param(
    [ValidateRange(1, 32)]
    [int]$Jobs = 4
)

$ErrorActionPreference = "Stop"
. (Join-Path $PSScriptRoot "native_dep_versions.ps1")

foreach ($required in @($Bash, $Make, (Join-Path $MingwBin "gcc.exe"), $FfmpegSource)) {
    if (-not (Test-Path -LiteralPath $required)) { throw "Required path not found: $required" }
}

$BuildToolsBin = Join-Path $ToolsRoot "build-bin"
New-Item -ItemType Directory -Force $FfmpegBuild, $FfmpegInstall, $BuildToolsBin | Out-Null
Copy-Item -LiteralPath $Make -Destination (Join-Path $BuildToolsBin "make.exe") -Force

function Convert-ToBashPath([string]$Path) {
    if ($Path.Contains("'")) { throw "Paths containing a single quote are not supported: $Path" }
    $result = & $Bash -lc "cygpath -u '$Path'"
    if ($LASTEXITCODE -ne 0) { throw "Cannot convert path for Git Bash: $Path" }
    return $result.Trim()
}

$SourcePosix = Convert-ToBashPath $FfmpegSource
$BuildPosix = Convert-ToBashPath $FfmpegBuild
$InstallPosix = Convert-ToBashPath $FfmpegInstall
$SourceMake = $FfmpegSource.Replace("\", "/")
$MingwBinPosix = Convert-ToBashPath $MingwBin
$BuildToolsPosix = Convert-ToBashPath $BuildToolsBin
$NasmRootPosix = Convert-ToBashPath $NasmRoot

$BuildCommand = @"
set -e
export PATH='${NasmRootPosix}:${BuildToolsPosix}:${MingwBinPosix}:/usr/bin:/bin'
cd '$BuildPosix'
if [ ! -f ffbuild/config.mak ]; then
  '$SourcePosix/configure' \
    --prefix='$InstallPosix' \
    --target-os=mingw32 \
    --arch=x86_64 \
    --cc=gcc \
    --cxx=g++ \
    --ar=ar \
    --ranlib=ranlib \
    --strip=strip \
    --windres=windres \
    --enable-shared \
    --disable-static \
    --disable-debug \
    --disable-doc \
    --disable-programs \
    --disable-avdevice \
    --disable-avformat \
    --disable-avfilter \
    --disable-swresample \
    --disable-postproc \
    --disable-network \
    --disable-everything \
    --enable-avcodec \
    --enable-avutil \
    --enable-swscale \
    --enable-decoder=h264 \
    --enable-decoder=hevc \
    --enable-decoder=mjpeg \
    --enable-parser=h264 \
    --enable-parser=hevc \
    --enable-parser=mjpeg \
    --enable-hwaccel=h264_d3d11va \
    --enable-hwaccel=hevc_d3d11va \
    --enable-hwaccel=h264_d3d11va2 \
    --enable-hwaccel=hevc_d3d11va2 \
    --enable-hwaccel=h264_dxva2 \
    --enable-hwaccel=hevc_dxva2 \
    --extra-cflags=-O2
fi
# Native mingw32-make cannot resolve Git Bash paths such as /c/source.
sed -i 's|${SourcePosix}|${SourceMake}|g' Makefile ffbuild/config.mak
make -j$Jobs
"@

& $Bash -lc $BuildCommand
if ($LASTEXITCODE -ne 0) { throw "FFmpeg build failed" }

$binDir = Join-Path $FfmpegInstall "bin"
$libDir = Join-Path $FfmpegInstall "lib"
$pkgConfigDir = Join-Path $libDir "pkgconfig"
$includeDir = Join-Path $FfmpegInstall "include"
New-Item -ItemType Directory -Force $binDir, $libDir, $pkgConfigDir, $includeDir | Out-Null

foreach ($component in @("avcodec", "avutil", "swscale")) {
    $buildComponent = Join-Path $FfmpegBuild "lib$component"
    $sourceComponent = Join-Path $FfmpegSource "lib$component"
    $includeComponent = Join-Path $includeDir "lib$component"
    New-Item -ItemType Directory -Force $includeComponent | Out-Null

    $dll = Get-ChildItem -LiteralPath $buildComponent -Filter "$component-*.dll" | Select-Object -First 1
    $importLibrary = Join-Path $buildComponent "$component.lib"
    $pkgConfig = Join-Path $buildComponent "lib$component.pc"
    foreach ($required in @($dll.FullName, $importLibrary, $pkgConfig)) {
        if (-not $required -or -not (Test-Path -LiteralPath $required)) {
            throw "FFmpeg artifact not found: $required"
        }
    }

    Copy-Item -LiteralPath $dll.FullName -Destination $binDir -Force
    Copy-Item -LiteralPath $importLibrary -Destination (Join-Path $libDir "$component.lib") -Force
    Copy-Item -LiteralPath $importLibrary -Destination (Join-Path $libDir "lib$component.dll.a") -Force
    Copy-Item -LiteralPath $pkgConfig -Destination $pkgConfigDir -Force
    Get-ChildItem -LiteralPath $sourceComponent -File -Filter "*.h" |
        Copy-Item -Destination $includeComponent -Force
    Get-ChildItem -LiteralPath $buildComponent -File -Filter "*.h" |
        Copy-Item -Destination $includeComponent -Force
}

$Avcodec = Get-ChildItem -LiteralPath $binDir -Filter "avcodec-*.dll" | Select-Object -First 1
if (-not $Avcodec) { throw "FFmpeg staging finished but avcodec DLL is missing" }
Write-Host "FFmpeg installed to $FfmpegInstall"