# 2b V6/V7 proof: v3 text injection into a dedicated WinForms target window,
# read back from that process itself.
# ASCII-only source (PS 5.1 decodes BOM-less .ps1 as GBK; see personal lessons).
# Non-ASCII payloads are built from explicit code points, never literals.
#
# Usage:
#   powershell -ExecutionPolicy Bypass -File tools\text_injection_proof.ps1
#
# Chain: viewer-core text_check --units <utf16> -> v3 agent SendInput
#        KEYEVENTF_UNICODE -> foreground WinForms TextBox -> self-reported text.
#
# Why NOT Notepad (2026-10-30): Windows 11 Notepad hosts all tabs in ONE
# process and this dev box had a user document open in it - injecting "into
# Notepad" would mean injecting into the user's real file. The WinForms target
# is a separate process we own, opened on an empty field.
#
# Foreground handling (measured, not assumed): a form with TopMost=true that
# is activated at startup KEEPS foreground for seconds; AppActivate /
# SetForegroundWindow called from here actually STEALS it away. So we assert
# the target is foreground before injecting, and refuse to inject otherwise -
# a stray injection would land in whatever window was foreground.

$ErrorActionPreference = "Stop"
$repo = "D:\working\projects\yuankong\remote"
$tmp  = "$env:TEMP\remote-text-proof"
$base = "D:\working\environment"

$env:RUSTUP_HOME = "$base\rust"
$env:CARGO_HOME  = "$base\cargo"
$env:PATH = "$base\mingw64\bin;$base\cargo\bin;" + $env:PATH

Add-Type -TypeDefinition @"
using System;
using System.Runtime.InteropServices;
public static class WinFg {
  [DllImport("user32.dll")] public static extern IntPtr GetForegroundWindow();
}
"@

New-Item -ItemType Directory -Force -Path $tmp | Out-Null
$pidFile    = "$tmp\target.pid"
$stopFile   = "$tmp\stop.flag"
$resultFile = "$tmp\received.txt"
Remove-Item $pidFile,$stopFile,$resultFile -ErrorAction SilentlyContinue

function Wait-File {
    param([string]$Path, [int]$TimeoutMs = 15000)
    $tries = 0
    while (-not (Test-Path $Path) -and $tries -lt ($TimeoutMs / 150)) {
        Start-Sleep -Milliseconds 150; $tries++
    }
    if (-not (Test-Path $Path)) { throw "file did not appear: $Path" }
}

function Read-Received {
    Wait-File $resultFile
    $bytes = [System.IO.File]::ReadAllBytes($resultFile)
    $text = [System.Text.Encoding]::UTF8.GetString($bytes)
    if ($text.Length -gt 0 -and $text[0] -eq [char]0xFEFF) { $text = $text.Substring(1) }
    return $text
}

function CodePointsToString([int[]]$cps) {
    -join ($cps | ForEach-Object { [char]$_ })
}

function Show-Text([string]$s) {
    # ASCII-safe console preview: non-ASCII rendered as U+XXXX
    ($s.ToCharArray() | ForEach-Object {
        if ([int]$_ -ge 32 -and [int]$_ -lt 127) { $_ } else { "U+{0:X4}" -f [int]$_ }
    }) -join ""
}

function Assert-TargetForeground([IntPtr]$hwnd) {
    $fg = [WinFg]::GetForegroundWindow()
    if ($fg -ne $hwnd) {
        throw "foreground is $fg, not target $hwnd - refusing to inject (would hit another app)"
    }
}

function Send-Units([int[]]$cps, [IntPtr]$hwnd, [int]$delayMs = 1500) {
    $units = $cps -join ","
    $exe = "$repo\target\debug\examples\text_check.exe"
    if (-not (Test-Path $exe)) { throw "missing $exe (cargo build -p viewer-core --example text_check)" }
    Assert-TargetForeground $hwnd
    & $exe --port 47800 --code t --units $units --delay $delayMs --hold 800
    $code = $LASTEXITCODE
    Assert-TargetForeground $hwnd   # 注入窗口在 --delay 期间必须仍是靶窗
    if ($code -ne 0) { throw "text_check exited $code" }
    Start-Sleep -Milliseconds 500
}

Write-Host "=== 0. ensure CURRENT v3 agent is the one running ==="
$ag = Get-Process agent -ErrorAction SilentlyContinue
$agentExe = "$repo\target\release\agent.exe"
if ($ag -and (Get-Item $agentExe).LastWriteTime -gt $ag.StartTime) {
    Write-Host "  running agent predates current build; restarting"
    Stop-Process -Name agent -Force -ErrorAction SilentlyContinue
    Start-Sleep -Milliseconds 800
    $ag = $null
}
if (-not $ag) {
    Start-Process -FilePath $agentExe -ArgumentList "--port","47800","--code","t" -WindowStyle Hidden
    Start-Sleep -Seconds 1
    Write-Host "  agent started (v3)"
}

Write-Host "=== 1. launch WinForms target (own process, empty field) ==="
# NO -WindowStyle Hidden: the hidden host makes the form invisible, and an
# invisible window can never be foreground (measured 2026-10-30).
Start-Process powershell.exe -ArgumentList "-NoProfile","-ExecutionPolicy","Bypass",`
    "-File","$repo\tools\text_target.ps1","-PidFile",$pidFile,`
    "-ResultFile",$resultFile,"-StopFile",$stopFile
Wait-File $pidFile
$tid = [int](Get-Content $pidFile -Raw).Trim()
$tp = Get-Process -Id $tid
Start-Sleep -Milliseconds 1200
$hwnd = $tp.MainWindowHandle
if ($hwnd -eq 0) { throw "target has no window handle" }
Write-Host "  target pid=$tid hwnd=$hwnd title=[$($tp.MainWindowTitle)]"
Assert-TargetForeground $hwnd
Write-Host "  target is foreground: yes"

Write-Host "=== 2. V6: four CJK BMP characters (Ni Hao Shi Jie) ==="
$cjk = @(0x4F60, 0x597D, 0x4E16, 0x754C)
Send-Units $cjk $hwnd
$got6 = Read-Received
$exp6 = CodePointsToString $cjk
Write-Host ("  received [{0}]  expected [{1}]" -f (Show-Text $got6), (Show-Text $exp6))
if ($got6 -ne $exp6) { throw "V6 FAIL" }
Write-Host "  V6 PASS - BMP CJK arrived intact through v3 Text + KEYEVENTF_UNICODE"

Write-Host "=== 3. V7: exclaim + emoji U+1F600 (UTF-16 surrogate pair) appended ==="
$mix = @(0x0021, 0xD83D, 0xDE00)
Send-Units $mix $hwnd
$got7 = Read-Received
$exp7 = $exp6 + (CodePointsToString $mix)
Write-Host ("  received len={0} [{1}]" -f $got7.Length, (Show-Text $got7))
Write-Host ("  expected len={0} [{1}]" -f $exp7.Length, (Show-Text $exp7))
if ($got7 -ne $exp7) { throw "V7 FAIL - mismatch" }
if ($got7.Contains([char]0xFFFD)) { throw "V7 FAIL - U+FFFD present: pair got split" }
Write-Host "  V7 PASS - surrogate pair survived as one character, no replacement char"

Write-Host "=== 4. negative guard: missing --units must NOT inject anything ==="
$before = Read-Received
$exe = "$repo\target\debug\examples\text_check.exe"
# Omit --units entirely (passing an empty string would be eaten by PowerShell
# argument handling and parsed as the next flag). viewer-core's parse_units
# rejects the degenerate input before any session is even opened.
# No 2>&1 here: viewer-core logs go to stderr by design; merging them turns
# every normal log line into a PowerShell error record.
& $exe --port 47800 --code t --delay 100 --hold 100 | Out-Null
$emptyCode = $LASTEXITCODE
Write-Host "  exit=$emptyCode (expected non-zero: tool rejects empty --units)"
if ($emptyCode -eq 0) { throw "FAIL - empty units should be rejected by the tool" }
Start-Sleep -Milliseconds 400
$after = Read-Received
if ($after -ne $before) { throw "FAIL - target text changed unexpectedly: [$after]" }
Write-Host "  guard PASS - no injection happened, target text unchanged"

Write-Host "=== 5. stop target ==="
New-Item -ItemType File -Force -Path $stopFile | Out-Null
$tries = 0
while ((Get-Process -Id $tid -ErrorAction SilentlyContinue) -and $tries -lt 40) {
    Start-Sleep -Milliseconds 150; $tries++
}
Write-Host "=== PROOF COMPLETE: final target text = [$(Show-Text (Read-Received))] ==="