/*
 * FindBugs - Find Bugs in Java programs
 * Copyright (C) 2005, University of Maryland
 *
 * 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 2.1 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; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package edu.umd.cs.findbugs.detect;

import java.util.HashMap;
import java.util.Map;

import org.apache.bcel.classfile.ArrayElementValue;
import org.apache.bcel.classfile.ClassElementValue;
import org.apache.bcel.classfile.ElementValue;

import edu.umd.cs.findbugs.SystemProperties;
import edu.umd.cs.findbugs.annotations.CheckForNull;
import edu.umd.cs.findbugs.ba.AnnotationDatabase;
import edu.umd.cs.findbugs.ba.AnnotationDatabase.Target;
import edu.umd.cs.findbugs.ba.NullnessAnnotation;
import edu.umd.cs.findbugs.ba.NullnessAnnotationDatabase;
import edu.umd.cs.findbugs.ba.XFactory;
import edu.umd.cs.findbugs.ba.XMethod;
import edu.umd.cs.findbugs.ba.XMethodParameter;
import edu.umd.cs.findbugs.visitclass.AnnotationVisitor;

/**
 * Scan application classes for NonNull annotations.
 * 
 * @author David Hovemeyer
 * @author William Pugh
 */
public class BuildNonNullAnnotationDatabase extends AnnotationVisitor {
    private static final boolean DEBUG = SystemProperties.getBoolean("fnd.debug.annotation");

    private static final String DEFAULT_ANNOTATION_ANNOTATION_CLASS = "DefaultAnnotation";

    private static final Map<String, AnnotationDatabase.Target> defaultKind = new HashMap<String, AnnotationDatabase.Target>();
    static {
        defaultKind.put("", AnnotationDatabase.Target.ANY);
        defaultKind.put("ForParameters", AnnotationDatabase.Target.PARAMETER);
        defaultKind.put("ForMethods", AnnotationDatabase.Target.METHOD);
        defaultKind.put("ForFields", AnnotationDatabase.Target.FIELD);

    }

    private NullnessAnnotationDatabase database;

    public BuildNonNullAnnotationDatabase(@CheckForNull NullnessAnnotationDatabase database) {
        this.database = database;
    }

    static String lastPortion(String className) {
        int i = className.lastIndexOf(".");
        if (i < 0)
            return className;
        return className.substring(i + 1);
    }

    /*
     * * @param value
     * 
     * @param map
     * 
     * @param annotationTarget
     */
    private void handleClassElementValue(ClassElementValue value, Target annotationTarget) {
        NullnessAnnotation n = NullnessAnnotation.Parser.parse(value.getClassString());
        if (n != null)
            database.addDefaultAnnotation(annotationTarget, getDottedClassName(), n);

    }

    @Override
    public void visitAnnotation(String annotationClass, Map<String, ElementValue> map, boolean runtimeVisible) {

        if (database == null) {
            return;
        }

        NullnessAnnotation n = NullnessAnnotation.Parser.parse(annotationClass);
        annotationClass = lastPortion(annotationClass);
        if (n == null) {
            if (annotationClass.startsWith("DefaultAnnotation")) {
                annotationClass = annotationClass.substring("DefaultAnnotation".length());

                Target annotationTarget = defaultKind.get(annotationClass);
                if (annotationTarget != Target.METHOD)
                    return;

                ElementValue v = map.get("value");
                if (v instanceof ClassElementValue) {
                    handleClassElementValue((ClassElementValue) v, annotationTarget);
                } else if (v instanceof ArrayElementValue) {
                    for (ElementValue v2 : ((ArrayElementValue) v).getElementValuesArray()) {
                        if (v2 instanceof ClassElementValue)
                            handleClassElementValue((ClassElementValue) v2, annotationTarget);
                    }
                }

                return;
            }

        } else if (visitingMethod())
            database.addDirectAnnotation(XFactory.createXMethod(this), n);
        else if (visitingField())
            database.addDirectAnnotation(XFactory.createXField(this), n);

    }

    @Override
    public void visitSyntheticParameterAnnotation(int p, boolean runtimeVisible) {
        if (database == null) {
            return;
        }

        XMethod xmethod = XFactory.createXMethod(this);

        XMethodParameter xparameter = new XMethodParameter(xmethod, p);

        database.addDirectAnnotation(xparameter, NullnessAnnotation.UNKNOWN_NULLNESS);

    }

    @Override
    public void visitParameterAnnotation(int p, String annotationClass, Map<String, ElementValue> map, boolean runtimeVisible) {
        if (database == null) {
            return;
        }

        NullnessAnnotation n = NullnessAnnotation.Parser.parse(annotationClass);
        annotationClass = lastPortion(annotationClass);
        if (n == null)
            return;

        XMethod xmethod = XFactory.createXMethod(this);
        if (DEBUG) {
            System.out.println("Parameter " + p + " @" + annotationClass.substring(annotationClass.lastIndexOf('/') + 1) + " in "
                    + xmethod.toString());
        }
        XMethodParameter xparameter = new XMethodParameter(xmethod, p);

        database.addDirectAnnotation(xparameter, n);

    }

}