import { execSync, spawn } from "child_process";
import * as http from "http";
import { generateAutodocHtml } from "./autodoc";

function executeVoltageCommand(command: string): void {
  const cwd = process.cwd();

  try {
    // First try npx voltage
    execSync(`npx voltage ${command}`, {
      stdio: ['inherit', 'pipe', 'inherit'],
      cwd
    });
  } catch (error) {
    try {
      // Fallback to direct node_modules access
      execSync(`node node_modules/voltage-schema/dist/cli/index.js ${command}`, {
        stdio: ['inherit', 'pipe', 'inherit'],
        cwd
      });
    } catch (fallbackError) {
      throw new Error(`Failed to execute voltage command "${command}". Make sure voltage-schema is installed as a dependency.\nOriginal error: ${error}\nFallback error: ${fallbackError}`);
    }
  }
}

function openBrowser(url: string): void {
  const start = process.platform === 'darwin' ? 'open' :
                process.platform === 'win32' ? 'start' : 'xdg-open';
  spawn(start, [url], { detached: true, stdio: 'ignore' }).unref();
}

function startServer(html: string, port: number): void {
  const server = http.createServer((req, res) => {
    res.writeHead(200, { 'Content-Type': 'text/html' });
    res.end(html);
  });

  server.listen(port, 'localhost', () => {
    const url = `http://localhost:${port}`;
    console.log(`📚 Autodoc server started at ${url}`);
    console.log('🌐 Opening browser...');
    openBrowser(url);
    console.log('Press Ctrl+C to stop the server');
  });

  // Handle server shutdown gracefully
  process.on('SIGINT', () => {
    console.log('\n👋 Shutting down autodoc server...');
    server.close(() => {
      process.exit(0);
    });
  });
}

export class Command {
  private showHelp(): void {
    console.log(`
Usage: voltage-autodoc [options]

Options:
  --output-html    Output HTML documentation to stdout
  --port <number>  Port to serve the documentation (default: 5555)
  --help, -h       Show this help message

Examples:
  voltage-autodoc                    # Start server on http://localhost:5555
  voltage-autodoc --port 3000       # Start server on http://localhost:3000
  voltage-autodoc --output-html      # Output HTML to stdout
  voltage-autodoc --output-html > docs.html
`);
  }

    public parse(argv: string[]): void {
    const args = argv.slice(2);

    if (args.includes("--help") || args.includes("-h")) {
      this.showHelp();
      return;
    }

    // Parse port argument
    let port = 5555; // default port
    const portIndex = args.indexOf("--port");
    if (portIndex !== -1 && portIndex + 1 < args.length) {
      const portValue = parseInt(args[portIndex + 1], 10);
      if (isNaN(portValue) || portValue < 1 || portValue > 65535) {
        console.error("❌ Invalid port number. Please provide a port between 1 and 65535.");
        process.exit(1);
      }
      port = portValue;
    }

    try {
      console.log("🔍 Running validation via voltage-schema...");

      // Validate the schema first
      executeVoltageCommand("validate");

      console.log("📚 Generating autodoc HTML...");
      const html = generateAutodocHtml();

      if (args.includes("--output-html")) {
        // Output to stdout
        console.log(html);
      } else {
        // Start server
        startServer(html, port);
      }
    } catch (error) {
      console.error("❌ Error generating autodoc:", error);
      process.exit(1);
    }
  }
}