Add registry backup & restore (#566)

Starting from this commit, Win11Debloat will automatically create a registry backup every time the script is run. This registry backup can be used to revert any registry changes made by the script.

Scripts/Features/BackupRegistryState.ps1

@@ -0,0 +1,88 @@
+function New-RegistrySettingsBackup {
+    param(
+        [string[]]$ActionableKeys
+    )
+
+    $ActionableKeys = @($ActionableKeys)
+    $selectedFeatures = Get-SelectedFeatures -ActionableKeys $ActionableKeys
+    if (@($selectedFeatures | Where-Object { -not [string]::IsNullOrWhiteSpace([string]$_.RegistryKey) }).Count -eq 0) {
+        return $null
+    }
+
+    $timestamp = Get-Date
+    $backupDirectory = $script:RegistryBackupsPath
+    if (-not (Test-Path $backupDirectory)) {
+        New-Item -ItemType Directory -Path $backupDirectory -Force | Out-Null
+    }
+
+    $backupFileName = 'Win11Debloat-RegistryBackup-{0}.json' -f $timestamp.ToString('yyyyMMdd_HHmmss')
+    $backupFilePath = Join-Path $backupDirectory $backupFileName
+
+    $backupConfig = Get-RegistryBackupPayload -SelectedFeatures $selectedFeatures -CreatedAt $timestamp
+    if (-not (SaveToFile -Config $backupConfig -FilePath $backupFilePath -MaxDepth 25)) {
+        throw "Failed to save registry backup to '$backupFilePath'"
+    }
+
+    Write-Host "Backup successfully created: $backupFilePath"
+    Write-Host ""
+
+    return $backupFilePath
+}
+
+function Get-SelectedFeatures {
+    param(
+        [string[]]$ActionableKeys
+    )
+
+    $selectedFeatures = New-Object System.Collections.Generic.List[object]
+    $selectedFeatureIds = New-Object 'System.Collections.Generic.HashSet[string]' ([System.StringComparer]::OrdinalIgnoreCase)
+
+    foreach ($paramKey in $ActionableKeys) {
+        if (-not $script:Features.ContainsKey($paramKey)) { continue }
+
+        $feature = $script:Features[$paramKey]
+        if (-not $feature) { continue }
+
+        $featureId = Get-FeatureId -Feature $feature
+
+        if ($selectedFeatureIds.Add($featureId)) {
+            $selectedFeatures.Add($feature)
+        }
+    }
+
+    return @($selectedFeatures.ToArray())
+}
+
+function Get-RegistryBackupPayload {
+    param(
+        [Parameter(Mandatory)]
+        [object[]]$SelectedFeatures,
+        [Parameter(Mandatory)]
+        [datetime]$CreatedAt
+    )
+
+    $selectedFeatureIds = New-Object System.Collections.Generic.List[string]
+    $seenSelectedFeatureIds = New-Object 'System.Collections.Generic.HashSet[string]' ([System.StringComparer]::OrdinalIgnoreCase)
+    foreach ($feature in $SelectedFeatures) {
+        $featureId = Get-FeatureId -Feature $feature
+
+        if ($seenSelectedFeatureIds.Add($featureId)) {
+            $selectedFeatureIds.Add($featureId)
+        }
+    }
+
+    $selectedRegistryFeatures = Get-RegistryBackedFeatures -Features $SelectedFeatures
+    $capturePlans = Get-RegistryBackupCapturePlans -SelectedRegistryFeatures $SelectedRegistryFeatures
+    $registryKeys = @(Get-RegistrySnapshotsForBackup -CapturePlans $capturePlans)
+
+    return @{
+        Version = '1.0'
+        BackupType = 'RegistryState'
+        CreatedAt = $CreatedAt.ToString('o')
+        CreatedBy = 'Win11Debloat'
+        Target = (Get-RegistryBackupTargetDescription)
+        ComputerName = $env:COMPUTERNAME
+        SelectedFeatures = @($selectedFeatureIds)
+        RegistryKeys = @($registryKeys)
+    }
+}