<?php
// $Id: draggableviews.module,v 1.6.2.9 2009-03-08 14:47:18 sevi Exp $

/**
 * @file
 * Draggableviews module provides a style plugin for views.
 * With this plugin rows become draggable and can be organized in complex structures.
 */

require_once './'. drupal_get_path('module', 'draggableviews') ."/draggableviews.inc";
require_once './'. drupal_get_path('module', 'draggableviews') ."/draggableviews_theme.inc";

/**
 * Display help and module information
 * 
 * @param @path
 *   Which path of the site we're displaying help.
 * @param arg
 *   Array that holds the current path as would be returned from arg() function.
 * @return
 *   Help text for the path.
 */
function draggableviews_help($path, $arg) {
  $output = '';
  switch ($path) {
    case "admin/help#draggableviews":
      $output = '<p>'. t("Makes views draggable.") .'</p>';
      break;
  }
  return $output;
}

/**
 * Implementing hook_admin
 */
function draggableviews_admin() {
  $form['draggableviews_nmbr_values'] = array(
    '#type' => 'textfield',
    '#title' => t('Number values'),
    '#default_value' => variable_get('draggableviews_nmbr_values', 3),
    '#size' => 4,
    '#maxlength' => 4,
    '#description' => t('The number of draggableviews value fields that will be generated'),
    '#required' => TRUE,
    '#prefix' => 'The setting above will not take effect until the views cache gets cleared!',
  );


  return system_settings_form($form);
}

/**
 * Implementing hook_validate
 */
function draggableviews_admin_validate($form, &$form_state) {
  $value = $form_state['values']['draggableviews_nmbr_values'];
  if (!is_numeric($value) OR $value < 0) {
    drupal_set_message('Invalid value (not numeric, not >= 0)', 'error');
  }
}

/**
 * Implementing hook_menu
 */
function draggableviews_menu() {
  $items = array();
  $items['admin/settings/draggableviews'] = array(
    'title' => 'Draggable views settings',
    'description' => 'Configure settings',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('draggableviews_admin'),
    'access arguments' => array('access administration pages'),
    'type' => MENU_NORMAL_ITEM,
  );
  return $items;
}

/**
 * Implementing hook_forms
 */
function draggableviews_forms() {
  $args = func_get_args();
  $form_id = $args[0];
  if (strpos($form_id, "draggableviews_view_draggabletable_form") === 0) {
    $forms[$form_id] = array(
      'callback' => 'draggableviews_view_draggabletable_form',
    );
  }
  return $forms;
}

/**
 * Build the form
 */
function draggableviews_view_draggabletable_form($form_state, $view) {
  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Save'),
  );
  $form['#submit'][] = 'draggableviews_view_draggabletable_form_submit';
  $form['#redirect'] = array('path' => $_GET['q'], 'query' => 'page='. $view->view->draggableviews_info['pager']['current_page']);
  return $form;
}

/**
 * Implement hook_theme
 */
function draggableviews_theme() {
  $array = array();
  $array['draggableviews_ui_style_plugin_draggabletable'] = array(
    'arguments' => array('form' => NULL),
  );

  $array['draggableviews_view_draggabletable_form_new'] = array(
    'template' => 'draggableviews-view-draggabletable-form',
    'preprocess functions' => array(
      'template_preprocess_draggableviews_view_draggabletable_form',
    ),
    'arguments' => array('form' => NULL),
  );

  // Register theme function for all views.
  $views = views_get_all_views();
  foreach ($views AS $view) {
    foreach (array_keys($view->display) AS $display_id) {
      $array['draggableviews_view_draggabletable_form_'. $view->vid .'_'. $display_id] = array(
        'template' => 'draggableviews-view-draggabletable-form',
        'preprocess functions' => array(
          'template_preprocess_draggableviews_view_draggabletable_form',
        ),
        'arguments' => array('form' => NULL),
      );
    }
  }
  return $array;
}

/**
 * Imlpementing hook_views_pre_render
 * 
 * We distinguish between two cases A and B:
 * A) Click sort was used:
 *   - Renumber the results as they are returned from the view. Simply use ascending numbers. (and re-execute the view).
 * 
 * B) The view is just going to be rendered.
 *   - Check the structure. If it's broken:
 *   - - Repair the structure (and re-execute the view).
 *
 * In both cases extend the visible window if paging is beeing used.
 */
function draggableviews_views_pre_render(&$view) {
  // Get info array.
  $info = _draggableviews_info($view);

  // Attach the info array to the view object,
  // so we don't have to build it again when the theme function is called.
  // We need to use a reference because the info array may change.
  $view->draggableviews_info = &$info;

  if (!isset($info['order'])) {
    // Nothing to do.
    return;
  }

  if (!is_numeric($view->vid)) {
    // The view hasn't been saved yet. Can't do anything.
    return;
  }

  if ($_GET['order']) {
    // CASE A) Click sort was used. Assign order values manually.
    _draggableviews_click_sort($info);
    // Try to extend the visible window with the suggested values. The calculated range will be returned.
    $range = _draggableviews_extend_view_window($info);
  }
  else {
    // CASE B) Check structure.
    global $pager_page_array, $pager_total, $pager_total_items;
    // Views pager use global variables which are going to be changed in order when we
    // extend the visible window. As we don't want to change the pager status we backup these values now and
    // restore them after completing all page related operations.
    $backup_pager_page_array  = $pager_page_array;
    $backup_pager_total       = $pager_total;
    $backup_pager_total_items = $pager_total_items;
    // We'll later need the original pager settings for redirecting and in case of a rebuild.
    $info['pager']            = $info['view']->pager;

    // Try to extend the visible window with the suggested values. The calculated range will be returned.
    $range = _draggableviews_extend_view_window($info);

    if (!_draggableviews_quick_check_structure($info)) {
      // The structure is broken and has to be repaired. We restore the original page settings now because
      // the current settings are based on a broken structure.
      $info['view']->pager = $info['pager'];

      _draggableviews_rebuild_hierarchy($info);
      // Try to extend the visible window with the suggested values. The calculated range will be returned.
      $range = _draggableviews_extend_view_window($info);

      drupal_set_message('The structure was broken. It has been repaired.');
    }

    // Restore global views pager variables.
    $pager_page_array  = $backup_pager_page_array;
    $pager_total       = $backup_pager_total;
    $pager_total_items = $backup_pager_total_items;
    // Restore use_pager that was set to FALSE when calling view->set_items_per_page(0).
    $info['view']->pager['use_pager'] = $info['pager']['use_pager'];
  }

  // Calculate depth values. These values will be used for theming.
  _draggableviews_calculate_depths($info);

  // Finally we set the selectable options of the order fields.
  for ($i = 0; $i < count($info['order']['fields']); $i++) {
    $info['order']['fields'][$i]['handler']->set_range($range['first_index'], $range['last_index']);
  }
}

/**
 * Implementing hook_submit
 */
function draggableviews_view_draggabletable_form_submit($vars) {
  // Check permissions.
  if (!user_access('Allow Reordering')) {
    drupal_set_message(t('You are not allowed to reorder nodes.'), 'error');
    return;
  }

  // Gather all needed information.
  $view    = $vars['#parameters'][2]->view;
  $results = $view->result;
  $input   = $vars['submit']['#post'];
  $info    = $view->draggableviews_info;

  if (!isset($info['order'])) return;

  // Loop through all resulting nodes.
  foreach ($results AS $row) {
    // set order values
    if (isset($info['order']['fields'])) {
      // The input array must have the same structure as the node array.
      // E.g. because of _draggableviews_get_hierarchy_depth(..).
      $info['input'][$row->nid]['order'][0] = $input[$info['order']['fields'][0]['field_name'] .'_'. $row->nid];
    }
    // Set parent values.
    if (isset($info['hierarchy'])) {
      $info['input'][$row->nid]['parent'] = $input[$info['hierarchy']['field']['field_name'] .'_'. $row->nid];
    }
  }

  _draggableviews_build_hierarchy($info);

  _draggableviews_save_hierarchy($info);

  if (isset($info['hierarchy'])) {
    // save expanded/collapsed states.
    global $user;

    foreach ($vars['submit']['#post'] AS $key => $val) {
      if (ereg('draggableviews_collapsed_', $key)) {
        $parent_nid = drupal_substr($key, 25);
        db_query("DELETE FROM {draggableviews_collapsed}
                  WHERE uid=%d AND parent_nid=%d",
                  $user->uid, $parent_nid);

        db_query("INSERT INTO {draggableviews_collapsed}
                  (uid, parent_nid, collapsed) VALUES (%d, %d, %d)",
                  $user->uid, $parent_nid, $val);
      }
    }
  }
}

/**
 * Discover All Implementations For Draggableviews
 *
 * @param $filter_handler
 *   The handler to return.
 *
 * @return
 *   Either the entire array with all handlers or the specified handler entry.
 */
function draggableviews_discover_handlers($filter_handler = NULL) {
  // @todo there's no cache functionality implemented yet.
  $cache = array();
  // Get implementation definitions from all modules.
  foreach (module_implements('draggableviews_handlers') as $module) {
    $function = $module .'_draggableviews_handlers';
    $result = $function();
    if (!is_array($result)) {
      continue;
    }

    $path = drupal_get_path('module', $module);

    foreach ($result as $handler => $def) {
      if (!isset($def['path'])) {
        $def['path'] = $path;
      }
      if (!isset($def['file'])) {
        $def['file'] = "$handler.inc";
      }
      if (!isset($def['handler'])) {
        $def['handler'] = 'draggableviews_handler_'. $handler;
      }
      // Merge the new data.
      $cache[$handler] = $def;
    }
  }
  
  if (isset($filter_handler)) {
    if (isset($cache[$filter_handler])) {
      return $cache[$filter_handler];
    }
    else {
      return FALSE;
    }
  }
  return $cache;
}

/**
 * Get Handlers List
 *
 * @return
 *   A list of all draggableviews handlers.
 */
function draggableviews_get_handlers_list() {
  $handlers = draggableviews_discover_handlers();
  foreach ($handlers as $handler => $def) {
    $list[$handler] = $def['title'];
  }
  return $list;
}

/**
 * Implementing hook_draggableviews_handlers
 */
function draggableviews_draggableviews_handlers() {
  return array(
    'native' => array(
      'file' => 'implementations/draggableviews_handler_native.inc',
      'title' => t('Native'),
      'description' => 'Storage of structure done by draggableviews',
      'handler' => 'draggableviews_handler_native',
    ),
  );
}

/**
 * Implementing hook_perm
 */
function draggableviews_perm() {
  return array('Allow Reordering');
}

/**
 * Impleneting hook_views_api
 */
function draggableviews_views_api() {
  return array(
    'api' => 2.0,
    'path' => drupal_get_path('module', 'draggableviews') .'/views',
  );
}