 
 * This will be called after the submit of the form (on the 
 * node update operations).
 * 
 */
function price_in_time_form_submit($form, FormStateInterface $form_state) {

  if (method_exists($form_state->getFormObject(), 'getEntity')) {

    $entity = $form_state->getFormObject()->getEntity();
    $prices_values = $form_state->getValue('price_in_time__slots');

    foreach ($prices_values as $key => $price) {

      $product_variation_sku = _price_in_time_get_sku_key_from_product_or_variation($entity);

      if (!empty($price['price']['number']) && $product_variation_sku) {

        $connection = \Drupal::database();
        $transaction = $connection->startTransaction();

        try {

          $product_variation = $entity->bundle();
          $slot_uuid = $price['uuid'];
          $number = $price['price']['number'];
          $currency_code = $price['price']['currency_code'];
          $created = \Drupal::time()->getRequestTime();

          if (!_price_in_time_check_row_existance($connection, $slot_uuid, $product_variation_sku)) {

            $connection
              ->insert('commerce_product_variation_slots_data')
              ->fields([
                'product_variation_sku' => $product_variation_sku,
                'product_variation' => $product_variation,
                'slot_uuid' => $slot_uuid,
                'number' => $number,
                'currency_code' => $currency_code,
                'created' => $created,
            ])->execute();
          } else {

            $connection->update('commerce_product_variation_slots_data')
              ->fields([
                'number' => $number,
                'currency_code' => $currency_code,
              ])
              ->condition('slot_uuid', $slot_uuid)
              ->condition('product_variation_sku', $product_variation_sku)
              ->execute();
          }
        }

        catch (Exception $exception) {
          $transaction->rollBack();

          # Here we go to an error, log this into the watchdog.
          # Sure this will be usefull...
          \Drupal::logger('[PRICE-IN-TIME]')
            ->error('Insert error, check the message: ' . $exception->getMessage());
        }

        # Commit the transaction by unsetting the $transaction variable.
        unset($transaction);
      }

      # Use the default price if the user not set the price
      # on the relative form (for the slot). Delete the element
      # from the database table.
      else {

        \Drupal::database()
          ->delete('commerce_product_variation_slots_data')
          ->condition('slot_uuid', $price['uuid'])
          ->condition('product_variation_sku', _price_in_time_get_sku_key_from_product_or_variation($entity))
          ->condition('product_variation', $entity->bundle())
          ->execute();
      }
    }
  }
}

/**
 * Implements _hook_check_row_existance().
 *
 * @param $connection
 * @param string $slot_uuid
 * @param string $product_variation_sku
 * @return bool
 * 
 * Return a boolean to check if the row exists in the custom table named
 * commerce_product_variation_slots_data, this because we need to update 
 * the record if exists or insert new one if not.
 *
 */
function _price_in_time_check_row_existance($connection, $slot_uuid, $product_variation_sku) {

  return $connection
    ->select('commerce_product_variation_slots_data', 'commerce_product_slots')
    ->condition('commerce_product_slots.slot_uuid', $slot_uuid)
    ->condition('commerce_product_slots.product_variation_sku', $product_variation_sku)
    ->countQuery()
    ->execute()
    ->fetchField() > 0 ?: 0;
}

/**
 * Implements _hook_get_sku_key_from_product_or_variation().
 *
 * @param $entity
 * @return string
 * 
 * Return the SKU of the single variation, in any case; in the commerce
 * product case and in the multiple variations case.
 *
 */
function _price_in_time_get_sku_key_from_product_or_variation($entity) {
  return ($entity->getEntityTypeId() === 'commerce_product' && count($entity->getVariations()) === 1) ?
    $entity->getVariations()[0]->getSku() : $entity->getSku();
}

/**
 * Implements _hook_check_bundle_enabled().
 *
 * @param string $bundle
 * @return bool
 * 
 * Return a boolean so we can know if the specific variation
 * is enabled or not (based on the configuration).
 *
 */
function _price_in_time_check_bundle_enabled($bundle) {
  return @\Drupal::config('price_in_time.settings')->get($bundle)['enabled'];
}

/**
 * Implements _hook_get_times_slots().
 *
 * @param string $bundle
 * @return array
 * 
 * Return all the times related to the single variation bundle, so
 * an array with this structure: 
 * 
 * key => [
 *  start_time,
 *  end_time,
 *  free_shipping,
 * ]
 *
 */
function _price_in_time_get_times_slots($bundle) {
  return @\Drupal::config('price_in_time.settings')->get($bundle)['times'];
}

/**
 * Implements _hook_get_slot_price_default_value().
 *
 * @param string $uuid
 * @return array
 * 
 * Return the price (number and currency code) related to the 
 * single product in the specific slot uuid. Return empty price
 * if it was not set prevs.
 *
 */
function _price_in_time_get_slot_price_default_value($uuid, $sku) {
  return
    is_array(
      $default_price_value = \Drupal::database()
        ->select('commerce_product_variation_slots_data', 'commerce_product_slots')
        ->condition('commerce_product_slots.slot_uuid', $uuid)
        ->condition('commerce_product_slots.product_variation_sku', $sku)
        ->fields('commerce_product_slots', ['number', 'currency_code'])
        ->execute()
        ->fetchAssoc()
    ) ? $default_price_value : [
      'number' => '',        # set an empty value for the price.
      'currency_code' => '', # get the default value.
    ];
}