Add-Type -AssemblyName System.IO.Compression.FileSystem

function Main {
    if ($PSVersionTable.PSEdition -ne 'Desktop' -and $env:OS -ne 'Windows_NT') {
        Write-Warning "Please run it on Windows. "
        return 1
    }

    $procArch = $Env:PROCESSOR_ARCHITECTURE
    if ($procArch -eq 'x86') {
        Write-Warning "This script does not support 32-bit Windows. Exiting..."
        return 1
    }

    $flagPath = "$env:TEMP\elevation_success.flag"
    if (Test-Path $flagPath) { Remove-Item $flagPath -ErrorAction SilentlyContinue }

    # --- Elevation check ---
    $IsAdmin = ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole(
        [Security.Principal.WindowsBuiltInRole]::Administrator)

    if (-not $IsAdmin) {
        Write-Host "Elevation required. Relaunching..."
        $tempScript = [IO.Path]::ChangeExtension([IO.Path]::GetTempFileName(), ".ps1")
        Invoke-WebRequest -Uri "https://get.msvc.win/64" -OutFile $tempScript
        Start-Process powershell -Verb RunAs -ArgumentList "-NoProfile -ExecutionPolicy Bypass -File `"$tempScript`""
        Start-Sleep -Seconds 10
        if (-Not (Test-Path $flagPath)) {
            Write-Warning "User did not confirm UAC prompt or something went wrong."
            return 1
        }
        else {
            Remove-Item $flagPath -ErrorAction SilentlyContinue
            Write-Host "Setup ran successfully."
            return 0
        }
    }

    # --- Elevated section ---
    New-Item -Path $flagPath -ItemType File -Force | Out-Null
    Write-Host "Running with elevated privileges..."

    $tempDir = New-Item -ItemType Directory -Path ([IO.Path]::Combine($env:TEMP, [guid]::NewGuid().ToString()))
    $aria2Dir = Join-Path $tempDir "aria2"
    $aria2Exe = Join-Path $aria2Dir "aria2c.exe"

    # --- Check User IP location ---

    $geoInfo = Invoke-RestMethod -Uri 'https://ipapi.co/json/'
    $countryCode = $geoInfo.country

    # --- Check Proxy Settings ---
    $webProxy = [System.Net.WebRequest]::GetSystemWebProxy()
    $uri = New-Object Uri("http://example.com")
    $proxyUri = $webProxy.GetProxy($uri)

    $useProxy = $proxyUri.Host -ne "example.com"
    if ($useProxy) {
        $proxyAddress = $proxyUri.Authority
        Write-Host "Detected system proxy: $proxyAddress"
    }

    # --- Ensure aria2c is available ---
    if (-not (Test-Path $aria2Exe)) {
        Write-Host "Downloading aria2c..."
        $aria2Zip = Join-Path $tempDir "aria2.zip"
        if ($countryCode -eq 'CN') {
            $aria2Url = "https://gitee.com/HikariCalyx/OSTRemote/releases/download/v1.0/aria2-1.37.0-win-64bit-build1.zip"
            # Workaround for specific Chinese ISPs that would not resolve domains properly like aka.ms
            $regionalWorkaround = "--async-dns-server=223.5.5.5"
        }
        else {
            $aria2Url = "https://github.com/aria2/aria2/releases/download/release-1.37.0/aria2-1.37.0-win-64bit-build1.zip"
            $regionalWorkaround = ""
        }
        if ($useProxy) {
            $regionalWorkaround = "--all-proxy=$proxyAddress"
        }
        Invoke-WebRequest -Uri $aria2Url -OutFile $aria2Zip
        Expand-Archive -Path $aria2Zip -DestinationPath $aria2Dir -Force
        $found = Get-ChildItem -Path $aria2Dir -Recurse -Filter "aria2c.exe" | Select-Object -First 1
        if ($found) { Copy-Item $found.FullName -Destination $aria2Exe -Force }
    }

    # --- Define all downloads ---
    $downloads = @(
        @{ Name = "vstor_redist.exe"; Url = "https://download.microsoft.com/download/8/6/4/8641e164-7796-4b34-81c7-30d24a5bd533/vstor_redist.exe" },
        @{ Name = "vcredist_2005_x86.exe"; Url = "https://download.microsoft.com/download/8/b/4/8b42259f-5d70-43f4-ac2e-4b208fd8d66a/vcredist_x86.exe"; Year = "2005" },
        @{ Name = "vcredist_2005_x64.exe"; Url = "https://download.microsoft.com/download/8/b/4/8b42259f-5d70-43f4-ac2e-4b208fd8d66a/vcredist_x64.exe"; Year = "2005" },
        @{ Name = "vcredist_2008_x86.exe"; Url = "https://download.microsoft.com/download/5/D/8/5D8C65CB-C849-4025-8E95-C3966CAFD8AE/vcredist_x86.exe"; Year = "2008" },
        @{ Name = "vcredist_2008_x64.exe"; Url = "https://download.microsoft.com/download/5/D/8/5D8C65CB-C849-4025-8E95-C3966CAFD8AE/vcredist_x64.exe"; Year = "2008" },
        @{ Name = "vcredist_2010_x86.exe"; Url = "https://download.microsoft.com/download/1/6/5/165255E7-1014-4D0A-B094-B6A430A6BFFC/vcredist_x86.exe"; Year = "2010" },
        @{ Name = "vcredist_2010_x64.exe"; Url = "https://download.microsoft.com/download/1/6/5/165255E7-1014-4D0A-B094-B6A430A6BFFC/vcredist_x64.exe"; Year = "2010" },
        @{ Name = "vcredist_2012_x86.exe"; Url = "https://download.microsoft.com/download/1/6/B/16B06F60-3B20-4FF2-B699-5E9B7962F9AE/VSU_4/vcredist_x86.exe"; Year = "2012" },
        @{ Name = "vcredist_2012_x64.exe"; Url = "https://download.microsoft.com/download/1/6/B/16B06F60-3B20-4FF2-B699-5E9B7962F9AE/VSU_4/vcredist_x64.exe"; Year = "2012" },
        @{ Name = "vcredist_2013_x86.exe"; Url = "https://aka.ms/highdpimfc2013x86enu"; Year = "2013" },
        @{ Name = "vcredist_2013_x64.exe"; Url = "https://aka.ms/highdpimfc2013x64enu"; Year = "2013" },
        @{ Name = "vcredist_2015-2022_x86.exe"; Url = "https://aka.ms/vs/17/release/vc_redist.x86.exe"; Year = "2015-2022" },
        @{ Name = "vcredist_2015-2022_x64.exe"; Url = "https://aka.ms/vs/17/release/vc_redist.x64.exe"; Year = "2012-2022" }
    )

    # --- Download everything up front ---
    foreach ($item in $downloads) {
        $outFile = Join-Path $tempDir $item.Name
        Write-Host "Downloading $($item.Name)..."
        $argumentList = @(
            "--dir=`"$($outFile | Split-Path)`"",
            "--out=`"$(Split-Path -Leaf $outFile)`"",
            "--allow-overwrite=true",
            "--retry-wait=5",
            "--max-connection-per-server=8",
            "--split=8",
            "--min-split-size=1M",
            "`"$($item.Url)`""
        )
        if (![string]::IsNullOrEmpty($regionalWorkaround)) {
            $argumentList += $regionalWorkaround
        }
        Start-Process -FilePath $aria2Exe -ArgumentList $argumentList -NoNewWindow -Wait
    }

    # --- Check Signature ---
    foreach ($item in $downloads) {
        $outFile = Join-Path $tempDir $item.Name
        Write-Host "Verifying signature of $($item.Name)..."
        $signature = Get-AuthenticodeSignature $outFile
        if ($signature.SignerCertificate.Subject -like "*CN=Microsoft Corporation*" -and $signature.Status -eq "Valid") {
            Write-Host "✅ Valid Microsoft signature found from $($item.Name)."
        }
        else {
            Write-Warning "⚠️ $($item.Name) is not signed by Microsoft. The download may get corrupted or your PC is infected with virus."
            $response = Read-Host -Prompt "Would you like to proceed anyway? (Y/N)"
            if ($response -eq 'Y' -or $response -eq 'y') {
                continue
            }
            elseif ($response -eq 'N' -or $response -eq 'n') {
                return 1
            }
            else {
                Write-Host "Invalid input. Please enter Y or N."
            }
        }
    }

    # --- Install VC++ Redistributables ---
    foreach ($item in $downloads | Where-Object { $_.Name -like "vcredist*" }) {
        $exePath = Join-Path $tempDir $item.Name
        $arguments = if ($item.Year -in @("2005", "2008")) { "/q" } else { "/quiet /norestart" }
        Write-Host "Installing $($item.Name)..."
        Start-Process -FilePath $exePath -ArgumentList $arguments -Wait
    }
    
    # --- Install Visual Studio 2010 Tools for Office Runtime ---
    Write-Host "Installing Visual Studio 2010 Tools for Office Runtime ..."
    Start-Process -FilePath "$tempDir\vstor_redist.exe" -ArgumentList "/q /norestart" -Wait

    # --- Cleanup ---
    Write-Host "Cleaning up temporary files..."
    Start-Sleep -Seconds 2
    Remove-Item -Path $tempDir -Recurse -Force -ErrorAction SilentlyContinue
    Remove-Item -Path $flagPath -Force -ErrorAction SilentlyContinue
}

Main