<#
.SYNOPSIS
    Campaign V blank-world surface probe: compares the client's own
    glReadPixels capture against an OS-level grab of the same frame on screen.

.DESCRIPTION
    The connected gate's verdict comes from the client reading its own default
    framebuffer with glReadPixels. That is one hypothesis about the world being
    blank; it is not evidence. A capture returning zeros is equally consistent
    with "the renderer drew nothing" and with "the read did not return what the
    renderer drew" - and no instrument INSIDE the GL context can tell those
    apart, because both live on the same side of the readback.

    So this probe takes an independent witness. It launches the client VISIBLE
    (the repeat gate minimises it), brings it to the foreground, and grabs the
    composited window rectangle off the desktop with CopyFromScreen at the same
    moment the client writes its own screenshot. Two images of one frame, taken
    through two paths that share nothing below the renderer:

      * both blank   -> the renderer really did draw nothing.
      * GL blank,
        screen fine  -> the frame was drawn and presented; the READBACK is what
                        failed, and every verdict built on it is measuring the
                        capture apparatus rather than the renderer.

    The client's default framebuffer is 4x multisampled (SampleBuffers=1,
    Samples=4 in the capability report), and glReadPixels against a multisampled
    read framebuffer is undefined per the GL spec - which is exactly the kind of
    thing that returns real pixels most of the time and zeros the rest.

    Run this with nothing else on the primary monitor: CopyFromScreen captures
    whatever is composited at those coordinates, so an overlapping window would
    be captured instead of the client.

.PARAMETER ExePath
    Client executable. Defaults to this repo's Release output.

.PARAMETER Runs
    Cycles to run. Default 6.

.PARAMETER Teleloc
    The pinned location, as the full /teleloc argument string.

.PARAMETER MinRenderedBytes
    PNG size below which an image is called blank. Default 500000.
#>
[CmdletBinding()]
param(
    [string]$ExePath,
    [int]$Runs = 6,
    [string]$Teleloc = "0x2E430012 57.895 42.116 16.802 1 0 0 0",
    [int]$MinRenderedBytes = 500000
)

$ErrorActionPreference = 'Stop'
$repo = Split-Path -Parent $PSScriptRoot
if (-not $ExePath) { $ExePath = Join-Path $repo 'src\AcDream.App\bin\Release\net10.0\AcDream.App.exe' }
if (-not (Test-Path $ExePath)) { throw "Client not found at $ExePath." }

if (Get-Process -Name AcDream.App -ErrorAction SilentlyContinue) {
    throw 'AcDream.App is already running. This probe uses the shared test account and must not steal its session.'
}

Add-Type -AssemblyName System.Drawing
Add-Type @'
using System;
using System.Runtime.InteropServices;
public static class WinSurface {
    [DllImport("user32.dll")] public static extern bool SetForegroundWindow(IntPtr hWnd);
    [DllImport("user32.dll")] public static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);
    [DllImport("user32.dll")] public static extern bool IsIconic(IntPtr hWnd);
    [DllImport("user32.dll")] public static extern bool GetClientRect(IntPtr hWnd, out RECT r);
    [DllImport("user32.dll")] public static extern bool ClientToScreen(IntPtr hWnd, ref POINT p);
    [StructLayout(LayoutKind.Sequential)] public struct RECT { public int L, T, R, B; }
    [StructLayout(LayoutKind.Sequential)] public struct POINT { public int X, Y; }
}
'@

$root = Join-Path $env:TEMP "claude\blank-world-surface-$([DateTime]::Now.ToString('HHmmss'))"
New-Item -ItemType Directory -Force -Path $root | Out-Null
$results = @()

for ($i = 1; $i -le $Runs; $i++) {
    $dir = Join-Path $root "run-$i"
    New-Item -ItemType Directory -Force -Path $dir | Out-Null
    # A long trailing sleep keeps the client rendering the same scene while the
    # desktop grab is taken, so both images observe one steady frame.
    Set-Content -Encoding utf8 (Join-Path $dir 'probe.txt') -Value @"
wait world-ready 90000
command /teleloc $Teleloc
wait materialized 1 90000
wait world-visible 30000
sleep 15000
screenshot surface-run 30000
sleep 20000
"@

    $env:ACDREAM_DAT_DIR = Join-Path $env:USERPROFILE "Documents\Asheron's Call"
    $env:ACDREAM_LIVE = '1'
    $env:ACDREAM_TEST_HOST = '127.0.0.1'
    $env:ACDREAM_TEST_PORT = '9000'
    $env:ACDREAM_TEST_USER = 'testaccount'
    $env:ACDREAM_TEST_PASS = 'testpassword'
    $env:ACDREAM_RETAIL_UI = '1'
    $env:ACDREAM_UI_PROBE_SCRIPT = Join-Path $dir 'probe.txt'
    $env:ACDREAM_AUTOMATION_ARTIFACT_DIR = $dir

    $log = Join-Path $dir 'client.log'
    # Normal window style: the frame must be composited on screen to be grabbed.
    $proc = Start-Process -FilePath $ExePath -RedirectStandardOutput $log `
        -RedirectStandardError "$log.err" -PassThru

    $shot = Join-Path $dir 'screenshots\surface-run.png'
    $osShot = Join-Path $dir 'os-grab.png'
    $deadline = (Get-Date).AddSeconds(180)
    while ((Get-Date) -lt $deadline) {
        if (Test-Path $shot) { break }
        if ($proc.HasExited) { break }
        Start-Sleep -Milliseconds 500
    }

    $iconic = $null
    if (Test-Path $shot) {
        # The client is now in its trailing sleep, still rendering this scene.
        Start-Sleep -Milliseconds 800
        try {
            $proc.Refresh()
            $h = $proc.MainWindowHandle
            if ($h -ne [IntPtr]::Zero) {
                $iconic = [WinSurface]::IsIconic($h)
                [WinSurface]::ShowWindow($h, 9) | Out-Null   # SW_RESTORE
                [WinSurface]::SetForegroundWindow($h) | Out-Null
                Start-Sleep -Milliseconds 1200
                $r = New-Object WinSurface+RECT
                [WinSurface]::GetClientRect($h, [ref]$r) | Out-Null
                $p = New-Object WinSurface+POINT
                [WinSurface]::ClientToScreen($h, [ref]$p) | Out-Null
                $w = $r.R - $r.L; $ht = $r.B - $r.T
                if ($w -gt 0 -and $ht -gt 0) {
                    $bmp = New-Object System.Drawing.Bitmap $w, $ht
                    $g = [System.Drawing.Graphics]::FromImage($bmp)
                    $g.CopyFromScreen($p.X, $p.Y, 0, 0, (New-Object System.Drawing.Size $w, $ht))
                    $bmp.Save($osShot, [System.Drawing.Imaging.ImageFormat]::Png)
                    $g.Dispose(); $bmp.Dispose()
                }
            }
        } catch {
            Write-Host "[surface-probe] desktop grab failed: $_"
        }
    }

    $app = Get-Process -Name AcDream.App -ErrorAction SilentlyContinue
    if ($app) {
        $app.CloseMainWindow() | Out-Null
        if (-not $app.WaitForExit(12000)) { $app | Stop-Process -Force }
    }

    $glSize = if (Test-Path $shot) { (Get-Item $shot).Length } else { 0 }
    $osSize = if (Test-Path $osShot) { (Get-Item $osShot).Length } else { 0 }
    $glVerdict = if ($glSize -ge $MinRenderedBytes) { 'RENDERED' } elseif ($glSize -gt 0) { 'BLANK' } else { 'NO-CAPTURE' }
    $osVerdict = if ($osSize -ge $MinRenderedBytes) { 'RENDERED' } elseif ($osSize -gt 0) { 'BLANK' } else { 'NO-CAPTURE' }
    $results += [pscustomobject]@{
        Run = $i; GlCapture = $glVerdict; GlBytes = $glSize
        ScreenGrab = $osVerdict; ScreenBytes = $osSize; WasIconic = $iconic
    }
    Write-Host ("[surface-probe] run {0}/{1}: gl={2} ({3} B)  screen={4} ({5} B)" -f `
        $i, $Runs, $glVerdict, $glSize, $osVerdict, $osSize)

    Start-Sleep -Seconds 10
}

Write-Host ''
$results | Format-Table -AutoSize | Out-String | Write-Host
$split = @($results | Where-Object { $_.GlCapture -ne 'RENDERED' -and $_.ScreenGrab -eq 'RENDERED' })
Write-Host ("[surface-probe] frames where the GL capture blanked but the screen showed the world: {0}/{1}" -f `
    $split.Count, $results.Count)
Write-Host ("[surface-probe] artifacts: {0}" -f $root)