// SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
// SPDX-FileCopyrightText: Copyright 2010 The Android Open Source Project
// SPDX-License-Identifier: GPL-3.0-or-later
// Parts of this implementation were based on:
// https://cs.android.com/android/platform/superproject/+/android-5.1.1_r38:frameworks/native/libs/gui/ConsumerBase.cpp

#include "common/assert.h"
#include "common/logging/log.h"
#include "core/hle/service/nvnflinger/buffer_item.h"
#include "core/hle/service/nvnflinger/buffer_queue_consumer.h"
#include "core/hle/service/nvnflinger/buffer_queue_core.h"
#include "core/hle/service/nvnflinger/consumer_base.h"
#include "core/hle/service/nvnflinger/ui/graphic_buffer.h"

namespace Service::android {

ConsumerBase::ConsumerBase(std::shared_ptr<BufferQueueConsumer> consumer_)
    : consumer{std::move(consumer_)} {}

ConsumerBase::~ConsumerBase() {
    std::scoped_lock lock{mutex};

    ASSERT_MSG(is_abandoned, "consumer is not abandoned!");
}

void ConsumerBase::Connect(bool controlled_by_app) {
    consumer->Connect(shared_from_this(), controlled_by_app);
}

void ConsumerBase::Abandon() {
    LOG_DEBUG(Service_Nvnflinger, "called");

    std::scoped_lock lock{mutex};

    if (!is_abandoned) {
        this->AbandonLocked();
        is_abandoned = true;
    }
}

void ConsumerBase::AbandonLocked() {
    for (int i = 0; i < BufferQueueDefs::NUM_BUFFER_SLOTS; i++) {
        this->FreeBufferLocked(i);
    }
    // disconnect from the BufferQueue
    consumer->Disconnect();
    consumer = nullptr;
}

void ConsumerBase::FreeBufferLocked(s32 slot_index) {
    LOG_DEBUG(Service_Nvnflinger, "slot_index={}", slot_index);

    slots[slot_index].graphic_buffer = nullptr;
    slots[slot_index].fence = Fence::NoFence();
    slots[slot_index].frame_number = 0;
}

void ConsumerBase::OnFrameAvailable(const BufferItem& item) {
    LOG_DEBUG(Service_Nvnflinger, "called");
}

void ConsumerBase::OnFrameReplaced(const BufferItem& item) {
    LOG_DEBUG(Service_Nvnflinger, "called");
}

void ConsumerBase::OnBuffersReleased() {
    std::scoped_lock lock{mutex};

    LOG_DEBUG(Service_Nvnflinger, "called");

    if (is_abandoned) {
        // Nothing to do if we're already abandoned.
        return;
    }

    u64 mask = 0;
    consumer->GetReleasedBuffers(&mask);
    for (int i = 0; i < BufferQueueDefs::NUM_BUFFER_SLOTS; i++) {
        if (mask & (1ULL << i)) {
            FreeBufferLocked(i);
        }
    }
}

void ConsumerBase::OnSidebandStreamChanged() {}

Status ConsumerBase::AcquireBufferLocked(BufferItem* item, std::chrono::nanoseconds present_when) {
    Status err = consumer->AcquireBuffer(item, present_when);
    if (err != Status::NoError) {
        return err;
    }

    if (item->graphic_buffer != nullptr) {
        slots[item->slot].graphic_buffer = item->graphic_buffer;
    }

    slots[item->slot].frame_number = item->frame_number;
    slots[item->slot].fence = item->fence;

    LOG_DEBUG(Service_Nvnflinger, "slot={}", item->slot);

    return Status::NoError;
}

Status ConsumerBase::AddReleaseFenceLocked(s32 slot,
                                           const std::shared_ptr<GraphicBuffer>& graphic_buffer,
                                           const Fence& fence) {
    LOG_DEBUG(Service_Nvnflinger, "slot={}", slot);

    // If consumer no longer tracks this graphic_buffer, we can safely
    // drop this fence, as it will never be received by the producer.

    if (!StillTracking(slot, graphic_buffer)) {
        return Status::NoError;
    }

    slots[slot].fence = fence;

    return Status::NoError;
}

Status ConsumerBase::ReleaseBufferLocked(s32 slot,
                                         const std::shared_ptr<GraphicBuffer>& graphic_buffer) {
    // If consumer no longer tracks this graphic_buffer (we received a new
    // buffer on the same slot), the buffer producer is definitely no longer
    // tracking it.

    if (!StillTracking(slot, graphic_buffer)) {
        return Status::NoError;
    }

    LOG_DEBUG(Service_Nvnflinger, "slot={}", slot);
    Status err = consumer->ReleaseBuffer(slot, slots[slot].frame_number, slots[slot].fence);
    if (err == Status::StaleBufferSlot) {
        FreeBufferLocked(slot);
    }

    slots[slot].fence = Fence::NoFence();

    return err;
}

bool ConsumerBase::StillTracking(s32 slot,
                                 const std::shared_ptr<GraphicBuffer>& graphic_buffer) const {
    if (slot < 0 || slot >= BufferQueueDefs::NUM_BUFFER_SLOTS) {
        return false;
    }

    return (slots[slot].graphic_buffer != nullptr &&
            slots[slot].graphic_buffer->Handle() == graphic_buffer->Handle());
}

} // namespace Service::android
