# get-vnc.ps1
# Downloads a portable VNC server (UltraVNC) for Windows and places its
# files into a local "vnc" folder so web-vnc can auto-launch it with --spawn.
#
# Usage (from repo root):  .\scripts\get-vnc.ps1
# Override the download URL(s): .\scripts\get-vnc.ps1 -Url "https://.../UltraVNC_x64.zip"
#
# If all download attempts fail, the script opens https://uvnc.com/downloads.html
# in your browser — download the UltraVNC .zip (NOT the installer), extract it and
# copy winvnc.exe together with its companion .dll/.dsm files into the project's
# "vnc" folder, then run `run.bat`.

[CmdletBinding()]
param(
  [string[]]$Url = @(
    "https://downloads.sourceforge.net/project/ultravnc/UltraVNC%201.4.3.0%20bin/UltraVNC_1.4.3.0_x64.zip",
    "https://downloads.sourceforge.net/project/ultravnc/UltraVNC_1.4.3.0/UltraVNC_1.4.3.0_x64.zip",
    "https://sourceforge.net/projects/ultravnc/files/UltraVNC%201.4.3.0%20bin/UltraVNC_1.4.3.0_x64.zip/download"
  )
)

$ErrorActionPreference = "Stop"
$repoRoot = Resolve-Path (Join-Path $PSScriptRoot "..")
$vncDir = Join-Path $repoRoot "vnc"
New-Item -ItemType Directory -Force -Path $vncDir | Out-Null

$work = Join-Path $env:TEMP ("webvnc-vnc-" + [guid]::NewGuid())
New-Item -ItemType Directory -Force -Path $work | Out-Null

function Test-Zip([string]$path) {
  if (-not (Test-Path $path)) { return $false }
  $fs = [System.IO.File]::OpenRead($path)
  try {
    $b = New-Object byte[] 4
    $n = $fs.Read($b, 0, 4)
    return ($n -ge 2 -and $b[0] -eq 0x50 -and $b[1] -eq 0x4B)  # "PK"
  } finally { $fs.Close() }
}

function Get-Zip {
  param([string[]]$urls)
  $ua = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 web-vnc-installer"
  foreach ($u in $urls) {
    $archive = Join-Path $work "vnc.zip"
    Remove-Item $archive -ErrorAction SilentlyContinue
    Write-Host ""
    Write-Host "Trying: $u"
    foreach ($attempt in 1..2) {
      try {
        Invoke-WebRequest -Uri $u -OutFile $archive -UseBasicParsing -TimeoutSec 300 -UserAgent $ua -MaximumRedirection 20
        if (Test-Zip $archive) {
          $len = [Math]::Round((Get-Item $archive).Length / 1MB, 1)
          Write-Host "  downloaded zip (${len} MB)"
          return $archive
        }
        Write-Host "  response was not a zip (HTML page?), retrying ..."
        Remove-Item $archive -ErrorAction SilentlyContinue
        Start-Sleep -Seconds 2
      } catch {
        Write-Host "  attempt ${attempt} failed: $($_.Exception.Message)"
        Start-Sleep -Seconds 2
      }
    }
  }
  return $null
}

function Manual-Fallback {
  $page = "https://uvnc.com/downloads.html"
  Write-Host ""
  Write-Host "============================================================" -ForegroundColor Yellow
  Write-Host "Automatic download failed. Opening the UltraVNC download page." -ForegroundColor Yellow
  Write-Host "============================================================" -ForegroundColor Yellow
  try { Start-Process $page } catch { Write-Host "Open manually: $page" }
  Write-Host ""
  Write-Host "Manual steps:"
  Write-Host "  1. On the page, download the UltraVNC .zip archive (the portable"
  Write-Host "     package, NOT the installer)."
  Write-Host "  2. Extract it."
  Write-Host "  3. Copy winvnc.exe AND its companion .dll/.dsm files (everything"
  Write-Host "     from the extracted folder) into this folder:"
  Write-Host "       $vncDir"
  Write-Host "  4. Run:  .\run.bat"
  Write-Host ""
}

try {
  $archive = Get-Zip -urls $Url
  if (-not $archive) { Manual-Fallback; exit 1 }

  Write-Host "Extracting ..."
  Expand-Archive -Path $archive -DestinationPath $work -Force

  $server = Get-ChildItem -Recurse -Path $work -Filter "winvnc.exe" -ErrorAction SilentlyContinue | Select-Object -First 1
  if (-not $server) {
    $server = Get-ChildItem -Recurse -Path $work -Filter "tvnserver.exe" -ErrorAction SilentlyContinue | Select-Object -First 1
  }
  if (-not $server) {
    Write-Host "winvnc.exe not found in the archive." -ForegroundColor Yellow
    Manual-Fallback
    exit 1
  }

  $srcDir = $server.DirectoryName
  Write-Host "Found VNC server in: $srcDir"
  Write-Host "Copying files into:  $vncDir"
  Copy-Item -Path (Join-Path $srcDir "*") -Destination $vncDir -Recurse -Force

  Write-Host ""
  Write-Host "Done. Installed: $(Join-Path $vncDir $server.Name)" -ForegroundColor Green
  Write-Host "Now run:  .\run.bat"
}
finally {
  Remove-Item -Path $work -Recurse -Force -ErrorAction SilentlyContinue
}