/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package org.mozilla.gecko.annotationProcessors.utils;

import java.lang.reflect.Constructor;

import java.lang.reflect.Field;

import java.lang.reflect.Member;

import java.lang.reflect.Method;

import java.util.Comparator;

public class AlphabeticAnnotatableEntityComparator<T extends Member> implements Comparator<T> {

    @Override

    public int compare(T aLhs, T aRhs) {

        // Constructors, Methods, Fields.

        boolean lIsConstructor = aLhs instanceof Constructor;

        boolean rIsConstructor = aRhs instanceof Constructor;

        boolean lIsMethod = aLhs instanceof Method;

        boolean rIsField = aRhs instanceof Field;

        if (lIsConstructor) {

            if (!rIsConstructor) {

                return -1;

            }

        } else if (lIsMethod) {

            if (rIsConstructor) {

                return 1;

            } else if (rIsField) {

                return -1;

            }

        } else {

            if (!rIsField) {

                return 1;

            }

        }

        // Verify these objects are the same type and cast them.

        if (aLhs instanceof Method) {

            return compare((Method) aLhs, (Method) aRhs);

        } else if (aLhs instanceof Field) {

            return compare((Field) aLhs, (Field) aRhs);

        } else {

            return compare((Constructor) aLhs, (Constructor) aRhs);

        }

    }

    // Alas, the type system fails us.

    private static int compare(Method aLhs, Method aRhs) {

        // Initially, attempt to differentiate the methods be name alone..

        String lName = aLhs.getName();

        String rName = aRhs.getName();

        int ret = lName.compareTo(rName);

        if (ret != 0) {

            return ret;

        }

        // The names were the same, so we need to compare signatures to find their uniqueness..

        lName = Utils.getSignature(aLhs);

        rName = Utils.getSignature(aRhs);

        return lName.compareTo(rName);

    }

    private static int compare(Constructor aLhs, Constructor aRhs) {

        // The names will be the same, so we need to compare signatures to find their uniqueness..

        String lName = Utils.getSignature(aLhs);

        String rName = Utils.getSignature(aRhs);

        return lName.compareTo(rName);

    }

    private static int compare(Field aLhs, Field aRhs) {

        // Compare field names..

        String lName = aLhs.getName();

        String rName = aRhs.getName();

        return lName.compareTo(rName);

    }

}