#Requires -Version 5.1
[CmdletBinding(SupportsShouldProcess)]
param(
    [string]$DomainController = $env:COMPUTERNAME,
    [string]$StudentOuName = 'Alumnos',
    [string]$ProfessorOuName = 'Docentes',
    [string]$AdministrativeOuName = 'Administrativos',
    [string]$LaboratoryOuName = 'Laboratorio',
    [string]$StudentGroupName = 'SGU-Alumnos',
    [string]$ProfessorGroupName = 'SGU-Docentes',
    [string]$AdministrativeGroupName = 'SGU-Administrativos',
    [string]$StudentGpoName = 'SGU - AL redirected folders',
    [string]$StaffGpoName = 'SGU - AD-DO FSLogix profiles',
    [string]$FsLogixDeploymentGpoName = 'SGU - FSLogix client deployment',
    [switch]$PreserveLegacyUserMappings
)

$ErrorActionPreference = 'Stop'

function Assert-Administrator {
    $identity = [Security.Principal.WindowsIdentity]::GetCurrent()
    $principal = [Security.Principal.WindowsPrincipal]::new($identity)
    if (-not $principal.IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)) {
        throw 'Run this script from an elevated Windows PowerShell 5.1 session on the SGU domain controller.'
    }
}

function Set-SguPolicyValue {
    param(
        [Parameter(Mandatory)][string]$GpoName,
        [Parameter(Mandatory)][string]$DomainName,
        [Parameter(Mandatory)][string]$Server,
        [Parameter(Mandatory)][string]$Key,
        [Parameter(Mandatory)][string]$ValueName,
        [Parameter(Mandatory)][ValidateSet('DWord','String','ExpandString')][string]$Type,
        [Parameter(Mandatory)]$Value
    )
    if ($PSCmdlet.ShouldProcess("$GpoName :: $Key\\$ValueName", "Set rollback value $Value")) {
        Remove-GPRegistryValue -Name $GpoName -Domain $DomainName -Server $Server `
            -Key $Key -ValueName "**del.$ValueName" -ErrorAction SilentlyContinue | Out-Null
        Set-GPRegistryValue -Name $GpoName -Domain $DomainName -Server $Server `
            -Key $Key -ValueName $ValueName -Type $Type -Value $Value | Out-Null
    }
}

function Remove-SguPolicyValue {
    param(
        [Parameter(Mandatory)][string]$GpoName,
        [Parameter(Mandatory)][string]$DomainName,
        [Parameter(Mandatory)][string]$Server,
        [Parameter(Mandatory)][string]$Key,
        [Parameter(Mandatory)][string]$ValueName
    )
    if ($PSCmdlet.ShouldProcess("$GpoName :: $Key\\$ValueName", 'Remove roaming value')) {
        Remove-GPRegistryValue -Name $GpoName -Domain $DomainName -Server $Server `
            -Key $Key -ValueName $ValueName -ErrorAction SilentlyContinue | Out-Null
        Set-GPRegistryValue -Name $GpoName -Domain $DomainName -Server $Server `
            -Key $Key -ValueName "**del.$ValueName" -Type String -Value '' | Out-Null
    }
}

Assert-Administrator
Import-Module ActiveDirectory -ErrorAction Stop
Import-Module GroupPolicy -ErrorAction Stop

$domain = Get-ADDomain -Server $DomainController
$domainName = $domain.DNSRoot
$domainDn = $domain.DistinguishedName
$laboratoryOuDn = "OU=$LaboratoryOuName,$domainDn"
$usersOuDn = "OU=Usuarios-SGU,$domainDn"
$studentOuDn = "OU=$StudentOuName,$usersOuDn"
$professorOuDn = "OU=$ProfessorOuName,$usersOuDn"
$administrativeOuDn = "OU=$AdministrativeOuName,$usersOuDn"

foreach ($ou in $laboratoryOuDn,$studentOuDn,$professorOuDn,$administrativeOuDn) {
    Get-ADOrganizationalUnit -Identity $ou -Server $DomainController -ErrorAction Stop | Out-Null
}

$staffGpo = Get-GPO -Name $StaffGpoName -Domain $domainName -Server $DomainController `
    -ErrorAction SilentlyContinue
if (-not $staffGpo -and $PSCmdlet.ShouldProcess($StaffGpoName, 'Create local-profile enforcement GPO')) {
    $staffGpo = New-GPO -Name $StaffGpoName -Domain $domainName -Server $DomainController
}
if (-not $staffGpo) {
    throw "The GPO '$StaffGpoName' does not exist and was not created."
}
$staffLink = @(Get-GPInheritance -Target $laboratoryOuDn -Domain $domainName `
    -Server $DomainController).GpoLinks |
    Where-Object DisplayName -eq $StaffGpoName | Select-Object -First 1
if (-not $staffLink -and $PSCmdlet.ShouldProcess($laboratoryOuDn, "Link '$StaffGpoName'")) {
    New-GPLink -Name $StaffGpoName -Target $laboratoryOuDn -Domain $domainName `
        -Server $DomainController -LinkEnabled Yes | Out-Null
}
elseif ($staffLink -and -not [bool]$staffLink.Enabled -and
    $PSCmdlet.ShouldProcess($laboratoryOuDn, "Enable '$StaffGpoName' rollback link")) {
    Set-GPLink -Name $StaffGpoName -Target $laboratoryOuDn -Domain $domainName `
        -Server $DomainController -LinkEnabled Yes | Out-Null
}

$profilesRoot = 'HKLM\SOFTWARE\FSLogix\Profiles'
Set-SguPolicyValue -GpoName $StaffGpoName -DomainName $domainName -Server $DomainController `
    -Key $profilesRoot -ValueName Enabled -Type DWord -Value 0
Set-SguPolicyValue -GpoName $StaffGpoName -DomainName $domainName -Server $DomainController `
    -Key 'HKLM\SOFTWARE\FSLogix\ODFC' -ValueName Enabled -Type DWord -Value 0
foreach ($serviceName in 'frxsvc','frxccds') {
    Set-SguPolicyValue -GpoName $StaffGpoName -DomainName $domainName -Server $DomainController `
        -Key "HKLM\SYSTEM\CurrentControlSet\Services\$serviceName" `
        -ValueName Start -Type DWord -Value 4
}
Remove-SguPolicyValue -GpoName $StaffGpoName -DomainName $domainName -Server $DomainController `
    -Key 'HKLM\SOFTWARE\FSLogix\Apps' -ValueName VHDCompactDisk

$profileValueNames = @(
    'CCDLocations','VHDLocations','CcdUnregisterTimeout','ClearCacheOnForcedUnregister',
    'ClearCacheOnLogoff','HealthyProvidersRequiredForRegister',
    'HealthyProvidersRequiredForUnregister','PreventLoginWithFailure',
    'PreventLoginWithTempProfile','DeleteLocalProfileWhenVHDShouldApply',
    'FlipFlopProfileDirectoryName','IsDynamic','LockedRetryCount','LockedRetryInterval',
    'ProfileType','ReAttachIntervalSeconds','ReAttachRetryCount','SizeInMBs','VolumeType',
    'VHDCompactDisk'
)
$roleGroups = @(
    Get-ADGroup -Identity "CN=$ProfessorGroupName,$professorOuDn" -Server $DomainController
    Get-ADGroup -Identity "CN=$AdministrativeGroupName,$administrativeOuDn" -Server $DomainController
)
foreach ($group in $roleGroups) {
    $key = "$profilesRoot\ObjectSpecific\$($group.SID.Value)"
    Set-SguPolicyValue -GpoName $StaffGpoName -DomainName $domainName -Server $DomainController `
        -Key $key -ValueName Enabled -Type DWord -Value 0
    foreach ($valueName in $profileValueNames) {
        Remove-SguPolicyValue -GpoName $StaffGpoName -DomainName $domainName `
            -Server $DomainController -Key $key -ValueName $valueName
    }
}
Set-SguPolicyValue -GpoName $StaffGpoName -DomainName $domainName -Server $DomainController `
    -Key 'HKLM\SOFTWARE\SGU\UserRoaming' -ValueName StaffProfileStorageMode `
    -Type String -Value Disabled

$studentGpo = Get-GPO -Name $StudentGpoName -Domain $domainName -Server $DomainController `
    -ErrorAction SilentlyContinue
if ($studentGpo) {
    $studentLink = @(Get-GPInheritance -Target $studentOuDn -Domain $domainName `
        -Server $DomainController).GpoLinks |
        Where-Object DisplayName -eq $StudentGpoName | Select-Object -First 1
    if ($studentLink -and -not [bool]$studentLink.Enabled -and
        $PSCmdlet.ShouldProcess($studentOuDn, "Enable '$StudentGpoName' local-path rollback")) {
        Set-GPLink -Name $StudentGpoName -Target $studentOuDn -Domain $domainName `
            -Server $DomainController -LinkEnabled Yes | Out-Null
    }
    $shellFoldersKey = 'HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders'
    Set-SguPolicyValue -GpoName $StudentGpoName -DomainName $domainName -Server $DomainController `
        -Key $shellFoldersKey -ValueName Desktop -Type ExpandString `
        -Value '%USERPROFILE%\Desktop'
    Set-SguPolicyValue -GpoName $StudentGpoName -DomainName $domainName -Server $DomainController `
        -Key $shellFoldersKey -ValueName Personal -Type ExpandString `
        -Value '%USERPROFILE%\Documents'
    Remove-SguPolicyValue -GpoName $StudentGpoName -DomainName $domainName `
        -Server $DomainController -Key 'HKCU\Software\Policies\Microsoft\Windows\NetCache' `
        -ValueName DisableFRAdminPin
}

$deploymentGpo = Get-GPO -Name $FsLogixDeploymentGpoName -Domain $domainName `
    -Server $DomainController -ErrorAction SilentlyContinue
if ($deploymentGpo) {
    $deploymentLink = @(Get-GPInheritance -Target $laboratoryOuDn -Domain $domainName `
        -Server $DomainController).GpoLinks |
        Where-Object DisplayName -eq $FsLogixDeploymentGpoName | Select-Object -First 1
    if ($deploymentLink -and [bool]$deploymentLink.Enabled -and
        $PSCmdlet.ShouldProcess($laboratoryOuDn, "Disable '$FsLogixDeploymentGpoName'")) {
        Set-GPLink -Name $FsLogixDeploymentGpoName -Target $laboratoryOuDn `
            -Domain $domainName -Server $DomainController -LinkEnabled No | Out-Null
    }
}

$clearedUsers = [Collections.Generic.List[string]]::new()
if (-not $PreserveLegacyUserMappings) {
    foreach ($roleOu in $studentOuDn,$professorOuDn,$administrativeOuDn) {
        foreach ($user in Get-ADUser -SearchBase $roleOu -SearchScope Subtree -Filter * `
            -Server $DomainController -Properties profilePath,homeDirectory,homeDrive) {
            if ($user.profilePath -or $user.homeDirectory -or $user.homeDrive) {
                if ($PSCmdlet.ShouldProcess($user.SamAccountName, 'Clear AD profile and home-drive mappings')) {
                    Set-ADUser -Identity $user -Server $DomainController `
                        -Clear profilePath,homeDirectory,homeDrive
                    $clearedUsers.Add($user.SamAccountName)
                }
            }
        }
    }
}

$staffGpo = Get-GPO -Name $StaffGpoName -Domain $domainName -Server $DomainController
$studentGpo = Get-GPO -Name $StudentGpoName -Domain $domainName -Server $DomainController `
    -ErrorAction SilentlyContinue
$deploymentLink = @(Get-GPInheritance -Target $laboratoryOuDn -Domain $domainName `
    -Server $DomainController).GpoLinks |
    Where-Object DisplayName -eq $FsLogixDeploymentGpoName | Select-Object -First 1
[pscustomobject]@{
    Domain = $domainName
    UserRoamingEnabled = $false
    StaffGpoVersion = "$($staffGpo.Computer.DSVersion)/$($staffGpo.Computer.SysVolVersion)"
    StudentGpoVersion = if ($studentGpo) {
        "$($studentGpo.User.DSVersion)/$($studentGpo.User.SysVolVersion)"
    } else { $null }
    FsLogixDeploymentLinkEnabled = [bool]$deploymentLink.Enabled
    StaffProfilesEnabled = 0
    StudentDesktop = '%USERPROFILE%\Desktop'
    StudentDocuments = '%USERPROFILE%\Documents'
    ClearedAdUsers = @($clearedUsers)
    RebootManagedWindowsClients = $true
}