/*
XOWA: the XOWA Offline Wiki Application
Copyright (C) 2012 gnosygnu@gmail.com

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as
published by the Free Software Foundation, either version 3 of the
License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
package gplx.core.btries; import gplx.*; import gplx.core.*;
import gplx.intl.*;
class Btrie_utf8_itm {
	private Hash_adp_bry nxts;
	private byte[] asymmetric_bry;
	public Btrie_utf8_itm(byte[] key, Object val) {this.key = key; this.val = val;}
	public byte[] Key() {return key;} private byte[] key;
	public Object Val() {return val;} public void Val_set(Object val) {this.val = val;} private Object val;
	public boolean Nxts_is_empty() {return nxts == null;}
	public void Clear() {
		val = null;
		nxts.Clear();
		nxts = null;
	}
	public Btrie_utf8_itm Nxts_find(byte[] src, int c_bgn, int c_end, boolean called_by_match) {
		if (nxts == null) return null;
		Object rv_obj = nxts.Get_by_mid(src, c_bgn, c_end);
		if (rv_obj == null) return null;
		Btrie_utf8_itm rv = (Btrie_utf8_itm)rv_obj;
		byte[] asymmetric_bry = rv.asymmetric_bry;
		if (asymmetric_bry == null)													// itm doesn't have asymmetric_bry; note that this is the case for most items
			return rv;
		else {																		// itm has asymmetric_bry; EX: "İ" was added to trie, must match "İ" and "i"; 
			if (called_by_match) {													// called by mgr.Match
				return
					(	Bry_.Eq(rv.key, src, c_bgn, c_end)							// key matches src;				EX: "aİ"
					||	Bry_.Eq(rv.asymmetric_bry, src, c_bgn, c_end)				// asymmetric_bry matches src;	EX: "ai"; note that "aI" won't match
					)
					? rv : null;
			}
			else {																	// called by mgr.Add; this means that an asymmetric_itm was already added; happens when "İ" added first and then "I" added next
				rv.asymmetric_bry = null;											// always null out asymmetric_bry; note that this noops non-asymmetric itms, while making an asymmetric_itm case-insenstivie (matches İ,i,I); see tests
				return rv;
			}
		}
	}
	public Btrie_utf8_itm Nxts_add(Gfo_case_mgr case_mgr, byte[] key, Object val) {
		Btrie_utf8_itm rv = new Btrie_utf8_itm(key, val);
		if (nxts == null) nxts = Hash_adp_bry.ci_utf8_(case_mgr);
		nxts.Add_bry_obj(key, rv);
		Gfo_case_itm case_itm = case_mgr.Get_or_null(key[0], key, 0, key.length);	// get case_item
		if (case_itm != null) {														// note that case_itm may be null; EX: "__TOC__" and "_"
			byte[] asymmetric_bry = case_itm.Asymmetric_bry();
			if (asymmetric_bry != null) {											// case_itm has asymmetry_bry; only itms in Xol_case_itm_ that are created with Tid_upper and Tid_lower will be non-null
				rv.asymmetric_bry = asymmetric_bry;									// set itm to asymmetric_bry; EX: for İ, asymmetric_bry = i
				nxts.Add_bry_obj(asymmetric_bry, rv);								// add the asymmetric_bry to the hash; in above example, this allows "i" to match "İ"
			}
		}
		return rv;
	}
}
