import { ChildProcess, spawn, SpawnOptions } from "child_process";
import { OpenCodeProcess } from "./OpenCodeProcess";

export class WindowsProcess implements OpenCodeProcess {
  start(
    command: string,
    args: string[],
    options: SpawnOptions
  ): ChildProcess {
    return spawn(command, args, {
      ...options,
      shell: true,
      windowsHide: true,
    });
  }

  async stop(process: ChildProcess): Promise<void> {
    const pid = process.pid;
    if (!pid) {
      return;
    }

    console.log("[OpenCode] Stopping server process tree, PID:", pid);

    // Use taskkill with /T flag to kill process tree
    await this.execAsync(`taskkill /T /F /PID ${pid}`);

    // Wait for process to exit
    await this.waitForExit(process, 5000);
  }

  async verifyCommand(command: string): Promise<string | null> {
    // Use 'where' command to check if executable exists in PATH
    try {
      await this.execAsync(`where "${command}"`);
      return null;
    } catch {
      return `Executable not found at '${command}'. Check Settings → OpenCode path, or click "Autodetect"`;
    }
  }

  private async waitForExit(
    process: ChildProcess,
    timeoutMs: number
  ): Promise<void> {
    if (process.exitCode !== null || process.signalCode !== null) {
      return; // Already exited
    }

    return new Promise((resolve) => {
      const timeout = setTimeout(() => {
        cleanup();
        resolve();
      }, timeoutMs);

      const onExit = () => {
        cleanup();
        resolve();
      };

      const cleanup = () => {
        clearTimeout(timeout);
        process.off("exit", onExit);
        process.off("error", onExit);
      };

      process.once("exit", onExit);
      process.once("error", onExit);
    });
  }

  private execAsync(command: string): Promise<void> {
    return new Promise((resolve, reject) => {
      const { exec } = require("child_process");
      exec(command, (error: Error | null) => {
        if (error) {
          reject(error);
        } else {
          resolve();
        }
      });
    });
  }
}