Complete Developer Blueprint: WhatsApp Business API AI Integration

[ WhatsApp Business API ] ──(Webhook)──> [ Next.js Route Handler ] ──> [ Google Gemini 1.5 Flash ]
                                                      │
                                                      └──> [ CRM Database ]

// app/api/whatsapp/webhook/route.ts
import { NextResponse } from 'next/server';
import { GoogleGenerativeAI } from '@google/generative-ai';
const genAI = new GoogleGenerativeAI(process.env.GEMINI_API_KEY!);
export async function POST(req: Request) {
  const body = await req.json();
  const message = body.entry?.[0]?.changes?.[0]?.value?.messages?.[0];
  if (message && message.text) {
    const userText = message.text.body;
    const model = genAI.getGenerativeModel({ model: 'gemini-1.5-flash' });
    const result = await model.generateContent(userText);
    const aiReply = result.response.text();
    await sendWhatsAppMessage(message.from, aiReply);
  }
  return NextResponse.json({ status: 'ok' });
}