package semantic.symboltable;

import java.util.*;
import ast.definition.Definition;

public class SymbolTable {

	private int scope=0;
	private List<Map<String,Definition>> table;
	public SymbolTable()  {
		// * Creates the table of contexts
		table=new ArrayList<Map<String,Definition>>();
		// * Adds the first context
		table.add(new HashMap<String,Definition>());
	}

	public void set() {
		scope++;
		table.add(new HashMap<String,Definition>());
	}

	public void reset() {
		table.remove(scope--);
	}

	public boolean insert(Definition definition) {
		if (table.get(scope).get(definition.getName())!=null)
			return false;
		table.get(scope).put(definition.getName(), definition);
		definition.setScope(this.scope);
		return true;
	}

	public Definition find(String id) {
		for (int i=scope;i>=0;i--) {
			Definition definition=table.get(i).get(id);
			if (definition!=null)
				return definition;
		}
		return null;
	}

	public Definition findInCurrentScope(String id) {
		return table.get(scope).get(id);
	}
}