Ads - module

gistfile1.aw

<?php

/**
 * @file turner_ads.module
 *
 * This module provides:
 *   - a configurable block for 1 ad
 *   - a block displaying a random ad
 *   - 2  image presets: ad_rectangle and ad_skyscraper
 *   - an admin screen to select which content type and field to use
 */

/**
 * Implements hook_perm().
 */
function turner_ads_perm() {
  return array('administer Turner ads');
}

/**
 * Implements hook_menu().
 */
function turner_ads_menu() {
  $items = array();
  $items['admin/settings/turner/ads'] = array(
    'title' => 'Turner Ad System settings',
    'description' => 'Settings The Turner Ad System',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('turner_ads_admin_settings'),
    'access arguments' => array('administer Turner ads'),
    'type' => MENU_NORMAL_ITEM,
  );
  return $items;
}

/**
 * An administrative form for our module.
 */
function turner_ads_admin_settings() {
  $form = array();

  // Add the content type radio button list
  $form['turner_ads_content_type'] = array(
    '#type' => 'radios',
    '#title' => t('Ad Content type'),
    '#description' => t('Select which content type will serve as advertisement.'),
    '#options' => _turner_ads_list_content_types(),
    '#default_value' => variable_get('turner_ads_content_type', 0),
    '#weight' => '-100',
  );  

  // Add the imagecache preset select list for rectangle ads
  $form['turner_ads_preset_rectangle'] = array(
    '#type' => 'select',
    '#title' => t('Imagecache preset for rectangle ads'),
    '#description' => t('Select which imagecache preset to use for rectangle ads.'),
    '#options' => _turner_ads_list_imagecache_presets(),
    '#default_value' => variable_get('turner_ads_preset_rectangle', 0),
    '#weight' => '-50',
  );

  // exercise: preset select list for skyscraper ads goes here
 
  // end exercise
 
 return system_settings_form($form);
}

/**
 * Implements hook_imagecache_default_presets().
 */
function turner_ads_imagecache_default_presets() {
  $presets = array();
  $presets['turner_ad_rectangle'] = array (
    'presetname' => 'Turner Ad - rectangle',
    'actions' =>
    array (
      0 =>
      array (
        'weight' => '0',
        'module' => 'imagecache',
        'action' => 'imagecache_scale_and_crop',
        'data' =>
        array (
          'width' => '100',
          'height' => '50',
        ),
      ),
    ),
  );

  $presets['turner_ad_skyscraper'] = array (
    'presetname' => 'Turner Ad - skyscraper',
    'actions' =>
    array (
      0 =>
      array (
        'weight' => '0',
        'module' => 'imagecache',
        'action' => 'imagecache_scale_and_crop',
        'data' =>
        array (
          'width' => '100',
          'height' => '400',
        ),
      ),
    ),
  );

  return $presets;
}

/**
 * Implements hook_block().
 */
function turner_ads_block($op = 'list', $delta = '', $edit = array()) {
  switch ($op) {
    case 'list':
      $blocks['turner_ads_rectangle'] = array(
        'info' => t('Turner Ad: rectangle'),
      );

      $blocks['turner_ads_skyscraper'] = array(
        'info' => t('Turner Ad - skyscraper'),
      );
 
      return $blocks;

    case 'configure':
      $form = array();
      if ($delta == 'turner_ads_skyscraper') {
        $form['turner_ads_skyscraper_node_id'] = array(
          '#type' => 'select',
          '#title' => t('Skyscraper ad node'),
          '#description' => t('The node which contains the image to use for the skyscraper ad'),
          '#options' => _turner_ads_skyscraper_node_list(),
          '#default_value' => variable_get('turner_ads_skyscraper_node_id', 0),
        );
      }
      return $form;

    case 'save':
      if ($delta == 'turner_ads_skyscraper') {
        variable_set('turner_ads_skyscraper_node_id', $edit['turner_ads_skyscraper_node_id']);
      }
      return;

    case 'view':
      switch ($delta) {
        case 'turner_ads_rectangle':
          $block['subject'] = '<none>';
          $block['content'] = turner_ads_block_contents($delta);
          break;

        // exercise: do the same for skyscraper ads here

        // end exercise

      }
      return $block;
  }
}

function turner_ads_block_contents($delta) {
  switch ($delta) {
    case 'turner_ads_rectangle':
      // fetch all appropriate nodes
      $term = _turner_ads_get_term('rectangle');
      $result = taxonomy_select_nodes(array($term->tid));
      $node_ids = array();
      while ($record = db_fetch_object($result)) {
        array_push($node_ids, $record->nid);
      }

      // randomize the list of nids
      $random_array_key = array_rand($node_ids);
      
      // load the node that contains our ad image
      $nid = $node_ids[$random_array_key];
      $node = node_load($nid);

      // generate the image output
      $preset = variable_get('turner_ads_preset_rectangle', '');
      $path = $node->field_ad_picture[0]['filepath'];
      $link = $node->field_ad_link[0]['value'];
      
      // fetch imagecache preset to use for rectangle ad
      if (module_exists('imagecache') && ($preset)) {
        $img = theme('imagecache', $preset, $path);
      } else {
        // use normal theme image
        $img = theme('image', $path);
      }

      $output = l($img, $link, array('html' => TRUE));
      return $output;

    case 'turner_ads_skyscraper':
      // fetch the nid from the node selected in the skyscraper block admin form
      $skyscraper_nid = variable_get('turner_ads_skyscraper_node_id', 0);
      $node = node_load($skyscraper_nid);

      $preset = variable_get('turner_ads_preset_skyscraper', '');
      $path = $node->field_ad_picture[0]['filepath'];
      $link = $node->field_ad_link[0]['value'];
      
      // fetch imagecache preset to use for skyscraper ad
      if (module_exists('imagecache') && ($preset)) {
        $img = theme('imagecache', $preset, $path);
      } else {
        // use normal theme image
        $img = theme('image', $path);
      }

      $output = l($img, $link, array('html' => TRUE));
      return $output;
  }
}

/**
 * Helper function that lists all the currently defined content types.
 *
 * Returns: array.
 */
function _turner_ads_list_content_types() {
  // see the Drupal API docs for more info on node_get_types().
  $list = node_get_types();

  // we have a list of content type objects but we're really only
  // interested in their name. As it happens the machine name of 
  // the content types is used as the key for the array, so we can
  // just use the list of the array's keys as our options list.
  return array_keys($list);
}

/**
 * Helper function that lists all the currently defined imagecache presets.
 *
 * Returns: array.
 */
function _turner_ads_list_imagecache_presets() {
  $list = array();
  if (module_exists('imagecache')) {
    $presets = imagecache_presets();
    $preset_names = array_keys($presets);
    foreach ($preset_names as $preset_name) {
      $list[$preset_name] = $preset_name;  
    }
  }
  return $list;
}

/**
 * Helper function that lists all nodes of the content type chosen
 * in the Turner Ads admin settings form.
 *
 * Returns: array.
 */
function _turner_ads_skyscraper_node_list() {
  $list = array();
  $term = _turner_ads_get_term('skyscraper');
  // fetch all nodes cateforized with the skyscraper term
  $result = taxonomy_select_nodes(array($term->tid));
  if ($result->num_rows > 0) {
    // prepare a nicely formatted list of nodes to return to the listbox field
    while ($record = db_fetch_object($result)) {
      $list[$record->nid] = $record->title; 
    }
  }
  return $list;
}

/**
 * Helper function that returns the first term object that matches the name
 *
 * Returns: array.
 */
function _turner_ads_get_term($name) {
  $terms = taxonomy_get_term_by_name($name);
  return $terms[0];
}