import { NextRequest, NextResponse } from "next/server";
import { prisma } from "@/lib/db";

export async function PATCH(req: NextRequest, { params }: { params: Promise<{ id: string }> }) {
  try {
    const { id } = await params;
    const body = await req.json() as Record<string, unknown>;

    const oldLead = await prisma.lead.findUnique({ where: { id } });
    if (!oldLead) return NextResponse.json({ error: "Not found" }, { status: 404 });

    const allowedFields = [
      "status", "priority", "notes", "tags", "country", "headcount",
      "industry", "contactedAt", "companyName", "contactName", "contactTitle",
      "email", "phone", "linkedinUrl", "domain",
    ];

    const data: Record<string, unknown> = {};
    for (const field of allowedFields) {
      if (field in body) data[field] = body[field];
    }

    const updated = await prisma.lead.update({ where: { id }, data });

    // Track status change events
    if (body.status && body.status !== oldLead.status) {
      await prisma.leadEvent.create({
        data: {
          leadId: id,
          event: `Status geändert zu "${body.status}"`,
        },
      });

      // Auto-set contactedAt when marking as contacted
      if (body.status === "contacted" && !oldLead.contactedAt) {
        await prisma.lead.update({ where: { id }, data: { contactedAt: new Date() } });
      }
    }

    return NextResponse.json(updated);
  } catch (err) {
    console.error("PATCH /api/leads/[id] error:", err);
    return NextResponse.json({ error: "Update failed" }, { status: 500 });
  }
}

export async function DELETE(_req: NextRequest, { params }: { params: Promise<{ id: string }> }) {
  try {
    const { id } = await params;
    await prisma.lead.delete({ where: { id } });
    return NextResponse.json({ deleted: true });
  } catch (err) {
    console.error("DELETE /api/leads/[id] error:", err);
    return NextResponse.json({ error: "Delete failed" }, { status: 500 });
  }
}

export async function GET(_req: NextRequest, { params }: { params: Promise<{ id: string }> }) {
  try {
    const { id } = await params;
    const lead = await prisma.lead.findUnique({
      where: { id },
      include: { events: { orderBy: { at: "asc" } } },
    });
    if (!lead) return NextResponse.json({ error: "Not found" }, { status: 404 });
    return NextResponse.json(lead);
  } catch (err) {
    return NextResponse.json({ error: "Fetch failed" }, { status: 500 });
  }
}