/*

 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package jdk.nashorn.api.tree;

/**

 * A simple implementation of the TreeVisitor for ECMAScript edition 5.1.

 *

 * <p>The visit methods corresponding to ES 5.1 language constructs walk the

 * "components" of the given tree by calling accept method passing the

 * current visitor and the additional parameter.

 *

 * <p>For constructs introduced in later versions, {@code visitUnknown}

 * is called instead which throws {@link UnknownTreeException}.

 *

 * <p> Methods in this class may be overridden subject to their

 * general contract.  Note that annotating methods in concrete

 * subclasses with {@link java.lang.Override @Override} will help

 * ensure that methods are overridden as intended.

 *

 * @param <R> the return type of this visitor's methods.  Use {@link

 *            Void} for visitors that do not need to return results.

 * @param <P> the type of the additional parameter to this visitor's

 *            methods.  Use {@code Void} for visitors that do not need an

 *            additional parameter.

 */

public class SimpleTreeVisitorES5_1<R, P> implements TreeVisitor<R, P> {

    @Override

    public R visitAssignment(final AssignmentTree node, final P r) {

        node.getVariable().accept(this, r);

        node.getExpression().accept(this, r);

        return null;

    }

    @Override

    public R visitCompoundAssignment(final CompoundAssignmentTree node, final P r) {

        node.getVariable().accept(this, r);

        node.getExpression().accept(this, r);

        return null;

    }

    @Override

    public R visitBinary(final BinaryTree node, final P r) {

        node.getLeftOperand().accept(this, r);

        node.getRightOperand().accept(this, r);

        return null;

    }

    @Override

    public R visitBlock(final BlockTree node, final P r) {

        node.getStatements().forEach((tree) -> {

            tree.accept(this, r);

        });

        return null;

    }

    @Override

    public R visitBreak(final BreakTree node, final P r) {

        return null;

    }

    @Override

    public R visitCase(final CaseTree node, final P r) {

        final Tree caseVal = node.getExpression();

        if (caseVal != null) {

            caseVal.accept(this, r);

        }

        node.getStatements().forEach((tree) -> {

            tree.accept(this, r);

        });

        return null;

    }

    @Override

    public R visitCatch(final CatchTree node, final P r) {

        final Tree cond = node.getCondition();

        if (cond != null) {

            cond.accept(this, r);

        }

        node.getParameter().accept(this, r);

        node.getBlock().accept(this, r);

        return null;

    }

    @Override

    public R visitConditionalExpression(final ConditionalExpressionTree node, final P r) {

        node.getCondition().accept(this, r);

        node.getTrueExpression().accept(this, r);

        node.getFalseExpression().accept(this, r);

        return null;

    }

    @Override

    public R visitContinue(final ContinueTree node, final P r) {

        return null;

    }

    @Override

    public R visitDebugger(final DebuggerTree node, final P r) {

        return null;

    }

    @Override

    public R visitDoWhileLoop(final DoWhileLoopTree node, final P r) {

        node.getStatement().accept(this, r);

        node.getCondition().accept(this, r);

        return null;

    }

    @Override

    public R visitErroneous(final ErroneousTree node, final P r) {

        return null;

    }

    @Override

    public R visitExpressionStatement(final ExpressionStatementTree node, final P r) {

        node.getExpression().accept(this, r);

        return null;

    }

    @Override

    public R visitForLoop(final ForLoopTree node, final P r) {

        final Tree init = node.getInitializer();

        if (init != null) {

            init.accept(this, r);

        }

        final Tree cond = node.getCondition();

        if (cond != null) {

            cond.accept(this, r);

        }

        final Tree update = node.getUpdate();

        if (update != null) {

            update.accept(this, r);

        }

        node.getStatement().accept(this, r);

        return null;

    }

    @Override

    public R visitForInLoop(final ForInLoopTree node, final P r) {

        node.getVariable().accept(this, r);

        node.getExpression().accept(this, r);

        final StatementTree stat = node.getStatement();

        if (stat != null) {

            stat.accept(this, r);

        }

        return null;

    }

    @Override

    public R visitFunctionCall(final FunctionCallTree node, final P r) {

        node.getFunctionSelect().accept(this, r);

        node.getArguments().forEach((tree) -> {

            tree.accept(this, r);

        });

        return null;

    }

    @Override

    public R visitFunctionDeclaration(final FunctionDeclarationTree node, final P r) {

        node.getParameters().forEach((tree) -> {

            tree.accept(this, r);

        });

        node.getBody().accept(this, r);

        return null;

    }

    @Override

    public R visitFunctionExpression(final FunctionExpressionTree node, final P r) {

        node.getParameters().forEach((tree) -> {

            tree.accept(this, r);

        });

        node.getBody().accept(this, r);

        return null;

    }

    @Override

    public R visitIdentifier(final IdentifierTree node, final P r) {

        return null;

    }

    @Override

    public R visitIf(final IfTree node, final P r) {

        node.getCondition().accept(this, r);

        node.getThenStatement().accept(this, r);

        final Tree elseStat = node.getElseStatement();

        if (elseStat != null) {

            elseStat.accept(this, r);

        }

        return null;

    }

    @Override

    public R visitArrayAccess(final ArrayAccessTree node, final P r) {

        node.getExpression().accept(this, r);

        node.getIndex().accept(this, r);

        return null;

    }

    @Override

    public R visitArrayLiteral(final ArrayLiteralTree node, final P r) {

        node.getElements().stream().filter((tree) -> (tree != null)).forEach((tree) -> {

            tree.accept(this, r);

        });

        return null;

    }

    @Override

    public R visitLabeledStatement(final LabeledStatementTree node, final P r) {

        node.getStatement().accept(this, r);

        return null;

    }

    @Override

    public R visitLiteral(final LiteralTree node, final P r) {

        return null;

    }

    @Override

    public R visitParenthesized(final ParenthesizedTree node, final P r) {

        node.getExpression().accept(this, r);

        return null;

    }

    @Override

    public R visitReturn(final ReturnTree node, final P r) {

        final Tree retExpr = node.getExpression();

        if (retExpr != null) {

            retExpr.accept(this, r);

        }

        return null;

    }

    @Override

    public R visitMemberSelect(final MemberSelectTree node, final P r) {

        node.getExpression().accept(this, r);

        return null;

    }

    @Override

    public R visitNew(final NewTree node, final P r) {

        node.getConstructorExpression().accept(this, r);

        return null;

    }

    @Override

    public R visitObjectLiteral(final ObjectLiteralTree node, final P r) {

        node.getProperties().forEach((tree) -> {

            tree.accept(this, r);

        });

        return null;

    }

    @Override

    public R visitProperty(final PropertyTree node, final P r) {

        FunctionExpressionTree getter = node.getGetter();

        if (getter != null) {

            getter.accept(this, r);

        }

        ExpressionTree key = node.getKey();

        if (key != null) {

            key.accept(this, r);

        }

        FunctionExpressionTree setter = node.getSetter();

        if (setter != null) {

            setter.accept(this, r);

        }

        ExpressionTree value = node.getValue();

        if (value != null) {

            value.accept(this, r);

        }

        return null;

    }

    @Override

    public R visitRegExpLiteral(final RegExpLiteralTree node, final P r) {

        return null;

    }

    @Override

    public R visitEmptyStatement(final EmptyStatementTree node, final P r) {

        return null;

    }

    @Override

    public R visitSwitch(final SwitchTree node, final P r) {

        node.getExpression().accept(this, r);

        node.getCases().forEach((tree) -> {

            tree.accept(this, r);

        });

        return null;

    }

    @Override

    public R visitThrow(final ThrowTree node, final P r) {

        node.getExpression().accept(this, r);

        return null;

    }

    @Override

    public R visitCompilationUnit(final CompilationUnitTree node, final P r) {

        node.getSourceElements().forEach((tree) -> {

            tree.accept(this, r);

        });

        return null;

    }

    @Override

    public R visitTry(final TryTree node, final P r) {

        node.getBlock().accept(this, r);

        node.getCatches().forEach((tree) -> {

            tree.accept(this, r);

        });

        final Tree finallyBlock = node.getFinallyBlock();

        if (finallyBlock != null) {

            finallyBlock.accept(this, r);

        }

        return null;

    }

    @Override

    public R visitInstanceOf(final InstanceOfTree node, final P r) {

        node.getType().accept(this, r);

        node.getExpression().accept(this, r);

        return null;

    }

    @Override

    public R visitUnary(final UnaryTree node, final P r) {

        node.getExpression().accept(this, r);

        return null;

    }

    @Override

    public R visitVariable(final VariableTree node, final P r) {

        if (node.getInitializer() != null) {

            node.getInitializer().accept(this, r);

        }

        return null;

    }

    @Override

    public R visitWhileLoop(final WhileLoopTree node, final P r) {

        node.getCondition().accept(this, r);

        node.getStatement().accept(this, r);

        return null;

    }

    @Override

    public R visitWith(final WithTree node, final P r) {

        node.getScope().accept(this, r);

        node.getStatement().accept(this, r);

        return null;

    }

    @Override