#Requires -Version 5.1
[CmdletBinding(SupportsShouldProcess)]
param(
    [Parameter(Mandatory)][string]$InstallerPath
)

$ErrorActionPreference = 'Stop'
$identity = [Security.Principal.WindowsIdentity]::GetCurrent()
$principal = [Security.Principal.WindowsPrincipal]::new($identity)
if (-not $principal.IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)) {
    throw 'Run the FSLogix installer from an elevated Windows PowerShell session.'
}

$appsRoot = Join-Path $env:ProgramFiles 'FSLogix\Apps'
$frxPath = Join-Path $appsRoot 'frx.exe'
$service = Get-Service -Name frxsvc -ErrorAction SilentlyContinue
if ($service -and (Test-Path -LiteralPath $frxPath -PathType Leaf)) {
    $versionOutput = @(& $frxPath version 2>&1) -join [Environment]::NewLine
    return [pscustomobject]@{
        Installed = $true
        Changed = $false
        RestartRequired = $false
        Service = $service.Status.ToString()
        Version = $versionOutput.Trim()
    }
}

if (-not (Test-Path -LiteralPath $InstallerPath -PathType Leaf)) {
    throw "FSLogixAppsSetup.exe was not found: $InstallerPath"
}
$resolvedInstaller = (Resolve-Path -LiteralPath $InstallerPath).Path
if ([IO.Path]::GetFileName($resolvedInstaller) -ne 'FSLogixAppsSetup.exe') {
    throw 'InstallerPath must identify the Microsoft FSLogix core installer named FSLogixAppsSetup.exe.'
}
$signature = Get-AuthenticodeSignature -LiteralPath $resolvedInstaller
if ($signature.Status -ne [Management.Automation.SignatureStatus]::Valid -or
    -not $signature.SignerCertificate -or
    $signature.SignerCertificate.Subject -notmatch '(^|,\s*)CN=Microsoft Corporation(,|$)') {
    throw 'FSLogixAppsSetup.exe must have a valid Microsoft Corporation Authenticode signature.'
}

$logRoot = Join-Path $env:ProgramData 'SGU\FSLogix'
$logPath = Join-Path $logRoot 'install.log'
if (-not $PSCmdlet.ShouldProcess($env:COMPUTERNAME, 'Install Microsoft FSLogix Apps without restarting')) {
    return
}
New-Item -ItemType Directory -Path $logRoot -Force | Out-Null
$process = Start-Process -FilePath $resolvedInstaller `
    -ArgumentList @('/install', '/quiet', '/norestart', '/log', "`"$logPath`"") `
    -Wait -PassThru -WindowStyle Hidden
if ($process.ExitCode -notin @(0, 1641, 3010)) {
    throw "FSLogix installation failed with exit code $($process.ExitCode). Review $logPath."
}

$service = Get-Service -Name frxsvc -ErrorAction SilentlyContinue
if (-not $service -or -not (Test-Path -LiteralPath $frxPath -PathType Leaf)) {
    throw "FSLogix installation did not create the frxsvc service and frx.exe. Review $logPath."
}
$versionOutput = @(& $frxPath version 2>&1) -join [Environment]::NewLine
[pscustomobject]@{
    Installed = $true
    Changed = $true
    RestartRequired = $true
    Service = $service.Status.ToString()
    Version = $versionOutput.Trim()
    LogPath = $logPath
}