import { execFile } from "node:child_process";
import { promisify } from "node:util";
import { register } from "../engine/registry";
import { RuntimeError, type CapabilityHandler } from "../engine/types";

const execFileAsync = promisify(execFile);
const USER32 = `Add-Type @'
using System;
using System.Runtime.InteropServices;
public static class RpaUser32 {
  [DllImport("user32.dll")] public static extern bool SetCursorPos(int X, int Y);
  [DllImport("user32.dll")] public static extern void mouse_event(uint flags, uint dx, uint dy, uint data, UIntPtr extra);
  [DllImport("user32.dll")] public static extern IntPtr GetForegroundWindow();
  [DllImport("user32.dll", CharSet=CharSet.Unicode)] public static extern int GetWindowText(IntPtr hWnd, System.Text.StringBuilder text, int count);
  [DllImport("user32.dll")] public static extern bool SetForegroundWindow(IntPtr hWnd);
}
'@`;

function text(args: Record<string, unknown>, keys: string[], fallback = ""): string {
  for (const key of keys) {
    if (args[key] !== undefined && args[key] !== null && args[key] !== "") return String(args[key]);
  }
  return fallback;
}

function number(args: Record<string, unknown>, keys: string[], fallback = 0): number {
  const value = Number(text(args, keys, String(fallback)));
  return Number.isFinite(value) ? value : fallback;
}

function point(value: unknown): [number, number] {
  if (Array.isArray(value)) return [Number(value[0]) || 0, Number(value[1]) || 0];
  try {
    const parsed = JSON.parse(String(value || "[0,0]"));
    return point(parsed);
  } catch {
    const values = String(value || "").split(/[ ,，]+/).map(Number);
    return [values[0] || 0, values[1] || 0];
  }
}

function encoded(command: string): string {
  return Buffer.from(command, "utf16le").toString("base64");
}

export async function powershell(command: string, timeout = 30000): Promise<string> {
  try {
    const result = await execFileAsync("powershell.exe", ["-NoProfile", "-NonInteractive", "-ExecutionPolicy", "Bypass", "-EncodedCommand", encoded(command)], {
      windowsHide: true,
      timeout,
      maxBuffer: 4 * 1024 * 1024
    });
    return String(result.stdout || "").trim();
  } catch (error) {
    const detail = error instanceof Error ? error.message : String(error);
    throw new RuntimeError("desktop_command_failed", `桌面操作失败：${detail}`, { detail });
  }
}

export function psString(value: unknown): string {
  return `'${String(value ?? "").replace(/'/g, "''")}'`;
}

const keyboardSend: CapabilityHandler = async (_ctx, node, args) => {
  const keys = text(args, ["keys", "key", "text", "value"]);
  if (!keys) throw new RuntimeError("validation_error", "键盘输入为空", { nodeId: node.id, componentId: node.componentId });
  await powershell(`Add-Type -AssemblyName System.Windows.Forms; [System.Windows.Forms.SendKeys]::SendWait(${psString(keys)})`);
  return keys;
};

const mouseClick: CapabilityHandler = async (_ctx, node, args) => {
  const [x, y] = point(args.position ?? args.point ?? args.location ?? "[0,0]");
  const button = text(args, ["side", "button"], "0").toLowerCase();
  const down = button.includes("right") || button === "1" ? 0x0008 : 0x0002;
  const up = button.includes("right") || button === "1" ? 0x0010 : 0x0004;
  await powershell(`${USER32}; [RpaUser32]::SetCursorPos(${x},${y}); [RpaUser32]::mouse_event(${down},0,0,0,[UIntPtr]::Zero); [RpaUser32]::mouse_event(${up},0,0,0,[UIntPtr]::Zero)`);
  return { x, y };
};

const mouseMove: CapabilityHandler = async (_ctx, node, args) => {
  const [x, y] = point(args.position ?? args.point ?? args.location ?? "[0,0]");
  await powershell(`${USER32}; [RpaUser32]::SetCursorPos(${x},${y})`);
  return { x, y };
};

const mouseDrag: CapabilityHandler = async (_ctx, node, args) => {
  const [sx, sy] = point(args.Start ?? args.start ?? "[0,0]");
  const [ex, ey] = point(args.End ?? args.end ?? "[0,0]");
  await powershell(`${USER32}; [RpaUser32]::SetCursorPos(${sx},${sy}); [RpaUser32]::mouse_event(0x0002,0,0,0,[UIntPtr]::Zero); Start-Sleep -Milliseconds 80; [RpaUser32]::SetCursorPos(${ex},${ey}); Start-Sleep -Milliseconds 80; [RpaUser32]::mouse_event(0x0004,0,0,0,[UIntPtr]::Zero)`);
  return { start: [sx, sy], end: [ex, ey] };
};

const mouseRoll: CapabilityHandler = async (_ctx, node, args) => {
  const amount = number(args, ["RollNum", "rollNum", "amount"], 1) * 120;
  await powershell(`${USER32}; [RpaUser32]::mouse_event(0x0800,0,0,${amount},[UIntPtr]::Zero)`);
  return amount;
};

const setActiveWindow: CapabilityHandler = async (_ctx, node, args) => {
  const selector = text(args, ["match_title", "select_title", "title", "target_window", "window_title"]);
  if (!selector) throw new RuntimeError("validation_error", "窗口标题为空", { nodeId: node.id, componentId: node.componentId });
  const result = await powershell(`${USER32}; $p = Get-Process | Where-Object { $_.MainWindowTitle -and $_.MainWindowTitle -like ${psString(`*${selector}*`)} } | Select-Object -First 1; if (-not $p) { throw '找不到窗口' }; [RpaUser32]::SetForegroundWindow($p.MainWindowHandle); $p.MainWindowTitle`);
  return result;
};

const getActiveWindow: CapabilityHandler = async () => powershell(`${USER32}; $sb = New-Object System.Text.StringBuilder 512; [RpaUser32]::GetWindowText([RpaUser32]::GetForegroundWindow(),$sb,$sb.Capacity) | Out-Null; $sb.ToString()`);

const windowExists: CapabilityHandler = async (_ctx, node, args) => {
  const selector = text(args, ["match_title", "select_title", "title", "target_window", "window_title"]);
  if (!selector) throw new RuntimeError("validation_error", "窗口标题为空", { nodeId: node.id, componentId: node.componentId });
  return (await powershell(`$p = Get-Process | Where-Object { $_.MainWindowTitle -and $_.MainWindowTitle -like ${psString(`*${selector}*`)} } | Select-Object -First 1; [bool]$p`)).toLowerCase() === "true";
};

const closeWindow: CapabilityHandler = async (_ctx, node, args) => {
  const selector = text(args, ["window_obj", "title", "target_window", "window_title"]);
  if (!selector) throw new RuntimeError("validation_error", "窗口标题为空", { nodeId: node.id, componentId: node.componentId });
  return powershell(`$p = Get-Process | Where-Object { $_.MainWindowTitle -and $_.MainWindowTitle -like ${psString(`*${selector}*`)} } | Select-Object -First 1; if (-not $p) { throw '找不到窗口' }; $p.CloseMainWindow() | Out-Null; $true`);
};

const runApp: CapabilityHandler = async (_ctx, node, args) => {
  const executable = text(args, ["executeable", "executable", "path"]);
  if (!executable) throw new RuntimeError("validation_error", "应用路径为空", { nodeId: node.id, componentId: node.componentId });
  const params = text(args, ["params", "arguments"]);
  const cwd = text(args, ["cwd"]);
  const argPart = params ? ` -ArgumentList ${psString(params)}` : "";
  const result = await powershell(`$p = Start-Process -FilePath ${psString(executable)}${argPart} ${cwd ? `-WorkingDirectory ${psString(cwd)}` : ""} -PassThru; $p.Id`);
  return Number(result) || result;
};

const clipboardGet: CapabilityHandler = async () => powershell("Get-Clipboard -Raw");
const clipboardSet: CapabilityHandler = async (_ctx, _node, args) => {
  const content = text(args, ["text", "value"]);
  await powershell(`Set-Clipboard -Value ${psString(content)}`);
  return content;
};

const notice: CapabilityHandler = async (_ctx, _node, args) => {
  const title = text(args, ["title"], "提醒");
  const content = text(args, ["text", "message"]);
  await powershell(`Add-Type -AssemblyName System.Windows.Forms; [System.Windows.Forms.MessageBox]::Show(${psString(content)},${psString(title)}) | Out-Null`);
  return true;
};

const executeCommand: CapabilityHandler = async (_ctx, node, args) => {
  const command = text(args, ["action", "command"]);
  if (!command) throw new RuntimeError("validation_error", "命令行为空", { nodeId: node.id, componentId: node.componentId });
  return powershell(command, Math.max(1000, number(args, ["timeoutMs"], 120000)));
};

register("System_ExecuteCommandV1", async (ctx, node, args) => {
  const type = String(args.command_type ?? "1");
  const dos = String(args.dos_command ?? "").trim();
  const bat = String(args.bat_file ?? "").trim();
  const ps = String(args.ps_command ?? "").trim();
  let command = ps;
  if (type === "2") command = dos;
  else if (type === "3") command = bat ? ("& '" + bat.replace(/'/g, "''") + "'") : "";
  if (!command) {
    throw new RuntimeError("validation_error", "命令为空", { nodeId: node.id, componentId: node.componentId, recommendation: "填写 PowerShell/DOS 命令或 BAT 文件路径" });
  }
  return powershell(command, Math.max(1000, Number(args.timeoutMs) || 120000));
});

register(["Keyboard_Send_V1", "Keyboard_Send", "Keyboard_PressNew", "Keyboard_Press"], keyboardSend);
register(["Mouse_Click", "Mouse_ClickNew"], mouseClick);
register(["Mouse_MoveTo", "Mouse_Move"], mouseMove);
register(["Mouse_DragTo", "Mouse_Drag"], mouseDrag);
register(["Mouse_RollTo", "Mouse_Scroll"], mouseRoll);
register(["Window_SetActive", "Window_Activate"], setActiveWindow);
register(["Window_GetActive", "Window_GetActiveWindow"], getActiveWindow);
register(["Window_WindowExists", "Window_Exists"], windowExists);
register(["Window_CloseWindow", "Window_Close"], closeWindow);
register(["App_Run", "App_Start"], runApp);
register("Clipboard_GetText", clipboardGet);
register("Clipboard_SetText", clipboardSet);
register("Dialog_Notice", notice);
register("Dialog_MsgBox", notice);
register("System_ExecuteCommand", executeCommand);