[%

# page.trail tracks path to the current page.
DEFAULT page.trail = [ ];

# List of menu items we're constructing.
map.items = [ ];

# Walk through item names in map.menu.
FOREACH id IN map.menu;
    # Fetch page from map.page.
    THROW map "Invalid menu item in $map.name: $id"
	UNLESS (item = map.page.$id);

    # Add location data.
    item.id   = id;
    item.path = path ? "$path/$id" : id;
    UNLESS item.file;
    item.file = item.page
	      ? "${item.path}/index.html"
	      : "${item.path}.html";
    END;
    item.url  = "$site.url.root$item.file";

    # Is this item on the path to the current page?
    item.hot  = page.file.match("^(../)?$item.path/index.html\$")
                || page.file.match("^(../)?${item.path}.html\$")
                || page.file.match("^(../)?${item.path}/");
    item.subs = item.hot and item.menu;
    item.here = (item.file == page.file);

    # Set next/last if this is the actual page.
    IF item.here;
	page.prev = map.page.${loop.prev};
	page.next = map.page.${loop.next};
    END;

    # Add item to map items list.
    map.items.push(item);

    # Also to the trail if the page is hot.
    page.trail.push(item) IF item.hot;

    # Expand any submenu for this item.
    IF item.subs;
	INCLUDE config/expand
	    map  = item
	    path = item.path;
    END;
END;

-%]