import { NextResponse } from 'next/server';

export async function POST(request: Request) {
  try {
    const { message } = await request.json();

    if (!message || typeof message !== 'string') {
      return NextResponse.json(
        { error: 'Message is required' },
        { status: 400 }
      );
    }

    // Call your n8n chat webhook
    const n8nWebhookUrl = process.env.N8N_WEBHOOK_URL;

    if (!n8nWebhookUrl) {
      console.error('N8N_WEBHOOK_URL not configured');
      // Return fallback response
      return NextResponse.json({
        reply: getFallbackResponse(message)
      });
    }

    const response = await fetch(`${n8nWebhookUrl}/webhook/chat`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        ...(process.env.N8N_API_KEY && {
          'Authorization': `Bearer ${process.env.N8N_API_KEY}`
        }),
      },
      body: JSON.stringify({ message }),
    });

    if (!response.ok) {
      throw new Error(`n8n webhook failed: ${response.status}`);
    }

    const data = await response.json();
    return NextResponse.json({ reply: data.reply || data.message || data.response });
  } catch (error) {
    console.error('Chat API error:', error);

    // Fallback to mock responses if n8n is down
    const { message } = await request.json();
    return NextResponse.json(
      { reply: getFallbackResponse(message) }
    );
  }
}

function getFallbackResponse(message: string): string {
  const lowerMessage = message.toLowerCase();

  if (lowerMessage.includes('skill') || lowerMessage.includes('tech')) {
    return "Dennis specializes in full-stack development with Next.js, Flutter for mobile, and DevOps with Docker Swarm. He's passionate about self-hosting and runs his own infrastructure!";
  }

  if (lowerMessage.includes('project')) {
    return "Dennis has built Clarity (a Flutter app for people with dyslexia) and runs a complete self-hosted infrastructure with Docker Swarm, Traefik, and automated CI/CD pipelines. Check out the Projects section for more!";
  }

  if (lowerMessage.includes('contact') || lowerMessage.includes('email') || lowerMessage.includes('reach')) {
    return "You can reach Dennis via the contact form on this site or email him at contact@dk0.dev. He's always open to discussing new opportunities and interesting projects!";
  }

  if (lowerMessage.includes('location') || lowerMessage.includes('where')) {
    return "Dennis is based in Osnabrück, Germany. He's a student who's passionate about technology and self-hosting.";
  }

  if (lowerMessage.includes('hobby') || lowerMessage.includes('free time')) {
    return "When Dennis isn't coding or managing servers, he enjoys gaming, jogging, and experimenting with new technologies. He also uses pen and paper for notes despite automating everything else!";
  }

  if (lowerMessage.includes('devops') || lowerMessage.includes('docker') || lowerMessage.includes('infrastructure')) {
    return "Dennis runs his own infrastructure on IONOS and OVHcloud using Docker Swarm, Traefik for reverse proxy, and custom CI/CD pipelines. He loves self-hosting and managing game servers!";
  }

  if (lowerMessage.includes('student') || lowerMessage.includes('study')) {
    return "Yes, Dennis is currently a student in Osnabrück while also working on various tech projects and managing his own infrastructure. He's always learning and exploring new technologies!";
  }

  // Default response
  return "That's a great question! Dennis is a full-stack developer and DevOps enthusiast who loves building things with Next.js, Flutter, and Docker. Feel free to ask me more specific questions about his skills, projects, or experience!";
}