<#
.SYNOPSIS
    按 BackupList.txt 执行恢复。

.DESCRIPTION
    与旧版相比的核心变化：

      1. 归档查找以 manifest.json 为准（按归档基础名索引），拿不到才退回
         "从文件名反推路径"。旧版只靠文件名反推，且用 -Filter "$baseName.*" 通配匹配，
         一旦解析出偏差，归档就变成谁都找不到的孤儿。
      2. 退出码可靠：三条解压分支（7z / RAR / tar）统一走 Invoke-ExternalCommand。
         旧版 tar 分支写成 `$LASTEXITCODE -ne 0 -and $proc.ExitCode -ne 0`，
         而 $LASTEXITCODE 是上一条原生命令的残留值，跟 Start-Process 无关，
         恰为 0 时会把解压失败吞掉并报成功。
      3. 支持 -WhatIf / -DryRun：恢复是会覆盖 E:\CodeSpace、Edge User Data 这种
         真实目录的破坏性操作，必须能先看清单再决定。
      4. 支持 -Only / -Skip 只恢复指定条目，-VerifyOnly 只校验不写盘。
      5. 结尾按失败数 exit。
#>

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

    [Parameter()]
    [string]$BackupDir,

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

    [Parameter()]
    [string]$KeyFile,

    [Parameter()]
    [string[]]$Only = @(),

    [Parameter()]
    [string[]]$Skip = @(),

    # 忽略"目标比归档新"的保护，强制解压
    [Parameter()]
    [switch]$Force,

    # 只打印计划，不解压（等价于 -WhatIf）
    [Parameter()]
    [switch]$DryRun,

    # 只对归档做 7z t 校验，不解压
    [Parameter()]
    [switch]$VerifyOnly
)

$ErrorActionPreference = 'Stop'

if ($DryRun) { $WhatIfPreference = $true }

# ============================================================================
# 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
$SupportedFormats = @('.7z', '.rar', '.zip', '.tar')

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
$catalogPath = Resolve-CatalogPath -Configured $script:Config.SoftwareCatalog -Root $PSScriptRoot
$manifestPath = Join-Path $BackupDir 'manifest.json'

$logPath = Start-BaknretLog -Directory $logDir -Prefix 'restore'
Write-Log "日志文件：$logPath"
Write-Log "备份目录：$BackupDir"
Write-Log ("软件名录：{0}{1}" -f $catalogPath, $(if (Test-Path -LiteralPath $catalogPath) { '' } else { '（不存在，将只支持字面路径）' }))
if ($WhatIfPreference) { Write-Log '试运行模式（-WhatIf / -DryRun）：不会写入任何文件' -Level WARN }

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
}

$passwordFile = if ($KeyFile) { $KeyFile } else { $script:Config.Encryption.PasswordFile }
$password = Get-BaknretPassword -PasswordFile $passwordFile

# ============================================================================
# 归档查找
# ============================================================================

function Find-ArchiveByBaseName {
    <#
    .SYNOPSIS
        按归档基础名精确定位归档文件。

    .DESCRIPTION
        旧版用 Get-ChildItem -Filter "$baseName.*"，-Filter 会做通配符解释，
        路径里含 `[` `]` 时会失配；这里改为精确比较 BaseName。
    #>
    param([string]$BaseName)

    $candidate = Get-ChildItem -LiteralPath $BackupDir -File -Force -ErrorAction SilentlyContinue |        Where-Object { $_.BaseName -eq $BaseName -and $_.Extension.ToLower() -in $SupportedFormats } |
        Select-Object -First 1
    return $candidate
}

function Get-ArchiveForEntry {
    param($Entry, $Manifest)

    if ($Manifest -and $Manifest.items.Contains($Entry.baseName)) {
        $record = $Manifest.items[$Entry.baseName]
        $archiveName = $null
        if ($record.PSObject.Properties.Name -contains 'archive') { $archiveName = $record.archive }
        if ($archiveName) {
            $path = Join-Path $BackupDir $archiveName
            if (Test-Path -LiteralPath $path) {
                return [pscustomobject]@{ File = (Get-Item -LiteralPath $path); Source = 'manifest'; Record = $record }
            }
            Write-Log "manifest 记录的归档不存在，回退按文件名查找：$archiveName" -Level WARN
        }
    }

    $fallback = Find-ArchiveByBaseName -BaseName $Entry.baseName
    if ($fallback) {
        $record = $null
        if ($Manifest -and $Manifest.items.Contains($Entry.baseName)) { $record = $Manifest.items[$Entry.baseName] }
        return [pscustomobject]@{ File = $fallback; Source = 'filename'; Record = $record }
    }

    return $null
}

function Get-7zExecutable {
    <# .SYNOPSIS 定位 7z.exe（PATH 优先，其次是常见安装位置）。 #>
    $sevenZip = Get-Command 7z -ErrorAction SilentlyContinue | Select-Object -First 1 -ExpandProperty Source
    if (-not $sevenZip) {
        $candidates = @(
            (Join-Path $env:ProgramFiles '7-Zip\7z.exe'),
            (Join-Path ${env:ProgramFiles(x86)} '7-Zip\7z.exe')
        )
        $sevenZip = $candidates | Where-Object { $_ -and (Test-Path -LiteralPath $_) } | Select-Object -First 1
    }
    return $sevenZip
}

function Invoke-Extraction {
    param([object]$ArchiveFile, [string]$DestinationPath, [string]$RelativePath)

    $extension = $ArchiveFile.Extension.ToLower()
    $destParent = Split-Path -Path $DestinationPath -Parent

    if (-not (Test-Path -LiteralPath $destParent)) {
        New-Item -ItemType Directory -Path $destParent -Force | Out-Null
    }

    # 归档布局与历史保持一致：顶层就是**源目录名**（软件名只用于归档文件名）。
    # 一个条目可能打包了好几个目录（软件名录里的数组写法 / `:+` 追加），
    # 所以**不能整包往每个目标里倒** —— 那会把兄弟目录也复制到不相干的父目录下。
    # 这里只解出该目标自己那棵子树（$RelativePath），其余不动。
    $sevenZip = Get-7zExecutable
    if ($sevenZip) {
        Write-Log '使用 7z 解压' -Level DEBUG
        $argument = @('x', '-bsp2', '-y', "-o$destParent")
        if ($password) { $argument += "-p$password" }
        $argument += $ArchiveFile.FullName
        if ($RelativePath) { $argument += $RelativePath }

        $exitCode = Invoke-ExternalCommand -FilePath $sevenZip -ArgumentList $argument
        if ($exitCode -ne 0) { throw "7z 解压失败（退出码：$exitCode）" }
        return $true
    }

    switch ($extension) {
        '.rar' {
            $rarExe = Get-Command rar, unrar -ErrorAction SilentlyContinue | Select-Object -First 1 -ExpandProperty Source
            if (-not $rarExe) { throw '未找到 RAR 工具' }
            Write-Log '使用 RAR 解压' -Level DEBUG
            $argument = @('x', '-idp', '-idn', '-y', $ArchiveFile.FullName, "$destParent\")
            if ($RelativePath) { $argument += $RelativePath }
            $exitCode = Invoke-ExternalCommand -FilePath $rarExe -ArgumentList $argument
            if ($exitCode -ne 0) { throw "RAR 解压失败（退出码：$exitCode）" }
        }
        '.zip' {
            Write-Log '使用内置 ZIP 解压' -Level DEBUG
            if ($RelativePath) {
                Write-Log "内置 ZIP 不支持只解子树，将整包解压（$RelativePath）" -Level WARN
            }
            Expand-Archive -LiteralPath $ArchiveFile.FullName -DestinationPath $destParent -Force
        }
        '.tar' {
            $tarExe = Get-Command tar -ErrorAction SilentlyContinue | Select-Object -First 1 -ExpandProperty Source
            if (-not $tarExe) { throw '未找到 TAR 工具' }
            Write-Log '使用 TAR 解压' -Level DEBUG
            $argument = @('-xf', $ArchiveFile.FullName, '-C', $destParent)
            if ($RelativePath) { $argument += $RelativePath }
            $exitCode = Invoke-ExternalCommand -FilePath $tarExe -ArgumentList $argument
            if ($exitCode -ne 0) { throw "TAR 解压失败（退出码：$exitCode）" }
        }
        default { throw "不支持的文件格式：$extension" }
    }
    return $true
}

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

if (-not (Test-Path -LiteralPath $BackupDir)) {
    Write-Log "备份目录不存在: $BackupDir" -Level ERROR
    Stop-BaknretLog
    exit 1
}

$manifest = Read-BaknretManifest -Path $manifestPath

if (-not (Test-Path -LiteralPath $BackupListPath)) {
    Write-Log '未找到配置文件，正在从备份内容生成...' -Level INFO

    $paths = @()

    if ($manifest.items.Count -gt 0) {
        foreach ($key in $manifest.items.Keys) {
            $record = $manifest.items[$key]
            if ($record.PSObject.Properties.Name -contains 'source' -and $record.source) {
                $paths += $record.source
            }
        }
    }

    if ($paths.Count -eq 0) {
        $backupFiles = Get-ChildItem -LiteralPath $BackupDir -File -Force -ErrorAction SilentlyContinue |
            Where-Object { $_.Extension.ToLower() -in $SupportedFormats -and $_.BaseName -match '_from_' }
        foreach ($file in $backupFiles) {
            $original = Convert-BackupFileNameToPath -FileName $file.Name
            if ($original) { $paths += $original }
        }
    }

    $paths = @($paths | Sort-Object -Unique)
    if ($paths.Count -eq 0) {
        Write-Log '无法从备份内容还原出任何路径。' -Level ERROR
        Stop-BaknretLog
        exit 1
    }

    $content = "# BackupList.txt（自动生成，排除规则需要手工补回）`n" + (($paths -join [Environment]::NewLine) + [Environment]::NewLine)
    [System.IO.File]::WriteAllText($BackupListPath, $content, [System.Text.UTF8Encoding]::new($false))
    Write-Log "已生成配置，包含 $($paths.Count) 个项目，请检查后重新运行" -Level INFO
    Stop-BaknretLog
    exit 0
}

function Test-EntrySelected {
    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
}

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

$lines = Get-Content -LiteralPath $BackupListPath -ErrorAction Stop
$stats = @{ restored = 0; skipped = 0; failed = 0; verified = 0; planned = 0 }
$failures = @()
$referencedArchives = @()

# 只有真的恢复成功了才允许写回 manifest。
# -WhatIf / -DryRun / -VerifyOnly 以及"全部跳过"的运行必须一个字节都不写：
# 之前这里无条件写回，实际上只是把 updatedAt 改了，却直接违背了
# "试运行不会写入任何文件" 的承诺（已用 manifest 的 SHA256 复现）。
$manifestDirty = $false

Write-Log '开始执行恢复' -Level INFO

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
    $baseName = $resolved.BaseName

    if (-not $baseName) { $stats.skipped++; continue }
    if (-not (Test-EntrySelected -DisplayPath $displayPath -BaseName $baseName)) { continue }

    $found = Get-ArchiveForEntry -Entry ([pscustomobject]@{ baseName = $baseName }) -Manifest $manifest
    if (-not $found) {
        Write-Log "跳过: $displayPath，未找到归档 $baseName" -Level WARN
        $stats.skipped++
        continue
    }

    # 恢复目的地。一个条目可能带多个源（软件名录里的数组写法、`:+` 追加、
    # 或同名目录分散在多处），每个源只还原**它自己那棵子树**。
    $targets = @()
    if ($resolved.Sources.Count -gt 0) {
        foreach ($source in $resolved.Sources) {
            $targets += [pscustomobject]@{
                DestPath     = $source.SourcePath
                RelativePath = @($source.RelativePaths)[0]
                Description  = $source.Description
                Origin       = $source.Origin
            }
        }
    } else {
        $expanded = [Environment]::ExpandEnvironmentVariables($displayPath)
        $targets += [pscustomobject]@{
            DestPath     = $expanded
            RelativePath = (Split-Path -Path $expanded -Leaf)
            Description  = $null
            Origin       = 'path'
        }
    }

    # 防御：解析不出目的地时明确失败，别把空字符串喂给 Split-Path/Test-Path
    # （那种报错是 "Cannot bind argument to parameter 'Path' because it is an empty string"）
    $targets = @($targets | Where-Object { $_.DestPath -and -not [string]::IsNullOrWhiteSpace($_.DestPath) })
    if ($targets.Count -eq 0) {
        $reason = "无法确定恢复目的地（清单条目 '$displayPath' 解析不出任何源路径）"
        Write-Log "失败: $displayPath，$reason" -Level ERROR
        $stats.failed++
        $failures += $displayPath
        continue
    }

    $destPath = $targets[0].DestPath

    $archiveFile = $found.File
    $referencedArchives += $archiveFile.BaseName

    # 加密归档在取不到口令时必须直接失败：7z 在没有 -p 时会在控制台等输入，
    # 在计划任务里会静默挂起，比报错更糟。
    $isEncrypted = $false
    if ($found.Record -and ($found.Record.PSObject.Properties.Name -contains 'encrypted')) {
        $isEncrypted = [bool]$found.Record.encrypted
    }
    if ($isEncrypted -and -not $password) {
        Write-Log "失败: $displayPath，归档已加密但取不到口令（设置 BAKNRET_PASSWORD 或用 -KeyFile 指定密码文件）" -Level ERROR
        $stats.failed++
        $failures += $displayPath
        continue
    }

    if ($VerifyOnly) {
        if ($archiveFile.Extension.ToLower() -ne '.7z') {
            Write-Log "跳过校验（非 7z）: $($archiveFile.Name)" -Level DEBUG
            continue
        }
        $verifyTool = Get-7zExecutable
        if (-not $verifyTool) {
            Write-Log '未找到 7z，无法校验' -Level ERROR
            $stats.failed++
            $failures += $displayPath
            continue
        }
        $verifyArgument = @('t', '-bso0', '-bsp0')
        if ($password) { $verifyArgument += "-p$password" }
        $verifyArgument += $archiveFile.FullName
        $verifyCode = Invoke-ExternalCommand -FilePath $verifyTool -ArgumentList $verifyArgument
        if ($verifyCode -eq 0) {
            Write-Log "校验通过: $($archiveFile.Name)" -Level INFO
            $stats.verified++
        } else {
            Write-Log "校验失败: $($archiveFile.Name)（退出码 $verifyCode）" -Level ERROR
            $stats.failed++
            $failures += $displayPath
        }
        continue
    }

    Write-Log "准备恢复: $displayPath  <-  $($archiveFile.Name)（来源：$($found.Source)）" -Level INFO

    if ((Test-Path -LiteralPath $destPath) -and -not $Force) {
        try {
            $destSummary = Get-FolderSummary -FolderPath $destPath
            $archiveTime = $archiveFile.LastWriteTime
            if ($destSummary.LatestModifiedTime -and $destSummary.LatestModifiedTime -gt $archiveTime) {
                Write-Log "跳过: $displayPath，目标目录比归档新（用 -Force 覆盖）" -Level WARN
                $stats.skipped++
                continue
            }
        } catch {
            Write-Log "目标目录摘要读取失败，继续恢复：$_" -Level DEBUG
        }
    }

    $plannedTargets = @($targets | Where-Object { $_.DestPath })

    # 说清楚"这条会把哪些目录还原到哪儿、为什么"
    Write-Log ("恢复计划：{0}（归档 {1}）" -f $displayPath, $archiveFile.Name)
    foreach ($target in $plannedTargets) {
        $targetExists = Test-Path -LiteralPath $target.DestPath
        Write-Log ("  目标：{0}" -f $target.DestPath)
        Write-Log ("      归档内子树：{0}；{1}" -f $target.RelativePath, $(if ($targetExists) { '已存在，将覆盖同名文件' } else { '不存在，将新建' }))
        if ($target.Description) { Write-Log ("      介绍：{0}" -f $target.Description) }
    }

    foreach ($target in $plannedTargets) {
        if (Test-Path -LiteralPath $target.DestPath) { continue }
        # Split-Path -Parent 对根路径（如 "E:\"）返回空串，此时无父目录可建
        $targetParent = Split-Path -Path $target.DestPath -Parent
        if ($targetParent) {
            Write-Log "提示: 目标不存在，将新建 $targetParent" -Level DEBUG
        } else {
            Write-Log "提示: 目标不存在，且没有可创建的父目录：$($target.DestPath)" -Level DEBUG
        }
    }

    $shouldRun = $true
    foreach ($target in $plannedTargets) {
        if (-not $PSCmdlet.ShouldProcess($target.DestPath, "从 $($archiveFile.Name) 解压")) { $shouldRun = $false }
    }

    if (-not $shouldRun) {
        foreach ($target in $plannedTargets) {
            Write-Log "[试运行] 将解压 $($archiveFile.Name) -> $($target.DestPath)" -Level INFO
        }
        $stats.planned++
        continue
    }

    $restoreFailed = $false
    try {
        foreach ($target in $plannedTargets) {
            if (-not (Invoke-Extraction -ArchiveFile $archiveFile -DestinationPath $target.DestPath -RelativePath $target.RelativePath)) {
                $restoreFailed = $true
                break
            }
        }

        if (-not $restoreFailed) {
            $stats.restored++
            Write-Log "恢复成功: $baseName" -Level INFO

            if ($manifest.items.Contains($baseName)) {
                $record = $manifest.items[$baseName]
                if ($record -is [System.Collections.IDictionary]) {
                    $record['lastRestoreAt'] = (Get-Date).ToString('o')
                } else {
                    $record | Add-Member -NotePropertyName lastRestoreAt -NotePropertyValue ((Get-Date).ToString('o')) -Force
                }
                $manifestDirty = $true
            }
        } else {
            $stats.failed++
            $failures += $displayPath
        }
    } catch {
        Write-Log "恢复失败: $displayPath，$_" -Level ERROR
        $stats.failed++
        $failures += $displayPath
    }
}

# ============================================================================
# 收尾：报告孤儿归档
# ============================================================================

if (-not $VerifyOnly -and $Only.Count -eq 0 -and $Skip.Count -eq 0) {
    $orphans = @(Get-ChildItem -LiteralPath $BackupDir -File -Force -ErrorAction SilentlyContinue |
        Where-Object { $_.Extension.ToLower() -in $SupportedFormats -and $_.BaseName -notin $referencedArchives })

    if ($orphans.Count -gt 0) {
        Write-Log '以下归档没有任何清单条目指向（恢复不到，注意别误删）：' -Level WARN
        foreach ($orphan in $orphans) {
            Write-Log ("  - {0}（{1} MB，{2}）" -f $orphan.Name, [math]::Round($orphan.Length / 1MB, 2), $orphan.LastWriteTime) -Level WARN
        }
    }
} elseif (-not $VerifyOnly) {
    # 带 -Only/-Skip 时只有被选中的条目会被处理，其余归档都不在 $referencedArchives 里，
    # 按上面的算法报出来全是假孤儿（还会吓唬人说"注意别误删"），所以整段跳过。
    Write-Log '本次只恢复了部分条目，跳过孤儿归档审计（避免把未选中的归档误报成孤儿）' -Level DEBUG
}

try {
    if ($manifestDirty) {
        Write-BaknretManifest -Path $manifestPath -Manifest $manifest | Out-Null
        Write-Log 'manifest 已更新（记下本次恢复时间）' -Level DEBUG
    } else {
        Write-Log 'manifest 无需更新：本次没有实际恢复任何条目' -Level DEBUG
    }
} catch {
    Write-Log "manifest 写回失败（不影响本次恢复）：$_" -Level WARN
}

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

$summaryText = "恢复完成 - 成功：$($stats.restored)，跳过：$($stats.skipped)，失败：$($stats.failed)"
if ($VerifyOnly) { $summaryText = "校验完成 - 通过：$($stats.verified)，失败：$($stats.failed)" }
if ($stats.planned -gt 0) { $summaryText += "，试运行计划：$($stats.planned)" }
Write-Log $summaryText -Level INFO

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

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