/***
    Copyright (C) 2022 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: IPCMemory.NT.cpp
    Date: 2022-4-15
    Author: Reece
***/
#include <Source/RuntimeInternal.hpp>
#include "IPC.hpp"
#include "IPCHandle.hpp"
#include "IPCMemory.NT.hpp"

namespace Aurora::IO::IPC
{
    //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
    // Shared memory
    //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

    IPCSharedMemoryImpl::IPCSharedMemoryImpl(HANDLE handle, void *ptr, const IPC::IPCHandle &ipcHandle) :
        base_(ptr), len_(ipcHandle.values[0].token.word), handle_(handle), ipcHandle_(ipcHandle)
    {

    }

    IPCSharedMemoryImpl::~IPCSharedMemoryImpl()
    {
        if (this->base_)
        {
            ::UnmapViewOfFile(this->base_);
        }
        
        AuWin32CloseHandle(this->handle_);
    }

    Memory::MemoryViewWrite IPCSharedMemoryImpl::GetMemory()
    {
        return AuMemoryViewWrite(this->base_, this->len_);
    }

    AuUInt IPCSharedMemoryImpl::GetLength()
    {
        return this->len_;
    }

    AuString IPCSharedMemoryImpl::ExportToString()
    {
        return this->ipcHandle_.ToString();
    }

    AUKN_SYM AuSPtr<IPCSharedMemory>      NewSharedMemory(AuUInt length)
    {
        IPC::IPCHandle handle;
        IPC::IPCToken token;
        token.NewId();
        token.word = length;

        handle.PushId(EIPCHandleType::eIPCMemory, token);

        auto path = token.ToNTPath();
        auto file = CreateFileMappingA(INVALID_HANDLE_VALUE,
                                       nullptr,
                                       PAGE_READWRITE,
                                   #if defined(AURORA_IS_64BIT)
                                       AuBitsToHigher(length),
                                       AuBitsToLower(length),
                                   #else
                                       0,
                                       length,
                                   #endif
                                       path.c_str());

        if ((file == INVALID_HANDLE_VALUE) ||
            (!file))
        {
            return {};
        }

        auto map = ::MapViewOfFile(file,
                                   FILE_MAP_ALL_ACCESS,
                                   0,
                                   0,
                                   length);
        if (!map)
        {
            SysPushErrorIO();
            AuWin32CloseHandle(file);
            return {};
        }

        auto object = AuMakeShared<IPCSharedMemoryImpl>(file, map, handle);
        if (!object)
        {
            SysPushErrorMem();
            ::UnmapViewOfFile(map);
            AuWin32CloseHandle(file);
            return {};
        }

        return object;
    }

    AUKN_SYM AuSPtr<IPCSharedMemory>      ImportSharedMemory(const AuString &handleString)
    {
        IPC::IPCHandle handle;

        if (!handle.FromString(handleString))
        {
            SysPushErrorParseError();
            return {};
        }

        auto token = handle.GetToken(EIPCHandleType::eIPCMemory, 0);
        if (!token)
        {
            SysPushErrorParseError();
            return {};
        }

        auto length = token->token.word;
        auto path = token->token.ToNTPath();
        auto file = ::OpenFileMappingA(FILE_MAP_ALL_ACCESS,
                                       FALSE,
                                       path.c_str());

        if ((file == INVALID_HANDLE_VALUE) ||
            (!file))
        {
            return {};
        }

        auto map = ::MapViewOfFile(file,
                                   FILE_MAP_ALL_ACCESS,
                                   0,
                                   0,
                                   length);
        if (!map)
        {
            SysPushErrorIO();
            AuWin32CloseHandle(file);
            return {};
        }

        auto object = AuMakeShared<IPCSharedMemoryImpl>(file, map, handle);
        if (!object)
        {
            SysPushErrorMem();
            ::UnmapViewOfFile(map);
            AuWin32CloseHandle(file);
            return {};
        }

        return object;
    }
}