package jcircus.complementaryenvs;

import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Set;
import java.util.Stack;

public class StackVarEnv {
	private HashMap <String, String> _map;

    public StackVarEnv () {
        this._map = new LinkedHashMap <String, String> ();
    }
    private HashMap <String, String> getMap () {
    	return this._map;
    }
    public StackVarEnv (StackVarEnv cde) {
    	this._map = new LinkedHashMap <String, String> (cde.getMap());
    }
	public void push (String varName) {
		String stackpos = this.get(varName);
		this._map.remove(varName);
		if (stackpos.equals("")) {
			this._map.put (varName, "1");
		}
		else {
			this._map.put(varName, (new Integer ((Integer.parseInt(stackpos) + 1))).toString());
		}
	}
	public void pop (String varName) {
		String stackpos = this.get(varName);
		if (stackpos.equals("1")) {
			this._map.remove (varName);
		}
		else if (stackpos.equals("")) {}
		else {
			this._map.put(varName, (new Integer ((Integer.parseInt(stackpos) - 1))).toString());
		}
	}
	public String get (String varName) {
		if (!this._map.containsKey(varName)) {
			return "";
		}
		return this._map.get(varName);
	}
	public String getPreviousScope (String varName) {
		if (this.get(varName).length() > 0) {
			return this.get(varName).substring(0, this.get(varName).length() - 1);
		}
		else {
			return "";
		}
	}
	public String getNextScope (String varName) {
		if (this.get(varName).length() > 0) {
			return this.get(varName) + "1";
		}
		else {
			return "1";
		}
	}
	public String getNewName (String varName) {
		return (varName + this.get(varName));
	}
	public boolean containsKey (String str) {
		return this._map.keySet().contains(str);
	}
	public Set <String> keySet() {
		return this._map.keySet();
	}
}