<#
.SYNOPSIS
    BakNRet 隔离沙盒的假数据生成器（在 VM 内运行）。

.DESCRIPTION
    在 C:\BakNRet-Lab\sources 下造出一批**故意带刺**的源目录，用来在真机语义下压测
    Backup.ps1 / Restore.ps1 —— 这些形态在宿主机上不敢随便试：

      * 多 Slot 软件目录（Data / Config / Cache 三个子目录，各自可带排除）；
      * 单文件 Slot（一个 .json 直接当一个 Slot）；
      * 中文 + 空格 + 点的路径名；
      * **真 NTFS 连接点（junction）** —— exFAT 的仓库里造不出来；
      * **被占用文件** —— 后台进程持有句柄，验证「有文件没打进归档」的告警路径；
      * 长路径（接近 260 字符）与 10 层深目录；
      * DefaultExcludes 命中的垃圾文件（Thumbs.db / desktop.ini）与 *.log；
      * 空目录；
      * 一个约 50 MB 的文件，让归档大小/空间预估有实际数字；
      * 一个「源不存在」条目对应的目录（故意不建）。

    幂等：默认只在缺失时创建；-Force 会先删掉 sources 重建（删连接点用 rmdir，避免跟进目标）。
#>

[CmdletBinding()]
param(
    [string]$Root = 'C:\BakNRet-Lab\sources',
    [switch]$Force
)

$ErrorActionPreference = 'Stop'

function New-TextFile {
    param([string]$Path, [string]$Content, [int]$Count = 1)
    $dir = Split-Path -Parent $Path
    if (-not (Test-Path -LiteralPath $dir)) { New-Item -ItemType Directory -Force -Path $dir | Out-Null }
    if ($Count -le 1) {
        Set-Content -LiteralPath $Path -Value $Content -Encoding UTF8
    }
    else {
        Set-Content -LiteralPath $Path -Value (1..$Count | ForEach-Object { "$Content #$_" }) -Encoding UTF8
    }
}

if ($Force -and (Test-Path -LiteralPath $Root)) {
    Write-Host "清除已有沙盒源：$Root"
    Get-ChildItem -LiteralPath $Root -Recurse -Force -Directory -ErrorAction SilentlyContinue |
        Where-Object { $_.Attributes -band [IO.FileAttributes]::ReparsePoint } |
        ForEach-Object { cmd /c rmdir "$($_.FullName)" 2>$null }
    Remove-Item -LiteralPath $Root -Recurse -Force
}
New-Item -ItemType Directory -Force -Path $Root | Out-Null

# --- 1. 多 Slot 软件目录 -----------------------------------------------------
$appA = Join-Path $Root 'AppMultiSlot'
New-TextFile (Join-Path $appA 'Data\settings.json')            '{ "theme": "dark", "slots": 3 }'
New-TextFile (Join-Path $appA 'Data\nested\deep\payload.bin')  'binary-ish-payload' -Count 40
New-TextFile (Join-Path $appA 'Config\app.ini')                '[main]'
New-TextFile (Join-Path $appA 'Config\app.ini.bak')            '[main] backup copy'
New-TextFile (Join-Path $appA 'Cache\cache-01.tmp')            'cache entry' -Count 20
New-TextFile (Join-Path $appA 'Cache\Thumbs.db')               'junk that DefaultExcludes should drop'
New-TextFile (Join-Path $appA 'Cache\desktop.ini')             'junk that DefaultExcludes should drop'
New-TextFile (Join-Path $appA 'Data\session.log')              'log line that an exclusion should drop' -Count 10
New-TextFile (Join-Path $appA 'Data\node_modules\pkg\index.js') 'module.exports = {}'
New-Item -ItemType Directory -Force -Path (Join-Path $appA 'Data\emptydir') | Out-Null

# --- 2. 单文件 Slot ----------------------------------------------------------
$appB = Join-Path $Root 'AppFileSlot'
New-TextFile (Join-Path $appB 'profile.json') '{ "name": "file-slot", "single": true }'
New-TextFile (Join-Path $appB 'readme.txt')   'file slot 的侧车说明'

# --- 3. 中文 + 空格 + 点的路径 ----------------------------------------------
$appC = Join-Path $Root '软件 目录.甲'
New-TextFile (Join-Path $appC '设置\配置 文件.ini') '中文路径内容'
New-TextFile (Join-Path $appC '数据 备份\记录.txt')  '记录内容' -Count 5

# --- 4. 真 NTFS 连接点 -------------------------------------------------------
$realTarget = Join-Path $Root 'AppMultiSlot\Data'
$junction = Join-Path $Root 'JunctionToData'
if (-not (Test-Path -LiteralPath $junction)) {
    $null = New-Item -ItemType Junction -Path $junction -Target $realTarget -ErrorAction SilentlyContinue
}
if (Test-Path -LiteralPath $junction) { Write-Host "连接点已建：$junction -> $realTarget" }

# --- 5. 长路径与深目录 -------------------------------------------------------
$cursor = Join-Path $Root 'AppDeep'
1..10 | ForEach-Object { $cursor = Join-Path $cursor "level$_" }
New-TextFile (Join-Path $cursor 'bottom.txt') 'deep content'
Write-Host ("最长路径长度：{0} 字符" -f (Join-Path $cursor 'bottom.txt').Length)

# --- 6. 50 MB 大文件 ---------------------------------------------------------
$bigDir = Join-Path $Root 'AppBig'
$bigFile = Join-Path $bigDir 'blob-50mb.bin'
if (-not (Test-Path -LiteralPath $bigFile)) {
    New-Item -ItemType Directory -Force -Path $bigDir | Out-Null
    $fs = [IO.File]::Create($bigFile)
    try {
        $rng = [Random]::new(20260926)
        $chunk = [byte[]]::new(1MB)
        for ($i = 0; $i -lt 50; $i++) { $rng.NextBytes($chunk); $fs.Write($chunk, 0, $chunk.Length) }
    }
    finally { $fs.Dispose() }
}
Write-Host ("大文件：{0} MB" -f [math]::Round((Get-Item $bigFile).Length / 1MB, 1))

# --- 7. 被占用文件（后台进程持句柄 90 秒后释放）-----------------------------
$lockDir = Join-Path $Root 'AppLocked'
$lockFile = Join-Path $lockDir 'locked.bin'
New-Item -ItemType Directory -Force -Path $lockDir | Out-Null
New-TextFile $lockFile 'this file is held open by another process'
$holderLines = @(
    '$path = $args[0]'
    '$fs = [IO.File]::Open($path, ''Open'', ''ReadWrite'', ''None'')'
    'try { Start-Sleep -Seconds 90 } finally { $fs.Dispose() }'
)
$holderPath = 'C:\BakNRet-Lab\state\hold-lock.ps1'
Set-Content -LiteralPath $holderPath -Value $holderLines -Encoding UTF8
Start-Process -FilePath 'powershell.exe' -ArgumentList @('-NoProfile', '-ExecutionPolicy', 'Bypass', '-File', $holderPath, $lockFile) -WindowStyle Hidden
Write-Host "已启动占用者进程（持句柄 90 秒）：$lockFile"

# --- 8. 「源不存在」条目对应的目录：故意不建 ---------------------------------
Write-Host '故意不创建 MissingApp（用于验证源缺失只跳过、不失败）'

Write-Host ''
Write-Host '--- 沙盒源清单 ---'
Get-ChildItem -LiteralPath $Root -Force | ForEach-Object {
    $files = @(Get-ChildItem -LiteralPath $_.FullName -Recurse -File -Force -ErrorAction SilentlyContinue)
    $mb = [math]::Round((($files | Measure-Object Length -Sum).Sum) / 1MB, 2)
    "  {0,-24} {1,4} 个文件 {2,8} MB  连接点={3}" -f $_.Name, $files.Count, $mb, [bool]($_.Attributes -band [IO.FileAttributes]::ReparsePoint)
}