param(
  [switch]$DryRun,
  [string]$Target = "AGENTS.md",
  [string]$SourceUrl = "https://agentpacks.domhubs.com.br/api/lite/agents"
)

$ErrorActionPreference = "Stop"
$ExpectedSha256 = "03d2b7d8258ca271bf84f3afa9e72dfde7accdf55b1f800ffca9a84976e59b79"

if (Test-Path -LiteralPath $Target -PathType Leaf) {
  throw "Arquivo existente; nada foi sobrescrito: $Target"
}

$temporary = Join-Path ([System.IO.Path]::GetTempPath()) ("agentpack-lite-" + [guid]::NewGuid().ToString("N") + ".md")
try {
  Invoke-WebRequest -Uri $SourceUrl -OutFile $temporary -UseBasicParsing
  $actual = (Get-FileHash -Algorithm SHA256 -LiteralPath $temporary).Hash.ToLowerInvariant()
  if ($actual -ne $ExpectedSha256) { throw "Falha de integridade: SHA-256 inesperado ($actual)." }
  if ($DryRun) {
    Write-Output "OK: instalaria $Target (SHA-256 $actual)"
  } else {
    Copy-Item -LiteralPath $temporary -Destination $Target
    Write-Output "AgentPack Lite instalado em $Target"
  }
} finally {
  Remove-Item -LiteralPath $temporary -Force -ErrorAction SilentlyContinue
}