[CmdletBinding()]

param(

[string]$Version = $env:AGENTVIEW_VERSION,

[string]$InstallDir = $env:AGENTVIEW_INSTALL_DIR,

[string]$Repo = $(if ($env:AGENTVIEW_REPO) { $env:AGENTVIEW_REPO } else { "moritzWa/agentview" }),

[string]$ReleaseBaseUrl = $env:AGENTVIEW_RELEASE_BASE_URL,

[int]$WaitForProcessId = 0,

[string]$PreviousVersion = "",

[switch]$CleanupStaging,

[switch]$SkipPathUpdate

)

$ErrorActionPreference = "Stop"

Set-StrictMode -Version 2.0

function Write-AgentviewMessage([string]$Message) {

Write-Host "agentview: $Message"

}

function Copy-OrDownload([string]$Source, [string]$Destination) {

if (Test-Path -LiteralPath $Source) {

Copy-Item -LiteralPath $Source -Destination $Destination -Force

} else {

Invoke-WebRequest -UseBasicParsing -Uri $Source -OutFile $Destination

}

}

function Install-AgentviewAlias([string]$Source, [string]$Destination) {

if (Test-Path -LiteralPath $Destination) {

$reported = ""

try { $reported = (& $Destination --version 2>$null | Out-String).Trim() } catch {}

if ($reported -notmatch '^agentview [0-9]+\.[0-9]+\.[0-9]+$') {

Write-AgentviewMessage "left unrelated existing command in place: $Destination"

return

}

}

Copy-Item -LiteralPath $Source -Destination $Destination -Force

}

if ($WaitForProcessId -gt 0) {

$running = Get-Process -Id $WaitForProcessId -ErrorAction SilentlyContinue

if ($running) {

Write-AgentviewMessage "waiting for the running agentview process to exit"

$running.WaitForExit()

}

}

if (-not $Version) { $Version = "latest" }

if (-not $InstallDir) {

$base = if ($env:LOCALAPPDATA) { $env:LOCALAPPDATA } else { Join-Path $env:USERPROFILE "AppData\Local" }

$InstallDir = Join-Path $base "Programs\agentview\bin"

}

if ($Repo -notmatch '^[A-Za-z0-9_.-]+/[A-Za-z0-9_.-]+$') {

throw "repository must have the form OWNER/REPO"

}

$architecture = [System.Runtime.InteropServices.RuntimeInformation]::OSArchitecture.ToString()

switch ($architecture) {

"X64" { $target = "x86_64-pc-windows-msvc" }

default { throw "no native Windows release is available for $architecture yet; use Windows x64 or WSL 2" }

}

if ($Version -eq "latest") {

$headers = @{ "Accept" = "application/vnd.github+json" }

if ($env:GH_TOKEN) { $headers["Authorization"] = "Bearer $($env:GH_TOKEN)" }

$release = Invoke-RestMethod -Headers $headers -Uri "https://api.github.com/repos/$Repo/releases/latest"

$tag = [string]$release.tag_name

} else {

$tag = "v$($Version.TrimStart('v'))"

}

if ($tag -notmatch '^v[0-9]+\.[0-9]+\.[0-9]+$') {

throw "release version must have the form MAJOR.MINOR.PATCH (received: $tag)"

}

$resolvedVersion = $tag.Substring(1)

$stem = "agentview-$resolvedVersion-$target"

$archive = "$stem.zip"

$checksum = "$archive.sha256"

$temporary = Join-Path ([System.IO.Path]::GetTempPath()) ("agentview-install-" + [guid]::NewGuid())

$staged = Join-Path $InstallDir (".agentview.install." + $PID + ".exe")

try {

New-Item -ItemType Directory -Path $temporary -Force | Out-Null

if ($ReleaseBaseUrl) {

$base = $ReleaseBaseUrl.TrimEnd('/', '\') + "\$tag"

if ($ReleaseBaseUrl -match '^https?://') { $base = $ReleaseBaseUrl.TrimEnd('/') + "/$tag" }

} else {

$base = "https://github.com/$Repo/releases/download/$tag"

}

Write-AgentviewMessage "downloading $tag for $target"

Copy-OrDownload "$base/$archive" (Join-Path $temporary $archive)

Copy-OrDownload "$base/$checksum" (Join-Path $temporary $checksum)

$expected = ((Get-Content -LiteralPath (Join-Path $temporary $checksum) -TotalCount 1) -split '\s+')[0]

if ($expected -notmatch '^[0-9a-fA-F]{64}$') { throw "release checksum file is malformed" }

$actual = (Get-FileHash -Algorithm SHA256 -LiteralPath (Join-Path $temporary $archive)).Hash

if ($actual -ne $expected) { throw "release checksum verification failed" }

Expand-Archive -LiteralPath (Join-Path $temporary $archive) -DestinationPath $temporary -Force

$binary = Join-Path (Join-Path $temporary $stem) "agentview.exe"

if (-not (Test-Path -LiteralPath $binary -PathType Leaf)) {

throw "release archive does not contain $stem/agentview.exe"

}

New-Item -ItemType Directory -Path $InstallDir -Force | Out-Null

Copy-Item -LiteralPath $binary -Destination $staged -Force

$reported = (& $staged --version | Out-String).Trim()

if ($reported -ne "agentview $resolvedVersion") {

throw "downloaded binary reported an unexpected version: $reported"

}

Move-Item -LiteralPath $staged -Destination (Join-Path $InstallDir "agentview.exe") -Force

$canonical = Join-Path $InstallDir "agentview.exe"

Install-AgentviewAlias $canonical (Join-Path $InstallDir "av.exe")

if (-not $SkipPathUpdate) {

$userPath = [Environment]::GetEnvironmentVariable("Path", "User")

$parts = @($userPath -split ';' | Where-Object { $_ })

if ($parts -notcontains $InstallDir) {

[Environment]::SetEnvironmentVariable("Path", (($parts + $InstallDir) -join ';'), "User")

}

if (($env:Path -split ';') -notcontains $InstallDir) { $env:Path = "$InstallDir;$env:Path" }

}

Write-AgentviewMessage "installed agentview $resolvedVersion to $InstallDir\agentview.exe"

Write-AgentviewMessage "installed shorthand: av"

Write-AgentviewMessage "open a new terminal, then run: agentview (or av)"

if ($PreviousVersion) {

if ($PreviousVersion -eq $resolvedVersion) {

Write-AgentviewMessage "agentview is already up to date at $resolvedVersion"

} else {

Write-AgentviewMessage "updated agentview from $PreviousVersion to $resolvedVersion"

}

}

} finally {

Remove-Item -LiteralPath $staged -Force -ErrorAction SilentlyContinue

Remove-Item -LiteralPath $temporary -Recurse -Force -ErrorAction SilentlyContinue

if ($CleanupStaging -and $PSCommandPath) {

$stagingDirectory = Split-Path -Parent $PSCommandPath

$stagingParent = Split-Path -Parent $stagingDirectory

$temporaryRoot = [System.IO.Path]::GetTempPath().TrimEnd('\', '/')

$stagingName = Split-Path -Leaf $stagingDirectory

if ($stagingParent.TrimEnd('\', '/') -eq $temporaryRoot -and $stagingName -match '^agentview-update-[0-9]+-[0-9]+$') {

Remove-Item -LiteralPath $PSCommandPath -Force -ErrorAction SilentlyContinue

Remove-Item -LiteralPath $stagingDirectory -Force -ErrorAction SilentlyContinue

}

}

}