@echo off
setlocal EnableExtensions EnableDelayedExpansion

:: =============================================================================
::  build.bat — portable build for loader (Release|x64 by default)
::
::  Usage:
::    build.bat                 Build Release x64
::    build.bat debug           Build Debug x64
::    build.bat clean           Clean intermediate + output
::    build.bat --install       If no MSVC found, install VS Build Tools (minimal)
::    build.bat --install debug Install tools then Debug build
::
::  What it needs (auto if --install):
::    - Visual Studio 2019/2022/18 Build Tools OR full VS
::      workload: Desktop development with C++  (VCTools)
::    - Windows 10/11 SDK (pulled with workload)
::
::  True zero-install is not possible: MSVC is ~1–3 GB. This script only
::  downloads the official Build Tools bootstrapper when you pass --install.
::
::  Runtime: project links STATIC CRT (/MT Release, /MTd Debug) so loader.exe
::  does NOT need vcruntime140.dll / msvcp140.dll next to it on target PCs.
::  Prefer: build.bat  (Release) for drop-and-run lab use.
:: =============================================================================

cd /d "%~dp0"
set "ROOT=%CD%"
set "SLN=%ROOT%\loader.sln"
set "CONFIG=Release"
set "PLATFORM=x64"
set "DO_INSTALL=0"
set "DO_CLEAN=0"
set "MSBUILD="
set "VSWHERE="
set "TOOLSET="
set "VSINSTALL="
set "VCVARS="

for %%A in (%*) do (
  if /I "%%~A"=="--install" set "DO_INSTALL=1"
  if /I "%%~A"=="/install"  set "DO_INSTALL=1"
  if /I "%%~A"=="install"   set "DO_INSTALL=1"
  if /I "%%~A"=="debug"     set "CONFIG=Debug"
  if /I "%%~A"=="Debug"     set "CONFIG=Debug"
  if /I "%%~A"=="release"   set "CONFIG=Release"
  if /I "%%~A"=="Release"   set "CONFIG=Release"
  if /I "%%~A"=="clean"     set "DO_CLEAN=1"
  if /I "%%~A"=="Clean"     set "DO_CLEAN=1"
)

if not exist "%SLN%" (
  echo [x] loader.sln not found in "%ROOT%"
  exit /b 1
)

echo.
echo  ============================================
echo   loader build  ^|  %CONFIG%^|%PLATFORM%
echo  ============================================
echo.

call :FindVsWhere
call :FindMsBuild
if defined MSBUILD goto :HaveToolchain

if "%DO_INSTALL%"=="1" (
  call :InstallBuildTools
  call :FindVsWhere
  call :FindMsBuild
)

if not defined MSBUILD (
  echo [x] MSBuild / C++ toolset not found.
  echo.
  echo     Install options:
  echo       1^) Re-run:  build.bat --install
  echo          ^(downloads VS Build Tools + C++ workload, needs admin + internet^)
  echo       2^) Manual:  https://visualstudio.microsoft.com/visual-cpp-build-tools/
  echo          Select "Desktop development with C++"
  echo.
  exit /b 1
)

:HaveToolchain
call :DetectToolset
echo [+] MSBuild : %MSBUILD%
if defined TOOLSET (
  echo [+] Toolset: %TOOLSET%
) else (
  echo [!] Toolset: ^(project default / auto^)
)
echo [+] Config  : %CONFIG%^|%PLATFORM%
echo.

if "%DO_CLEAN%"=="1" (
  echo [*] Cleaning...
  "%MSBUILD%" "%SLN%" /t:Clean /p:Configuration=%CONFIG% /p:Platform=%PLATFORM% /m /nologo /v:minimal
  if errorlevel 1 exit /b 1
  echo [+] Clean done.
  exit /b 0
)

set "EXTRA_PROPS="
if defined TOOLSET set "EXTRA_PROPS=/p:PlatformToolset=%TOOLSET%"

echo [*] Building...
"%MSBUILD%" "%SLN%" /t:Build /p:Configuration=%CONFIG% /p:Platform=%PLATFORM% %EXTRA_PROPS% /m /nologo /v:minimal
if errorlevel 1 (
  echo.
  echo [x] Build FAILED.
  echo     If the exe is locked: close loader.exe and rebuild.
  echo     If toolset missing: build.bat --install
  exit /b 1
)

set "OUT=%ROOT%\x64\%CONFIG%\loader.exe"
if exist "%OUT%" (
  echo.
  echo [+] SUCCESS
  echo [+] Output: %OUT%
  for %%F in ("%OUT%") do echo [+] Size  : %%~zF bytes
) else (
  echo.
  echo [!] Build reported success but "%OUT%" not found.
  echo     Check loader\x64\%CONFIG%\ or project OutDir.
)

echo.
exit /b 0

:: ---------------------------------------------------------------------------
:: Find vswhere.exe (ships with VS Installer)
:: ---------------------------------------------------------------------------
:FindVsWhere
set "VSWHERE="
if exist "%ProgramFiles(x86)%\Microsoft Visual Studio\Installer\vswhere.exe" (
  set "VSWHERE=%ProgramFiles(x86)%\Microsoft Visual Studio\Installer\vswhere.exe"
  exit /b 0
)
if exist "%ProgramFiles%\Microsoft Visual Studio\Installer\vswhere.exe" (
  set "VSWHERE=%ProgramFiles%\Microsoft Visual Studio\Installer\vswhere.exe"
)
exit /b 0

:: ---------------------------------------------------------------------------
:: Locate MSBuild that can build C++ (prefers latest with VC tools)
:: ---------------------------------------------------------------------------
:FindMsBuild
set "MSBUILD="
set "VSINSTALL="

if defined VSWHERE (
  :: Prefer install with Microsoft.VisualStudio.Component.VC.Tools.x86.x64
  for /f "usebackq delims=" %%I in (`"%VSWHERE%" -latest -products * -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationPath 2^>nul`) do (
    set "VSINSTALL=%%I"
  )
  if not defined VSINSTALL (
    for /f "usebackq delims=" %%I in (`"%VSWHERE%" -latest -products * -requires Microsoft.Component.MSBuild -property installationPath 2^>nul`) do (
      set "VSINSTALL=%%I"
    )
  )
)

if defined VSINSTALL (
  if exist "!VSINSTALL!\MSBuild\Current\Bin\amd64\MSBuild.exe" (
    set "MSBUILD=!VSINSTALL!\MSBuild\Current\Bin\amd64\MSBuild.exe"
    exit /b 0
  )
  if exist "!VSINSTALL!\MSBuild\Current\Bin\MSBuild.exe" (
    set "MSBUILD=!VSINSTALL!\MSBuild\Current\Bin\MSBuild.exe"
    exit /b 0
  )
)

:: Fallback: common fixed paths (VS 18 / 2022 / 2019 Build Tools + Community)
for %%P in (
  "%ProgramFiles%\Microsoft Visual Studio\18\BuildTools\MSBuild\Current\Bin\amd64\MSBuild.exe"
  "%ProgramFiles%\Microsoft Visual Studio\18\Community\MSBuild\Current\Bin\amd64\MSBuild.exe"
  "%ProgramFiles%\Microsoft Visual Studio\18\Professional\MSBuild\Current\Bin\amd64\MSBuild.exe"
  "%ProgramFiles%\Microsoft Visual Studio\18\Enterprise\MSBuild\Current\Bin\amd64\MSBuild.exe"
  "%ProgramFiles%\Microsoft Visual Studio\2022\BuildTools\MSBuild\Current\Bin\amd64\MSBuild.exe"
  "%ProgramFiles%\Microsoft Visual Studio\2022\Community\MSBuild\Current\Bin\amd64\MSBuild.exe"
  "%ProgramFiles%\Microsoft Visual Studio\2022\Professional\MSBuild\Current\Bin\amd64\MSBuild.exe"
  "%ProgramFiles%\Microsoft Visual Studio\2022\Enterprise\MSBuild\Current\Bin\amd64\MSBuild.exe"
  "%ProgramFiles(x86)%\Microsoft Visual Studio\2019\BuildTools\MSBuild\Current\Bin\MSBuild.exe"
  "%ProgramFiles(x86)%\Microsoft Visual Studio\2019\Community\MSBuild\Current\Bin\MSBuild.exe"
) do (
  if exist %%~P (
    set "MSBUILD=%%~P"
    exit /b 0
  )
)

:: PATH
where msbuild.exe >nul 2>&1
if not errorlevel 1 (
  for /f "delims=" %%I in ('where msbuild.exe') do (
    set "MSBUILD=%%I"
    exit /b 0
  )
)
exit /b 0

:: ---------------------------------------------------------------------------
:: Pick PlatformToolset matching installed VS (project file says v145)
:: ---------------------------------------------------------------------------
:DetectToolset
set "TOOLSET="

:: Map VS major version from vswhere when possible
if defined VSWHERE (
  for /f "usebackq delims=" %%I in (`"%VSWHERE%" -latest -products * -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationVersion 2^>nul`) do (
    set "VSVER=%%I"
  )
  if defined VSVER (
    for /f "tokens=1 delims=." %%M in ("!VSVER!") do set "VSMAJOR=%%M"
    if "!VSMAJOR!"=="18" set "TOOLSET=v145"
    if "!VSMAJOR!"=="17" set "TOOLSET=v143"
    if "!VSMAJOR!"=="16" set "TOOLSET=v142"
    if defined TOOLSET exit /b 0
  )
)

:: Fallback: MSVC folder names under the install
if defined VSINSTALL if exist "!VSINSTALL!\VC\Tools\MSVC" (
  for /f "delims=" %%V in ('dir /b /ad /o-n "!VSINSTALL!\VC\Tools\MSVC" 2^>nul') do (
    set "VER=%%V"
    set "MAJ=!VER:~0,4!"
    if "!MAJ!"=="14.5" ( set "TOOLSET=v145" & exit /b 0 )
    if "!MAJ!"=="14.4" ( set "TOOLSET=v143" & exit /b 0 )
    if "!MAJ!"=="14.3" ( set "TOOLSET=v143" & exit /b 0 )
    if "!MAJ!"=="14.2" ( set "TOOLSET=v142" & exit /b 0 )
  )
)

:: Last resort: leave empty so .vcxproj PlatformToolset is used
exit /b 0

:: ---------------------------------------------------------------------------
:: Download + install minimal VS Build Tools (C++ desktop workload)
:: ---------------------------------------------------------------------------
:InstallBuildTools
echo.
echo [!] No C++ toolchain found. Installing Visual Studio Build Tools...
echo     Workload: Desktop development with C++  (VCTools)
echo     This needs Administrator rights and internet. Size ~1.5–3 GB.
echo.

:: Prefer winget if present (cleanest)
where winget.exe >nul 2>&1
if not errorlevel 1 (
  echo [*] Trying winget install of VS 2022 Build Tools...
  winget install -e --id Microsoft.VisualStudio.2022.BuildTools --accept-package-agreements --accept-source-agreements --override "--wait --passive --add Microsoft.VisualStudio.Workload.VCTools --includeRecommended --add Microsoft.VisualStudio.Component.Windows11SDK.22621"
  if not errorlevel 1 (
    echo [+] winget install finished.
    exit /b 0
  )
  echo [!] winget install failed or cancelled — falling back to bootstrapper.
)

set "BT_DIR=%ROOT%\.build-tools"
set "BT_EXE=%BT_DIR%\vs_BuildTools.exe"
if not exist "%BT_DIR%" mkdir "%BT_DIR%"

if not exist "%BT_EXE%" (
  echo [*] Downloading VS Build Tools bootstrapper...
  :: Official ever-green bootstrapper (VS 2022 Build Tools)
  powershell -NoProfile -ExecutionPolicy Bypass -Command ^
    "try { [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; Invoke-WebRequest -Uri 'https://aka.ms/vs/17/release/vs_BuildTools.exe' -OutFile '%BT_EXE%' -UseBasicParsing } catch { Write-Error $_; exit 1 }"
  if errorlevel 1 (
    echo [x] Download failed.
    exit /b 1
  )
)

echo [*] Running installer (passive). Approve UAC if prompted...
"%BT_EXE%" --wait --passive --norestart ^
  --add Microsoft.VisualStudio.Workload.VCTools ^
  --includeRecommended ^
  --add Microsoft.VisualStudio.Component.Windows11SDK.22621

if errorlevel 1 (
  echo [x] Build Tools install failed (exit %ERRORLEVEL%).
  echo     Run this .bat as Administrator, or install manually:
  echo     https://visualstudio.microsoft.com/visual-cpp-build-tools/
  exit /b 1
)

echo [+] Build Tools install finished.
exit /b 0