/*
 * Verrückte Turing-Maschinen — A turing complete game
 * Copyright (C) 2016 Christian Fraß <vidofnir@folksprak.org>
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

module lib_hashmap
	{
		
		/**
		 * @author kcf <vidofnir@folksprak.org>
		 */
		export type typ_hashmap<typ_schluessel, typ_wert> =
			{
				hashfunction : (schluessel : typ_schluessel)=>string;
				speicher : {[hashwert : string] : {schluessel : typ_schluessel; wert : typ_wert;}};
			}
		;
		
		
		/**
		 * @author kcf <vidofnir@folksprak.org>
		 */
		export function erstellen<typ_schluessel, typ_wert>
			(
				hashfunction : (schluessel : typ_schluessel)=>string
			)
			: typ_hashmap<typ_schluessel, typ_wert>
			{
				return {
					"hashfunction": hashfunction,
					"speicher": {},
				};
			}
		
		
		/**
		 * @author kcf <vidofnir@folksprak.org>
		 */
		export function setzen<typ_schluessel, typ_wert>
			(
				hashmap : typ_hashmap<typ_schluessel, typ_wert>,
				schluessel : typ_schluessel,
				wert : typ_wert
			)
			: void
			{
				let hashwert : string = hashmap.hashfunction(schluessel);
				hashmap.speicher[hashwert] = {"schluessel": schluessel, "wert": wert};
			}
		
		
		/**
		 * @author kcf <vidofnir@folksprak.org>
		 */
		export function holen<typ_schluessel, typ_wert>
			(
				hashmap : typ_hashmap<typ_schluessel, typ_wert>,
				schluessel : typ_schluessel
			)
			: lib_fehlermonade.typ_fehlermonade<typ_wert>
			{
				let hashwert : string = hashmap.hashfunction(schluessel);
				if (hashwert in hashmap.speicher)
					{
						let wert : typ_wert = hashmap.speicher[hashwert].wert;
						return (lib_fehlermonade.erstellen_schlicht<typ_wert>(wert));
					}
				else
					{
						return (lib_fehlermonade.erstellen_nichts<typ_wert>());
					}
			}
		
		
		/**
		 * @author kcf <vidofnir@folksprak.org>
		 */
		export function iterieren<typ_schluessel, typ_wert>
			(
				hashmap : typ_hashmap<typ_schluessel, typ_wert>,
				prozedur : (schluessel ?: typ_schluessel, wert ?: typ_wert)=>void
			)
			: void
			{
				Object.keys(hashmap.speicher).forEach
					(
						(hashwert) =>
							{
								let paar : {schluessel : typ_schluessel; wert : typ_wert;} = hashmap.speicher[hashwert];
								prozedur(paar.schluessel, paar.wert);
							}
					)
				;
			}
		
	}