import { execFile } from "node:child_process";
import { promisify } from "node:util";
import fs from "node:fs";

import path from "node:path";
import { app, BrowserWindow, screen } from "electron";
import { RuntimeError } from "./engine/types";

const run = promisify(execFile);

function pickerScriptPath(): string {
  const candidates = [
    path.join(process.resourcesPath || "", "desktop-picker.ps1"),
    path.join(app.getAppPath(), "resources", "desktop-picker.ps1")
  ].filter(Boolean);
  const found = candidates.find(p => fs.existsSync(p));
  if (!found) throw new RuntimeError("picker_unavailable", "桌面拾取脚本缺失", { recommendation: "重新安装应用" });
  return found;
}
export interface DesktopPickResult {
  cancelled?: boolean;
  window?: string;
  name?: string;
  automationId?: string;
  controlType?: string;
  className?: string;
  selector: string;
}

export async function pickDesktopElement(): Promise<DesktopPickResult> {
  const appWindows = BrowserWindow.getAllWindows().filter(w => !w.isDestroyed());
  for (const w of appWindows) w.minimize();
  try {
    const { stdout } = await run("powershell.exe", ["-NoProfile", "-STA", "-ExecutionPolicy", "Bypass", "-File", pickerScriptPath()], { timeout: 180000, windowsHide: true, maxBuffer: 4 * 1024 * 1024 });
    const jsonLine = stdout.trim().split(/\r?\n/).reverse().find(l => l.trim().startsWith("{"));
    if (!jsonLine) throw new RuntimeError("picker_failed", "拾取未返回结果");
    const parsed = JSON.parse(jsonLine) as Omit<DesktopPickResult, "selector">;
    if (parsed.cancelled) return { ...parsed, selector: "" };
    const parts: string[] = [];
    if (parsed.window) parts.push("window=" + parsed.window);
    if (parsed.name) parts.push("name=" + parsed.name);
    if (parsed.controlType) parts.push("type=" + parsed.controlType);
    if (parsed.automationId) parts.push("id=" + parsed.automationId);
    return { ...parsed, selector: parts.join(";") };
  } finally {
    for (const w of appWindows) {
      if (!w.isDestroyed()) w.restore();
    }
  }
}
export async function listVisibleWindows(): Promise<Array<{ title: string; process: string }>> {
  const { stdout } = await run("powershell.exe", ["-NoProfile", "-ExecutionPolicy", "Bypass", "-File", pickerScriptPath(), "-Mode", "windows"], { timeout: 30000, windowsHide: true, maxBuffer: 4 * 1024 * 1024 });
  const jsonLine = stdout.trim().split(/\r?\n/).reverse().find(l => l.trim().startsWith("["));
  if (!jsonLine) return [];
  return JSON.parse(jsonLine) as Array<{ title: string; process: string }>;
}
export async function pickScreenRegion(): Promise<{ x: number; y: number; width: number; height: number; imagePath: string }> {
  const appWindows = BrowserWindow.getAllWindows().filter(w => !w.isDestroyed());
  for (const w of appWindows) w.minimize();
  const display = screen.getPrimaryDisplay();
  const sx = display.bounds.x, sy = display.bounds.y, sw = display.bounds.width, sh = display.bounds.height;
  const win = new BrowserWindow({
    x: sx, y: sy, width: sw, height: sh,
    frame: false, transparent: true, alwaysOnTop: true, skipTaskbar: true, resizable: false, movable: false,
    webPreferences: { contextIsolation: true, nodeIntegration: false, sandbox: true }
  });
  const htmlParts = [
    "<!DOCTYPE html><html><head><meta charset='utf-8'><style>",
    "html,body{margin:0;height:100%;background:rgba(0,30,80,0.25);cursor:crosshair;overflow:hidden}",
    "#sel{position:absolute;border:2px solid #2563eb;background:rgba(37,99,235,0.15);display:none}",
    "#tip{position:fixed;top:12px;left:50%;transform:translateX(-50%);color:#fff;background:rgba(0,0,0,0.65);padding:8px 18px;border-radius:6px;font-family:Microsoft YaHei;font-size:14px}",
    "</style></head><body>",
    "<div id=sel></div><div id=tip>拖拽框选区域，松开鼠标完成；Esc 取消</div>",
    "<script>",
    "var sel = document.getElementById('sel'); var start = null;",
    "document.addEventListener('mousedown', function(e) { start = [e.clientX, e.clientY]; sel.style.display = 'block'; sel.style.left = e.clientX + 'px'; sel.style.top = e.clientY + 'px'; sel.style.width = '0px'; sel.style.height = '0px'; });",
    "document.addEventListener('mousemove', function(e) { if (!start) return; sel.style.left = Math.min(start[0], e.clientX) + 'px'; sel.style.top = Math.min(start[1], e.clientY) + 'px'; sel.style.width = Math.abs(e.clientX - start[0]) + 'px'; sel.style.height = Math.abs(e.clientY - start[1]) + 'px'; });",
    "document.addEventListener('mouseup', function(e) { if (!start) return; window.__region = { x: Math.min(start[0], e.clientX), y: Math.min(start[1], e.clientY), width: Math.abs(e.clientX - start[0]), height: Math.abs(e.clientY - start[1]) }; window.__done = true; });",
    "document.addEventListener('keydown', function(e) { if (e.key === 'Escape') { window.__cancelled = true; window.__done = true; } });",
    "</script></body></html>"
  ];
  void win.loadURL("data:text/html;charset=utf-8," + encodeURIComponent(htmlParts.join("")));
  const deadline = Date.now() + 60000;
  let region: { x: number; y: number; width: number; height: number } | null = null;
  while (Date.now() < deadline) {
    await new Promise(r => setTimeout(r, 250));
    try {
      const state = await win.webContents.executeJavaScript("JSON.stringify({ done: window.__done === true, cancelled: window.__cancelled === true, region: window.__region || null })", true);
      const parsed = JSON.parse(state) as { done: boolean; cancelled: boolean; region: { x: number; y: number; width: number; height: number } | null };
      if (parsed.cancelled) { win.destroy(); throw new RuntimeError("pick_cancelled", "已取消框选"); }
      if (parsed.done && parsed.region && parsed.region.width > 2 && parsed.region.height > 2) { region = parsed.region; break; }
      if (parsed.done) break;
    } catch (error) {
      if ((error as Error).message.includes("已取消框选")) throw error;
    }
  }
  for (const w of appWindows) { if (!w.isDestroyed()) { w.show(); w.restore(); w.focus(); } }
  win.destroy();
  if (!region) throw new RuntimeError("pick_cancelled", "未完成框选");
  await new Promise(r => setTimeout(r, 300));
  const outDir = path.join(app.getPath("userData"), "region-picks");
  fs.mkdirSync(outDir, { recursive: true });
  const imagePath = path.join(outDir, `pick-region-${Date.now()}.png`);
  const psScript = [
    "Add-Type -AssemblyName System.Drawing | Out-Null;",
    "$bitmap = New-Object System.Drawing.Bitmap " + region.width + ", " + region.height + ";",
    "$graphics = [System.Drawing.Graphics]::FromImage();",
    "$graphics.CopyFromScreen(" + region.x + ", " + region.y + ", 0, 0, $bitmap.Size);",
    "$graphics.Dispose();",
    "$bitmap.Save(" + JSON.stringify(imagePath) + ");",
    "$bitmap.Dispose();",
    "Write-Output ok"
  ].join("");
  await run("powershell.exe", ["-NoProfile", "-NonInteractive", "-ExecutionPolicy", "Bypass", "-Command", psScript], { timeout: 30000, windowsHide: true });
  return { ...region, imagePath };
}