import { $ } from "bun";
import { tmpdir } from "os";
import { join } from "path";
import type { Platform, WindowInfo, DisplayInfo } from "../types.ts";
// PowerShell script to list windows using Win32 API
const LIST_WINDOWS_SCRIPT = `
Add-Type @"
using System;
using System.Runtime.InteropServices;
using System.Text;
using System.Collections.Generic;
public class WindowHelper {
[DllImport("user32.dll")]
public static extern bool EnumWindows(EnumWindowsProc lpEnumFunc, IntPtr lParam);
[DllImport("user32.dll")]
public static extern bool IsWindowVisible(IntPtr hWnd);
[DllImport("user32.dll", CharSet = CharSet.Auto)]
public static extern int GetWindowText(IntPtr hWnd, StringBuilder lpString, int nMaxCount);
[DllImport("user32.dll")]
public static extern int GetWindowTextLength(IntPtr hWnd);
[DllImport("user32.dll")]
public static extern bool GetWindowRect(IntPtr hWnd, out RECT lpRect);
[DllImport("user32.dll", SetLastError = true)]
public static extern uint GetWindowThreadProcessId(IntPtr hWnd, out uint lpdwProcessId);
[DllImport("user32.dll")]
public static extern IntPtr GetShellWindow();
public delegate bool EnumWindowsProc(IntPtr hWnd, IntPtr lParam);
[StructLayout(LayoutKind.Sequential)]
public struct RECT {
public int Left;
public int Top;
public int Right;
public int Bottom;
}
public static List<object> GetWindows() {
var windows = new List<object>();
IntPtr shellWindow = GetShellWindow();
EnumWindows((hWnd, lParam) => {
if (hWnd == shellWindow) return true;
if (!IsWindowVisible(hWnd)) return true;
int length = GetWindowTextLength(hWnd);
if (length == 0) return true;
StringBuilder sb = new StringBuilder(length + 1);
GetWindowText(hWnd, sb, sb.Capacity);
string title = sb.ToString();
RECT rect;
GetWindowRect(hWnd, out rect);
// Skip windows with zero size
if (rect.Right - rect.Left <= 0 || rect.Bottom - rect.Top <= 0) return true;
uint processId;
GetWindowThreadProcessId(hWnd, out processId);
string appName = "";
try {
var process = System.Diagnostics.Process.GetProcessById((int)processId);
appName = process.ProcessName;
} catch {}
windows.Add(new {
id = hWnd.ToString(),
title = title,
app = appName,
x = rect.Left,
y = rect.Top,
width = rect.Right - rect.Left,
height = rect.Bottom - rect.Top
});
return true;
}, IntPtr.Zero);
return windows;
}
}
"@
$windows = [WindowHelper]::GetWindows()
$result = $windows | ForEach-Object {
@{
id = $_.id
title = $_.title
app = $_.app
bounds = @{
x = $_.x
y = $_.y
width = $_.width
height = $_.height
}
}
}
$result | ConvertTo-Json -Compress
`;
// PowerShell script to list displays
const LIST_DISPLAYS_SCRIPT = `
Add-Type -AssemblyName System.Windows.Forms
$screens = [System.Windows.Forms.Screen]::AllScreens
$result = @()
$i = 1
foreach ($screen in $screens) {
$result += @{
id = $i
name = $screen.DeviceName
primary = $screen.Primary
bounds = @{
x = $screen.Bounds.X
y = $screen.Bounds.Y
width = $screen.Bounds.Width
height = $screen.Bounds.Height
}
}
$i++
}
$result | ConvertTo-Json -Compress
`;
// PowerShell script to capture a window by handle
function getWindowCaptureScript(windowId: string, outputPath: string): string {
return `
Add-Type @"
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Runtime.InteropServices;
public class ScreenCapture {
[DllImport("user32.dll")]
public static extern bool GetWindowRect(IntPtr hWnd, out RECT lpRect);
[DllImport("user32.dll")]
public static extern bool PrintWindow(IntPtr hWnd, IntPtr hdcBlt, int nFlags);
[StructLayout(LayoutKind.Sequential)]
public struct RECT {
public int Left, Top, Right, Bottom;
}
public static void CaptureWindow(IntPtr hWnd, string path) {
RECT rect;
GetWindowRect(hWnd, out rect);
int width = rect.Right - rect.Left;
int height = rect.Bottom - rect.Top;
using (Bitmap bmp = new Bitmap(width, height, PixelFormat.Format32bppArgb)) {
using (Graphics g = Graphics.FromImage(bmp)) {
IntPtr hdcBitmap = g.GetHdc();
PrintWindow(hWnd, hdcBitmap, 2); // PW_RENDERFULLCONTENT = 2
g.ReleaseHdc(hdcBitmap);
}
bmp.Save(path, ImageFormat.Png);
}
}
}
"@
[ScreenCapture]::CaptureWindow([IntPtr]${windowId}, "${outputPath.replace(/\\/g, "\\\\")}")
`;
}
// PowerShell script to capture screen region
function getScreenCaptureScript(x: number, y: number, width: number, height: number, outputPath: string): string {
return `
Add-Type -AssemblyName System.Windows.Forms
Add-Type -AssemblyName System.Drawing
$bounds = [Drawing.Rectangle]::new(${x}, ${y}, ${width}, ${height})
$bmp = New-Object Drawing.Bitmap($bounds.Width, $bounds.Height)
$graphics = [Drawing.Graphics]::FromImage($bmp)
$graphics.CopyFromScreen($bounds.Location, [Drawing.Point]::Empty, $bounds.Size)
$bmp.Save("${outputPath.replace(/\\/g, "\\\\")}", [Drawing.Imaging.ImageFormat]::Png)
$graphics.Dispose()
$bmp.Dispose()
`;
}
async function runPowerShell(script: string): Promise<string> {
const result = await $`powershell -NoProfile -ExecutionPolicy Bypass -Command ${script}`.text();
return result.trim();
}
async function listWindows(): Promise<WindowInfo[]> {
try {
const result = await runPowerShell(LIST_WINDOWS_SCRIPT);
if (!result || result === "null") return [];
const parsed = JSON.parse(result);
// Handle single window case (PowerShell returns object instead of array)
return Array.isArray(parsed) ? parsed : [parsed];
} catch {
return [];
}
}
async function listDisplays(): Promise<DisplayInfo[]> {
try {
const result = await runPowerShell(LIST_DISPLAYS_SCRIPT);
if (!result || result === "null") return getDefaultDisplay();
const parsed = JSON.parse(result);
return Array.isArray(parsed) ? parsed : [parsed];
} catch {
return getDefaultDisplay();
}
}
function getDefaultDisplay(): DisplayInfo[] {
return [
{
id: 1,
name: "Primary Display",
primary: true,
bounds: { x: 0, y: 0, width: 1920, height: 1080 },
},
];
}
async function screenshotWindow(windowId: string): Promise<Buffer> {
const tmpFile = join(tmpdir(), `screenshot-${Date.now()}.png`);
await runPowerShell(getWindowCaptureScript(windowId, tmpFile));
const buffer = await Bun.file(tmpFile).arrayBuffer();
await $`del "${tmpFile}"`.quiet();
return Buffer.from(buffer);
}
async function screenshotScreen(displayId?: number): Promise<Buffer> {
const displays = await listDisplays();
let bounds = { x: 0, y: 0, width: 1920, height: 1080 };
if (displayId !== undefined) {
const display = displays.find(d => d.id === displayId);
if (display) {
bounds = display.bounds;
}
} else {
// Capture primary or first display
const primary = displays.find(d => d.primary) || displays[0];
if (primary) {
bounds = primary.bounds;
}
}
const tmpFile = join(tmpdir(), `screenshot-${Date.now()}.png`);
await runPowerShell(getScreenCaptureScript(bounds.x, bounds.y, bounds.width, bounds.height, tmpFile));
const buffer = await Bun.file(tmpFile).arrayBuffer();
await $`del "${tmpFile}"`.quiet();
return Buffer.from(buffer);
}
async function screenshotRegion(
x: number,
y: number,
width: number,
height: number
): Promise<Buffer> {
const tmpFile = join(tmpdir(), `screenshot-${Date.now()}.png`);
await runPowerShell(getScreenCaptureScript(x, y, width, height, tmpFile));
const buffer = await Bun.file(tmpFile).arrayBuffer();
await $`del "${tmpFile}"`.quiet();
return Buffer.from(buffer);
}
export const win32: Platform = {
listWindows,
listDisplays,
screenshotWindow,
screenshotScreen,
screenshotRegion,
};
