import { NextResponse } from "next/server"
import { z } from "zod"
import bcrypt from "bcryptjs"
import { prisma } from "@/lib/prisma"
import { rateLimit } from "@/lib/rate-limit"

const registerSchema = z.object({
  name: z
    .string()
    .min(1, "Name is required")
    .max(100, "Name must be 100 characters or less"),
  email: z
    .string()
    .min(1, "Email is required")
    .email("Invalid email address"),
  password: z
    .string()
    .min(10, "Password must be at least 10 characters")
    .max(128, "Password must be 128 characters or less")
    .regex(/[a-z]/, "Password must contain at least one lowercase letter")
    .regex(/[A-Z]/, "Password must contain at least one uppercase letter")
    .regex(/[0-9]/, "Password must contain at least one number"),
})

export async function POST(request: Request) {
  try {
    // Rate limit: 5 registration attempts per IP per minute
    const forwarded = request.headers.get("x-forwarded-for")
    const ip = forwarded?.split(",")[0]?.trim() ?? "unknown"
    const rl = rateLimit(`register:${ip}`, 5, 60 * 1000)
    if (!rl.success) {
      return NextResponse.json(
        { error: "Too many registration attempts. Please try again later." },
        { status: 429 }
      )
    }

    const body = await request.json()
    const result = registerSchema.safeParse(body)

    if (!result.success) {
      const errors = result.error.flatten().fieldErrors
      return NextResponse.json(
        { error: "Validation failed", details: errors },
        { status: 400 }
      )
    }

    const { name, email, password } = result.data

    const existingUser = await prisma.user.findUnique({ where: { email } })
    if (existingUser) {
      return NextResponse.json(
        { error: "An account with this email already exists" },
        { status: 409 }
      )
    }

    const hashedPassword = await bcrypt.hash(password, 10)

    const user = await prisma.user.create({
      data: {
        name,
        email,
        password: hashedPassword,
        emailVerified: new Date(),
      },
    })

    return NextResponse.json(
      { id: user.id, name: user.name, email: user.email },
      { status: 201 }
    )
  } catch {
    return NextResponse.json(
      { error: "Something went wrong. Please try again." },
      { status: 500 }
    )
  }
}