/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Rhino code, released
 * May 6, 1999.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1997-1999
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Steve Yegge
 *
 * Alternatively, the contents of this file may be used under the terms of
 * the GNU General Public License Version 2 or later (the "GPL"), in which
 * case the provisions of the GPL are applicable instead of those above. If
 * you wish to allow use of your version of this file only under the terms of
 * the GPL and not to allow others to use your version of this file under the
 * MPL, indicate your decision by deleting the provisions above and replacing
 * them with the notice and other provisions required by the GPL. If you do
 * not delete the provisions above, a recipient may use your version of this
 * file under either the MPL or the GPL.
 *
 * ***** END LICENSE BLOCK ***** */

package org.mozilla.javascript.ast;

import org.mozilla.javascript.Token;

/**
 * If-else statement.  Node type is {@link Token#IF}.<p>
 *
 * <pre><i>IfStatement</i> :
 *       <b>if</b> ( Expression ) Statement <b>else</b> Statement
 *       <b>if</b> ( Expression ) Statement</pre>
 */
public class IfStatement extends AstNode {

    private AstNode condition;
    private AstNode thenPart;
    private int elsePosition = -1;
    private AstNode elsePart;
    private int lp = -1;
    private int rp = -1;

    {
        type = Token.IF;
    }

    public IfStatement() {
    }

    public IfStatement(int pos) {
        super(pos);
    }

    public IfStatement(int pos, int len) {
        super(pos, len);
    }

    /**
     * Returns if condition
     */
    public AstNode getCondition() {
        return condition;
    }

    /**
     * Sets if condition.
     * @throws IllegalArgumentException if {@code condition} is {@code null}.
     */
    public void setCondition(AstNode condition) {
        assertNotNull(condition);
        this.condition = condition;
        condition.setParent(this);
    }

    /**
     * Returns statement to execute if condition is true
     */
    public AstNode getThenPart() {
        return thenPart;
    }

    /**
     * Sets statement to execute if condition is true
     * @throws IllegalArgumentException if thenPart is {@code null}
     */
    public void setThenPart(AstNode thenPart) {
        assertNotNull(thenPart);
        this.thenPart = thenPart;
        thenPart.setParent(this);
    }

    /**
     * Returns statement to execute if condition is false
     */
    public AstNode getElsePart() {
        return elsePart;
    }

    /**
     * Sets statement to execute if condition is false
     * @param elsePart statement to execute if condition is false.
     * Can be {@code null}.
     */
    public void setElsePart(AstNode elsePart) {
        this.elsePart = elsePart;
        if (elsePart != null)
            elsePart.setParent(this);
    }

    /**
     * Returns position of "else" keyword, or -1
     */
    public int getElsePosition() {
        return elsePosition;
    }

    /**
     * Sets position of "else" keyword, -1 if not present
     */
    public void setElsePosition(int elsePosition) {
        this.elsePosition = elsePosition;
    }

    /**
     * Returns left paren offset
     */
    public int getLp() {
        return lp;
    }

    /**
     * Sets left paren offset
     */
    public void setLp(int lp) {
        this.lp = lp;
    }

    /**
     * Returns right paren position, -1 if missing
     */
    public int getRp() {
        return rp;
    }

    /**
     * Sets right paren position, -1 if missing
     */
    public void setRp(int rp) {
        this.rp = rp;
    }

    /**
     * Sets both paren positions
     */
    public void setParens(int lp, int rp) {
        this.lp = lp;
        this.rp = rp;
    }

    @Override
    public String toSource(int depth) {
        String pad = makeIndent(depth);
        StringBuilder sb = new StringBuilder(32);
        sb.append(pad);
        sb.append("if (");
        sb.append(condition.toSource(0));
        sb.append(") ");
        if (!(thenPart instanceof Block)) {
            sb.append("\n").append(makeIndent(depth));
        }
        sb.append(thenPart.toSource(depth).trim());
        if (elsePart instanceof IfStatement) {
            sb.append(" else ");
            sb.append(elsePart.toSource(depth).trim());
        } else if (elsePart != null) {
            sb.append(" else ");
            sb.append(elsePart.toSource(depth).trim());
        }
        sb.append("\n");
        return sb.toString();
    }

    /**
     * Visits this node, the condition, the then-part, and
     * if supplied, the else-part.
     */
    @Override
    public void visit(NodeVisitor v) {
        if (v.visit(this)) {
            condition.visit(v);
            thenPart.visit(v);
            if (elsePart != null) {
                elsePart.visit(v);
            }
        }
    }
}
