/*
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.ddmlib;

import java.util.Comparator;

/**
 * Holds an Allocation information.
 */
public class AllocationInfo implements IStackTraceInfo {
    private final String mAllocatedClass;
    private final int mAllocNumber;
    private final int mAllocationSize;
    private final short mThreadId;
    private final StackTraceElement[] mStackTrace;

    public static enum SortMode {
        NUMBER, SIZE, CLASS, THREAD, IN_CLASS, IN_METHOD;
    }

    public final static class AllocationSorter implements Comparator<AllocationInfo> {

        private SortMode mSortMode = SortMode.SIZE;
        private boolean mDescending = true;

        public AllocationSorter() {
        }

        public void setSortMode(SortMode mode) {
            if (mSortMode == mode) {
                mDescending = !mDescending;
            } else {
                mSortMode = mode;
            }
        }

        public SortMode getSortMode() {
            return mSortMode;
        }

        public boolean isDescending() {
            return mDescending;
        }

        public int compare(AllocationInfo o1, AllocationInfo o2) {
            int diff = 0;
            switch (mSortMode) {
                case NUMBER:
                    diff = o1.mAllocNumber - o2.mAllocNumber;
                    break;
                case SIZE:
                    // pass, since diff is init with 0, we'll use SIZE compare below
                    // as a back up anyway.
                    break;
                case CLASS:
                    diff = o1.mAllocatedClass.compareTo(o2.mAllocatedClass);
                    break;
                case THREAD:
                    diff = o1.mThreadId - o2.mThreadId;
                    break;
                case IN_CLASS:
                    String class1 = o1.getFirstTraceClassName();
                    String class2 = o2.getFirstTraceClassName();
                    diff = compareOptionalString(class1, class2);
                    break;
                case IN_METHOD:
                    String method1 = o1.getFirstTraceMethodName();
                    String method2 = o2.getFirstTraceMethodName();
                    diff = compareOptionalString(method1, method2);
                    break;
            }

            if (diff == 0) {
                // same? compare on size
                diff = o1.mAllocationSize - o2.mAllocationSize;
            }

            if (mDescending) {
                diff = -diff;
            }

            return diff;
        }

        /** compares two strings that could be null */
        private int compareOptionalString(String str1, String str2) {
            if (str1 != null) {
                if (str2 == null) {
                    return -1;
                } else {
                    return str1.compareTo(str2);
                }
            } else {
                if (str2 == null) {
                    return 0;
                } else {
                    return 1;
                }
            }
        }
    }

    /*
     * Simple constructor.
     */
    AllocationInfo(int allocNumber, String allocatedClass, int allocationSize,
        short threadId, StackTraceElement[] stackTrace) {
        mAllocNumber = allocNumber;
        mAllocatedClass = allocatedClass;
        mAllocationSize = allocationSize;
        mThreadId = threadId;
        mStackTrace = stackTrace;
    }

    /**
     * Returns the allocation number. Allocations are numbered as they happen with the most
     * recent one having the highest number
     */
    public int getAllocNumber() {
        return mAllocNumber;
    }

    /**
     * Returns the name of the allocated class.
     */
    public String getAllocatedClass() {
        return mAllocatedClass;
    }

    /**
     * Returns the size of the allocation.
     */
    public int getSize() {
        return mAllocationSize;
    }

    /**
     * Returns the id of the thread that performed the allocation.
     */
    public short getThreadId() {
        return mThreadId;
    }

    /*
     * (non-Javadoc)
     * @see com.android.ddmlib.IStackTraceInfo#getStackTrace()
     */
    public StackTraceElement[] getStackTrace() {
        return mStackTrace;
    }

    public int compareTo(AllocationInfo otherAlloc) {
        return otherAlloc.mAllocationSize - mAllocationSize;
    }

    public String getFirstTraceClassName() {
        if (mStackTrace.length > 0) {
            return mStackTrace[0].getClassName();
        }

        return null;
    }

    public String getFirstTraceMethodName() {
        if (mStackTrace.length > 0) {
            return mStackTrace[0].getMethodName();
        }

        return null;
    }

    public boolean filter(String filter, boolean fullTrace) {
        if (mAllocatedClass.toLowerCase().contains(filter)) {
            return true;
        }

        if (mStackTrace.length > 0) {
            // check the top of the stack trace always
            final int length = fullTrace ? mStackTrace.length : 1;

            for (int i = 0 ; i < length ; i++) {
                if (mStackTrace[i].getClassName().toLowerCase().contains(filter)) {
                    return true;
                }

                if (mStackTrace[i].getMethodName().toLowerCase().contains(filter)) {
                    return true;
                }
            }
        }

        return false;
    }
}
