Using open source software to design, develop, and deploy a collaborative Web site, Part 14: The announcement module source code

                
function announcement_help($section) {
 switch ($section) {
  case 'admin/modules#description':
    return t('Enables the creation of announcement pages ' .
    'that are presented on the home page.');
  case 'node/add#announcement':
    return t('An Announcement. Use this page to add an announcement page.');
  }
}
	

                
function announcement_perm() {
  return array('create announcement', 'edit announcement');
}
	

                
function announcement_node_info() {
  return array('announcement' => array(
      'name'        => 'Announcement', 
      'description' => 'An Announcement. Use this page to add an announcement page.',
      'module'      => 'announcement'));
}
	

                
function announcement_access($op, $node) {
	global $user;
	
	if ($op == 'create') {
	    return user_access('create announcement');
	}
	else if ($op == 'view') {
	  	return user_access('access content');
	}
	else if ($op == 'update' ||  $op == 'delete') {
	  	if($user->uid == $node->uid || user_access('edit announcement')) {
	    	return true;
		}
		else {
			return false;
		}
	}
  	else {
  		return false;
  	}
}
	

                
function announcement_menu($may_cache) {
 $items = array();
    if ($may_cache) {
 $items[] = array('path'     => 'announcements/add',
   'title'    => t('Add a new Announcement'), 
   'access'   => node_access('create', 'announcement'),
   'type'     => MENU_CALLBACK,
   'callback arguments' => array('announcement'),
   'callback' => 'node_add');	
						 
   $items[] = array('path'     => 'announcements',
     'title'    => t('Announcements'),
     'access'   => user_access('access content'),
	 'type'     => MENU_CALLBACK,
	 'callback' => 'announcement_all'); 
  	}
	else {
		
   $items[] = array('path'     => 'announcements/pager',
     'title'    => t('Announcements Pager Example'),
      'access'   => user_access('administer site'),
      'type'     => MENU_CALLBACK,
      'callback' => 'announcement_pager');	
		
      if(is_numeric(arg(1))) {			
		$node = node_load(arg(1));
			
   $items[] = array('path'     => 'announcements/' . arg(1),
	  'title'    => t('View an Announcement'),
	  'access'   => node_access('view', $node),
	   'type'     => MENU_CALLBACK,
	   'callback' => 'node_page');                      
							 
	$items[] = array('path'     => 'announcements/' . arg(1) . '/view',
		'title'    => t('View an Announcement'),
	    'access'   => node_access('view', $node),
	    'type'     => MENU_CALLBACK,
		'callback' => 'node_page');                      
							 
	 $items[] = array('path'     => 'announcements/' . arg(1) . '/edit',
		 'title'    => t('Edit an Announcement'),
		  'access'   => node_access('edit', $node),
		  'type'     => MENU_CALLBACK,
		  'callback' => 'node_page');          
							 
	  $items[] = array('path'     => 'announcements/' . arg(1) . '/delete',
	       'access'   => node_access('delete', $node),
	       'type'     => MENU_CALLBACK,
	       'callback' => 'node_delete_confirm');			
		}						 
	}
	
  	return $items;
}
	

                
function announcement_pager() {
	$result = pager_query(db_rewrite_sql("SELECT n.nid, n.created FROM {node} n " .
	             "WHERE type = 'announcement' ORDER BY n.created DESC"), 
	             variable_get('default_nodes_main', 10));
	while ($announcement = db_fetch_object($result)) {
		$output .= node_view(node_load($announcement->nid), 1);
    }
    
    $output .= theme('pager', NULL, variable_get('default_nodes_main', 10));
    
    return $output;
}
	

                
function announcement_cron() {
   $queryResult = db_query("UPDATE {node} AS n INNER JOIN {announcement} AS a " .
                           "ON n.nid = a.nid SET n.status = 0 " .
                           "WHERE n.type='announcement' AND n.status = 1 AND " .
                           "a.expiration_date < %d", time());

}
	

                
function announcement_link($type, $node = NULL, $teaser = FALSE) {
global $user;
	
$links = array();

	if($type == 'node' && $node->type == 'announcement') {
	
	if(node_access('create', 'announcement')) {			
$links[] = l(t('Add'), "node/add/announcement",
	  array('title' => t('Add a new announcement')));
		}
		
	if(node_access('update', $node)) {
$links[] = l(t('Edit'), "announcements/$node->nid/edit",
		array('title' => t('Edit Announcement ') . $node->title)); 

$links[] = l(t('Delete'), "announcements/$node->nid/delete",
		array('title' => t('Delete Announcement ') . $node->title)); 
		}
	}

	return $links;
}
	

                
function announcement_settings() {
$form = array();
$form['announcement_block_max_list_count'] = array('#type' => 'textfield',
'#title'         => t('Maximum number of block announcements'),
'#default_value' => variable_get('announcement_block_max_list_count', 3),
'#description'   => t('The maximum number of items listed in the announcement block'),
'#required'      => FALSE, 
'#weight'        => 0
	);
 $form['announcement_display_classification'] = array('#type' => 'checkbox',
 '#title'         => t('Display additional announcement classification'),
 '#default_value' => variable_get('announcement_display_classification', 1),
 '#description'  => t('Insert the additional classification in the announcement modules'),
 '#required'      => FALSE, 
 '#weight'        => 0
	);
	return $form; 
}
	

                
function announcement_form(&$node) {
	
    if ($node->expiration_date == NULL) {
        $node->expiration_date = time() + (365 * 86400);
    }

    if ($node->publish_date == NULL) {
        $node->publish_date = time();
    }
	
    $form['title'] = array('#type' => 'textfield',
        '#title'         => t('Title'),
        '#default_value' => $node->title,
        '#description'   => t('Title of the announcement'),
        '#required'      => TRUE, 
        '#weight'        => 1
    );
	
    $form['publication'] = array('#type'=> 'fieldset',
        '#collapsible'   => FALSE,
        '#title'         => t('Publication dates'),
        '#weight'        => 5 
    );
	 
    $form['publication']['publish_date'] = array(
        '#prefix'        => '<div class="date_widget">',
        '#suffix'        => '</div>',
        '#type'          => 'date',
        '#title'         => t('Publication date'),
        '#default_value' => _announcement_unixtime2drupaldate($node->publish_date)
    );

    $form['publication']['expiration_date'] = array(
        '#prefix'        => '<div class="date_widget">',
        '#suffix'        => '</div>',	
        '#type'          => 'date',
        '#title'         => t('Expiration date'),
        '#default_value' => _announcement_unixtime2drupaldate($node->expiration_date)
    );
	
    $form['abstract'] = array('#type' => 'textarea',
		'#title'         => t('Abstract'),
		'#default_value' => $node->abstract,
		'#rows'          => 3,
		'#description'   => t('Short summary of the full announcement'),
		'#required'      => TRUE,
		'#weight'        => 9 
    );
	
    $form['body'] = array('#type' => 'textarea',
        '#title'         => t('Body'),
        '#default_value' => $node->body,
        '#description'   => t('Full content for the announcement which is shown ' .
                                 'with the abstract on the details page'),
        '#required'      => TRUE, 
        '#weight' => 10 
    );
	
    return $form;
}
	

                
function announcement_all() {
	
    if (user_access('edit announcement')) {
       $queryResult = db_query(
            "SELECT n.nid FROM node n INNER JOIN announcement a ON n.nid = a.nid " .
            "WHERE n.type='announcement' ORDER BY n.sticky DESC, A.publish_date DESC");
    }
    else {
        $queryResult = db_query(
            "SELECT n.nid FROM node n INNER JOIN announcement a ON n.nid = a.nid " .
            "WHERE n.type='announcement' AND a.expiration_date > %d " .
            "ORDER BY n.sticky DESC, a.publish_date DESC", date("U"));
	}
	
    $page_content = array();
    $page_content[] = "<h2 class='category'>Announcements</h2>";
    while ($announcement = db_fetch_object($queryResult)) {
        $announcement = node_load($announcement->nid);
        $announcement->url = url('announcements/' . $announcement->nid);
        $page_content[] = theme('announcement_compact', $announcement);
    }
	
    return implode('', $page_content);
}
	

                
function announcement_view(&$node, $teaser = FALSE, $page = FALSE) {
    if ($page) {
        $node->url = url('announcements/' . $node->nid);
    }
}
	

                
function announcement_validate($node) {
   if ($node) {
      $publish_date    = _announcement_drupaldate2unixtime($node->publish_date);
      $expiration_date = _announcement_drupaldate2unixtime($node->expiration_date);
      if ($publish_date >= $expiration_date) {
         form_set_error('publish_date',    
           t('The publish date of an announcement must be before its expiration date.'));
      }
   }
} 
	

                
function announcement_submit(&$node) {
    $node->publish_date    = _announcement_drupaldate2unixtime($node->publish_date);
    $node->expiration_date = _announcement_drupaldate2unixtime($node->expiration_date);
	
    $now = time();
    if($now > $node->publish_date && $now < $node->expiration_date) {
        $node->status = 1;
    }
    else {
        $node->status = 0;
    }
	
    $vocab = announcement_get_vocabulary_by_name('IBC');
    $term  = taxonomy_get_term_by_name('announcements');
    $node->taxonomy = _announcement_merge_tid($vocab->vid, 
                                              $term[0]->tid, 
                                              $node->taxonomy);
}
	

                
function announcement_get_vocabulary_by_name ($name) {
	$results = db_query('SELECT * FROM {vocabulary} WHERE name = "%s"', $name);
	if (db_num_rows($results) > 0) {
	 	return db_fetch_object($results);
	}
	else {
		return null;
	}
}
	

                
function _announcement_merge_tid($vid, $tid, $taxonomy) {
    $values = array_values($taxonomy[$vid]);     // get all tid values for vocabulary
    if (!in_array($tid, $values)) {              // if the tid is not there
        $taxonomy[] = $tid;                      // add it 
    }
    return $taxonomy;
}
	

                
function announcement_load(&$node) {
	$additions = db_fetch_object(db_query('SELECT * FROM {announcement} ' .
	                                      'WHERE nid = %d', $node->nid));
  	return $additions;
}
	

                
function announcement_insert($node) {
	db_query("INSERT INTO {announcement} (nid, abstract, publish_date, expiration_date) " .
	         "VALUES (%d, '%s', '%d', '%d')", $node->nid, $node->abstract, 
	         $node->publish_date, $node->expiration_date);
	
} 
	

                
function announcement_update($node) {
	db_query("UPDATE {announcement} SET abstract='%s', publish_date = '%s', " .
	         "expiration_date = '%s' WHERE nid = %d", $node->abstract, 
	         $node->publish_date, $node->expiration_date, $node->nid);
} 
	

                
function announcement_delete($node) {
  	db_query('DELETE FROM {announcement} WHERE nid = %d', $node->nid);
}
	

                
function announcement_block($op = 'list', $delta = 0, $edit = array()) {
    global $user;
    if ($op == 'list') {
        $blocks[0]['info'] = t('Recently updated announcements');	
        $blocks[1]["info"] = t('List nodes in the IBC vocabulary');
        return $blocks;
    }
    else if ($op == 'view')	{
        $block	= array();
        switch ($delta) {
            case 0:
                $announcement_items	= array();
                if (user_access('access content')) {
                    $q = 'SELECT N.uid,N.nid,N.title,A.publish_date,N.status '.
                         'FROM {node} N JOIN {announcement} A USING(nid) '.
                         "WHERE N.type='announcement' ".
                         'AND N.status = 1 '.
                         'AND A.publish_date < %d ' .
                         'AND A.expiration_date > %d ' .
                         'ORDER BY A.publish_date DESC ';

                    $now = time();
                    $items = variable_get('announcement_block_max_list_count', 3);
                    $announcements = db_query_range($q, $now, $now, 0, $items);
                    while (db_num_rows($announcements) > 0 and 
                           $announcement = db_fetch_object($announcements)) {	
                        $announcement_items[] = $announcement;			
                    }
                }
                $block['subject'] = t('Announcements');
                $block['content'] = theme('announcement_block_list', 
                                          $announcement_items);
                break;
            case 1:
                if (user_access("access content")) {
                    $vocabulary = announcement_get_vocabulary_by_name('IBC');
                    $block["subject"]= t('IBC');
                    $block["content"]= announcement_vocab_vert($vocabulary->vid);
                }
        }
        return $block;
    }
}
	

                
function announcement_vocab_vert($vocabulary_id, $op = NULL) {
    $tree = taxonomy_get_tree($vocabulary_id);
    foreach ($tree as $term) {
        $url = "taxonomy/term/$term->tid";
        if ($op) {
            $url .= "/$op";
        }
        $link = l(t($term->name), $url, array("title" => t($term->description)));
        $out .= _taxonomy_depth($term->depth, " ")."- $link";
        $count = taxonomy_term_count_nodes($term->tid);
        if ($count) {
            $out .= " ($count)";
            $out .= _announcement_by_terms($term->tid);
        }
        else {
            $out .= " (0)";
        }
        $out .= "<br/>";
    }
    return $out;
}
	

                
function _announcement_by_terms($tid) {
	$result = '';
	$tids   = array( $tid );
	$nodes  = taxonomy_select_nodes($tids, 'or', 0, FALSE);
	while ($r = db_fetch_object($nodes)) {
		$url = "announcements/". $r->nid;
		$result .= "
  -  " . 
		           l($r->title, $url, array("title" => t($r->title)));
	}
	return $result;
}
	

                
function announcement_nodeapi(&$node, $op) {
    switch ($op) {
        case 'update index':
            if ($node->type == 'announcement') {
                $text = ''; 
                $q = db_query(
                    'SELECT a.abstract FROM node n LEFT JOIN announcement a ON '.
                    'n.nid = a.nid WHERE n.nid = %d', $node->nid);
                if ($r = db_fetch_object($q)) {
                    $text = $r->abstract;
                }
                return $text;
            }
    }
}
	

                
function theme_announcement($announcement) {
	return '';
}

function theme_announcement_compact($announcement) {
	return '';
}

function theme_announcement_block_list($announcement_list) {
	return '';
}

function phptemplate_announcement($announcement) {
 return _theme_phptemplate_announcement($announcement, 'announcement');
}

function phptemplate_announcement_compact($announcement) {
 return _theme_phptemplate_announcement
 ($announcement, 'announcement_compact');
}

function phptemplate_announcement_block_list($announcement_list) {
 global $user;
	return _phptemplate_callback('announcement_block_list', 
	  array('announcements' => $announcement_list, 
	          'user'=> $user));	
}

function _theme_phptemplate_announcement
($announcement, $announcement_template) {
	$expired = FALSE;
	if ($announcement->expiration_date < time()) {
	$expired = TRUE;		
	}
	$variables = array(
'title'      => $announcement->title,
'body'    => $announcement->body,
'links'     => $announcement->links ? theme('links', $announcement->links) : '',
'abstract'  => $announcement->abstract,
'published' => format_date($announcement->publish_date,'custom','j M, Y'),
'expires'   => format_date($announcement->expiration_date,'custom','j M, Y'), 
'expired'  => $expired,
'node'      => $announcement
	);
return _phptemplate_callback($announcement_template, $variables);	
}
	

                
function _announcement_drupaldate2unixtime($drupal_date) {

	$year  = $drupal_date["year"];
	$month = $drupal_date["month"];
	$day   = $drupal_date["day"];
	
	return mktime(0,0,0, (int)$month, (int)$day, (int)$year);
}
	

                
function _announcement_unixtime2drupaldate($unixtime) {
    return array('day'   => format_date($unixtime, 'custom', 'j'),
                 'month' => format_date($unixtime, 'custom', 'n'),
                 'year'  => format_date($unixtime, 'custom', 'Y'));
	
}