param(
    [string]$configFile = "$PSScriptRoot\MSIProperties.json"
)

$ErrorActionPreference = "Stop"
$logPath = "$env:windir\Temp\InstallStatus.log"

Start-Sleep -Seconds 60

try {
    if (-not (Test-Path -LiteralPath $configFile)) {
        Add-Content -Path $logPath -Value "[$(Get-Date -Format u)] Config file not found: $configFile"
        exit 1
    }

    $config = Get-Content -LiteralPath $configFile -Raw | ConvertFrom-Json
    $expectedVersion = [string]$config.expectedVersion

    $regKey = "HKLM:\SOFTWARE\ManageEngine\FAP"

    if ([Environment]::Is64BitOperatingSystem) {
        $productCode = "{859C3CA2-0CD2-4A38-8993-07D53F581E40}"
        $msiFile = "$PSScriptRoot\DataSecurityPlusAgent-x64.msi"
    }
    else {
        $productCode = ""
        $msiFile = "$PSScriptRoot\DataSecurityPlusAgent-x86.msi"
    }

    if (-not (Test-Path -LiteralPath $msiFile)) {
        Add-Content -Path $logPath -Value "[$(Get-Date -Format u)] MSI not found: $msiFile"
        exit 2
    }

    if (Test-Path $regKey) {
        try {
            $installedVersion = [string](Get-ItemProperty $regKey).Build
            if ($installedVersion -ge $expectedVersion) {
                Add-Content -Path $logPath -Value "[$(Get-Date -Format u)] Installed version ($installedVersion) >= expected ($expectedVersion). Skipping."
                exit 0
            }

            Add-Content -Path $logPath -Value "[$(Get-Date -Format u)] Uninstalling version $installedVersion"
            if ($productCode) {
                $u = Start-Process -FilePath "msiexec.exe" -ArgumentList "/x $productCode /qn /norestart /l*v C:\Windows\Temp\DSP_Uninstall.log" -Wait -PassThru
                Add-Content -Path $logPath -Value "[$(Get-Date -Format u)] Uninstall exit code: $($u.ExitCode)"
            }
        }
        catch {
            Add-Content -Path $logPath -Value "[$(Get-Date -Format u)] Failed to read uninstall info: $($_.Exception.Message)"
        }
    }

    $msiArgs = @(
        "/i `"$msiFile`"",
        "PROTOCOL=$($config.PROTOCOL)",
        "PORT=$($config.PORTNO)",
        "SERVERNAME=$($config.SERVERNAME)",
        "FQDN=$($config.FQDN)",
        "SERVERIP=$($config.SERVERIP)",
        "ISENDPOINTAUTOINSTALLREQUIRED=$($config.ENDPOINTAUTOINSTALLREQUIRED)",
        "AGENTINSTALLATIONKEY=$($config.AGENTINSTALLATIONKEY)",
        "/qn /norestart /l*v C:\Windows\Temp\DSP_Install.log"
    ) -join " "

    $p = Start-Process -FilePath "msiexec.exe" -ArgumentList $msiArgs -Wait -PassThru
    Add-Content -Path $logPath -Value "[$(Get-Date -Format u)] Install exit code: $($p.ExitCode)"
    exit $p.ExitCode
}
catch {
    Add-Content -Path $logPath -Value "[$(Get-Date -Format u)] Fatal error: $($_.Exception.Message)"
    exit 99
}