<?php
/**
 * @file
 * Provides core hooks and the like for the module
 * @copyright Copyright(c) 2011 Rowlands Group
 * @license GPL v2 http://www.fsf.org/licensing/licenses/gpl.html
 * @author Lee Rowlands leerowlands at rowlandsgroup dot com
 */

/**
 * Implements hook_help().
 */
function commerce_node_checkout_help($path, $arg) {
  switch ($path) {
    case 'admin/help#commerce_node_checkout':
      return t("Enables users to pay to publish content");
  }
}

/**
 * Implements hook_form_BASE_FORM_ID_alter().
 */
function commerce_node_checkout_form_node_form_alter(&$form, &$form_state, $form_id) {
  $node = $form['#node'];
  $enabled_products = commerce_node_checkout_get_products_by_type($node->type);
  // Don't show form if:
  // a) no selected products for the node type;
  // b) user has administer nodes permission;
  // c) node is already published; or
  // d) node has been saved already.
  if (!empty($enabled_products) && !user_access('administer nodes') && $node->status == 0 && empty($node->nid)) {
    $products = commerce_node_checkout_get_product_list($enabled_products);
    if (count($products) > 1) {
      $form['commerce_node_checkout_product'] = array(
        '#type' => 'select',
        '#title' => t('Listing options'),
        '#options' => $products,
        '#description' => t('Select your desired listing option.'),
      );
    }
    else {
      $form['commerce_node_checkout_product'] = array(
        '#type' => 'value',
        '#value' => array_shift(array_keys($products))
      );
    }
    $form['actions']['submit']['#submit'][] = 'commerce_node_checkout_node_insert_redirect';
  }
}

/**
 * Implements hook_form_FORM_ID_alter().
 */
function commerce_node_checkout_form_node_type_form_alter(&$form, $form_state) {
  $type = $form['#node_type'];
  $form['commerce_node_checkout'] = array(
    '#type' => 'fieldset',
    '#title' => t('Commerce Node Checkout'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
    '#group' => 'additional_settings',
  );

  $form['commerce_node_checkout']['commerce_node_checkout_products'] = array(
    '#type' => 'checkboxes',
    '#title' => t('Applicable products'),
    '#default_value' => variable_get('commerce_node_checkout_products_' . $type->type, array()),
    '#options' => commerce_node_checkout_get_product_list(),
    '#description' => t('Purchasing this product will enable the user to publish their node.'),
  );
}


/************************************************************
 * Non Core Hooks
 ************************************************************/
/**
 * Implements hook_commerce_line_item_type_info().
 */
function commerce_node_checkout_commerce_line_item_type_info() {

  $line_item_types['commerce_node_checkout'] = array(
    'name' => t('Commerce Node Checkout'),
    'description' => t('Example Line Item type of line item'),
    'product' => TRUE,
    'add_form_submit_value' => t('Place listing'),
    'base' => 'commerce_product_line_item',
  );
  return $line_item_types;
}

/************************************************************
 * Module functions
 ************************************************************/
/**
 * Util function to fetch commerce_node_checkout_products for a node type
 *
 * @param string $type
 *   Node type machine name
 *
 * @return array
 *   Array of enabled products keyed by product id
 */
function commerce_node_checkout_get_products_by_type($type) {
  return variable_get('commerce_node_checkout_products_' . $type, array());
}

/**
 * Util to fetch the a list of available products.
 *
 * @param array $available_products
 *   array of product ids
 *
 * @return array
 *   Array of product names keyed by product id
 */
function commerce_node_checkout_get_product_list($available_products = array()) {
  $options = array();

  // Loop through all product matches.
  foreach (commerce_product_match_products(array('field_name' => 'commerce_node_checkout_products'),
                                           array('settings' => array('referenceable_types' => array('commerce_node_checkout'))),
                                           '', 'contains', $available_products) as $product_id => $data) {
    // Add them to the options list.
    $options[$product_id] = check_plain($data['title']);
  }

  return $options;
}

/**
 * Form submission handler to add the node to the user's cart
 */
function commerce_node_checkout_node_insert_redirect($form, &$form_state) {
  $node = $form_state['node'];
  $product_id = $form_state['values']['commerce_node_checkout_product'];
  $product = commerce_product_load($product_id);
  commerce_node_checkout_add_node($node, $product);
  $form_state['redirect'] = 'checkout';
}

/**
 * Adds a node to a line item and the user's cart
 *
 * @param object $node
 *   The node object to be associated with the line item
 * @param object $product
 *   The product chosen by the user (optional)
 *
 * @return object
 *   Returns the commerce_order object
 */
function commerce_node_checkout_add_node($node, $product) {
  global $user;

  // Create our new line item.
  $line_item = commerce_product_line_item_new($product, 1, 0, array(), 'commerce_node_checkout');

  // Set the node_reference field value.
  $line_item->commerce_node_checkout_node[LANGUAGE_NONE][0]['nid'] = $node->nid;

  // Let other modules have a go.
  drupal_alter('commerce_node_checkout_line_item', $line_item, $product, $node);

  // Add to cart.
  $line_item = commerce_cart_product_add($user->uid, $line_item, FALSE);

  // Load the order for returning it.
  $order = commerce_cart_order_load($user->uid);
  return $order;
}