/**
 * Find Security Bugs
 * Copyright (c) Philippe Arteau, All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3.0 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library.
 */
package com.h3xstream.findsecbugs.endpoint;

import edu.umd.cs.findbugs.BugInstance;
import edu.umd.cs.findbugs.BugReporter;
import edu.umd.cs.findbugs.Detector;
import edu.umd.cs.findbugs.Priorities;
import edu.umd.cs.findbugs.ba.ClassContext;
import org.apache.bcel.classfile.Constant;
import org.apache.bcel.classfile.ConstantPool;
import org.apache.bcel.classfile.ConstantUtf8;
import org.apache.bcel.classfile.JavaClass;

/**
 * Identify endpoints using the web framework Tapestry.
 * <p>
 * <a href="http://tapestry.apache.org/">Official Website</a>
 */
public class TapestryEndpointDetector implements Detector {

    private static final String TAPESTRY_ENDPOINT_TYPE = "TAPESTRY_ENDPOINT";

    private BugReporter bugReporter;

    public TapestryEndpointDetector(BugReporter bugReporter) {
        this.bugReporter = bugReporter;
    }

    @Override
    public void visitClassContext(ClassContext classContext) {

        JavaClass javaClass = classContext.getJavaClass();

        if (!javaClass.getPackageName().contains(".pages")) {
            return;
        }

        //The package contains ".pages" and has some references to tapestry
        // then it must be an endpoint.
        //The constants pool contains all references that are reused in the bytecode
        // including full class name and interface name.
        if (javaClass.getPackageName().contains(".pages")) {
            ConstantPool constants = javaClass.getConstantPool();
            for (Constant c : constants.getConstantPool()) {
                if (c instanceof ConstantUtf8) {
                    ConstantUtf8 utf8 = (ConstantUtf8) c;
                    String constantValue = String.valueOf(utf8.getBytes());
                    if (constantValue.startsWith("Lorg/apache/tapestry5/annotations")) {
                        bugReporter.reportBug(new BugInstance(this, TAPESTRY_ENDPOINT_TYPE, Priorities.LOW_PRIORITY) //
                                .addClass(javaClass));
                        return;
                    }
                }
            }
        }

    }

    @Override
    public void report() {

    }

}