backup_module.ps1

<#
 BackupModule.ps1 - 系統備份模組
支援 EFI、MSR、Windows 分割區備份
Version: v0.2
#>
function Start-SystemBackup {
    param(
        [int]$DiskIndex,
        [string]$BackupPath,
        [scriptblock]$ProgressCallback,
        [scriptblock]$LogCallback
    )

    $result = @{
        Success = $false
        BackupFile = $null
        Error = $null
    }

    try {
        # 呼叫日誌回調
        if ($LogCallback) { & $LogCallback "開始分析磁碟 $DiskIndex..." }

        # 獲取磁碟資訊
        $disk = Get-Disk -Number $DiskIndex
        if (-not $disk) {
            throw "無法找到磁碟 $DiskIndex"
        }

        # 獲取分割區資訊
        $partitions = Get-Partition -DiskNumber $DiskIndex | Sort-Object PartitionNumber
        if ($LogCallback) { & $LogCallback "發現 $($partitions.Count) 個分割區" }

        # 建立備份檔案名稱
        $timestamp = Get-Date -Format "yyyyMMdd_HHmmss"
        $backupFileName = "SystemBackup_Disk$($DiskIndex)_$timestamp.wim"
        $backupFilePath = Join-Path $BackupPath $backupFileName

        # 確保備份目錄存在
        if (-not (Test-Path $BackupPath)) {
            New-Item -Path $BackupPath -ItemType Directory -Force | Out-Null
            if ($LogCallback) { & $LogCallback "建立備份目錄: $BackupPath" }
        }

        # 檢查可用空間
        $driveInfo = Get-WmiObject -Class Win32_LogicalDisk | Where-Object { $_.DeviceID -eq ([System.IO.Path]::GetPathRoot($BackupPath)).TrimEnd('\') }
        $availableSpaceGB = [math]::Round($driveInfo.FreeSpace / 1GB, 2)
        $diskSizeGB = [math]::Round($disk.Size / 1GB, 2)
        
        if ($LogCallback) { & $LogCallback "目標磁碟可用空間: $availableSpaceGB GB，來源磁碟大小: $diskSizeGB GB" }

        if ($availableSpaceGB -lt ($diskSizeGB * 0.5)) {
            if ($LogCallback) { & $LogCallback "警告: 可用空間可能不足，建議至少保留 50% 的來源磁碟空間" }
        }

        # 開始備份程序
        if ($ProgressCallback) { & $ProgressCallback 10 }

        # 分析每個分割區類型
        $systemPartitions = @()
        $dataPartitions = @()

        foreach ($partition in $partitions) {
            $partitionType = $partition.Type
            $partitionSize = [math]::Round($partition.Size / 1MB, 2)
            
            if ($LogCallback) { & $LogCallback "分割區 $($partition.PartitionNumber): $partitionType ($partitionSize MB)" }

            switch ($partitionType) {
                "System" { 
                    $systemPartitions += $partition
                    if ($LogCallback) { & $LogCallback "  -> EFI 系統分割區" }
                }
                "Reserved" { 
                    $systemPartitions += $partition
                    if ($LogCallback) { & $LogCallback "  -> MSR 保留分割區" }
                }
                "Basic" { 
                    if ($partition.DriveLetter) {
                        $dataPartitions += $partition
                        if ($LogCallback) { & $LogCallback "  -> 資料分割區 ($($partition.DriveLetter):)" }
                    } else {
                        $systemPartitions += $partition
                        if ($LogCallback) { & $LogCallback "  -> 系統分割區 (無磁碟機代號)" }
                    }
                }
                default {
                    $systemPartitions += $partition
                    if ($LogCallback) { & $LogCallback "  -> 其他系統分割區" }
                }
            }
        }

        if ($ProgressCallback) { & $ProgressCallback 20 }

        # 使用 DISM 建立 WIM 映像檔
        $config = Get-AppConfig
        $dismPath = $config.DismPath

        if (-not (Test-Path $dismPath)) {
            throw "找不到 DISM 執行檔: $dismPath"
        }

        # 建立完整磁碟映像
        if ($LogCallback) { & $LogCallback "開始建立磁碟映像..." }
        
        # 使用 DISM 的 capture-image 功能
        $windowsPartition = $dataPartitions | Where-Object { $_.DriveLetter -and (Test-Path "$($_.DriveLetter):\Windows") } | Select-Object -First 1
        
        if ($windowsPartition) {
            $sourceDrive = "$($windowsPartition.DriveLetter):"
            if ($LogCallback) { & $LogCallback "發現 Windows 分割區: $sourceDrive" }
            
            # 建立 Windows 映像
            $dismArgs = @(
                "/Capture-Image"
                "/ImageFile:`"$backupFilePath`""
                "/CaptureDir:$sourceDrive"
                "/Name:`"SystemBackup_$timestamp`""
                "/Description:`"Full System Backup created on $(Get-Date)`""
                "/Compress:max"
                "/CheckIntegrity"
            )

            if ($ProgressCallback) { & $ProgressCallback 30 }

            $dismProcess = Start-Process -FilePath $dismPath -ArgumentList $dismArgs -Wait -PassThru -NoNewWindow -RedirectStandardOutput "$env:TEMP\dism_output.log" -RedirectStandardError "$env:TEMP\dism_error.log"

            if ($dismProcess.ExitCode -ne 0) {
                $errorLog = Get-Content "$env:TEMP\dism_error.log" -Raw
                Add-LogEntry -Message "DISM 執行失敗 (錯誤碼: $($dismProcess.ExitCode))" -Level ERROR
                Add-LogEntry -Message "DISM 錯誤輸出: $errorLog" -Level DEBUG
                throw "DISM 執行失敗 (錯誤碼: $($dismProcess.ExitCode))"
            }

            if ($ProgressCallback) { & $ProgressCallback 70 }
            if ($LogCallback) { & $LogCallback "Windows 分割區映像建立完成" }
        } else {
            throw "無法找到 Windows 分割區"
        }

        # 備份分割區表和 MBR/GPT 資訊
        $partitionInfoFile = Join-Path $BackupPath "PartitionInfo_Disk$($DiskIndex)_$timestamp.json"
        $diskInfo = @{
            DiskNumber = $DiskIndex
            PartitionStyle = $disk.PartitionStyle
            Size = $disk.Size
            Partitions = @()
            Timestamp = Get-Date
        }

        foreach ($partition in $partitions) {
            $partInfo = @{
                PartitionNumber = $partition.PartitionNumber
                Type = $partition.Type
                Size = $partition.Size
                Offset = $partition.Offset
                DriveLetter = $partition.DriveLetter
                IsActive = $partition.IsActive
                IsBoot = $partition.IsBoot
                IsSystem = $partition.IsSystem
            }
            $diskInfo.Partitions += $partInfo
        }

        $diskInfo | ConvertTo-Json -Depth 10 | Out-File -FilePath $partitionInfoFile -Encoding UTF8
        if ($LogCallback) { & $LogCallback "分割區資訊已儲存: $partitionInfoFile" }

        if ($ProgressCallback) { & $ProgressCallback 85 }

        # 備份開機記錄 (僅適用於系統磁碟)
        if ($disk.IsBoot -or $disk.IsSystem) {
            $bootBackupFile = Join-Path $BackupPath "BootSector_Disk$($DiskIndex)_$timestamp.bin"
            
            try {
                # 使用 dd 類似的功能備份 MBR/GPT
                $bootSectorBackup = Export-BootSector -DiskNumber $DiskIndex -OutputFile $bootBackupFile
                if ($LogCallback) { & $LogCallback "開機磁區已備份: $bootBackupFile" }
            }
            catch {
                if ($LogCallback) { & $LogCallback "警告: 無法備份開機磁區: $($_.Exception.Message)" }
            }
        }

        if ($ProgressCallback) { & $ProgressCallback 95 }

        # 驗證備份檔案
        if (Test-Path $backupFilePath) {
            $backupFileSize = (Get-Item $backupFilePath).Length
            $backupFileSizeGB = [math]::Round($backupFileSize / 1GB, 2)
            if ($LogCallback) { & $LogCallback "備份檔案大小: $backupFileSizeGB GB" }
            
            # 使用 DISM 驗證映像完整性
            $verifyArgs = @(
                "/Get-ImageInfo"
                "/ImageFile:`"$backupFilePath`""
            )
            
            $verifyProcess = Start-Process -FilePath $dismPath -ArgumentList $verifyArgs -Wait -PassThru -NoNewWindow -RedirectStandardOutput "$env:TEMP\dism_verify.log" -RedirectStandardError "$env:TEMP\dism_verify_error.log"
            
            if ($verifyProcess.ExitCode -eq 0) {
                if ($LogCallback) { & $LogCallback "映像檔完整性驗證通過" }
                $result.Success = $true
                $result.BackupFile = $backupFilePath
            } else {
                throw "映像檔完整性驗證失敗"
            }
        } else {
            throw "備份檔案建立失敗"
        }

        if ($ProgressCallback) { & $ProgressCallback 100 }
        if ($LogCallback) { & $LogCallback "系統備份完成！" }

    }
    catch {
        $result.Error = $_.Exception.Message
        if ($LogCallback) { & $LogCallback "備份失敗: $($_.Exception.Message)" }
    }

    return $result
}

function Export-BootSector {
    param(
        [int]$DiskNumber,
        [string]$OutputFile
    )

    # 開啟磁碟進行讀取
    $diskPath = "\\.\PhysicalDrive$DiskNumber"
    
    try {
        # 使用 .NET FileStream 讀取前 1MB 的資料 (包含 MBR/GPT)
        $fileStream = [System.IO.FileStream]::new($diskPath, [System.IO.FileMode]::Open, [System.IO.FileAccess]::Read, [System.IO.FileShare]::ReadWrite)
        $buffer = New-Object byte[] (1024 * 1024)  # 1MB buffer
        $bytesRead = $fileStream.Read($buffer, 0, $buffer.Length)
        $fileStream.Close()

        # 寫入備份檔案
        [System.IO.File]::WriteAllBytes($OutputFile, $buffer)
        
        return @{ Success = $true; BytesRead = $bytesRead }
    }
    catch {
        throw "無法讀取磁碟開機磁區: $($_.Exception.Message)"
    }
}

function Get-WindowsPartition {
    param([int]$DiskNumber)
    
    $partitions = Get-Partition -DiskNumber $DiskNumber
    foreach ($partition in $partitions) {
        if ($partition.DriveLetter -and (Test-Path "$($partition.DriveLetter):\Windows")) {
            return $partition
        }
    }
    return $null
}

function Test-AdminRights {
    return ([Security.Principal.WindowsPrincipal] [Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] "Administrator")
}

# 匯出函數
Export-ModuleMember -Function Start-SystemBackup, Export-BootSector, Get-WindowsPartition, Test-AdminRights