#include "FFPlatform_private.h"
#include "common/io.h"
#include "common/library.h"
#include "common/mallocHelper.h"
#include "common/stringUtils.h"
#include "common/windows/unicode.h"
#include "common/windows/registry.h"
#include "common/windows/nt.h"

#include <windows.h>
#include <shlobj.h>
#include <sddl.h>

#define SECURITY_WIN32 1 // For secext.h
#include <secext.h>

static void getExePath(FFPlatform* platform)
{
    wchar_t exePathW[MAX_PATH];
    DWORD exePathWLen = GetModuleFileNameW(NULL, exePathW, MAX_PATH);
    if (exePathWLen == 0 || exePathWLen >= MAX_PATH) return;

    FF_AUTO_CLOSE_FD HANDLE hPath = CreateFileW(exePathW, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
    if (hPath != INVALID_HANDLE_VALUE)
    {
        DWORD len = GetFinalPathNameByHandleW(hPath, exePathW, MAX_PATH, FILE_NAME_OPENED);
        if (len > 0 && len < MAX_PATH)
            exePathWLen = len;
    }

    ffStrbufSetNWS(&platform->exePath, exePathWLen, exePathW);
    if (ffStrbufStartsWithS(&platform->exePath, "\\\\?\\"))
        ffStrbufSubstrAfter(&platform->exePath, 3);
    ffStrbufReplaceAllC(&platform->exePath, '\\', '/');
}

static void getHomeDir(FFPlatform* platform)
{
    PWSTR pPath = NULL;
    if(SUCCEEDED(SHGetKnownFolderPath(&FOLDERID_Profile, KF_FLAG_DEFAULT, NULL, &pPath)))
    {
        ffStrbufSetWS(&platform->homeDir, pPath);
        ffStrbufReplaceAllC(&platform->homeDir, '\\', '/');
        ffStrbufEnsureEndsWithC(&platform->homeDir, '/');
    }
    else
    {
        ffStrbufSetS(&platform->homeDir, getenv("USERPROFILE"));
        ffStrbufReplaceAllC(&platform->homeDir, '\\', '/');
        ffStrbufEnsureEndsWithC(&platform->homeDir, '/');
    }
    CoTaskMemFree(pPath);
}

static void getCacheDir(FFPlatform* platform)
{
    PWSTR pPath = NULL;
    if(SUCCEEDED(SHGetKnownFolderPath(&FOLDERID_LocalAppData, KF_FLAG_DEFAULT, NULL, &pPath)))
    {
        ffStrbufSetWS(&platform->cacheDir, pPath);
        ffStrbufReplaceAllC(&platform->cacheDir, '\\', '/');
        ffStrbufEnsureEndsWithC(&platform->cacheDir, '/');
    }
    else
    {
        ffStrbufAppend(&platform->cacheDir, &platform->homeDir);
        ffStrbufAppendS(&platform->cacheDir, "AppData/Local/");
    }
    CoTaskMemFree(pPath);
}

static void platformPathAddKnownFolder(FFlist* dirs, REFKNOWNFOLDERID folderId)
{
    PWSTR pPath = NULL;
    if (SUCCEEDED(SHGetKnownFolderPath(folderId, KF_FLAG_DEFAULT, NULL, &pPath)))
    {
        FF_STRBUF_AUTO_DESTROY buffer = ffStrbufCreateWS(pPath);
        CoTaskMemFree(pPath);
        ffStrbufReplaceAllC(&buffer, '\\', '/');
        ffStrbufEnsureEndsWithC(&buffer, '/');
        if (!ffListContains(dirs, &buffer, (void*) ffStrbufEqual))
            ffStrbufInitMove((FFstrbuf*) ffListAdd(dirs), &buffer);
    }
}

static void platformPathAddEnvSuffix(FFlist* dirs, const char* env, const char* suffix)
{
    const char* value = getenv(env);
    if(!ffStrSet(value))
        return;

    FF_STRBUF_AUTO_DESTROY buffer = ffStrbufCreateA(64);
    ffStrbufAppendS(&buffer, value);
    ffStrbufReplaceAllC(&buffer, '\\', '/');
    ffStrbufEnsureEndsWithC(&buffer, '/');
    if (suffix)
    {
        ffStrbufAppendS(&buffer, suffix);
        ffStrbufEnsureEndsWithC(&buffer, '/');
    }

    if (ffPathExists(buffer.chars, FF_PATHTYPE_DIRECTORY) && !ffListContains(dirs, &buffer, (void*) ffStrbufEqual))
        ffStrbufInitMove((FFstrbuf*) ffListAdd(dirs), &buffer);
}

static void getConfigDirs(FFPlatform* platform)
{
    if(getenv("MSYSTEM"))
    {
        // We are in MSYS2 / Git Bash
        platformPathAddEnvSuffix(&platform->configDirs, "HOME", ".config/");
        platformPathAddEnvSuffix(&platform->configDirs, "HOME", NULL);
        platformPathAddEnvSuffix(&platform->configDirs, "MINGW_PREFIX", "etc");
    }

    ffPlatformPathAddHome(&platform->configDirs, platform, ".config/");
    platformPathAddKnownFolder(&platform->configDirs, &FOLDERID_ProgramData);
    platformPathAddKnownFolder(&platform->configDirs, &FOLDERID_RoamingAppData);
    platformPathAddKnownFolder(&platform->configDirs, &FOLDERID_LocalAppData);
    ffPlatformPathAddHome(&platform->configDirs, platform, "");
}

static void getDataDirs(FFPlatform* platform)
{
    if(getenv("MSYSTEM") && getenv("HOME"))
    {
        // We are in MSYS2 / Git Bash
        platformPathAddEnvSuffix(&platform->dataDirs, "HOME", ".local/share/");
        platformPathAddEnvSuffix(&platform->dataDirs, "HOME", NULL);
        platformPathAddEnvSuffix(&platform->dataDirs, "MINGW_PREFIX", "share");
    }
    ffPlatformPathAddHome(&platform->dataDirs, platform, ".local/share/");
    platformPathAddKnownFolder(&platform->dataDirs, &FOLDERID_ProgramData);
    platformPathAddKnownFolder(&platform->dataDirs, &FOLDERID_RoamingAppData);
    platformPathAddKnownFolder(&platform->dataDirs, &FOLDERID_LocalAppData);
    ffPlatformPathAddHome(&platform->dataDirs, platform, "");
}

static void getUserName(FFPlatform* platform)
{
    wchar_t buffer[256];
    DWORD size = ARRAY_SIZE(buffer);
    if (GetUserNameExW(NameDisplay, buffer, &size))
        ffStrbufSetWS(&platform->fullUserName, buffer);

    size = ARRAY_SIZE(buffer);
    if (GetUserNameW(buffer, &size)) // GetUserNameExW(10002)?
    {
        ffStrbufSetWS(&platform->userName, buffer);

        size = 0;
        DWORD refDomainSize = 0;
        SID_NAME_USE sidNameUse = SidTypeUnknown;
        LookupAccountNameW(NULL, buffer, NULL, &size, NULL, &refDomainSize, &sidNameUse);
        if (size > 0)
        {
            FF_AUTO_FREE PSID sid = (PSID) malloc(size);
            FF_AUTO_FREE LPWSTR refDomain = (LPWSTR) malloc(refDomainSize * sizeof(wchar_t));
            if (LookupAccountNameW(NULL, buffer, sid, &size, refDomain, &refDomainSize, &sidNameUse))
            {
                LPWSTR sidString;
                if (ConvertSidToStringSidW(sid, &sidString))
                {
                    ffStrbufSetWS(&platform->sid, sidString);
                    LocalFree(sidString);
                }
            }
        }
    }
    else
        ffStrbufSetS(&platform->userName, getenv("USERNAME"));
}

static void getHostName(FFPlatform* platform)
{
    wchar_t buffer[256];
    DWORD len = ARRAY_SIZE(buffer);
    if (GetComputerNameExW(ComputerNameDnsHostname, buffer, &len) && len > 0)
        ffStrbufSetNWS(&platform->hostName, len, buffer);
    else
    {
        len = ARRAY_SIZE(buffer);
        if (GetComputerNameExW(ComputerNameNetBIOS, buffer, &len) && len > 0)
            ffStrbufSetNWS(&platform->hostName, len, buffer);
    }
}

static void getUserShell(FFPlatform* platform)
{
    // Works in MSYS2
    const char* userShell = getenv("SHELL");
    if (userShell)
    {
        ffStrbufAppendS(&platform->userShell, userShell);
        ffStrbufReplaceAllC(&platform->userShell, '\\', '/');
    }
}

static const char* detectWine(void)
{
    const char * __cdecl wine_get_version(void);
    HMODULE hntdll = GetModuleHandleW(L"ntdll.dll");
    if (!hntdll) return NULL;
    FF_LIBRARY_LOAD_SYMBOL_LAZY(hntdll, wine_get_version);
    if (!ffwine_get_version) return NULL;
    return ffwine_get_version();
}

static void getSystemReleaseAndVersion(FFPlatformSysinfo* info)
{
    RTL_OSVERSIONINFOW osVersion = { .dwOSVersionInfoSize = sizeof(osVersion) };
    if (!NT_SUCCESS(RtlGetVersion(&osVersion))) // From PEB, not affected by manifest shenanigans
        return;

    FF_HKEY_AUTO_DESTROY hKey = NULL;
    if(!ffRegOpenKeyForRead(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion", &hKey, NULL))
        return;

    uint32_t ubr = 0;
    ffRegReadUint(hKey, L"UBR", &ubr, NULL);

    ffStrbufAppendF(&info->release,
        "%u.%u.%u.%u",
        (unsigned) osVersion.dwMajorVersion,
        (unsigned) osVersion.dwMinorVersion,
        (unsigned) osVersion.dwBuildNumber,
        (unsigned) ubr);

    ffRegReadStrbuf(hKey, L"BuildLabEx", &info->version, NULL);

    const char* wineVersion = detectWine();
    if (wineVersion)
        ffStrbufSetF(&info->name, "Wine_%s", wineVersion);
    else
    {
        switch (osVersion.dwPlatformId) // Hardcoded as WIN32_NT, but just in case
        {
        case VER_PLATFORM_WIN32s:
            ffStrbufSetStatic(&info->name, "WIN32s");
            break;
        case VER_PLATFORM_WIN32_WINDOWS:
            ffStrbufSetStatic(&info->name, "WIN32_WINDOWS");
            break;
        case VER_PLATFORM_WIN32_NT:
            ffStrbufSetStatic(&info->name, "WIN32_NT");
            break;
        }
    }
}

static void getSystemPageSize(FFPlatformSysinfo* info)
{
    SYSTEM_BASIC_INFORMATION sbi;
    if (NT_SUCCESS(NtQuerySystemInformation(SystemBasicInformation, &sbi, sizeof(sbi), NULL)))
        info->pageSize = sbi.PhysicalPageSize;
    else
        info->pageSize = 4096;
}

static void getSystemArchitecture(FFPlatformSysinfo* info)
{
    SYSTEM_PROCESSOR_INFORMATION spi;
    if (NT_SUCCESS(NtQuerySystemInformation(SystemProcessorInformation, &spi, sizeof(spi), NULL)))
    {
        switch (spi.ProcessorArchitecture)
        {
        case PROCESSOR_ARCHITECTURE_AMD64:
            ffStrbufSetStatic(&info->architecture, "x86_64");
            break;
        case PROCESSOR_ARCHITECTURE_IA64:
            ffStrbufSetStatic(&info->architecture, "ia64");
            break;
        case PROCESSOR_ARCHITECTURE_INTEL:
            switch (spi.ProcessorLevel)
            {
                case 4:
                    ffStrbufSetStatic(&info->architecture, "i486");
                    break;
                case 5:
                    ffStrbufSetStatic(&info->architecture, "i586");
                    break;
                case 6:
                    ffStrbufSetStatic(&info->architecture, "i686");
                    break;
                default:
                    ffStrbufSetStatic(&info->architecture, "i386");
                    break;
            }
            break;
        case PROCESSOR_ARCHITECTURE_ARM64:
            ffStrbufSetStatic(&info->architecture, "aarch64");
            break;
        case PROCESSOR_ARCHITECTURE_ARM:
            ffStrbufSetStatic(&info->architecture, "arm");
            break;
        case PROCESSOR_ARCHITECTURE_PPC:
            ffStrbufSetStatic(&info->architecture, "ppc");
            break;
        case PROCESSOR_ARCHITECTURE_MIPS:
            ffStrbufSetStatic(&info->architecture, "mips");
            break;
        case PROCESSOR_ARCHITECTURE_ALPHA:
            ffStrbufSetStatic(&info->architecture, "alpha");
            break;
        case PROCESSOR_ARCHITECTURE_ALPHA64:
            ffStrbufSetStatic(&info->architecture, "alpha64");
            break;
        case PROCESSOR_ARCHITECTURE_UNKNOWN:
        default:
            ffStrbufSetStatic(&info->architecture, "unknown");
            break;
        }
    }
}

static void getCwd(FFPlatform* platform)
{
    #if _WIN64
    static_assert(
        offsetof(RTL_USER_PROCESS_PARAMETERS, Reserved2[5]) == 0x38,
        "CurrentDirectory should be at offset 0x38 in RTL_USER_PROCESS_PARAMETERS. Structure layout mismatch detected.");
    #endif
    PCURDIR cwd = (PCURDIR) &NtCurrentTeb()->ProcessEnvironmentBlock->ProcessParameters->Reserved2[5];
    ffStrbufSetNWS(&platform->cwd, cwd->DosPath.Length / sizeof(WCHAR), cwd->DosPath.Buffer);
    ffStrbufReplaceAllC(&platform->cwd, '\\', '/');
    ffStrbufEnsureEndsWithC(&platform->cwd, '/');
}

void ffPlatformInitImpl(FFPlatform* platform)
{
    platform->pid = (uint32_t) GetCurrentProcessId();
    getExePath(platform);
    getCwd(platform);
    getHomeDir(platform);
    getCacheDir(platform);
    getConfigDirs(platform);
    getDataDirs(platform);

    getUserName(platform);
    getHostName(platform);
    getUserShell(platform);

    getSystemReleaseAndVersion(&platform->sysinfo);
    getSystemArchitecture(&platform->sysinfo);
    getSystemPageSize(&platform->sysinfo);
}