ProcedureDecl.java

package eu.wietsevenema.lang.oberon.ast.declarations;

import java.util.ArrayList;
import java.util.List;

import xtc.tree.Node;
import eu.wietsevenema.lang.oberon.ast.expressions.Identifier;
import eu.wietsevenema.lang.oberon.ast.statements.Statement;
import eu.wietsevenema.lang.oberon.ast.types.VarType;
import eu.wietsevenema.lang.oberon.ast.visitors.interpreter.DeclarationEvaluator;
import eu.wietsevenema.lang.oberon.ast.visitors.interpreter.StatementEvaluator;
import eu.wietsevenema.lang.oberon.interpreter.Formal;
import eu.wietsevenema.lang.oberon.interpreter.Procedure;
import eu.wietsevenema.lang.oberon.interpreter.InterpreterScope;

public class ProcedureDecl extends Declaration implements Procedure {

	private Identifier identifier;
	private List<FormalVar> formals;
	private Declarations declarations;
	private List<Statement> statements;

	public ProcedureDecl(Node idstart, List<Node> formals, Declarations declarations, List<Statement> statements) {
		this.identifier = (Identifier) idstart;
		this.formals = transformFormals(formals);
		this.declarations = (declarations != null) ? declarations : new Declarations(null, null, null, null);
		this.statements = (statements != null) ? statements : new ArrayList<Statement>();
	}

	public Identifier getIdentifier() {
		return identifier;
	}

	public List<FormalVar> getFormalVars() {
		return formals;
	}

	@Override
	public List<Formal> getFormals() {
		ArrayList<Formal> result = new ArrayList<Formal>();
		for (FormalVar fv : this.getFormalVars()) {
			result.add((Formal) fv);
		}
		return result;
	}

	public Declarations getDeclarations() {
		return declarations;
	}

	public List<Statement> getStatements() {
		return statements;
	}

	private List<FormalVar> transformFormals(List<Node> formals) {
		ArrayList<FormalVar> result = new ArrayList<FormalVar>();
		if (formals != null) {
			for (Node n : formals) {
				/*
				 * Node n => ("VAR":Word)? IdentList void:":":Symbol Type get(0)
				 * = ("VAR":Word)? get(1) = IdentList get(2) = Type
				 */
				// TODO refactor
				if (n.getString(0) == null) { // Normal var.
					for (Object identifier : (List<?>) n.get(1)) {
						if (!(identifier instanceof Identifier)) {
							throw new IllegalStateException();
						} else {
							result.add(new FormalVar((Identifier) identifier, (VarType) n.get(2)));
						}
					}
				} else { // Reference var.
					for (Object identifier : (List<?>) n.get(1)) {
						if (!(identifier instanceof Identifier)) {
							throw new IllegalStateException();
						} else {
							result.add(new FormalVarRef((Identifier) identifier, (VarType) n.get(2)));
						}
					}
				}
			}
		}
		return result;
	}

	@Override
	public void execute(InterpreterScope scope) {
		// Process declarations.
		DeclarationEvaluator declEval = new DeclarationEvaluator(scope);
		declEval.dispatch(this.getDeclarations());

		// Execute statements.
		StatementEvaluator statEval = new StatementEvaluator(scope);
		for (Statement s : this.getStatements()) {
			statEval.dispatch(s);
		}
	}

}