/*
 * FindBugs - Find Bugs in Java programs
 * Copyright (C) 2003-2007 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.classfile.analysis;

import java.lang.annotation.ElementType;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

import javax.annotation.CheckForNull;

import org.apache.bcel.Constants;
import org.objectweb.asm.Opcodes;

import edu.umd.cs.findbugs.ba.ComparableField;
import edu.umd.cs.findbugs.ba.SignatureParser;
import edu.umd.cs.findbugs.ba.XClass;
import edu.umd.cs.findbugs.ba.XFactory;
import edu.umd.cs.findbugs.ba.XField;
import edu.umd.cs.findbugs.ba.jsr305.TypeQualifierApplications;
import edu.umd.cs.findbugs.classfile.CheckedAnalysisException;
import edu.umd.cs.findbugs.classfile.ClassDescriptor;
import edu.umd.cs.findbugs.classfile.DescriptorFactory;
import edu.umd.cs.findbugs.classfile.FieldDescriptor;
import edu.umd.cs.findbugs.classfile.FieldOrMethodDescriptor;
import edu.umd.cs.findbugs.classfile.Global;
import edu.umd.cs.findbugs.internalAnnotations.DottedClassName;
import edu.umd.cs.findbugs.internalAnnotations.SlashedClassName;
import edu.umd.cs.findbugs.util.ClassName;
import edu.umd.cs.findbugs.util.Util;

/**
 * @author pugh
 */
public class FieldInfo extends FieldDescriptor implements XField {

    public static final FieldInfo[] EMPTY_ARRAY = new FieldInfo[0];

    static public class Builder {
        final int accessFlags;

        final String className, fieldName, fieldSignature;

        String fieldSourceSignature;

        final Map<ClassDescriptor, AnnotationValue> fieldAnnotations = new HashMap<ClassDescriptor, AnnotationValue>(3);

        public Builder(@SlashedClassName String className, String fieldName, String fieldSignature, int accessFlags) {
            this.className = className;
            this.fieldName = fieldName;
            this.fieldSignature = fieldSignature;
            this.accessFlags = accessFlags;
        }

        public void setSourceSignature(String fieldSourceSignature) {
            this.fieldSourceSignature = fieldSourceSignature;
        }

        public void addAnnotation(String name, AnnotationValue value) {
            ClassDescriptor annotationClass = DescriptorFactory.createClassDescriptorFromSignature(name);
            fieldAnnotations.put(annotationClass, value);
        }

        public FieldInfo build() {
            return new FieldInfo(className, fieldName, fieldSignature, fieldSourceSignature, accessFlags, fieldAnnotations, true);
        }
    }

    final int accessFlags;

    final @CheckForNull
    String fieldSourceSignature;

    Map<ClassDescriptor, AnnotationValue> fieldAnnotations;

    final boolean isResolved;


    private FieldInfo(@SlashedClassName String className, String fieldName, String fieldSignature,
            @CheckForNull String fieldSourceSignature, int accessFlags, Map<ClassDescriptor, AnnotationValue> fieldAnnotations,
            boolean isResolved) {
        super(className, fieldName, fieldSignature, (accessFlags & Constants.ACC_STATIC) != 0);
        this.accessFlags = accessFlags | (fieldName.startsWith("this$") ? Constants.ACC_FINAL : 0);
        this.fieldSourceSignature = fieldSourceSignature;
        this.fieldAnnotations = Util.immutableMap(fieldAnnotations);
        this.isResolved = isResolved;
    }

    public int getNumParams() {
        return new SignatureParser(getSignature()).getNumParameters();
    }

    private boolean checkFlag(int flag) {
        return (accessFlags & flag) != 0;
    }

    public boolean isNative() {
        return checkFlag(Constants.ACC_NATIVE);
    }

    public boolean isSynchronized() {
        return checkFlag(Constants.ACC_SYNCHRONIZED);
    }

    public boolean isDeprecated() {
        return checkFlag(Opcodes.ACC_DEPRECATED);
    }

    public @DottedClassName
    String getClassName() {
        return getClassDescriptor().toDottedClassName();
    }

    public @DottedClassName
    String getPackageName() {
        return getClassDescriptor().getPackageName();
    }

    public String getSourceSignature() {
        return fieldSourceSignature;
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Comparable#compareTo(java.lang.Object)
     */
    @Override
    public int compareTo(ComparableField rhs) {
        if (rhs instanceof FieldDescriptor) {
            return FieldOrMethodDescriptor.compareTo(this, (FieldDescriptor) rhs);
        }

        if (rhs instanceof XField) {
            return XFactory.compare((XField) this, (XField) rhs);
        }

        throw new ClassCastException("Can't compare a " + this.getClass().getName() + " to a " + rhs.getClass().getName());
    }

    /*
     * (non-Javadoc)
     * 
     * @see edu.umd.cs.findbugs.ba.AccessibleEntity#getAccessFlags()
     */
    public int getAccessFlags() {
        return accessFlags;
    }

    /*
     * (non-Javadoc)
     * 
     * @see edu.umd.cs.findbugs.ba.AccessibleEntity#isFinal()
     */
    public boolean isFinal() {
        return checkFlag(Constants.ACC_FINAL);
    }

    /*
     * (non-Javadoc)
     * 
     * @see edu.umd.cs.findbugs.ba.AccessibleEntity#isPrivate()
     */
    public boolean isPrivate() {
        return checkFlag(Constants.ACC_PRIVATE);
    }

    /*
     * (non-Javadoc)
     * 
     * @see edu.umd.cs.findbugs.ba.AccessibleEntity#isProtected()
     */
    public boolean isProtected() {
        return checkFlag(Constants.ACC_PROTECTED);
    }

    /*
     * (non-Javadoc)
     * 
     * @see edu.umd.cs.findbugs.ba.AccessibleEntity#isPublic()
     */
    public boolean isPublic() {
        return checkFlag(Constants.ACC_PUBLIC);
    }

    /*
     * (non-Javadoc)
     * 
     * @see edu.umd.cs.findbugs.ba.AccessibleEntity#isResolved()
     */
    public boolean isResolved() {
        return this.isResolved;
    }

    /*
     * (non-Javadoc)
     * 
     * @see edu.umd.cs.findbugs.ba.XField#isReferenceType()
     */
    public boolean isReferenceType() {
        return getSignature().startsWith("L") || getSignature().startsWith("[");
    }

    /*
     * (non-Javadoc)
     * 
     * @see edu.umd.cs.findbugs.ba.XField#isVolatile()
     */
    public boolean isVolatile() {
        return checkFlag(Constants.ACC_VOLATILE);
    }

    public boolean isSynthetic() {
        return checkFlag(Constants.ACC_SYNTHETIC);
    }

    public Collection<ClassDescriptor> getAnnotationDescriptors() {
        return fieldAnnotations.keySet();
    }

    public AnnotationValue getAnnotation(ClassDescriptor desc) {
        return fieldAnnotations.get(desc);
    }

    public Collection<AnnotationValue> getAnnotations() {
        return fieldAnnotations.values();
    }

    /**
     * Destructively add an annotation. We do this for "built-in" annotations
     * that might not be directly evident in the code. It's not a great idea in
     * general, but we can get away with it as long as it's done early enough
     * (i.e., before anyone asks what annotations this field has.)
     * 
     * @param annotationValue
     *            an AnnotationValue representing a field annotation
     */
    public void addAnnotation(AnnotationValue annotationValue) {
        HashMap<ClassDescriptor, AnnotationValue> updatedAnnotations = new HashMap<ClassDescriptor, AnnotationValue>(
                fieldAnnotations);
        updatedAnnotations.put(annotationValue.getAnnotationClass(), annotationValue);
        fieldAnnotations = updatedAnnotations;
        TypeQualifierApplications.updateAnnotations(this);
    }

    /*
     * (non-Javadoc)
     * 
     * @see edu.umd.cs.findbugs.ba.XField#getFieldDescriptor()
     */
    public FieldDescriptor getFieldDescriptor() {
        return this;
    }

    /**
     * Create a FieldInfo object to represent an unresolved field.
     * <em>Don't call this directly - use XFactory instead.</em>
     * 
     * @param className
     *            name of class containing the field
     * @param name
     *            name of field
     * @param signature
     *            field signature
     * @param isStatic
     *            true if field is static, false otherwise
     * @return FieldInfo object representing the unresolved field
     */
    public static FieldInfo createUnresolvedFieldInfo(String className, String name, String signature, boolean isStatic) {
        className = ClassName.toSlashedClassName(className);
        return new FieldInfo(className, name, signature, null, // without seeing
                                                               // the definition
                                                               // we don't know
                                                               // if it has a
                                                               // generic type
                isStatic ? Constants.ACC_STATIC : 0, new HashMap<ClassDescriptor, AnnotationValue>(), false);
    }

    public ElementType getElementType() {
        return ElementType.FIELD;
    }

    public @CheckForNull
    AnnotatedObject getContainingScope() {
        try {
            return Global.getAnalysisCache().getClassAnalysis(XClass.class, getClassDescriptor());
        } catch (CheckedAnalysisException e) {
            return null;
        }
    }
}
