x-theme.php

<?php

/**
 * Wrapper for theme() that takes the override theme name to render this hook in.
 */
function _x_theme($hook, $vars, $override_theme) {
	_x_start_theme_override($override_theme);
	$return = theme($hook, $vars);
	_x_end_theme_override();

	return $return;
}

/**
 * Start a global theme override. Starting now, everything theme related will use the given theme.
 */
function _x_start_theme_override($override_theme) {
	global $theme, $theme_key, $theme_info, $theme_path;
	global $original_theme;
	$original_theme = $theme;

	// Keep resetting the static theme registry cache...
	$registry = &drupal_static('theme_get_registry');

	_x_drupal_theme_reinitialize($override_theme);
	$registry = NULL;
}

/**
 * End the global theme override: back to the original theme.
 */
function _x_end_theme_override() {
	global $original_theme;
	if (!$original_theme) {
		return;
	}

	global $theme, $theme_key, $theme_info, $theme_path;

	// Keep resetting the static theme registry cache...
	$registry = &drupal_static('theme_get_registry');

	_x_drupal_theme_reinitialize($original_theme);
	$registry = NULL;

	$original_theme = NULL;
}

/**
 * Do as little as possible of a theme initialize (no collecting JS/CSS).
 */
function _x_drupal_theme_reinitialize($theme) {
	$themes = list_themes();

	// Find all our ancestor themes and put them in an array.
	$base_theme = array();
	$ancestor = $theme;
	while ($ancestor && isset($themes[$ancestor]->base_theme)) {
		$ancestor = $themes[$ancestor]->base_theme;
		$base_theme[] = $themes[$ancestor];
	}

	$theme = $themes[$theme];

	global $theme_info, $base_theme_info, $theme_engine, $theme_path;
	$theme_info = $theme;
	$base_theme_info = $base_theme;

	$theme_path = dirname($theme->filename);

	$GLOBALS['theme'] = $GLOBALS['theme_key'] = $theme->name;

	$theme_engine = NULL;

	// Initialize the theme.
	if (isset($theme->engine)) {
		// Include the engine.
		include_once DRUPAL_ROOT . '/' . $theme->owner;

		$theme_engine = $theme->engine;
		if (function_exists($theme_engine . '_init')) {
			foreach ($base_theme as $base) {
				call_user_func($theme_engine . '_init', $base);
			}
			call_user_func($theme_engine . '_init', $theme);
		}
	}
	else {
		// include non-engine theme files
		foreach ($base_theme as $base) {
			// Include the theme file or the engine.
			if (!empty($base->owner)) {
				include_once DRUPAL_ROOT . '/' . $base->owner;
			}
		}
		// and our theme gets one too.
		if (!empty($theme->owner)) {
			include_once DRUPAL_ROOT . '/' . $theme->owner;
		}
	}

	_theme_registry_callback('_theme_load_registry', array($theme, $base_theme, $theme_engine));
}