/* -*- Mode: IDL; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is the Mozilla browser.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications, Inc.
 * Portions created by the Initial Developer are Copyright (C) 1999
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Travis Bogard <travis@netscape.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#include "nsISupports.idl"

interface nsIDocShellTreeOwner;


/**
 * The nsIDocShellTreeItem supplies the methods that are required of any item
 * that wishes to be able to live within the docshell tree either as a middle
 * node or a leaf. 
 */

[scriptable, uuid(7d935d63-6d2a-4600-afb5-9a4f7d68b825)]
interface nsIDocShellTreeItem : nsISupports
{
	/*
	name of the DocShellTreeItem
	*/
	attribute wstring name;

        /**
         * Compares the provided name against the item's name and
         * returns the appropriate result.
         *
         * @return <CODE>PR_TRUE</CODE> if names match;
         *         <CODE>PR_FALSE</CODE> otherwise.
         */
        boolean nameEquals(in wstring name);

	/*
	Definitions for the item types.
	*/
	const long typeChrome=0;            // typeChrome must equal 0
	const long typeContent=1;           // typeContent must equal 1
	const long typeContentWrapper=2;    // typeContentWrapper must equal 2
	const long typeChromeWrapper=3;     // typeChromeWrapper must equal 3

	const long typeAll=0x7FFFFFFF;

	/*
	The type this item is.  
	*/
	attribute long itemType;

	/*
	Parent DocShell.
	*/
	readonly attribute nsIDocShellTreeItem parent;

	/*
	This is call returns the same thing parent does however if the parent is
	of a different itemType, it will instead return nsnull.  This call is a
	convience function for those wishing to not cross the boundaries at which
	item types change.
	*/
	readonly attribute nsIDocShellTreeItem sameTypeParent;

	/*
	Returns the root DocShellTreeItem.  This is a convience equivalent to 
	getting the parent and its parent until there isn't a parent.
	*/
	readonly attribute nsIDocShellTreeItem rootTreeItem;

	/*
	Returns the root DocShellTreeItem of the same type.  This is a convience 
	equivalent to getting the parent of the same type and its parent until 
	there isn't a parent.
	*/
	readonly attribute nsIDocShellTreeItem sameTypeRootTreeItem;

	/*
	Returns the docShellTreeItem with the specified name.  Search order is as 
	follows...
	1.)  Check name of self, if it matches return it.
	2.)  For each immediate child.
		a.) Check name of child and if it matches return it.
		b.)  Ask the child to perform the check
			i.) Do not ask a child if it is the aRequestor
			ii.) Do not ask a child if it is of a different item type.
	3.)  If there is a parent of the same item type ask parent to perform the check
		a.) Do not ask parent if it is the aRequestor
	4.)  If there is a tree owner ask the tree owner to perform the check
		a.)  Do not ask the tree owner if it is the aRequestor
		b.)  This should only be done if there is no parent of the same type.

	Return the child DocShellTreeItem with the specified name.
	name - This is the name of the item that is trying to be found.
	aRequestor - This is the object that is requesting the find.  This
		parameter is used to identify when the child is asking its parent to find
		a child with the specific name.  The parent uses this parameter to ensure
		a resursive state does not occur by not again asking the requestor to find
		a shell by the specified name.  Inversely the child uses it to ensure it
		does not ask its parent to do the search if its parent is the one that
		asked it to search.  Children also use this to test against the treeOwner;
	aOriginalRequestor - The original treeitem that made the request, if any.
		This is used to ensure that we don't run into cross-site issues.
	*/
	nsIDocShellTreeItem findItemWithName(in wstring name,
	                                     in nsISupports aRequestor,
	                                     in nsIDocShellTreeItem aOriginalRequestor);

	/*
	The owner of the DocShell Tree.  This interface will be called upon when
	the docshell has things it needs to tell to the owner of the docshell.
	Note that docShell tree ownership does not cross tree types.  Meaning
	setting ownership on a chrome tree does not set ownership on the content 
	sub-trees.  A given tree's boundaries are identified by the type changes.
	Trees of different types may be connected, but should not be traversed
	for things such as ownership.
	
	Note implementers of this interface should NOT effect the lifetime of the 
	parent DocShell by holding this reference as it creates a cycle.  Owners
	when releasing this interface should set the treeOwner to nsnull.
	Implementers of this interface are guaranteed that when treeOwner is
	set that the poitner is valid without having to addref.
	
	Further note however when others try to get the interface it should be 
	addref'd before handing it to them. 
	*/
	readonly attribute nsIDocShellTreeOwner treeOwner;
	[noscript] void setTreeOwner(in nsIDocShellTreeOwner treeOwner);

	/* The offset of yourself in your parent's child list */
	attribute long childOffset;
};

