#requires -Version 5.1
<#
.SYNOPSIS
    Bulk device operations for Intune with enterprise-grade safeguards.
.DESCRIPTION
    Retire, wipe, delete, or sync devices in bulk with filtering, dry-run mode,
    and exclusions for hybrid-joined devices. Uses fzf when available.
.EXAMPLE
    ./Scripts/Bulk-DeviceOperations.ps1 -TenantId "contoso.onmicrosoft.com" -WhatIf
#>
[CmdletBinding()]
param(
    [Parameter(Mandatory = $true)]
    [string]$TenantId,

    [string]$AppId,

    [string]$Secret,

    [string]$Certificate,

    [ValidateSet("AppOnly","Browser","DeviceCode")]
    [string]$AuthMode = "AppOnly",

    [string]$RedirectUri,

    [string]$SettingsFile,

    [switch]$WhatIf
)

$ErrorActionPreference = "Stop"

#region Helper functions
function Test-FzfAvailable
{
    return [bool](Get-Command fzf -ErrorAction SilentlyContinue)
}

function Show-FzfMenu
{
    param(
        [Parameter(Mandatory)]
        [string[]]$Items,
        [string]$Header = "Select one",
        [switch]$Multi
    )
    $argsList = @("--header=$Header")
    if($Multi) { $argsList += "--multi" }
    $selected = $Items | fzf @argsList
    if(-not $selected) { return $null }
    if($Multi) { return @($selected -split "`r?`n" | Where-Object { $_ }) }
    return $selected
}

function Show-NumberedMenu
{
    param(
        [Parameter(Mandatory)]
        [string[]]$Items,
        [string]$Header = "Select one or more",
        [switch]$Multi
    )
    Write-Host "`n$Header" -ForegroundColor Cyan
    for($i=0; $i -lt $Items.Count; $i++)
    {
        Write-Host "  $($i+1). $($Items[$i])"
    }
    if($Multi)
    {
        $prompt = "Enter numbers separated by commas (e.g. 1,3,5) or 'all'"
    }
    else
    {
        $prompt = "Enter a number"
    }
    $choice = Read-Host $prompt
    if($choice -eq "all" -and $Multi) { return $Items }
    $indices = $choice -split "," | ForEach-Object { $_.Trim() } | Where-Object { $_ -match "^\d+$" } | ForEach-Object { [int]$_ - 1 } | Where-Object { $_ -ge 0 -and $_ -lt $Items.Count }
    if($Multi)
    {
        return $Items[$indices] | Select-Object -Unique
    }
    else
    {
        if($indices.Count -eq 0) { return $null }
        return $Items[$indices[0]]
    }
}

function Select-MenuItem
{
    param(
        [Parameter(Mandatory)]
        [string[]]$Items,
        [string]$Header = "Select one",
        [switch]$Multi
    )
    if(Test-FzfAvailable)
    {
        return Show-FzfMenu -Items $Items -Header $Header -Multi:$Multi
    }
    return Show-NumberedMenu -Items $Items -Header $Header -Multi:$Multi
}

function Read-YesNo
{
    param(
        [string]$Prompt,
        [bool]$Default = $false
    )
    $defaultChar = if($Default) { "Y" } else { "N" }
    $response = Read-Host "$Prompt [Y/n] (default: $defaultChar)"
    if([string]::IsNullOrWhiteSpace($response)) { return $Default }
    return $response -match "^\s*y"
}

function Get-DefaultSettingsPath
{
    if($IsWindows -or $env:OS -eq "Windows_NT")
    {
        if($env:LOCALAPPDATA) { return (Join-Path $env:LOCALAPPDATA "macOS_IntuneManagement\Settings.json") }
        return (Join-Path $env:USERPROFILE "AppData\Local\macOS_IntuneManagement\Settings.json")
    }
    if($IsMacOS) { return (Join-Path $HOME "Library/Application Support/macOS_IntuneManagement/Settings.json") }
    return (Join-Path $HOME ".local/share/macOS_IntuneManagement/Settings.json")
}
#endregion

#region Initialize Runtime
$projectRoot = Split-Path -Parent $PSScriptRoot
$runtimeModule = Join-Path $projectRoot "Runtime/IntuneManagement.Runtime.psd1"
if(-not (Test-Path $runtimeModule))
{
    throw "Could not find IntuneManagement.Runtime.psd1 in $projectRoot"
}

$settingsPath = $SettingsFile
if(-not $settingsPath)
{
    $settingsPath = Get-DefaultSettingsPath
}

# Pre-load auth from settings
if($AuthMode -eq "AppOnly" -and (Test-Path $settingsPath) -and (-not $AppId -or (-not $Secret -and -not $Certificate)))
{
    try
    {
        $raw = Get-Content -Path $settingsPath -Raw -ErrorAction Stop
        $settingsObj = ConvertFrom-Json $raw -AsHashtable -ErrorAction Stop
        if($settingsObj -and $settingsObj.ContainsKey($TenantId))
        {
            $tenantNode = $settingsObj[$TenantId]
            if(-not $AppId -and $tenantNode.ContainsKey("GraphAzureAppId"))
            {
                $AppId = $tenantNode["GraphAzureAppId"]
            }
            if(-not $Secret -and $tenantNode.ContainsKey("GraphAzureAppSecret"))
            {
                $Secret = $tenantNode["GraphAzureAppSecret"]
            }
            if(-not $Certificate -and $tenantNode.ContainsKey("GraphAzureAppCert"))
            {
                $Certificate = $tenantNode["GraphAzureAppCert"]
            }
        }

        if(-not $Secret -and $IsMacOS -and $AppId)
        {
            try
            {
                $keychainSecret = security find-generic-password -a "IntuneManagement" -s "IntuneMgmt-$AppId" -w 2>$null
                if($keychainSecret) { $Secret = $keychainSecret }
            }
            catch { }
        }
    }
    catch { }
}

$invokeParams = @{
    Silent = $true
    JSonSettings = $true
    JSonFile = $settingsPath
    TenantId = $TenantId
    AppId = $AppId
    AuthMode = $AuthMode
}
if($RedirectUri) { $invokeParams.RedirectUri = $RedirectUri }
if($AuthMode -eq "AppOnly" -and $Secret) { $invokeParams.Secret = $Secret }
elseif($AuthMode -eq "AppOnly") { $invokeParams.Certificate = $Certificate }

Import-Module $runtimeModule -Force
Initialize-IntuneManagementRuntime -View "IntuneGraphAPI" @invokeParams
#endregion

#region Ensure Graph connectivity
if(-not (Get-Command Invoke-GraphRequest -ErrorAction SilentlyContinue))
{
    throw "Graph runtime did not load Invoke-GraphRequest. Aborting."
}

Write-Host "`nConnecting to Microsoft Graph..." -ForegroundColor Cyan
try
{
    $org = Invoke-GraphRequest "/organization"
    Write-Host "Connected to tenant: $($org.value[0].displayName) ($($org.value[0].id))" -ForegroundColor Green
}
catch
{
    throw "Failed to connect to Graph. Ensure auth parameters are correct. Error: $_"
}
#endregion

Clear-Host
Write-Host "========================================" -ForegroundColor Cyan
Write-Host "  Intune Bulk Device Operations" -ForegroundColor Cyan
Write-Host "========================================" -ForegroundColor Cyan

if($WhatIf)
{
    Write-Host "`n*** DRY-RUN MODE ENABLED ***" -ForegroundColor Magenta
    Write-Host "No destructive actions will be performed." -ForegroundColor Magenta
}

#region Action selection
$action = Select-MenuItem -Items @("Delete","Retire","Wipe (Factory Reset)","Remote Lock","Sync") -Header "Select device operation"
if(-not $action) { Write-Host "Cancelled." -ForegroundColor Yellow; exit 0 }

$actionValue = switch($action)
{
    "Delete" { "delete" }
    "Retire" { "retire" }
    "Wipe (Factory Reset)" { "wipe" }
    "Remote Lock" { "remoteLock" }
    "Sync" { "syncDevice" }
}
#endregion

#region Load devices with filtering
Write-Host "`nLoading managed devices..." -ForegroundColor Cyan
$deviceUrl = "/deviceManagement/managedDevices?`$select=id,deviceName,operatingSystem,complianceState,lastSyncDateTime,azureADDeviceId,azureADRegistered,isEncrypted,userPrincipalName,ownerType,managementState&`$orderby=deviceName"
$devicesResponse = Invoke-GraphRequest $deviceUrl
$devices = $devicesResponse.value | Where-Object { $_.deviceName } | Sort-Object deviceName
Write-Host "Found $($devices.Count) devices." -ForegroundColor Green

# Filters
Write-Host "`n--- Apply Filters ---" -ForegroundColor Cyan
$osFilter = Read-Host "Filter by OS (Windows, iOS, macOS, Android — or press Enter for all)"
if(-not [string]::IsNullOrWhiteSpace($osFilter))
{
    $devices = $devices | Where-Object { $_.operatingSystem -like "*$osFilter*" }
}

$complianceFilter = Select-MenuItem -Items @("(all)","compliant","noncompliant","unknown","notApplicable","remediated","error","conflict") -Header "Filter by compliance state"
if($complianceFilter -and $complianceFilter -ne "(all)")
{
    $devices = $devices | Where-Object { $_.complianceState -eq $complianceFilter }
}

$daysInactive = Read-Host "Only show devices inactive for more than N days (press Enter to skip)"
if(-not [string]::IsNullOrWhiteSpace($daysInactive) -and $daysInactive -match "^\d+$")
{
    $cutoff = (Get-Date).AddDays(-[int]$daysInactive)
    $devices = $devices | Where-Object { [datetime]$_.lastSyncDateTime -lt $cutoff }
}

$nameFilter = Read-Host "Filter by device name (partial match, press Enter to skip)"
if(-not [string]::IsNullOrWhiteSpace($nameFilter))
{
    $devices = $devices | Where-Object { $_.deviceName -like "*$nameFilter*" }
}

Write-Host "`nFiltered to $($devices.Count) devices." -ForegroundColor Green

if($devices.Count -eq 0)
{
    Write-Host "No devices match filters. Exiting." -ForegroundColor Yellow
    exit 0
}

$deviceDisplays = $devices | ForEach-Object { "$($_.deviceName) | $($_.operatingSystem) | $($_.complianceState) | $($_.userPrincipalName) [$($_.id)]" }
$selectedDisplays = Select-MenuItem -Items $deviceDisplays -Header "Select devices (multi-select)" -Multi
if(-not $selectedDisplays)
{
    Write-Host "No devices selected. Exiting." -ForegroundColor Yellow
    exit 0
}

$selectedDevices = @()
foreach($disp in $selectedDisplays)
{
    $id = $disp -replace '.*\[(.*?)\]$', '$1'
    $dev = $devices | Where-Object { $_.id -eq $id } | Select-Object -First 1
    if($dev) { $selectedDevices += $dev }
}
Write-Host "Selected $($selectedDevices.Count) devices." -ForegroundColor Green
#endregion

#region Safeguards
$excludeHybrid = Read-YesNo -Prompt "Exclude hybrid Azure AD joined devices?" -Default $true
if($excludeHybrid)
{
    $preCount = $selectedDevices.Count
    # We need ownerType or join type info. managedDevices doesn't always expose hybrid directly,
    # but azureADRegistered + ownerType can help. We'll check azureADDeviceId against devices endpoint for joinType.
    Write-Host "`nChecking device join types..." -ForegroundColor Cyan
    $aadDeviceIds = $selectedDevices | Where-Object { $_.azureADDeviceId } | Select-Object -ExpandProperty azureADDeviceId -Unique
    $hybridIds = @{}
    foreach($aadId in $aadDeviceIds)
    {
        try
        {
            $aadDevice = Invoke-GraphRequest "/devices?`$filter=deviceId eq '$aadId'&`$select=id,displayName,joinType"
            if($aadDevice.value -and $aadDevice.value[0].joinType -eq "hybridAzureADJoin")
            {
                $hybridIds[$aadId] = $true
            }
        }
        catch { }
    }
    $selectedDevices = $selectedDevices | Where-Object { -not $hybridIds[$_.azureADDeviceId] }
    $excluded = $preCount - $selectedDevices.Count
    if($excluded -gt 0)
    {
        Write-Host "Excluded $excluded hybrid-joined device(s)." -ForegroundColor Yellow
    }
}

if($selectedDevices.Count -eq 0)
{
    Write-Host "No devices remaining after safeguards. Exiting." -ForegroundColor Yellow
    exit 0
}
#endregion

#region Review
Clear-Host
Write-Host "Review operation:" -ForegroundColor Green
Write-Host "  Action    : $action"
Write-Host "  Devices   : $($selectedDevices.Count)"
foreach($d in $selectedDevices)
{
    Write-Host "             - $($d.deviceName) ($($d.operatingSystem)) | $($d.userPrincipalName)"
}

$confirmText = switch($actionValue)
{
    "delete" { "PERMANENTLY DELETE" }
    "wipe" { "FACTORY RESET" }
    default { $action.ToUpper() }
}

$confirm = Read-Host "`nType '$confirmText' to confirm, or press Enter to cancel"
if($confirm -ne $confirmText)
{
    Write-Host "Cancelled." -ForegroundColor Yellow
    exit 0
}
#endregion

#region Execute
$success = 0
$failed = 0

foreach($dev in $selectedDevices)
{
    Write-Host "`nProcessing: $($dev.deviceName)" -ForegroundColor Cyan -NoNewline
    try
    {
        if($WhatIf)
        {
            Write-Host " [WHATIF: $actionValue]" -ForegroundColor Magenta
            $success++
            continue
        }

        if($actionValue -in @("delete","retire","remoteLock","syncDevice"))
        {
            $url = "/deviceManagement/managedDevices/$($dev.id)/$actionValue"
            $null = Invoke-GraphRequest $url -HttpMethod POST
        }
        elseif($actionValue -eq "wipe")
        {
            # Wipe supports keepEnrollmentData / keepUserData flags
            $keepEnrollment = Read-YesNo -Prompt "Keep enrollment data for $($dev.deviceName)?" -Default $false
            $keepUserData = Read-YesNo -Prompt "Keep user data for $($dev.deviceName)?" -Default $false
            $body = @{
                keepEnrollmentData = $keepEnrollment
                keepUserData = $keepUserData
                macOsUnlockCode = ""
            } | ConvertTo-Json -Compress
            $null = Invoke-GraphRequest "/deviceManagement/managedDevices/$($dev.id)/wipe" -HttpMethod POST -Content $body
        }

        Write-Host " -> OK" -ForegroundColor Green
        $success++
    }
    catch
    {
        Write-Host " -> ERROR: $($_.Exception.Message)" -ForegroundColor Red
        $failed++
    }
}

Write-Host "`n========================================" -ForegroundColor Cyan
Write-Host "  Bulk Device Operations Complete" -ForegroundColor Cyan
Write-Host "========================================" -ForegroundColor Cyan
Write-Host "  Success : $success"
Write-Host "  Failed  : $failed"
#endregion