brianoz · February 20, 2014 01:10 · Feb 20, 2014
diff --git a/class-virtualthemedpage-bc.php b/class-virtualthemedpage-bc.php
@@ -0,0 +1,273 @@
+<?php
+/*
+ * Virtual Themed Page class
+ *
+ * This class implements virtual pages for a plugin.
+ *
+ * It is designed to be included then called for each part of the plugin
+ * that wants virtual pages.
+ *
+ * It supports multiple virtual pages and content generation functions.
+ * The content functions are only called if a page matches.
+ *
+ * The class uses the theme templates and as far as I know is unique in that.
+ * It also uses child theme templates ahead of main theme templates.
+ *
+ * Example code follows class.
+ *
+ * August 2013 Brian Coogan
+ *
+ */
+
+
+
+
+// There are several virtual page classes, we want to avoid a clash!
+//
+//
+class Virtual_Themed_Pages_BC
+{
+    public $title = '';
+    public $body = '';
+    private $vpages = array();  // the main array of virtual pages
+    private $mypath = '';
+    public $blankcomments = "blank-comments.php";
+
+
+    function __construct($plugin_path = null, $blankcomments = null)
+    {
+	if (empty($plugin_path))
+	    $plugin_path = dirname(__FILE__);
+	$this->mypath = $plugin_path;
+
+	if (! empty($blankcomments))
+	    $this->blankcomments = $blankcomments;
+
+	// Virtual pages are checked in the 'parse_request' filter.
+	// This action starts everything off if we are a virtual page
+	add_action('parse_request', array(&$this, 'vtp_parse_request'));
+    }
+
+    function add($virtual_regexp, $contentfunction)
+    {
+	$this->vpages[$virtual_regexp] = $contentfunction;
+    }
+
+
+    // Check page requests for Virtual pages
+    // If we have one, call the appropriate content generation function
+    //
+    function vtp_parse_request(&$wp)
+    {
+	//global $wp;
+	if (empty($wp->query_vars['pagename']))
+	    return; // page isn't permalink
+
+	//$p = $wp->query_vars['pagename'];
+	$p = $_SERVER['REQUEST_URI'];
+
+	$matched = 0;
+	foreach ($this->vpages as $regexp => $func)
+	{
+	    if (preg_match($regexp, $p))
+	    {
+		$matched = 1;
+		break;
+	    }
+	}
+	// Do nothing if not matched
+	if (! $matched)
+	    return;
+
+	// setup hooks and filters to generate virtual movie page
+	add_action('template_redirect', array(&$this, 'template_redir'));
+	add_filter('the_posts', array(&$this, 'vtp_createdummypost'));
+
+	// we also force comments removal; a comments box at the footer of
+	// a page is rather meaningless.
+	// This requires the blank_comments.php file be provided
+	add_filter('comments_template', array(&$this, 'disable_comments'), 11);
+
+	// Call user content generation function
+	// Called last so it can remove any filters it doesn't like
+	// It should set:
+	//    $this->body   -- body of the virtual page
+	//    $this->title  -- title of the virtual page
+	//    $this->template  -- optional theme-provided template
+	//          eg: page
+	//    $this->subtemplate -- optional subtemplate (eg movie)
+	// Doco is unclear whether call by reference works for call_user_func()
+	// so using call_user_func_array() instead, where it's mentioned.
+	// See end of file for example code.
+	$this->template = $this->subtemplate = null;
+	$this->title = null;
+	unset($this->body);
+	call_user_func_array($func, array(&$this, $p));
+
+	if (! isset($this->body)) //assert
+	    wp_die("Virtual Themed Pages: must save ->body [VTP07]");
+
+	return($wp);
+    }
+
+
+    // Setup a dummy post/page 
+    // From the WP view, a post == a page
+    //
+    function vtp_createdummypost($posts)
+    {
+
+	// have to create a dummy post as otherwise many templates
+	// don't call the_content filter
+	global $wp, $wp_query;
+
+	//create a fake post intance
+	$p = new stdClass;
+	// fill $p with everything a page in the database would have
+	$p->ID = -1;
+	$p->post_author = 1;
+	$p->post_date = current_time('mysql');
+	$p->post_date_gmt =  current_time('mysql', $gmt = 1);
+	$p->post_content = $this->body;
+	$p->post_title = $this->title;
+	$p->post_excerpt = '';
+	$p->post_status = 'publish';
+	$p->ping_status = 'closed';
+	$p->post_password = '';
+	$p->post_name = 'movie_details'; // slug
+	$p->to_ping = '';
+	$p->pinged = '';
+	$p->modified = $p->post_date;
+	$p->modified_gmt = $p->post_date_gmt;
+	$p->post_content_filtered = '';
+	$p->post_parent = 0;
+	$p->guid = get_home_url('/' . $p->post_name); // use url instead?
+	$p->menu_order = 0;
+	$p->post_type = 'page';
+	$p->post_mime_type = '';
+	$p->comment_status = 'closed';
+	$p->comment_count = 0;
+	$p->filter = 'raw';
+	$p->ancestors = array(); // 3.6
+
+	// reset wp_query properties to simulate a found page
+	$wp_query->is_page = TRUE;
+	$wp_query->is_singular = TRUE;
+	$wp_query->is_home = FALSE;
+	$wp_query->is_archive = FALSE;
+	$wp_query->is_category = FALSE;
+	unset($wp_query->query['error']);
+	$wp->query = array();
+	$wp_query->query_vars['error'] = '';
+	$wp_query->is_404 = FALSE;
+
+	$wp_query->current_post = $p->ID;
+	$wp_query->found_posts = 1;
+	$wp_query->post_count = 1;
+	$wp_query->comment_count = 0;
+	// -1 for current_comment displays comment if not logged in!
+	$wp_query->current_comment = null;
+	$wp_query->is_singular = 1;
+
+	$wp_query->post = $p;
+	$wp_query->posts = array($p);
+	$wp_query->queried_object = $p;
+	$wp_query->queried_object_id = $p->ID;
+	$wp_query->current_post = $p->ID;
+	$wp_query->post_count = 1;
+
+	return array($p);
+    }
+
+
+    // Virtual Movie page - tell wordpress we are using the given
+    // template if it exists; otherwise we fall back to page.php.
+    //
+    // This func gets called before any output to browser
+    // and exits at completion.
+    //
+    function template_redir()
+    {
+	//    $this->body   -- body of the virtual page
+	//    $this->title  -- title of the virtual page
+	//    $this->template  -- optional theme-provided template eg: 'page'
+	//    $this->subtemplate -- optional subtemplate (eg movie)
+	//
+
+	if (! empty($this->template) && ! empty($this->subtemplate))
+	{
+	    // looks for in child first, then master:
+	    //    template-subtemplate.php, template.php
+	    get_template_part($this->template, $this->subtemplate);
+	}
+	elseif (! empty($this->template))
+	{
+	    // looks for in child, then master:
+	    //    template.php
+	    get_template_part($this->template);
+	}
+	elseif (! empty($this->subtemplate))
+	{
+	    // looks for in child, then master:
+	    //    template.php
+	    get_template_part($this->subtemplate);
+	}
+	else
+	{
+	    get_template_part('page');
+	}
+
+	// It would be possible to add a filter for the 'the_content' filter
+	// to detect that the body had been correctly output, and then to
+	// die if not -- this would help a lot with error diagnosis.
+
+        exit;
+    }
+
+
+    // Some templates always include comments regardless, sigh.
+    // This replaces the path of the original comments template with a
+    // empty template file which returns nothing, thus eliminating
+    // comments reliably.
+    function disable_comments($file)
+    {
+	if (file_exists($this->blankcomments))
+	   return($this->mypath.'/'.$blankcomments);
+	return($file);
+    }
+
+
+} // class
+
+
+// Example code - you'd use something very like this in a plugin
+//
+if (0)
+{
+    // require 'BC_Virtual_Themed_pages.php';
+    // this code segment requires the WordPress environment
+
+    $vp =  new Virtual_Themed_Pages_BC();
+    $vp->add('#/mypattern/unique#i', 'mytest_contentfunc');
+
+    // Example of content generating function
+    // Must set $this->body even if empty string
+    function mytest_contentfunc($v, $url)
+    {
+	// extract an id from the URL
+	$id = 'none';
+	if (preg_match('#unique/(\d+)#', $url, $m))
+	    $id = $m[1];
+	// could wp_die() if id not extracted successfully...
+
+	$v->title = "My Virtual Page Title";
+	$v->body = "Some body content for my virtual page test - id $id\n";
+	$v->template = 'page'; // optional
+	$v->subtemplate = 'billing'; // optional
+    }
+}
+
+
+
+
+// end