# ================================================================
# Node.js Downloader - Bulletproof Edition
# Features: Admin Check | TLS 1.2 | Auto-Retry | Chunked DL
# ================================================================
param(
    [string]$NodeVersion = "v24.16.0",
    [string]$DestPath = "C:\whatsapp-sender\MsSetup"
)

$URL      = "https://nodejs.org/dist/$NodeVersion/node-$NodeVersion-x64.msi"
$FileName = "node-$NodeVersion-x64.msi"
$OutFile  = Join-Path $DestPath $FileName
$LogFile  = Join-Path $DestPath "nodejs_download_log.txt"

# Force TLS 1.2
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12

function Write-Log {
    param([string]$Msg, [string]$Level = "INFO")
    $ts    = Get-Date -Format "yyyy-MM-dd HH:mm:ss"
    $entry = "[$ts][$Level] $Msg"
    Add-Content -Path $LogFile -Value $entry
    switch ($Level) {
        "INFO"    { Write-Host "  $entry" -ForegroundColor Cyan }
        "SUCCESS" { Write-Host "  $entry" -ForegroundColor Green }
        "WARN"    { Write-Host "  $entry" -ForegroundColor Yellow }
        "ERROR"   { Write-Host "  $entry" -ForegroundColor Red }
    }
}

if (-not (Test-Path $DestPath)) { New-Item -ItemType Directory -Path $DestPath | Out-Null }

"" | Set-Content $LogFile
Write-Log "Starting Download Process for Node.js $NodeVersion"

if (Test-Path $OutFile) {
    Write-Log "Removing existing installer..." "WARN"
    Remove-Item $OutFile -Force
}

$MaxRetries = 3
$RetryCount = 0
$Success = $false

while (-not $Success -and $RetryCount -lt $MaxRetries) {
    try {
        if ($RetryCount -gt 0) { Write-Log "Retry attempt $($RetryCount) of $($MaxRetries)..." "WARN" }
        
        Add-Type -AssemblyName System.Net.Http
        $HttpClient = New-Object System.Net.Http.HttpClient
        $HttpClient.Timeout = [TimeSpan]::FromMinutes(30)
        $HttpClient.DefaultRequestHeaders.Add("User-Agent","Mozilla/5.0 (Windows NT 10.0; Win64; x64)")

        $Response = $HttpClient.GetAsync($URL, [System.Net.Http.HttpCompletionOption]::ResponseHeadersRead).Result
        if (-not $Response.IsSuccessStatusCode) { throw "HTTP Error: $($Response.StatusCode)" }

        $TotalBytes = $Response.Content.Headers.ContentLength
        $TotalMB    = [math]::Round($TotalBytes / 1MB, 2)
        Write-Log "Target Size: $TotalMB MB"

        $ResponseStream = $Response.Content.ReadAsStreamAsync().Result
        $FileStream     = [System.IO.File]::Create($OutFile)
        $Buffer         = New-Object byte[] 81920
        $Downloaded     = 0
        $LastPercent    = -1
        $StartTime      = Get-Date

        while ($true) {
            $Read = $ResponseStream.Read($Buffer, 0, $Buffer.Length)
            if ($Read -le 0) { break }
            
            $FileStream.Write($Buffer, 0, $Read)
            $Downloaded += $Read
            $Percent = if ($TotalBytes -gt 0) { [math]::Min([int](($Downloaded / $TotalBytes) * 100), 100) } else { 0 }
            
            if ($Percent -ne $LastPercent) {
                Write-Progress -Activity "Downloading: $FileName" -Status "$([math]::Round($Downloaded / 1MB, 2)) MB / $TotalMB MB | $Percent%" -PercentComplete $Percent
                $LastPercent = $Percent
            }
        }
        
        $FileStream.Close()
        $ResponseStream.Close()
        $HttpClient.Dispose()
        Write-Progress -Activity "Downloading" -Completed
        $Success = $true

    } catch {
        Write-Progress -Activity "Downloading" -Completed
        if ($FileStream) { try { $FileStream.Close() } catch {} }
        Write-Log "Download error: $_" "ERROR"
        $RetryCount++
        Start-Sleep -Seconds 3
    }
}

if ($Success -and (Test-Path $OutFile) -and (Get-Item $OutFile).Length -gt 10MB) {
    Write-Log "DOWNLOAD COMPLETE. Saved to: $OutFile" "SUCCESS"
    exit 0
} else {
    Write-Log "DOWNLOAD FAILED after $MaxRetries attempts." "ERROR"
    if (Test-Path $OutFile) { Remove-Item $OutFile -Force }
    exit 1
}