# Radar installer for Windows
# Usage: irm https://raw.githubusercontent.com/skyhook-io/radar/main/install.ps1 | iex

$ErrorActionPreference = "Stop"

$Repo = "skyhook-io/radar"
$BinaryName = "kubectl-radar.exe"
$InstallDir = "$env:LOCALAPPDATA\radar"

# Only amd64 is supported on Windows
$Arch = "amd64"

# Resolve the ordinary GitHub web redirect instead of using the REST API.
# The API's unauthenticated per-IP quota can be exhausted by unrelated users
# behind the same NAT, while this redirect is the same path browsers use.
Write-Host "Fetching latest release..." -ForegroundColor Cyan
try {
    $Release = Invoke-WebRequest -Uri "https://github.com/$Repo/releases/latest" -UseBasicParsing -MaximumRedirection 5

    # Windows PowerShell 5.1 and PowerShell 7 expose the final response URI on
    # different response objects. Both runtimes are supported by this script.
    if ($Release.BaseResponse.PSObject.Properties["ResponseUri"]) {
        $LatestReleaseUri = $Release.BaseResponse.ResponseUri
    } elseif ($Release.BaseResponse.PSObject.Properties["RequestMessage"]) {
        $LatestReleaseUri = $Release.BaseResponse.RequestMessage.RequestUri
    } else {
        throw "GitHub response did not include the final release URL"
    }

    $ExpectedPathPrefix = "/$Repo/releases/tag/v"
    if ($LatestReleaseUri.Scheme -ne "https" -or
        $LatestReleaseUri.Host -ne "github.com" -or
        $LatestReleaseUri.UserInfo -ne "" -or
        $LatestReleaseUri.Port -ne 443 -or
        $LatestReleaseUri.Query -ne "" -or
        $LatestReleaseUri.Fragment -ne "" -or
        -not $LatestReleaseUri.AbsolutePath.StartsWith($ExpectedPathPrefix, [StringComparison]::Ordinal)) {
        throw "GitHub redirected to an unexpected release URL: $LatestReleaseUri"
    }

    $Version = $LatestReleaseUri.AbsolutePath.Substring($ExpectedPathPrefix.Length)
    if ($Version -notmatch '^[0-9]+\.[0-9]+\.[0-9]+(?:-[0-9A-Za-z.-]+)?(?:\+[0-9A-Za-z.-]+)?$') {
        throw "GitHub returned an unexpected release tag: v$Version"
    }
} catch {
    Write-Host "Failed to fetch latest version: $_" -ForegroundColor Red
    exit 1
}

Write-Host "Installing Radar v$Version..." -ForegroundColor Cyan

# Download
$Filename = "radar_v${Version}_windows_${Arch}.zip"
$DownloadUrl = "https://github.com/$Repo/releases/download/v$Version/$Filename"
$ChecksumsUrl = "https://github.com/$Repo/releases/download/v$Version/checksums.txt"
$TmpDir = Join-Path $env:TEMP "radar-install-$(Get-Random)"
$ZipPath = Join-Path $TmpDir $Filename
$ChecksumsPath = Join-Path $TmpDir "checksums.txt"

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

Write-Host "Downloading $DownloadUrl..." -ForegroundColor Cyan
try {
    Invoke-WebRequest -Uri $DownloadUrl -OutFile $ZipPath -UseBasicParsing
} catch {
    Write-Host "Failed to download: $_" -ForegroundColor Red
    Remove-Item -Path $TmpDir -Recurse -Force -ErrorAction SilentlyContinue
    exit 1
}

Write-Host "Downloading $ChecksumsUrl..." -ForegroundColor Cyan
try {
    Invoke-WebRequest -Uri $ChecksumsUrl -OutFile $ChecksumsPath -UseBasicParsing
} catch {
    Write-Host "Failed to download checksums: $_" -ForegroundColor Red
    Remove-Item -Path $TmpDir -Recurse -Force -ErrorAction SilentlyContinue
    exit 1
}

Write-Host "Verifying SHA-256 checksum..." -ForegroundColor Cyan
$ChecksumContent = Get-Content -Path $ChecksumsPath -Raw
$ExpectedHash = $null
foreach ($line in ($ChecksumContent -split "`r?`n")) {
    $parts = $line.Trim() -split '\s+'
    if ($parts.Count -ge 2 -and ($parts[1] -eq $Filename -or $parts[1] -eq "*$Filename")) {
        $ExpectedHash = $parts[0]
        break
    }
}

if (-not $ExpectedHash) {
    Write-Host "Failed to find checksum for $Filename in checksums.txt" -ForegroundColor Red
    Remove-Item -Path $TmpDir -Recurse -Force -ErrorAction SilentlyContinue
    exit 1
}

$ActualHash = (Get-FileHash -Path $ZipPath -Algorithm SHA256).Hash.ToLowerInvariant()
if ($ActualHash -ne $ExpectedHash.ToLowerInvariant()) {
    Write-Host "Checksum verification failed for $Filename" -ForegroundColor Red
    Write-Host "Expected: $ExpectedHash" -ForegroundColor Red
    Write-Host "Actual:   $ActualHash" -ForegroundColor Red
    Remove-Item -Path $TmpDir -Recurse -Force -ErrorAction SilentlyContinue
    exit 1
}

# Extract
Write-Host "Extracting..." -ForegroundColor Cyan
Expand-Archive -Path $ZipPath -DestinationPath $TmpDir -Force

# Install
if (-not (Test-Path $InstallDir)) {
    New-Item -ItemType Directory -Path $InstallDir -Force | Out-Null
}

Move-Item -Path (Join-Path $TmpDir $BinaryName) -Destination $InstallDir -Force

# Create radar.exe symlink/copy for convenience
$RadarExe = Join-Path $InstallDir "radar.exe"
Copy-Item -Path (Join-Path $InstallDir $BinaryName) -Destination $RadarExe -Force

# Cleanup
Remove-Item -Path $TmpDir -Recurse -Force -ErrorAction SilentlyContinue

# Add to PATH if not already there
$UserPath = [Environment]::GetEnvironmentVariable("Path", "User")
if ($UserPath -notlike "*$InstallDir*") {
    Write-Host "Adding $InstallDir to PATH..." -ForegroundColor Cyan
    [Environment]::SetEnvironmentVariable("Path", "$UserPath;$InstallDir", "User")
    $env:Path = "$env:Path;$InstallDir"
}

Write-Host ""
Write-Host "Radar v$Version installed successfully!" -ForegroundColor Green
Write-Host ""
Write-Host "Usage:" -ForegroundColor Yellow
Write-Host "  kubectl radar          # as kubectl plugin"
Write-Host "  kubectl-radar          # standalone"
Write-Host "  radar                  # short alias"
Write-Host ""
Write-Host "Run 'radar --help' for more options." -ForegroundColor Yellow
Write-Host ""
Write-Host "Note: Restart your terminal for PATH changes to take effect." -ForegroundColor Cyan