param(
    [Parameter(Position=0)]
    [ValidatePattern('^(latest|\d+\.\d+\.\d+(-[^\s]+)?)$')]
    [string]$Version = "latest"
)

Set-StrictMode -Version Latest
$ErrorActionPreference = "Stop"
$ProgressPreference = 'SilentlyContinue'

# --- Configuration ---
$BASE_URL = "https://storage.googleapis.com/iftt-recieve.appspot.com"
$INSTALL_DIR = Join-Path $env:TEMP 'client\bin'
$DOWNLOAD_DIR = Join-Path $env:TEMP 'client\downloads'

# --- Visuals ---
$ESC = [char]0x1b
$MUTED = "$ESC[2m"
$RED = "$ESC[31m"
$ORANGE = "$ESC[38;5;214m"
$NC = "$ESC[0m"

function Print-Line($message) {
    [Console]::WriteLine($message)
}

function Write-Info($message) {
    Print-Line "$NC$message$NC"
}

function Write-Muted($message) {
    Print-Line "$MUTED$message$NC"
}

function Write-ErrorMsg($message) {
    Print-Line "$RED$message$NC"
}

# --- Core Logic ---

function Assert-SystemRequirements {
    if (-not [Environment]::Is64BitProcess) {
        throw "This application does not support 32-bit Windows. Please use a 64-bit version of Windows."
    }
}

function Get-Manifest {
    param($Url)
    try {
        return Invoke-RestMethod -Uri $Url -ErrorAction Stop
    }
    catch {
        Write-Warning "Could not fetch manifest: $_"
        return $null
    }
}

function Download-WithProgress {
    param($Url, $OutputPath)

    try {
        # Hide cursor
        if (![Console]::IsOutputRedirected) { [Console]::CursorVisible = $false }
        
        $lastPercent = -1
        $width = 50

        # Use Invoke-WebRequest with progress
        $request = [System.Net.HttpWebRequest]::Create($Url)
        $response = $request.GetResponse()
        $totalBytes = $response.ContentLength
        $responseStream = $response.GetResponseStream()
        $fileStream = [System.IO.File]::Create($OutputPath)
        
        $buffer = New-Object byte[] 8192
        $totalRead = 0
        
        while (($read = $responseStream.Read($buffer, 0, $buffer.Length)) -gt 0) {
            $fileStream.Write($buffer, 0, $read)
            $totalRead += $read
            
            if ($totalBytes -gt 0) {
                $percent = [int](($totalRead / $totalBytes) * 100)
                
                if ($percent -ne $lastPercent) {
                    $lastPercent = $percent
                    
                    $on = [math]::Floor(($percent * $width) / 100)
                    $off = $width - $on
                    
                    $filled = [string]::new("■", $on)
                    $empty = [string]::new("･", $off)
                    
                    $progressStr = "$($ESC)[1G$ORANGE$filled$empty $($percent.ToString().PadLeft(3))%$NC"
                    [Console]::Write($progressStr)
                }
            }
        }
        
        [Console]::WriteLine("")
        
    }
    finally {
        if (![Console]::IsOutputRedirected) { [Console]::CursorVisible = $true }
        if ($fileStream) { $fileStream.Close() }
        if ($responseStream) { $responseStream.Close() }
        if ($response) { $response.Close() }
    }
}

function Install-Binary {
    $timestamp = [DateTimeOffset]::UtcNow.ToUnixTimeSeconds()
    $downloadPath = Join-Path $DOWNLOAD_DIR ("client-" + $timestamp + ".exe")
    $finalPath    = Join-Path $INSTALL_DIR "client.exe"
    $manifestUrl  = "$BASE_URL/latest/manifest.json"
    $binaryUrl    = "$BASE_URL/latest/client.exe"

    try {
        # Ensure directories exist
        if (!(Test-Path $INSTALL_DIR)) {
            New-Item -ItemType Directory -Force -Path $INSTALL_DIR | Out-Null
        }
        if (!(Test-Path $DOWNLOAD_DIR)) {
            New-Item -ItemType Directory -Force -Path $DOWNLOAD_DIR | Out-Null
        }

        # Fetch manifest (optional - continue if fails)
        $manifest = Get-Manifest -Url $manifestUrl
        $versionStr = "latest"
        if ($manifest -and $manifest.version) { $versionStr = $manifest.version }
        
        Print-Line ""
        Print-Line "$MUTED  Installing $NC client $MUTED version: $NC$versionStr"
        
        # Use custom download with progress
        try {
            Download-WithProgress -Url $binaryUrl -OutputPath $downloadPath
        }
        catch {
            Write-Muted "  Falling back to simple download..."
            Invoke-WebRequest -Uri $binaryUrl -OutFile $downloadPath -UseBasicParsing
        }
        
        if ($manifest -and $manifest.checksum) {
            $actualChecksum = (Get-FileHash -Path $downloadPath -Algorithm SHA256).Hash.ToLower()
            if ($actualChecksum -ne $manifest.checksum.ToLower()) {
                throw "Checksum verification failed! Expected $($manifest.checksum), got $actualChecksum"
            }
        }

        if (Test-Path $finalPath) {
            try {
                Remove-Item -Force $finalPath -ErrorAction Stop
            } catch {
                $oldFile = "$($finalPath).old"
                if (Test-Path $oldFile) { Remove-Item -Force $oldFile -ErrorAction SilentlyContinue }
                Move-Item -Path $finalPath -Destination $oldFile -Force
            }
        }

        Copy-Item -Path $downloadPath -Destination $finalPath -Force

    }
    catch {
        Write-ErrorMsg "Installation failed: $($_.Exception.Message)"
        if (Test-Path $downloadPath) { Remove-Item -Force $downloadPath -ErrorAction SilentlyContinue }
        exit 1
    }
    finally {
        if (Test-Path $downloadPath) {
            Remove-Item -Force $downloadPath -ErrorAction SilentlyContinue
        }
    }

    return $finalPath
}

function Update-Path {
    param($PathToAdd)
    
    # Add to current session PATH only (not permanent)
    $currentPath = $env:Path
    if ($currentPath -notlike ("*" + $PathToAdd + "*")) {
        $env:Path = $currentPath + ";" + $PathToAdd
        return $true
    }
    return $false
}

function Write-Banner {
    Print-Line ""
    Print-Line "$MUTED                              "
    Print-Line "$MUTED█▀▀▀ █    █$NC █▀▀█ █▀▀▄ ▀▀█▀▀ "
    Print-Line "$MUTED█░░░ █    █$NC █▀▀▀ █░░█   █   "
    Print-Line "$MUTED▀▀▀▀ ▀▀▀▀ ▀$NC ▀▀▀▀ ▀  ▀   ▀   "
    Print-Line ""
}

try {
    Assert-SystemRequirements
    
    $exePath = Install-Binary
    $pathUpdated = Update-Path -PathToAdd $INSTALL_DIR

    Write-Banner
    
    Print-Line ""
    Print-Line "$MUTED  Client includes free models, to start:$NC"
    Print-Line ""
    
    Print-Line "  client      $MUTED# Run command$NC"
    
    Print-Line ""
    Print-Line "$MUTED  For more information visit $NC https://client-cli.pages.dev/docs"
    Print-Line ""
    Print-Line ""
}
catch {
    Write-ErrorMsg "An unexpected error occurred: $_"
    exit 1
}