/*
 * Copyright (C) 2017-2018 Intel Corporation
 *
 * SPDX-License-Identifier: MIT
 *
 */

#include "unit_tests/helpers/memory_management.h"
#include "gtest/gtest.h"
#include <atomic>
#include <cstdlib>
#include <cstring>
#include <cassert>
#include <exception>
#include <iostream>
#include <new>

#if defined(__linux__)
#include <cstdio>
#include <execinfo.h>
#elif defined(_WIN32)
#include <Windows.h>
#endif

namespace MemoryManagement {
size_t failingAllocation = -1;
std::atomic<size_t> numAllocations(0);
std::atomic<size_t> indexAllocation(0);
std::atomic<size_t> indexDeallocation(0);
bool logTraces = false;
int fastLeakDetectionMode = 0;

AllocationEvent eventsAllocated[maxEvents];
AllocationEvent eventsDeallocated[maxEvents];

void *fastEventsAllocated[maxEvents];
void *fastEventsDeallocated[maxEvents];
std::atomic<int> fastEventsAllocatedCount(0);
std::atomic<int> fastEventsDeallocatedCount(0);
std::atomic<int> fastLeaksDetectionMode(LeakDetectionMode::STANDARD);

size_t breakOnAllocationEvent = -1;
size_t breakOnDeallocationEvent = -1;

bool detailedAllocationLoggingActive = false;

// limit size of single allocation in ULT
const size_t maxAllowedAllocationSize = 128 * 1024 * 1024 + 4096;

static void onAllocationEvent() {
    /*
    //switch to true to turn on dillignet breakpoint setting place
    bool setBreakPointHereForLeaks = false;
    if (setBreakPointHereForLeaks) {
        if (breakOnAllocationEvent == indexAllocation.load()) {
            //set breakpoint on line below
            setBreakPointHereForLeaks = false;
        }
    }*/
}

static void onDeallocationEvent(void *) {
    /*
    //switch to true to turn on dillignet breakpoint setting place
    bool setBreakPointHereForLeaks = false;
    if (setBreakPointHereForLeaks) {
        if (breakOnDeallocationEvent == indexDeallocation.load()) {
            //set breakpoint on line below
            setBreakPointHereForLeaks = false;
        }
    }*/
}

void (*deleteCallback)(void *) = onDeallocationEvent;

template <AllocationEvent::EventType typeValid, AllocationEvent::EventType typeFail>
static void *allocate(size_t size) {
    onAllocationEvent();

    if (size > maxAllowedAllocationSize) {
        std::cerr << "WARNING: Tried to allocate " << size << " bytes but " << maxAllowedAllocationSize << " is alowed!" << std::endl;
        return nullptr;
    }

    if (!fastLeakDetectionMode) {
        return malloc(size);
    }

    void *p;

    if (detailedAllocationLoggingActive) {

        auto indexAllocation = MemoryManagement::indexAllocation.fetch_add(1);
        indexAllocation %= maxEvents;

        auto &eventAllocation = eventsAllocated[indexAllocation];
        eventAllocation.size = size;

        while ((p = malloc(size)) == nullptr) {
            eventAllocation.address = p;
            eventAllocation.event = typeFail;
            throw std::bad_alloc();
        }

        eventAllocation.address = p;
        eventAllocation.event = typeValid;
#if defined(__linux__)
        eventAllocation.frames = logTraces ? backtrace(eventAllocation.callstack, AllocationEvent::CallStackSize) : 0;
#elif defined(_WIN32)
        eventAllocation.frames = logTraces ? CaptureStackBackTrace(0, AllocationEvent::CallStackSize, eventAllocation.callstack, NULL) : 0;
#else
        eventAllocation.frames = 0;
#endif
        eventAllocation.fastLeakDetectionMode = fastLeakDetectionMode;

        numAllocations++;
    } else {
        p = malloc(size);
    }

    if (fastLeakDetectionMode && p && fastLeaksDetectionMode == LeakDetectionMode::STANDARD) {
        auto currentIndex = fastEventsAllocatedCount++;
        fastEventsAllocated[currentIndex] = p;
        assert(currentIndex <= fastEvents);
    }

    return p;
}

template <AllocationEvent::EventType typeValid, AllocationEvent::EventType typeFail>
static void *allocate(size_t size, const std::nothrow_t &) {
    onAllocationEvent();

    if (size > maxAllowedAllocationSize) {
        std::cerr << "WARNING: Tried to allocate " << size << " bytes but " << maxAllowedAllocationSize << " is alowed!" << std::endl;
        return nullptr;
    }

    if (!fastLeakDetectionMode) {
        return malloc(size);
    }

    void *p;

    if (detailedAllocationLoggingActive) {

        auto indexAllocation = MemoryManagement::indexAllocation.fetch_add(1);
        indexAllocation %= maxEvents;

        p = indexAllocation == failingAllocation
                ? nullptr
                : malloc(size);

        auto &eventAllocation = eventsAllocated[indexAllocation];
        eventAllocation.event = p
                                    ? typeValid
                                    : typeFail;
        eventAllocation.address = p;
        eventAllocation.size = size;
#if defined(__linux__)
        eventAllocation.frames = logTraces ? backtrace(eventAllocation.callstack, AllocationEvent::CallStackSize) : 0;
#elif defined(_WIN32)
        eventAllocation.frames = logTraces ? CaptureStackBackTrace(0, AllocationEvent::CallStackSize, eventAllocation.callstack, NULL) : 0;
#else
        eventAllocation.frames = 0;
#endif
        eventAllocation.fastLeakDetectionMode = fastLeakDetectionMode;
        numAllocations += p ? 1 : 0;
    } else {
        p = malloc(size);
    }

    if (fastLeakDetectionMode && p && fastLeaksDetectionMode == LeakDetectionMode::STANDARD) {
        auto currentIndex = fastEventsAllocatedCount++;
        fastEventsAllocated[currentIndex] = p;
        assert(currentIndex <= fastEvents);
    }

    return p;
}

template <AllocationEvent::EventType typeValid>
static void deallocate(void *p) {
    deleteCallback(p);

    if (!fastLeakDetectionMode) {
        if (p) {
            free(p);
        }
        return;
    }

    if (p) {
        if (detailedAllocationLoggingActive) {

            auto indexDeallocation = MemoryManagement::indexDeallocation.fetch_add(1);
            indexDeallocation %= maxEvents;

            --numAllocations;

            auto &eventDeallocation = eventsDeallocated[indexDeallocation];
            eventDeallocation.event = typeValid;
            eventDeallocation.address = p;
            eventDeallocation.size = -1;
#if defined(__linux__)
            eventDeallocation.frames = logTraces ? backtrace(eventDeallocation.callstack, AllocationEvent::CallStackSize) : 0;
#elif defined(_WIN32)
            eventDeallocation.frames = logTraces ? CaptureStackBackTrace(0, AllocationEvent::CallStackSize, eventDeallocation.callstack, NULL) : 0;
#else
            eventDeallocation.frames = 0;
#endif
            eventDeallocation.fastLeakDetectionMode = fastLeakDetectionMode;
        }
        free(p);

        if (fastLeakDetectionMode && p && fastLeaksDetectionMode == LeakDetectionMode::STANDARD) {
            auto currentIndex = fastEventsDeallocatedCount++;
            fastEventsDeallocated[currentIndex] = p;
            assert(currentIndex <= fastEvents);
        }
    }
}
int detectLeaks() {
    int indexLeak = -1;

    for (int allocationIndex = 0u; allocationIndex < fastEventsAllocatedCount; allocationIndex++) {
        auto &eventAllocation = fastEventsAllocated[allocationIndex];
        int deallocationIndex = 0u;
        for (; deallocationIndex < fastEventsDeallocatedCount; deallocationIndex++) {
            if (fastEventsDeallocated[deallocationIndex] == nullptr) {
                continue;
            }
            if (fastEventsDeallocated[deallocationIndex] == eventAllocation) {
                fastEventsDeallocated[deallocationIndex] = nullptr;
                break;
            }
        }
        if (deallocationIndex == fastEventsDeallocatedCount) {
            indexLeak = allocationIndex;
            break;
        }
    }
    return indexLeak;
}
} // namespace MemoryManagement

using MemoryManagement::allocate;
using MemoryManagement::AllocationEvent;
using MemoryManagement::deallocate;

#if defined(_WIN32)
#pragma warning(disable : 4290)
#endif
void *operator new(size_t size) {
    return allocate<AllocationEvent::EVENT_NEW, AllocationEvent::EVENT_NEW_FAIL>(size);
}

void *operator new(size_t size, const std::nothrow_t &) noexcept {
    return allocate<AllocationEvent::EVENT_NEW_NOTHROW, AllocationEvent::EVENT_NEW_NOTHROW_FAIL>(size, std::nothrow);
}

void *operator new[](size_t size) {
    return allocate<AllocationEvent::EVENT_NEW_ARRAY, AllocationEvent::EVENT_NEW_ARRAY_FAIL>(size);
}

void *operator new[](size_t size, const std::nothrow_t &t) noexcept {
    return allocate<AllocationEvent::EVENT_NEW_ARRAY_NOTHROW, AllocationEvent::EVENT_NEW_ARRAY_NOTHROW_FAIL>(size, std::nothrow);
}

void operator delete(void *p) noexcept {
    deallocate<AllocationEvent::EVENT_DELETE>(p);
}

void operator delete[](void *p) noexcept {
    deallocate<AllocationEvent::EVENT_DELETE_ARRAY>(p);
}
void operator delete(void *p, size_t size) noexcept {
    deallocate<AllocationEvent::EVENT_DELETE>(p);
}

void operator delete[](void *p, size_t size) noexcept {
    deallocate<AllocationEvent::EVENT_DELETE_ARRAY>(p);
}
