# HTTP-Router: leitet Requests an statische Dateien oder API-Endpoints weiter.

function Invoke-Router {
    param([Parameter(Mandatory=$true)]$Context)

    $request = $Context.Request
    $path = $request.Url.AbsolutePath.TrimEnd('/')
    if ([string]::IsNullOrEmpty($path)) { $path = "/" }
    $method = $request.HttpMethod

    $isApi = $path.StartsWith("/api/")
    if ($isApi) {
        Write-Host (">>> [{0}] {1} {2}" -f (Get-Date -Format "HH:mm:ss.fff"), $method, $path) -ForegroundColor DarkCyan
    }
    $reqStart = Get-Date

    # API-Endpoints
    if ($isApi) {
        $body = $null
        if ($method -in @("POST","PUT","PATCH")) {
            $body = Read-RequestBody -Context $Context
        }
        $query = @{}
        foreach ($key in $request.QueryString.AllKeys) {
            if ($null -ne $key) { $query[$key] = $request.QueryString[$key] }
        }

        try {
            $result = Invoke-ApiHandler -Path $path -Method $method -Body $body -Query $query
            $handlerMs = [int]((Get-Date) - $reqStart).TotalMilliseconds
            if ($null -eq $result) {
                Send-JsonResponse -Context $Context -StatusCode 404 -Body @{ error = "Unknown endpoint: $method $path" }
                Write-Host ("<<< [{0}] {1} {2} -> 404 ({3}ms)" -f (Get-Date -Format "HH:mm:ss.fff"), $method, $path, $handlerMs) -ForegroundColor DarkYellow
            } else {
                $statusCode = 200
                if ($result -is [hashtable] -and $result.ContainsKey('__status')) {
                    $statusCode = $result['__status']
                    $result.Remove('__status')
                }
                Send-JsonResponse -Context $Context -StatusCode $statusCode -Body $result
                $totalMs = [int]((Get-Date) - $reqStart).TotalMilliseconds
                Write-Host ("<<< [{0}] {1} {2} -> {3} (handler={4}ms total={5}ms)" -f (Get-Date -Format "HH:mm:ss.fff"), $method, $path, $statusCode, $handlerMs, $totalMs) -ForegroundColor DarkCyan
            }
        } catch {
            $msg = $_.Exception.Message
            # Client-Disconnects (AbortController) sind harmlos und werden nicht geloggt
            if ($msg -match "Netzwerkname.*nicht.*verfügbar|connection was forcibly closed|aborted by the software|response has been submitted") {
                Write-Host "    [client disconnect] $path" -ForegroundColor DarkGray
            } else {
                Write-Host "<<< [API ERROR] $path -> $msg" -ForegroundColor Red
                Write-Host "    Stack: $($_.ScriptStackTrace)" -ForegroundColor DarkRed
                try {
                    Send-JsonResponse -Context $Context -StatusCode 500 -Body @{
                        error = $msg
                        stack = $_.ScriptStackTrace
                    }
                } catch {}
            }
        }
        return
    }

    # Assets aus dem Projekt-Root (Logos etc.)
    if ($path.StartsWith("/assets/")) {
        $name = $path.Substring("/assets/".Length)
        $name = $name -replace "[^a-zA-Z0-9._-]", ""
        $rootDir = Split-Path -Parent $script:Config.WebRoot
        $file = Join-Path $rootDir $name
        # Branding-Logos NIE cachen — sonst sieht der User nach dem Upload
        # weiter die alte Version, auch wenn die URL gleich bleibt.
        $extraHeaders = $null
        if ($name -like 'branding-logo.*') {
            $extraHeaders = @{ 'Cache-Control' = 'no-store, max-age=0' }
        }
        Send-FileResponse -Context $Context -FilePath $file -ExtraHeaders $extraHeaders
        return
    }

    # Reports (HTML-Reports werden in Temp gespeichert)
    if ($path.StartsWith("/reports/")) {
        $name = $path.Substring("/reports/".Length)
        $name = $name -replace "[^a-zA-Z0-9._-]", ""
        $file = Join-Path $script:Config.ReportDir $name
        Send-FileResponse -Context $Context -FilePath $file
        return
    }

    # Statische Dateien aus www/
    $relativePath = if ($path -eq "/") { "index.html" } else { $path.TrimStart('/') }
    $relativePath = $relativePath -replace '\.\.', ''  # path traversal blocken
    $file = Join-Path $script:Config.WebRoot $relativePath

    if (Test-Path $file -PathType Leaf) {
        Send-FileResponse -Context $Context -FilePath $file
    } else {
        # SPA fallback - alle nicht erkannten Pfade auf index.html
        Send-FileResponse -Context $Context -FilePath (Join-Path $script:Config.WebRoot "index.html")
    }
}