// Copyright 2019 yuzu emulator team
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.

#include <tuple>
#include <utility>

#include "common/assert.h"
#include "common/common_types.h"
#include "common/logging/log.h"
#include "core/core_timing.h"
#include "core/hle/ipc_helpers.h"
#include "core/hle/kernel/hle_ipc.h"
#include "core/hle/kernel/k_client_port.h"
#include "core/hle/kernel/k_handle_table.h"
#include "core/hle/kernel/k_process.h"
#include "core/hle/kernel/k_scheduler.h"
#include "core/hle/kernel/k_server_session.h"
#include "core/hle/kernel/k_session.h"
#include "core/hle/kernel/k_thread.h"
#include "core/hle/kernel/kernel.h"
#include "core/memory.h"

namespace Kernel {

KServerSession::KServerSession(KernelCore& kernel) : KSynchronizationObject{kernel} {}

KServerSession::~KServerSession() {
    kernel.ReleaseServiceThread(service_thread);
}

void KServerSession::Initialize(KSession* parent_, std::string&& name_) {
    // Set member variables.
    parent = parent_;
    name = std::move(name_);
    service_thread = kernel.CreateServiceThread(name);
}

void KServerSession::Destroy() {
    parent->OnServerClosed();

    parent->Close();
}

void KServerSession::OnClientClosed() {
    // We keep a shared pointer to the hle handler to keep it alive throughout
    // the call to ClientDisconnected, as ClientDisconnected invalidates the
    // hle_handler member itself during the course of the function executing.
    std::shared_ptr<SessionRequestHandler> handler = hle_handler;
    if (handler) {
        // Note that after this returns, this server session's hle_handler is
        // invalidated (set to null).
        handler->ClientDisconnected(this);
    }
}

bool KServerSession::IsSignaled() const {
    ASSERT(kernel.GlobalSchedulerContext().IsLocked());

    // If the client is closed, we're always signaled.
    if (parent->IsClientClosed()) {
        return true;
    }

    // Otherwise, we're signaled if we have a request and aren't handling one.
    return false;
}

void KServerSession::AppendDomainRequestHandler(std::shared_ptr<SessionRequestHandler> handler) {
    domain_request_handlers.push_back(std::move(handler));
}

std::size_t KServerSession::NumDomainRequestHandlers() const {
    return domain_request_handlers.size();
}

ResultCode KServerSession::HandleDomainSyncRequest(Kernel::HLERequestContext& context) {
    if (!context.HasDomainMessageHeader()) {
        return RESULT_SUCCESS;
    }

    // Set domain handlers in HLE context, used for domain objects (IPC interfaces) as inputs
    context.SetDomainRequestHandlers(domain_request_handlers);

    // If there is a DomainMessageHeader, then this is CommandType "Request"
    const auto& domain_message_header = context.GetDomainMessageHeader();
    const u32 object_id{domain_message_header.object_id};
    switch (domain_message_header.command) {
    case IPC::DomainMessageHeader::CommandType::SendMessage:
        if (object_id > domain_request_handlers.size()) {
            LOG_CRITICAL(IPC,
                         "object_id {} is too big! This probably means a recent service call "
                         "to {} needed to return a new interface!",
                         object_id, name);
            UNREACHABLE();
            return RESULT_SUCCESS; // Ignore error if asserts are off
        }
        return domain_request_handlers[object_id - 1]->HandleSyncRequest(context);

    case IPC::DomainMessageHeader::CommandType::CloseVirtualHandle: {
        LOG_DEBUG(IPC, "CloseVirtualHandle, object_id=0x{:08X}", object_id);

        domain_request_handlers[object_id - 1] = nullptr;

        IPC::ResponseBuilder rb{context, 2};
        rb.Push(RESULT_SUCCESS);
        return RESULT_SUCCESS;
    }
    }

    LOG_CRITICAL(IPC, "Unknown domain command={}", domain_message_header.command.Value());
    ASSERT(false);
    return RESULT_SUCCESS;
}

ResultCode KServerSession::QueueSyncRequest(KThread* thread, Core::Memory::Memory& memory) {
    u32* cmd_buf{reinterpret_cast<u32*>(memory.GetPointer(thread->GetTLSAddress()))};
    auto context = std::make_shared<HLERequestContext>(kernel, memory, this, thread);

    context->PopulateFromIncomingCommandBuffer(kernel.CurrentProcess()->GetHandleTable(), cmd_buf);

    if (auto strong_ptr = service_thread.lock()) {
        strong_ptr->QueueSyncRequest(*parent, std::move(context));
        return RESULT_SUCCESS;
    }

    return RESULT_SUCCESS;
}

ResultCode KServerSession::CompleteSyncRequest(HLERequestContext& context) {
    ResultCode result = RESULT_SUCCESS;
    // If the session has been converted to a domain, handle the domain request
    if (IsDomain() && context.HasDomainMessageHeader()) {
        result = HandleDomainSyncRequest(context);
        // If there is no domain header, the regular session handler is used
    } else if (hle_handler != nullptr) {
        // If this ServerSession has an associated HLE handler, forward the request to it.
        result = hle_handler->HandleSyncRequest(context);
    }

    if (convert_to_domain) {
        ASSERT_MSG(IsSession(), "ServerSession is already a domain instance.");
        domain_request_handlers = {hle_handler};
        convert_to_domain = false;
    }

    // Some service requests require the thread to block
    {
        KScopedSchedulerLock lock(kernel);
        if (!context.IsThreadWaiting()) {
            context.GetThread().Wakeup();
            context.GetThread().SetSyncedObject(nullptr, result);
        }
    }

    return result;
}

ResultCode KServerSession::HandleSyncRequest(KThread* thread, Core::Memory::Memory& memory,
                                             Core::Timing::CoreTiming& core_timing) {
    return QueueSyncRequest(thread, memory);
}

} // namespace Kernel