# ==============================================================================
# Script Name: 8x8_Work_Updater.ps1
# Description: Downloads 8x8 with a progress bar, triggers a blocking 1-hour 
#              popup alert, silently installs, and launches 8x8 under the standard 
#              user session via Explorer.
# ==============================================================================

# Ensure script is running elevated
if (-not ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole]::Administrator)) {
    Write-Error "This script must be executed with Administrator privileges."
    exit 1
}

# Load required .NET assemblies
Add-Type -AssemblyName System.Net.Http

$workDir       = "C:\ProgramData\JCT600_8x8Update"
$installerPath = Join-Path $workDir "8x8_Work_Installer.msi"
$vbsAlertPath  = Join-Path $workDir "ShowUserAlert.vbs"

if (-not (Test-Path $workDir)) {
    New-Item -Path $workDir -ItemType Directory -Force | Out-Null
}

try {
    # --------------------------------------------------------------------------
    # Step 1: Download 8x8 Setup Installer with Console Progress Bar
    # --------------------------------------------------------------------------
    $installerUrl = "https://work-desktop-assets.8x8.com/prod-publish/ga/work-64-msi-v8.35.2-6.msi"
    Write-Host "[1/4] Downloading 8x8 Work installer..." -ForegroundColor Cyan

    try {
        $httpClient = New-Object System.Net.Http.HttpClient
        $response = $httpClient.GetAsync($installerUrl, [System.Net.Http.HttpCompletionOption]::ResponseHeadersRead).Result
        
        if (-not $response.IsSuccessStatusCode) { throw "HTTP Error $($response.StatusCode)" }

        $totalBytes = $response.Content.Headers.ContentLength
        $inputStream = $response.Content.ReadAsStreamAsync().Result
        $outputStream = [System.IO.File]::Create($installerPath)
        $buffer = New-Object byte[] 8192
        $totalBytesRead = 0; $bytesRead = 0

        while (($bytesRead = $inputStream.Read($buffer, 0, $buffer.Length)) -gt 0) {
            $outputStream.Write($buffer, 0, $bytesRead)
            $totalBytesRead += $bytesRead

            if ($totalBytes -gt 0) {
                $percent = [math]::Round(($totalBytesRead / $totalBytes) * 100)
                $downloadedMB = [math]::Round($totalBytesRead / 1MB, 2)
                $totalMB = [math]::Round($totalBytes / 1MB, 2)
                $barLength = 30
                $filledLength = [math]::Round(($percent / 100) * $barLength)
                $bar = ("█" * $filledLength) + ("░" * ($barLength - $filledLength))

                Write-Host "`rDownloading: [$bar] $percent% ($downloadedMB MB / $totalMB MB)" -NoNewline -ForegroundColor Yellow
            }
        }
        $outputStream.Close(); $inputStream.Close(); $httpClient.Dispose()
        Write-Host "`nDownload complete: $installerPath" -ForegroundColor Green
    } catch {
        Write-Error "`nFailed to download installer. Error: $_"
        exit 1
    }

    # --------------------------------------------------------------------------
    # Step 2: Trigger Blocking Interactive Popup (Waits for Click or 1 Hour)
    # --------------------------------------------------------------------------
    Write-Host "[2/4] Triggering interactive alert on active user's desktop..." -ForegroundColor Cyan

    # Generate a blocking VBScript WshShell.Popup (Type 48 = Exclamation, 4096 = System Modal / Always on top)
    $vbsContent = @"
Set wshShell = CreateObject("WScript.Shell")
intButton = wshShell.Popup("An automatic update for 8x8 Work has been scheduled by JCT600 IT Support." & vbCrLf & vbCrLf & "Please save active work and finish ongoing calls." & vbCrLf & vbCrLf & "Click OK or close this window to update immediately, or wait for the 1-hour timer.", 3600, "JCT600 IT Support — 8x8 Work Update", 48 + 4096)
"@
    
    [System.IO.File]::WriteAllText($vbsAlertPath, $vbsContent, [System.Text.Encoding]::ASCII)

    # Launch popup and WAIT for user click or 3600-second timeout
    Write-Host "Waiting for user acknowledgment or 1-hour timeout..." -ForegroundColor Yellow
    $popupProcess = Start-Process "wscript.exe" -ArgumentList "`"$vbsAlertPath`"" -Wait -PassThru

    # --------------------------------------------------------------------------
    # Step 3: Close Running 8x8 Processes & Install Silently
    # --------------------------------------------------------------------------
    Write-Host "[3/4] Stopping 8x8 processes and installing silently..." -ForegroundColor Cyan

    $targetProcesses = Get-Process | Where-Object { 
        $_.ProcessName -like "*8x8*" -or $_.MainWindowTitle -like "*8x8*" 
    }

    if ($targetProcesses) {
        foreach ($proc in $targetProcesses) {
            Stop-Process -Id $proc.Id -Force -ErrorAction SilentlyContinue
        }
        Start-Sleep -Seconds 3
    }

    $msiArgs = "/i `"$installerPath`" /quiet /norestart"
    $installJob = Start-Process msiexec.exe -ArgumentList $msiArgs -Wait -PassThru

    if ($installJob.ExitCode -ne 0 -and $installJob.ExitCode -ne 3010) {
        Write-Error "Installation failed with exit code $($installJob.ExitCode)."
        exit $installJob.ExitCode
    }

    Write-Host "Installation completed successfully." -ForegroundColor Green

    # --------------------------------------------------------------------------
    # Step 4: Launch 8x8 Work via Explorer (User Context)
    # --------------------------------------------------------------------------
    Write-Host "[4/4] Launching 8x8 Work in user session..." -ForegroundColor Cyan

    $possiblePaths = @(
        "${env:ProgramFiles}\8x8 Inc\8x8 Work\8x8 Work.exe",
        "${env:ProgramFiles(x86)}\8x8 Inc\8x8 Work\8x8 Work.exe",
        "${env:ProgramFiles}\8x8 Work\8x8 Work.exe",
        "$env:LocalAppData\Programs\8x8 Work\8x8 Work.exe"
    )

    $exePath = $possiblePaths | Where-Object { Test-Path $_ } | Select-Object -First 1

    if ($exePath) {
        # Using explorer.exe to launch the executable forces Windows to run 8x8 in 
        # the interactive standard user's desktop context, preventing GPU crashes.
        Start-Process "explorer.exe" -ArgumentList "`"$exePath`""
        Write-Host "8x8 Work launched successfully." -ForegroundColor Green
    } else {
        Write-Warning "Could not locate 8x8 Work executable."
    }

} finally {
    Write-Host "Cleaning up temporary files..." -ForegroundColor Gray
    if (Test-Path $workDir) { Remove-Item $workDir -Recurse -Force -ErrorAction SilentlyContinue }
}