<#
.SYNOPSIS
    按 BackupList.txt 执行备份。

.DESCRIPTION
    与旧版相比的核心变化：

      1. 退出码可靠 —— 不再用 Start-Process -PassThru（在 PowerShell 7.7.0-preview.4 上
         ExitCode 恒为 $null，会把成功的压缩判成失败），改用 Invoke-ExternalCommand。
      2. 先写临时归档 → 校验 → 原子替换。中断或断电只会留下 .tmp 文件，
         不会污染正式归档；也不会再出现"半个归档被下次增量续写"的情况。
      3. 不再使用 7z 的 u（更新）模式。7z 默认是固实压缩，u 本来就要重压大部分数据，
         收益极小，却让排除规则和删除操作永远无法生效（旧归档里会一直留着已删文件）。
         现在每次都从零打包，于是"排除规则改动"和"源里删掉的文件"都能真正反映到归档。
      4. 每个条目写进 manifest.json：源、归档、时间、退出码、校验结果、失败原因。
         跳过和失败从此有据可查，而不是只剩一行滚过去的控制台告警。
      5. 结尾按失败数 exit，并写日志文件，计划任务能正确判断成败。
      6. 磁盘空间守卫：放不下就拒绝该条目，低于阈值则告警。
#>

[CmdletBinding()]
param(
    [Parameter()]
    [string]$BackupListPath = (Join-Path $PSScriptRoot 'BackupList.txt'),

    [Parameter()]
    [string]$BackupDir,

    [Parameter()]
    [string]$ConfigPath = (Join-Path $PSScriptRoot 'BackupConfig.psd1'),

    [Parameter()]
    [string]$KeyFile,

    # 只处理匹配这些通配符的条目（匹配原始路径或归档基础名）
    [Parameter()]
    [string[]]$Only = @(),

    # 跳过匹配这些通配符的条目
    [Parameter()]
    [string[]]$Skip = @(),

    # 忽略"源未更新"判断，强制重新打包
    [Parameter()]
    [switch]$Force,

    # 成功后在 snapshots 目录留一份带时间戳的副本
    [Parameter()]
    [switch]$Snapshot,

    # 额外计算归档的 SHA256 写入 manifest（大归档会更慢）
    [Parameter()]
    [switch]$Hash,

    # 抑制压缩工具的实时输出（日志与 manifest 不受影响）
    [Parameter()]
    [switch]$QuietTool,

    # 允许用"有警告"的不完整归档覆盖已有的完整归档（默认拒绝）
    [Parameter()]
    [switch]$AcceptWarnings,

    # 只打印将要做什么，不实际写入
    [Parameter()]
    [switch]$DryRun
)

$ErrorActionPreference = 'Stop'

# ============================================================================
# 载入依赖
# ============================================================================

$modulePath = Join-Path $PSScriptRoot 'Common.psm1'
if (-not (Test-Path -LiteralPath $modulePath)) {
    Write-Error "找不到依赖模块：$modulePath，请确保所有文件在同一目录。"
    exit 1
}
Import-Module $modulePath -Force

if ($PSBoundParameters.ContainsKey('Verbose')) { Set-BaknretDebug }

$script:Config = Get-BaknretConfig -Path $ConfigPath

function Resolve-ConfigPath {
    param([string]$Path, [string]$Default)
    $value = if ($Path) { $Path } else { $Default }
    if (-not [System.IO.Path]::IsPathRooted($value)) {
        $value = Join-Path $PSScriptRoot $value
    }
    return $value
}

if (-not $BackupDir) { $BackupDir = Resolve-ConfigPath -Path $null -Default $script:Config.BackupDir }
$logDir = Resolve-ConfigPath -Path $null -Default $script:Config.LogDir
$snapshotDir = Resolve-ConfigPath -Path $null -Default $script:Config.SnapshotDir
$catalogPath = Resolve-CatalogPath -Configured $script:Config.SoftwareCatalog -Root $PSScriptRoot
$manifestPath = Join-Path $BackupDir 'manifest.json'

$logPath = Start-BaknretLog -Directory $logDir -Prefix 'backup'
Write-Log "日志文件：$logPath"
Write-Log "备份目录：$BackupDir"
Write-Log ("软件名录：{0}{1}" -f $catalogPath, $(if (Test-Path -LiteralPath $catalogPath) { '' } else { '（不存在，将只支持字面路径）' }))

if (-not (Test-Administrator)) {
    Write-Log '建议以管理员身份运行以获取完整的目录访问权限' -Level WARN
}

# ============================================================================
# 准备
# ============================================================================

if (-not (Test-Path -LiteralPath $BackupDir)) {
    New-Item -ItemType Directory -Path $BackupDir -Force | Out-Null
    Write-Log "创建备份目录: $BackupDir" -Level DEBUG
}

if (-not (Test-Path -LiteralPath $BackupListPath)) {
    $template = "# BackupList.txt`n# 语法: <路径> [ :: <排除模式>[,<排除模式>...] ] [ @<标记> ]`n# 示例: %UserProfile%\.ssh`n"
    [System.IO.File]::WriteAllText($BackupListPath, $template, [System.Text.UTF8Encoding]::new($false))
    Write-Log '模板 BackupList.txt 已创建，请编辑后重试。' -Level INFO
    Stop-BaknretLog
    exit 0
}

$tool = Resolve-CompressionTool
if (-not $tool) {
    Write-Log '没有找到可用的压缩工具。' -Level ERROR
    Stop-BaknretLog
    exit 1
}

$toolVersion = try {
    $info = (Get-Item -LiteralPath $tool.Command -ErrorAction Stop).VersionInfo
    if ($info.ProductVersion) { $info.ProductVersion } elseif ($info.FileVersion) { $info.FileVersion } else { $null }
} catch { $null }
Write-Log ("压缩工具：{0}{1}" -f $tool.Name, $(if ($toolVersion) { "（$toolVersion）" } else { '' }))

$manifest = Read-BaknretManifest -Path $manifestPath
$manifest.compressor = [pscustomobject]@{ name = $tool.Name; command = $tool.Command; extension = $tool.Extension; version = $toolVersion }

$passwordFile = if ($KeyFile) { $KeyFile } else { $script:Config.Encryption.PasswordFile }
$password = Get-BaknretPassword -PasswordFile $passwordFile
$encryptAll = [bool]$script:Config.Encryption.Enabled
$showToolOutput = (-not $QuietTool) -and ($script:Config.ToolOutput -ne 'quiet')
$toolQuietArgument = if ($showToolOutput) { @() } else { @('-bso0', '-bsp0') }

$lines = Get-Content -LiteralPath $BackupListPath
$seenBaseNames = @{}
$processed = 0; $skipped = 0; $failed = 0; $planned = 0
$failures = @()
$freeSpaceGB = Get-BaknretFreeSpaceGB -Path $BackupDir
if ($freeSpaceGB -ge 0) {
    Write-Log ("备份目录所在卷剩余空间：{0} GB" -f $freeSpaceGB)
    if ($freeSpaceGB -lt $script:Config.MinFreeSpaceGB) {
        Write-Log ("剩余空间低于阈值 {0} GB，大条目可能失败" -f $script:Config.MinFreeSpaceGB) -Level WARN
    }
}

function Test-ItemSelected {
    param([string]$DisplayPath, [string]$BaseName)
    if ($Only.Count -gt 0) {
        $matched = $false
        foreach ($pattern in $Only) {
            if ($DisplayPath -like $pattern -or $BaseName -like $pattern) { $matched = $true; break }
        }
        if (-not $matched) { return $false }
    }
    foreach ($pattern in $Skip) {
        if ($DisplayPath -like $pattern -or $BaseName -like $pattern) { return $false }
    }
    return $true
}

function New-ItemRecord {
    param([string]$BaseName, [string]$Source, [string]$ResolvedSource, [string]$Phase)
    return [ordered]@{
        baseName       = $BaseName
        source         = $Source
        resolvedSource = $ResolvedSource
        roots          = @()
        catalog        = $null
        archive        = $null
        action         = $null
        reason         = $null
        phase          = $Phase
        attemptedAt    = (Get-Date).ToString('o')
        finishedAt     = $null
        durationSec    = $null
        exitCode       = $null
        verified       = $false
        warnings       = $false
        attemptWarnings = $false
        encrypted      = $false
        sourceFiles    = $null
        sourceBytes    = $null
        archiveBytes   = $null
        sha256         = $null
        lastSuccessAt  = $null
        successCount   = 0
        failCount      = 0
    }
}

function Save-ItemRecord {
    param($Record, [string]$Action, [string]$Reason, [bool]$ArchiveWarnings = $false)

    $previous = $null
    if ($manifest.items.Contains($Record.baseName)) { $previous = $manifest.items[$Record.baseName] }

    $Record.action = $Action
    $Record.reason = $Reason
    $Record.finishedAt = (Get-Date).ToString('o')

    # warnings 描述的是"当前在位的归档"，不是"这次尝试"。
    # 只有真正换掉了归档才更新它；否则沿用上一条记录，
    # 否则"因为不完整而保留旧归档"之后，下一次就失去保护了。
    if ($Action -eq 'backed-up') {
        $Record.warnings = $ArchiveWarnings
    } elseif ($previous -and ($previous.PSObject.Properties.Name -contains 'warnings')) {
        $Record.warnings = [bool]$previous.warnings
    }

    if ($previous) {
        if ($previous.PSObject.Properties.Name -contains 'lastSuccessAt') { $Record.lastSuccessAt = $previous.lastSuccessAt }
        if ($previous.PSObject.Properties.Name -contains 'successCount') { $Record.successCount = [int]$previous.successCount }
        if ($previous.PSObject.Properties.Name -contains 'failCount') { $Record.failCount = [int]$previous.failCount }
    }

    if ($Action -eq 'backed-up') {
        $Record.lastSuccessAt = $Record.finishedAt
        $Record.successCount = [int]$Record.successCount + 1
    } elseif ($Action -eq 'failed') {
        $Record.failCount = [int]$Record.failCount + 1
    }

    $manifest.items[$Record.baseName] = $Record
    return $Record
}

# 压缩 + 校验 + 原子替换；返回 @{ Ok; ExitCode; Warnings; Reason }
#
# $SourceGroups 支持"一个软件包含多个目录"：每个元素是
# @{ ParentDir; RelativePaths; Label }。7z/RAR 对同一归档多次 `a` 会把内容并入，
# 所以按父目录分组、逐组追加，归档里每个目录仍保留自己的名字与层级。
function Invoke-BackupItem {
    param(
        [Parameter(Mandatory = $true)][array]$SourceGroups,
        [Parameter(Mandatory = $true)][string]$FinalPath,
        [string[]]$ExcludePatterns,
        [switch]$UseEncryption,
        [switch]$ProtectPrevious,
        [switch]$AcceptWarnings
    )

    $tempPath = "$FinalPath.tmp$($tool.Extension)"
    if (Test-Path -LiteralPath $tempPath) { Remove-Item -LiteralPath $tempPath -Force -ErrorAction SilentlyContinue }

    $warnings = $false
    $lastExitCode = 0
    $lastParentDir = $null

    try {
        if ($SourceGroups.Count -eq 0) {
            return [pscustomobject]@{ Ok = $false; ExitCode = $null; Warnings = $false; Reason = '没有可打包的源目录' }
        }

        $groupIndex = 0
        foreach ($group in $SourceGroups) {
            $groupIndex++
            $parentDir = $group.ParentDir
            $relativePaths = @($group.RelativePaths)
            if ($relativePaths.Count -eq 0) { continue }
            $lastParentDir = $parentDir

            # 排除模式的**前缀用这一组的源目录名**（归档里就是这个层级）。
            $prefixName = if ($group.Label) { $group.Label } else { Split-Path -Path $relativePaths[0] -Leaf }
            $excludeArgument = Get-ArchiveExcludeArgument -ItemName $prefixName -Patterns $ExcludePatterns

            if ($tool.Name -eq '7z') {
                $probePath = "$($parentDir.TrimEnd('\'))\$($relativePaths[0])"
                $optimized = Get-Optimized7zArgument -SourcePath $probePath -Level $script:Config.CompressionLevel
                $argument = @($optimized.Argument) + $toolQuietArgument + $excludeArgument

                if ($UseEncryption) {
                    if (-not $password) {
                        return [pscustomobject]@{ Ok = $false; ExitCode = $null; Warnings = $false; Reason = '需要加密但取不到口令（见 README「加密」）' }
                    }
                    $argument += "-p$password"
                    if ($script:Config.Encryption.EncryptHeaders) { $argument += '-mhe=on' }
                }

                $argument += $tempPath
                foreach ($relative in $relativePaths) { $argument += $relative }

                $exitCode = Invoke-ExternalCommand -FilePath $tool.Command -ArgumentList $argument -WorkingDirectory $parentDir
                $lastExitCode = $exitCode
                # 7z: 0 成功；1 警告（有文件读不到或跳过）；2 及以上为失败
                if ($exitCode -ne 0 -and $exitCode -ne 1) {
                    return [pscustomobject]@{ Ok = $false; ExitCode = $exitCode; Warnings = $warnings; Reason = "第 $groupIndex 组（$prefixName）压缩工具退出码 $exitCode" }
                }
                if ($exitCode -eq 1) { $warnings = $true }
            }
            elseif ($tool.Name -eq 'RAR') {
                $argument = @('a', '-m5', '-idp', '-idn') + $toolQuietArgument + $excludeArgument
                if ($UseEncryption) {
                    if (-not $password) {
                        return [pscustomobject]@{ Ok = $false; ExitCode = $null; Warnings = $false; Reason = '需要加密但取不到口令' }
                    }
                    $argument += "-p$password"
                }
                $argument += $tempPath
                foreach ($relative in $relativePaths) { $argument += $relative }

                $exitCode = Invoke-ExternalCommand -FilePath $tool.Command -ArgumentList $argument -WorkingDirectory $parentDir
                $lastExitCode = $exitCode
                if ($exitCode -ne 0) {
                    return [pscustomobject]@{ Ok = $false; ExitCode = $exitCode; Warnings = $warnings; Reason = "第 $groupIndex 组（$prefixName）压缩工具退出码 $exitCode" }
                }
            }
            else {
                if ($UseEncryption) {
                    return [pscustomobject]@{ Ok = $false; ExitCode = $null; Warnings = $false; Reason = '内置 ZIP 不支持加密，请改用 7z 或去掉 encrypt 标记' }
                }
                # Compress-Archive 不能追加；多组时逐组重打（先把已有临时归档解开再合并会让代码复杂得多，
                # 而 ZIP 本来就是降级路径，这里只保证内容完整）
                $fullPaths = @($relativePaths | ForEach-Object { Join-Path $parentDir $_ })
                if ($groupIndex -gt 1 -and (Test-Path -LiteralPath $tempPath)) {
                    $staging = Join-Path $env:TEMP ("bnr-zip-" + [guid]::NewGuid().ToString('N'))
                    New-Item -ItemType Directory -Path $staging -Force | Out-Null
                    try {
                        Expand-Archive -LiteralPath $tempPath -DestinationPath $staging -Force
                        $fullPaths += @(Get-ChildItem -LiteralPath $staging -Force | Select-Object -ExpandProperty FullName)
                        Compress-Archive -Path $fullPaths -DestinationPath $tempPath -CompressionLevel Optimal -Force
                    } finally {
                        Remove-Item -LiteralPath $staging -Recurse -Force -ErrorAction SilentlyContinue
                    }
                } else {
                    Compress-Archive -Path $fullPaths -DestinationPath $tempPath -CompressionLevel Optimal -Force
                }
            }
        }

        if (-not (Test-Path -LiteralPath $tempPath)) {
            return [pscustomobject]@{ Ok = $false; ExitCode = $null; Warnings = $false; Reason = '压缩结束但没有生成临时归档' }
        }

        # 校验：确认归档可读且内容 CRC 正确
        if ($script:Config.VerifyArchive -and $tool.Name -eq '7z') {
            $verifyArgument = @('t', '-bso0', '-bsp0')
            if ($UseEncryption -and $password) { $verifyArgument += "-p$password" }
            $verifyArgument += $tempPath

            $verifyCode = Invoke-ExternalCommand -FilePath $tool.Command -ArgumentList $verifyArgument -WorkingDirectory $lastParentDir
            if ($verifyCode -ne 0) {
                Remove-Item -LiteralPath $tempPath -Force -ErrorAction SilentlyContinue
                return [pscustomobject]@{ Ok = $false; ExitCode = $verifyCode; Warnings = $false; Reason = "归档校验失败（7z t 退出码 $verifyCode），已丢弃临时文件" }
            }
            Write-Log '归档校验通过（7z t）' -Level DEBUG

            # 多目录时确认每个目录都真的进了归档：7z 的"警告"可能只体现在某一组里
            if ($SourceGroups.Count -gt 1) {
                $listed = @(Get-ArchiveTopLevelNames -ArchivePath $tempPath -SevenZip $tool.Command -Password $(if ($UseEncryption) { $password } else { $null }))
                if ($listed.Count -gt 0) {
                    $expected = @($SourceGroups | ForEach-Object { Split-Path -Path $_.RelativePaths[0] -Leaf })
                    $absent = @($expected | Where-Object { $_ -notin $listed })
                    if ($absent.Count -gt 0) {
                        Remove-Item -LiteralPath $tempPath -Force -ErrorAction SilentlyContinue
                        return [pscustomobject]@{ Ok = $false; ExitCode = $lastExitCode; Warnings = $true; Reason = ("归档缺少这些目录：{0}（归档内实际有：{1}）" -f ($absent -join '、'), ($listed -join '、')) }
                    }
                }
            }
        }

        # 关键保护：压缩工具报了警告（通常是有文件被占用读不到）时，
        # 新归档是**不完整**的。用不完整归档覆盖已有的完整归档 = 静默丢数据。
        # 实测：Edge 运行时备份，118 个文件读不到，其中包含 Login Data（密码）、
        # Cookies、History、Web Data —— 恰恰是最不可再生的那部分。
        if ($warnings -and $ProtectPrevious -and -not $AcceptWarnings) {
            Remove-Item -LiteralPath $tempPath -Force -ErrorAction SilentlyContinue
            return [pscustomobject]@{
                Ok       = $false
                ExitCode = $lastExitCode
                Warnings = $true
                Reason   = '压缩工具报告有文件被占用而读不到，新归档不完整。为避免覆盖现有的完整归档已保留旧归档；请关闭占用该目录的程序后重跑，或确认可以接受后用 -AcceptWarnings 强制覆盖'
            }
        }

        Move-BaknretArchiveIntoPlace -TempPath $tempPath -DestinationPath $FinalPath
        return [pscustomobject]@{ Ok = $true; ExitCode = 0; Warnings = $warnings; Reason = $null }
    } catch {
        if (Test-Path -LiteralPath $tempPath) {
            Remove-Item -LiteralPath $tempPath -Force -ErrorAction SilentlyContinue
        }
        return [pscustomobject]@{ Ok = $false; ExitCode = $null; Warnings = $false; Reason = "$_" }
    }
}

# ============================================================================
# 备份前空间预估（只读，不写任何东西）
# ============================================================================
# 只做一件事：动手之前告诉用户"这次大概要写多少、盘够不够"。
# 不做更复杂的占用控制 —— 真正拦住某个条目的是主循环里的逐条目守卫。
#
# 模型（按清单顺序模拟一遍）：
#   * 每个要重打的条目会先写一份**临时**归档，这时旧归档还在，所以那一刻占用的
#     是"当前累计净增量 + 本次预估"；
#   * 原子替换之后，本次净增量 = 预估 - 现有归档大小（换成更小的归档会把空间还回来）。
#   于是：峰值新增 = max_i( 第 i 项之前的累计净增量 + 第 i 项的预估大小 )。
$spacePlan = @()
$spaceSkipped = 0
$spaceNoSource = 0

foreach ($planLine in $lines) {
    $planItem = ConvertFrom-BackupListLine -Line $planLine
    if (-not $planItem) { continue }

    $planDisplayPath = $planItem.Path
    $planResolved = Resolve-BackupEntry -Entry $planItem -CatalogPath $catalogPath -MaxDepth $script:Config.CatalogMaxDepth
    if (-not $planResolved.BaseName) { continue }
    if (-not (Test-ItemSelected -DisplayPath $planDisplayPath -BaseName $planResolved.BaseName)) { continue }
    if ($planResolved.Blocking) { continue }

    $planSources = @($planResolved.Sources | Where-Object { Test-Path -LiteralPath $_.SourcePath })
    if ($planSources.Count -eq 0) { $spaceNoSource++; continue }

    $planSourceBytes = [int64]0
    $planSourceFiles = 0
    $planLatest = $null
    foreach ($planSource in $planSources) {
        $planSummary = Get-FolderSummary -FolderPath $planSource.SourcePath
        $planSourceBytes += [int64]$planSummary.TotalSize
        $planSourceFiles += [int]$planSummary.FileCount
        if ($planSummary.LatestModifiedTime -and (-not $planLatest -or $planSummary.LatestModifiedTime -gt $planLatest)) {
            $planLatest = $planSummary.LatestModifiedTime
        }
    }

    $planArchiveName = $planResolved.BaseName + $tool.Extension
    $planArchivePath = Join-Path $BackupDir $planArchiveName
    $planExistingItem = if (Test-Path -LiteralPath $planArchivePath) { Get-Item -LiteralPath $planArchivePath } else { $null }
    $planExistingBytes = if ($planExistingItem) { [int64]$planExistingItem.Length } else { [int64]0 }

    # 与主循环同一套判断：源没更新就不会重打
    if (-not $Force -and $planExistingItem -and $planLatest -and $planLatest -le $planExistingItem.LastWriteTime) {
        $spaceSkipped++
        continue
    }

    $planEstimate = if ($planExistingBytes -gt 0) {
        [int64][math]::Min([double]$planSourceBytes, [double]$planExistingBytes * 1.3)
    } else {
        # 没有历史归档可比时按"完全不压缩"的悲观值估，宁可报多不报少
        $planSourceBytes
    }

    $spacePlan += [pscustomobject]@{
        Name        = $planResolved.BaseName
        Source      = $planDisplayPath
        Files       = $planSourceFiles
        SourceBytes = $planSourceBytes
        Existing    = $planExistingBytes
        Estimate    = $planEstimate
    }
}

$freeNowGB = Get-BaknretFreeSpaceGB -Path $BackupDir

if ($spacePlan.Count -eq 0) {
    Write-Log '备份前空间预估：本次没有需要重打的条目（源未更新或源不存在），不会写入新归档' -Level INFO
} else {
    $spacePeak = [double]0
    $spaceCumulative = [double]0
    foreach ($plan in $spacePlan) {
        $spacePeak = [math]::Max($spacePeak, $spaceCumulative + $plan.Estimate)
        $spaceCumulative += ($plan.Estimate - $plan.Existing)
    }
    $peakGB = $spacePeak / 1GB
    $netGB = $spaceCumulative / 1GB
    $estimateGB = ((($spacePlan | Measure-Object -Property Estimate -Sum).Sum)) / 1GB
    $existingGB = ((($spacePlan | Measure-Object -Property Existing -Sum).Sum)) / 1GB

    Write-Log '==== 备份前空间预估（只读）====' -Level INFO
    Write-Log ("  目标卷可用空间：{0} GB" -f $freeNowGB)
    Write-Log ("  本次要重打 {0} 个条目（另有 {1} 个源未更新会跳过、{2} 个源不存在）" -f $spacePlan.Count, $spaceSkipped, $spaceNoSource)
    Write-Log ("  新归档合计约 {0} GB；其中会替换掉的旧归档 {1} GB" -f [math]::Round($estimateGB, 2), [math]::Round($existingGB, 2))

    foreach ($plan in ($spacePlan | Sort-Object Estimate -Descending | Select-Object -First 15)) {
        Write-Log ("    - {0,-22} 源 {1,8:N1} MB / {2,6} 文件   现有 {3,7:N1} MB   预估 {4,7:N1} MB" -f `
                $plan.Name, ($plan.SourceBytes / 1MB), $plan.Files, ($plan.Existing / 1MB), ($plan.Estimate / 1MB))
    }
    if ($spacePlan.Count -gt 15) {
        Write-Log ("    …… 另有 {0} 个条目未逐条列出" -f ($spacePlan.Count - 15))
    }

    Write-Log ("  预计峰值新增占用：{0} GB（全程净增量 {1} GB）" -f [math]::Round($peakGB, 2), [math]::Round($netGB, 2))

    if ($freeNowGB -lt 0) {
        Write-Log '  结论：读不到目标卷可用空间，请自行确认是否够用' -Level WARN
    } elseif ($peakGB -le $freeNowGB) {
        Write-Log ("  结论：空间足够（预计用 {0} GB / 可用 {1} GB）" -f [math]::Round($peakGB, 2), $freeNowGB) -Level INFO
    } else {
        Write-Log ("  结论：空间可能不够！预计需要 {0} GB，可用只有 {1} GB，差 {2} GB" -f `
                [math]::Round($peakGB, 2), $freeNowGB, [math]::Round($peakGB - $freeNowGB, 2)) -Level WARN
        Write-Log '    仍会继续执行：真正放不下的条目会被逐条目守卫跳过。建议先腾空间，或用 -Only / -Skip 分批备份。' -Level WARN
    }
    Write-Log '============================' -Level INFO
}

# ============================================================================
# 主流程
# ============================================================================

foreach ($line in $lines) {
    $item = ConvertFrom-BackupListLine -Line $line
    if (-not $item) { continue }

    $displayPath = $item.Path
    $resolved = Resolve-BackupEntry -Entry $item -CatalogPath $catalogPath -MaxDepth $script:Config.CatalogMaxDepth

    if (-not $resolved.BaseName) {
        $record = New-ItemRecord -BaseName ('raw:' + $displayPath) -Source $displayPath -ResolvedSource $displayPath -Phase 'parse'
        Save-ItemRecord -Record $record -Action 'failed' -Reason '无法生成归档名' | Out-Null
        $failed++; $failures += $displayPath
        continue
    }

    $baseName = $resolved.BaseName
    $sourcePath = [Environment]::ExpandEnvironmentVariables($displayPath)

    if (-not (Test-ItemSelected -DisplayPath $displayPath -BaseName $baseName)) {
        Write-Log "跳过（未选中）: $displayPath" -Level DEBUG
        continue
    }

    $record = New-ItemRecord -BaseName $baseName -Source $displayPath -ResolvedSource $sourcePath -Phase 'backup'
    $record.archive = $baseName + $tool.Extension
    if ($resolved.CatalogEntry) { $record.catalog = $resolved.CatalogEntry.Path }
    $finalPath = Join-Path $BackupDir $record.archive

    # root= 在 README 里被列为可用标记，但归档内的根目录实际上始终是源目录名
    # （见 README「设计取舍」：不套一层软件名目录）。7z 命令行也没有"入库时改名"
    # 的能力，所以这里明确告警而不是让它静默失效——静默失效正是本次重构要消灭的东西。
    if (@($item.Flags | Where-Object { $_ -like 'root=*' }).Count -gt 0) {
        Write-Log "警告: $displayPath 使用了 root= 标记，该功能尚未实现（归档内的根目录始终是源目录名），本次忽略" -Level WARN
    }

    # 备份列表里写重了会生成两个同名归档，互相覆盖 —— 直接报错，不猜。
    if ($seenBaseNames.ContainsKey($baseName)) {
        $reason = "归档名 '$baseName' 与清单中的 '$($seenBaseNames[$baseName])' 重复（由 '$displayPath' 生成），两者会互相覆盖"
        Write-Log "失败: $displayPath，$reason" -Level ERROR
        Save-ItemRecord -Record $record -Action 'failed' -Reason $reason | Out-Null
        $failed++; $failures += $displayPath
        continue
    }
    $seenBaseNames[$baseName] = $displayPath

    # 归档内顶层同名冲突：明确失败，绝不把两个目录静默搅进同一棵树
    if ($resolved.Blocking) {
        Write-Log "失败: $displayPath，$($resolved.Blocking)" -Level ERROR
        Save-ItemRecord -Record $record -Action 'failed' -Reason $resolved.Blocking | Out-Null
        $failed++; $failures += $displayPath
        continue
    }

    # 动手之前先把"这条会打包哪些目录、排除了什么、为什么"讲清楚
    Write-BackupEntryPlan -Resolved $resolved -DisplayPath $displayPath `
        -ListExcludes @($item.ExcludePatterns) -ConfigExcludes @($script:Config.DefaultExcludes) `
        -Comment $item.Comment

    # Sources 为空 = 解析不出任何源（名录里没这个软件名、或路径拆不出父/子级）。
    # 注意不能用 $resolved.Error 判断：名录里的路径不存在时 Error 有值，
    # 但 Sources 是给出的（恢复端要靠它把内容还原回原位），备份端由下面的
    # 存在性检查统一处理。
    if ($resolved.Sources.Count -eq 0) {
        $reason = if ($resolved.Error) { $resolved.Error } else { '解析不出任何源路径' }
        Write-Log "跳过: $displayPath，$reason" -Level WARN
        Save-ItemRecord -Record $record -Action 'missing-source' -Reason $reason | Out-Null
        $skipped++
        continue
    }

    # 源存在性检查必须在 Get-FolderSummary / Get-Item 之前：
    # 两者对不存在的路径要么抛异常、要么返回会误导判断的空摘要。
    # 注意不能用 Join-Path 探测：目标盘符不存在时它会直接抛异常。
    # 源路径存在性以 SourcePath 为准：RelativePaths 是"归档里的名字"，
    # 目前两者一致，但 SourcePath 才是磁盘上的真实位置。
    $expectedRoots = 0
    $missingRoots = @()
    foreach ($source in $resolved.Sources) {
        $expectedRoots++
        if (-not (Test-Path -LiteralPath $source.SourcePath)) { $missingRoots += $source.SourcePath }
    }

    if ($missingRoots.Count -ge $expectedRoots) {
        Write-Log "跳过: $displayPath，源路径不存在" -Level WARN
        Save-ItemRecord -Record $record -Action 'missing-source' -Reason ('源路径不存在：' + ($missingRoots -join '；')) | Out-Null
        $skipped++
        continue
    }

    if ($missingRoots.Count -gt 0) {
        Write-Log ("警告: {0} 有 {1} 个源路径不存在，本次只备份存在的部分：{2}" -f $displayPath, $missingRoots.Count, ($missingRoots -join '；')) -Level WARN
    }

    # 归档里只放真实存在的源
    $liveSources = @()
    foreach ($source in $resolved.Sources) {
        if (Test-Path -LiteralPath $source.SourcePath) {
            $liveSources += [pscustomobject]@{
                RootName      = $source.RootName
                ParentDir     = $source.ParentDir
                RelativePaths = @($source.RelativePaths)
                SourcePath    = $source.SourcePath
                Description   = $source.Description
                Origin        = $source.Origin
            }
        }
    }

    # 归档内的顶层条目名 = 每个**真实存在**的源在归档里的第一层名字，也就是源目录
    # （或源文件）自己的名字。刻意不用 $resolved.Sources[].RootName：那套"归档内套一层
    # 软件名"的设想已按设计取舍放弃，实际布局始终是 <源目录名>\...。
    # 这里记录可核对的事实，之前写成软件名会让 Edge（实际是 "User Data"）之类的条目对不上。
    $record.roots = @($liveSources | ForEach-Object {
            $_.RelativePaths | ForEach-Object { ($_ -split '[\\/]')[0] }
        } | Select-Object -Unique)

    $primarySource = $liveSources[0].SourcePath
    $parentDir = $liveSources[0].ParentDir
    # 排除模式的前缀始终用**源目录名**（归档里就是这个层级）
    $itemName = Split-Path -Path $primarySource -Leaf

    if (-not $parentDir -or -not $itemName) {
        Write-Log "跳过: $displayPath，无法处理根目录" -Level WARN
        Save-ItemRecord -Record $record -Action 'invalid-path' -Reason '无法拆出父目录或末级名' | Out-Null
        $skipped++
        continue
    }

    $summary = Get-FolderSummary -FolderPath $primarySource
    foreach ($source in $liveSources[1..($liveSources.Count - 1)]) {
        $extra = Get-FolderSummary -FolderPath $source.SourcePath
        $summary.FileCount += $extra.FileCount
        $summary.TotalSize += $extra.TotalSize
        if ($extra.LatestModifiedTime -and $extra.LatestModifiedTime -gt $summary.LatestModifiedTime) {
            $summary.LatestModifiedTime = $extra.LatestModifiedTime
        }
    }
    $record.sourceFiles = $summary.FileCount
    $record.sourceBytes = $summary.TotalSize

    $archiveExists = Test-Path -LiteralPath $finalPath
    $archiveItem = if ($archiveExists) { Get-Item -LiteralPath $finalPath } else { $null }

    Write-Log ("开始备份: {0} -> {1}（{2} 个文件，{3} MB）" -f $displayPath, $record.archive, $summary.FileCount, [math]::Round(($summary.TotalSize / 1MB), 2))

    # 空目录时 Get-FolderSummary 拿不到任何条目，回退到源自身的修改时间
    # （源路径上面已经确认存在，这里的 Get-Item 不会再抛异常）
    $sourceLatest = $summary.LatestModifiedTime
    if (-not $sourceLatest) {
        $sourceLatest = (Get-Item -LiteralPath $primarySource -Force).LastWriteTime
    }

    if (-not $Force -and $archiveItem -and $sourceLatest -and $sourceLatest -le $archiveItem.LastWriteTime) {
        Write-Log "跳过: $displayPath，源目录未更新" -Level INFO
        $record.archiveBytes = $archiveItem.Length
        Save-ItemRecord -Record $record -Action 'skip-unchanged' -Reason ('源最新修改时间 {0} 不晚于归档时间 {1}' -f $sourceLatest, $archiveItem.LastWriteTime) | Out-Null
        $skipped++
        continue
    }

    # 空间守卫：临时归档与正式归档会同时存在，因此按"新归档预估大小"要求剩余空间
    $estimatedGB = $summary.TotalSize / 1GB
    if ($archiveItem) {
        $archiveGB = $archiveItem.Length / 1GB
        $estimatedGB = [math]::Min($estimatedGB, $archiveGB * 1.3)
    }
    $freeSpaceGB = Get-BaknretFreeSpaceGB -Path $BackupDir
    if ($freeSpaceGB -ge 0 -and $estimatedGB -gt 0 -and $freeSpaceGB -lt $estimatedGB) {
        $reason = ('剩余空间 {0} GB 不足以写入预估 {1} GB 的新归档' -f $freeSpaceGB, [math]::Round($estimatedGB, 2))
        Write-Log "失败: $displayPath，$reason" -Level ERROR
        Save-ItemRecord -Record $record -Action 'failed' -Reason $reason | Out-Null
        $failed++; $failures += $displayPath
        continue
    }

    if ($DryRun) {
        Write-Log ("[试运行] 将打包 {0} -> {1}" -f $sourcePath, $finalPath) -Level INFO
        $record.reason = '试运行，未执行压缩'
        Save-ItemRecord -Record $record -Action 'planned' -Reason '试运行，未执行压缩' | Out-Null
        $planned++
        continue
    }

    $useEncryption = $encryptAll -or ($item.Flags -contains 'encrypt')
    $record.encrypted = [bool]$useEncryption
    $startedAt = Get-Date
    $record.attemptedAt = $startedAt.ToString('o')

    # 配置里的全局排除 + 本条目的排除
    $effectiveExcludes = @($script:Config.DefaultExcludes) + @($item.ExcludePatterns)

    # 只有在"现有归档是完整的"时才值得保护它。没有 manifest 记录
    # （本次重构之前留下的归档）时按完整处理——宁可保守。
    $protectPrevious = [bool]$archiveExists
    if ($archiveExists -and $manifest.items.Contains($baseName)) {
        $previousRecord = $manifest.items[$baseName]
        if (($previousRecord.PSObject.Properties.Name -contains 'warnings') -and $previousRecord.warnings) {
            $protectPrevious = $false
        }
    }

    # 多目录：每个源组各带自己的父目录与相对名。7z 会对同一归档逐组追加。
    # Label 刻意留空：排除模式的前缀必须是**归档里的那一层名字**，也就是源目录名
    # （归档内布局是 `<源目录名>\...`）。若把软件名当 Label 传下去，
    # 排除模式就会变成 `软件名\skip.bin`，与实际路径对不上而静默失效。
    $sourceGroups = @($liveSources | ForEach-Object {
            [pscustomobject]@{
                ParentDir     = $_.ParentDir
                RelativePaths = @($_.RelativePaths)
                Label         = $null
            }
        })

    $result = Invoke-BackupItem -SourceGroups $sourceGroups `
        -FinalPath $finalPath -ExcludePatterns $effectiveExcludes -UseEncryption:$useEncryption `
        -ProtectPrevious:$protectPrevious -AcceptWarnings:$AcceptWarnings

    $record.exitCode = $result.ExitCode
    $record.attemptWarnings = [bool]$result.Warnings
    $record.verified = [bool]$result.Ok
    $record.durationSec = [math]::Round(((Get-Date) - $startedAt).TotalSeconds, 1)

    if (-not $result.Ok) {
        Write-Log "备份失败: $displayPath，$($result.Reason)" -Level ERROR
        Save-ItemRecord -Record $record -Action 'failed' -Reason $result.Reason | Out-Null
        $failed++; $failures += $displayPath
        continue
    }

    $written = Get-Item -LiteralPath $finalPath
    $record.archiveBytes = $written.Length
    if ($result.Warnings) {
        Write-Log "备份成功（压缩工具报告了警告，可能有文件被占用而没打进归档）: $displayPath" -Level WARN
        Write-Log '  该归档在 manifest 里标记为 warnings=true；如果以后现有归档是完整的，会拒绝被它覆盖' -Level WARN
    } else {
        Write-Log "备份成功: $baseName" -Level INFO
    }

    if ($Hash -or $script:Config.ComputeHash) {
        $record.sha256 = (Get-FileHash -LiteralPath $finalPath -Algorithm SHA256).Hash
        Write-Log "SHA256: $($record.sha256)" -Level DEBUG
    }

    if ($Snapshot -or $script:Config.Snapshot.Enabled) {
        $stamp = Get-Date -Format 'yyyyMMdd-HHmmss'
        $target = Join-Path (Join-Path $snapshotDir $stamp) $record.archive
        $targetDir = Split-Path -Parent $target
        if (-not (Test-Path -LiteralPath $targetDir)) { New-Item -ItemType Directory -Path $targetDir -Force | Out-Null }
        Copy-Item -LiteralPath $finalPath -Destination $target -Force
        Write-Log "已留存快照: $target" -Level INFO
    }

    Save-ItemRecord -Record $record -Action 'backed-up' -Reason $null -ArchiveWarnings $result.Warnings | Out-Null
    $processed++
}

# ============================================================================
# 收尾
# ============================================================================

if ($DryRun) {
    Write-Log '试运行：manifest 与归档都不会被写入' -Level INFO
} else {
    # manifest 里写了 archive 的记录，磁盘上就必须真有那个文件
    $clearedArchiveFields = Sync-BaknretManifestArchive -Manifest $manifest -BackupDir $BackupDir
    if ($clearedArchiveFields.Count -gt 0) {
        Write-Log ("已清空 {0} 条记录里指向不存在归档的 archive 字段：{1}" -f $clearedArchiveFields.Count, ($clearedArchiveFields -join '、')) -Level WARN
    }

    Write-BaknretManifest -Path $manifestPath -Manifest $manifest | Out-Null
    Write-Log "manifest 已更新：$manifestPath" -Level DEBUG
}

# 孤儿归档审计：磁盘上有、但**当前清单里任何条目都不指向**的归档。
# Restore.ps1 是按清单条目去找归档的，所以孤儿是**恢复不到**的 —— 必须显式点名，
# 免得下次清理时把还有用的归档当垃圾删掉（重构前那个 2.8 GB 的归档就是这么成孤儿的）。
#
# 判据只用清单，**不能用 manifest**：manifest 会一直留着历史条目，
# 于是"从清单里删掉某个条目（或把它合并进另一个条目）"留下的归档会被历史记录遮住，
# 审计就永远不会报——那正是最需要报出来的情况。
# 只在整表运行时做：带 -Only/-Skip 时未选中的条目本来就不在 $seenBaseNames 里，
# 那种情况下报出来的全是假孤儿。
if (-not $DryRun -and $Only.Count -eq 0 -and $Skip.Count -eq 0) {
    $known = @{}
    foreach ($key in $seenBaseNames.Keys) { $known[$key] = $true }

    $orphanArchives = @(Get-ChildItem -LiteralPath $BackupDir -File -Force -ErrorAction SilentlyContinue |
        Where-Object { $_.Extension.ToLower() -in @('.7z', '.rar', '.zip', '.tar') -and -not $known.ContainsKey($_.BaseName) })

    if ($orphanArchives.Count -gt 0) {
        Write-Log ("发现 {0} 个孤儿归档（当前清单里没有任何条目指向，恢复不到，注意别误删）：" -f $orphanArchives.Count) -Level WARN
        foreach ($orphan in $orphanArchives) {
            $inManifest = $manifest.items.Contains($orphan.BaseName)
            Write-Log ("  - {0}（{1:N1} MB，{2}）{3}" -f $orphan.Name, ($orphan.Length / 1MB), $orphan.LastWriteTime, $(if ($inManifest) { '；manifest 里还留着它的历史记录，但清单里已经没有了' } else { '' })) -Level WARN
        }
    } else {
        Write-Log '孤儿归档审计：没有发现（所有归档都有清单条目指向）' -Level DEBUG
    }
}

if ($failures.Count -gt 0) {
    Write-Log '失败条目：' -Level ERROR
    foreach ($failure in $failures) { Write-Log "  - $failure" -Level ERROR }
}

$summaryText = "备份完成。成功: $processed, 跳过: $skipped, 失败: $failed"
if ($DryRun) { $summaryText += ", 试运行计划: $planned" }
Write-Log $summaryText -Level INFO

$logPath = Get-BaknretLogPath
if ($logPath) { Write-Log "日志已写入：$logPath" -Level INFO }
Stop-BaknretLog

if ($failed -gt 0) { exit 1 }
exit 0