# DeployCenter - Discover and generate Windows answer-file profiles.
# PSD1 profiles remain data files; answer files are built as XML.

function Get-DeployCenterUnattendProfileNames {
    [CmdletBinding()]
    param([Parameter(Mandatory=$true)][string]$ProfilesRoot)

    if (-not (Test-Path -LiteralPath $ProfilesRoot -PathType Container)) { return @() }
    $names = @()
    foreach ($file in (Get-ChildItem -LiteralPath $ProfilesRoot -Filter '*.psd1' -File -ErrorAction SilentlyContinue)) {
        if ($file.BaseName -match '^[A-Za-z0-9_-]+$') { $names += $file.BaseName }
    }
    return @($names | Sort-Object -Unique)
}

function Import-DeployCenterUnattendProfile {
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)][string]$ProfilesRoot,
        [Parameter(Mandatory=$true)][string]$ProfileName
    )

    if ($ProfileName -notmatch '^[A-Za-z0-9_-]+$') { throw "Invalid Unattend profile name: $ProfileName" }
    $path = Join-Path $ProfilesRoot ($ProfileName + '.psd1')
    if (-not (Test-Path -LiteralPath $path -PathType Leaf)) { throw "Unattend profile not found: $ProfileName" }
    $profile = Import-PowerShellDataFile -LiteralPath $path
    foreach ($key in @('Id','Name','Description','Target','Template','ComputerName','LocalAccount')) {
        if (-not $profile.ContainsKey($key)) { throw ('Unattend profile {0} does not contain key {1}.' -f $ProfileName, $key) }
    }
    if ([string]$profile.Id -ne $ProfileName) { throw ('Unattend profile ID {0} does not match the file name.' -f $ProfileName) }
    if ([string]$profile.Target -notin @('Workstation', 'Server')) { throw ('The Target property of Unattend profile {0} must be Workstation or Server.' -f $ProfileName) }
    if ([string]$profile.Template -notmatch '^[A-Za-z0-9_-]+\.xml$') { throw ('Invalid XML template name in profile {0}.' -f $ProfileName) }
    $templatesRoot = Join-Path (Split-Path -Parent $ProfilesRoot) 'Templates'
    $templatePath = Join-Path $templatesRoot ([string]$profile.Template)
    if (-not (Test-Path -LiteralPath $templatePath -PathType Leaf)) { throw "XML template not found for profile '$ProfileName': $templatePath" }
    if (-not [string]$profile.Name -or [string]::IsNullOrWhiteSpace([string]$profile.Name)) { throw ('Unattend profile {0} must define a display name.' -f $ProfileName) }
    $profile.TemplatePath = $templatePath
    return $profile
}

function Test-DeployCenterUnattendConfiguration {
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)][System.Collections.IDictionary]$Profile,
        [Parameter(Mandatory=$true)][System.Collections.IDictionary]$Configuration,
        [Parameter(Mandatory=$true)][string]$HostName
    )

    if ($Profile.ComputerName -and $HostName -notmatch '^(?=.*[A-Za-z])[A-Za-z0-9](?:[A-Za-z0-9-]{0,13}[A-Za-z0-9])?$') {
        throw 'The computer name must follow NetBIOS rules and not exceed 15 characters.'
    }
    if ($Profile.LocalAccount) {
        $accountName = [string]$Configuration.UnattendAdminName
        $displayName = [string]$Configuration.UnattendAdminDisplayName
        $groupName = [string]$Configuration.UnattendAdminGroup
        $passwordBase64 = [string]$Configuration.UnattendAdminPasswordBase64
        if ($accountName -notmatch '^[^"/\[\]:;|=,+*?<>\\]{1,20}$') { throw '[Unattend] AdminName must be 1 to 20 characters and must not contain characters prohibited by Windows.' }
        if ([string]::IsNullOrWhiteSpace($displayName)) { throw '[Unattend] AdminDisplayName cannot be empty.' }
        if ([string]::IsNullOrWhiteSpace($groupName)) { throw '[Unattend] AdminGroup cannot be empty.' }
        if ([string]::IsNullOrWhiteSpace($passwordBase64)) { throw 'The [Unattend] AdminPasswordBase64 setting is required for this profile.' }
        try {
            $passwordBytes = [Convert]::FromBase64String($passwordBase64)
            if ($passwordBytes.Length -eq 0 -or ($passwordBytes.Length % 2) -ne 0 -or
                [string]::IsNullOrEmpty([Text.Encoding]::Unicode.GetString($passwordBytes))) {
                throw 'Invalid UTF-16LE Base64 format.'
            }
        } catch {
            throw '[Unattend] AdminPasswordBase64 must be a UTF-16LE password encoded as Base64.'
        }
    }
}

function New-DeployCenterUnattendXml {
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)][System.Collections.IDictionary]$Profile,
        [Parameter(Mandatory=$true)][System.Collections.IDictionary]$Configuration,
        [Parameter(Mandatory=$true)][string]$HostName,
        [Parameter(Mandatory=$true)][string]$Architecture,
        [AllowEmptyString()][string]$WallpaperPath = ''
    )

    Test-DeployCenterUnattendConfiguration -Profile $Profile -Configuration $Configuration -HostName $HostName
    $document = New-Object System.Xml.XmlDocument
    $document.PreserveWhitespace = $true
    $document.Load([string]$Profile.TemplatePath)
    $namespaces = New-Object System.Xml.XmlNamespaceManager($document.NameTable)
    $namespaces.AddNamespace('u', 'urn:schemas-microsoft-com:unattend')
    $namespaces.AddNamespace('wcm', 'http://schemas.microsoft.com/WMIConfig/2002/State')

    $processorArchitecture = switch -Regex ($Architecture.ToLowerInvariant()) {
        'arm64' { 'arm64'; break }
        'x86|32' { 'x86'; break }
        default { 'amd64' }
    }
    foreach ($component in $document.SelectNodes('//u:component', $namespaces)) {
        $component.SetAttribute('processorArchitecture', $processorArchitecture)
    }
    if ($Profile.ComputerName) {
        $node = $document.SelectSingleNode('/u:unattend/u:settings[@pass="specialize"]/u:component[@name="Microsoft-Windows-Shell-Setup"]/u:ComputerName', $namespaces)
        if ($null -eq $node) { throw ('The template for profile {0} does not define the ComputerName node in specialize.' -f $Profile.Id) }
        $node.InnerText = $HostName
    }
    if ($Profile.LocalAccount) {
        $values = @{
            Name = [string]$Configuration.UnattendAdminName
            DisplayName = [string]$Configuration.UnattendAdminDisplayName
            Group = [string]$Configuration.UnattendAdminGroup
            Password = [string]$Configuration.UnattendAdminPasswordBase64
        }
        foreach ($name in $values.Keys) {
            $field = if ($name -eq 'Password') { 'Password/u:Value' } else { $name }
            $node = $document.SelectSingleNode("/u:unattend/u:settings[@pass='oobeSystem']/u:component[@name='Microsoft-Windows-Shell-Setup']/u:UserAccounts/u:LocalAccounts/u:LocalAccount/u:$field", $namespaces)
            if ($null -eq $node) { throw ('The template for profile {0} does not define the account field {1}.' -f $Profile.Id, $name) }
            $node.InnerText = $values[$name]
        }
    }
    $supportAppUrl = [string]$Configuration.UnattendSupportAppURL
    $supportUrl = [string]$Configuration.UnattendSupportURL
    # Compatibility: before SupportURL was added, a web URL could be provided in SupportAppURL.
    if ($supportAppUrl -match '^https?://') {
        if ([string]::IsNullOrWhiteSpace($supportUrl)) { $supportUrl = $supportAppUrl }
        $supportAppUrl = ''
    }
    $supportSettings = @(
        @{ Name = 'SupportProvider'; Value = [string]$Configuration.UnattendSupportProvider },
        @{ Name = 'SupportURL'; Value = $supportUrl },
        @{ Name = 'SupportAppURL'; Value = $supportAppUrl }
    )
    $oemInformationPath = '/u:unattend/u:settings[@pass="oobeSystem"]/u:component[@name="Microsoft-Windows-Shell-Setup"]/u:OEMInformation'
    foreach ($supportSetting in $supportSettings) {
        $supportNode = $document.SelectSingleNode(($oemInformationPath + '/u:' + $supportSetting.Name), $namespaces)
        if ($null -eq $supportNode) {
            if (-not [string]::IsNullOrWhiteSpace($supportSetting.Value)) {
                throw ('The template for profile {0} does not define the {1} node.' -f $Profile.Id, $supportSetting.Name)
            }
            continue
        }
        if ([string]::IsNullOrWhiteSpace($supportSetting.Value)) {
            [void]$supportNode.ParentNode.RemoveChild($supportNode)
        } else {
            $supportNode.InnerText = $supportSetting.Value
        }
    }
    $oemInformationNode = $document.SelectSingleNode($oemInformationPath, $namespaces)
    if ($null -ne $oemInformationNode -and $oemInformationNode.SelectNodes('u:*', $namespaces).Count -eq 0) {
        [void]$oemInformationNode.ParentNode.RemoveChild($oemInformationNode)
    }
    if (-not [string]::IsNullOrWhiteSpace($WallpaperPath)) {
        $shellSetupNode = $document.SelectSingleNode('/u:unattend/u:settings[@pass="oobeSystem"]/u:component[@name="Microsoft-Windows-Shell-Setup"]', $namespaces)
        if ($null -eq $shellSetupNode) { throw ('The template for profile {0} does not define the Shell-Setup component in oobeSystem.' -f $Profile.Id) }
        $themesNode = $shellSetupNode.SelectSingleNode('u:Themes', $namespaces)
        if ($null -eq $themesNode) {
            $themesNode = $document.CreateElement('Themes', 'urn:schemas-microsoft-com:unattend')
            [void]$shellSetupNode.AppendChild($themesNode)
        }
        foreach ($themeSetting in @(
            @{ Name = 'ThemeName'; Value = 'Blorand' },
            @{ Name = 'DesktopBackground'; Value = $WallpaperPath },
            @{ Name = 'UWPAppsUseLightTheme'; Value = 'true' }
        )) {
            $themeNode = $themesNode.SelectSingleNode(('u:' + $themeSetting.Name), $namespaces)
            if ($null -eq $themeNode) {
                $themeNode = $document.CreateElement($themeSetting.Name, 'urn:schemas-microsoft-com:unattend')
                [void]$themesNode.AppendChild($themeNode)
            }
            $themeNode.InnerText = [string]$themeSetting.Value
        }
    }
    return $document.OuterXml
}

Export-ModuleMember -Function Get-DeployCenterUnattendProfileNames, Import-DeployCenterUnattendProfile, Test-DeployCenterUnattendConfiguration, New-DeployCenterUnattendXml