import { NextResponse } from "next/server";
import { prisma } from "@/lib/prisma";
import { requireRole } from "@/lib/auth";
import { INVENTORY_CATEGORIES, INVENTORY_UNITS } from "@/lib/constants";

type Params = { params: Promise<{ id: string }> };

/** Update an inventory item's details. */
export async function PUT(req: Request, { params }: Params) {
  const session = await requireRole("INSTITUTION_ADMIN");
  if (!session || !session.institutionId) {
    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
  }
  const { id } = await params;

  try {
    const body = await req.json();
    const item = await prisma.inventoryItem.findFirst({
      where: { id: Number(id), institutionId: session.institutionId },
    });
    if (!item) return NextResponse.json({ error: "Not found" }, { status: 404 });

    const name = String(body.name ?? item.name).trim();
    if (!name) return NextResponse.json({ error: "Name required" }, { status: 400 });

    await prisma.inventoryItem.update({
      where: { id: item.id },
      data: {
        name,
        nameBn: body.nameBn !== undefined ? String(body.nameBn).trim() || null : item.nameBn,
        category: INVENTORY_CATEGORIES.includes(body.category as never) ? body.category : item.category,
        unit: INVENTORY_UNITS.includes(body.unit as never) ? body.unit : item.unit,
        minQuantity: body.minQuantity !== undefined ? Math.max(0, Number(body.minQuantity)) : item.minQuantity,
        unitPrice: body.unitPrice !== undefined ? Number(body.unitPrice) : item.unitPrice,
        location: body.location !== undefined ? String(body.location).trim() || null : item.location,
        note: body.note !== undefined ? String(body.note).trim() || null : item.note,
        isActive: body.isActive !== undefined ? Boolean(body.isActive) : item.isActive,
      },
    });
    return NextResponse.json({ success: true });
  } catch {
    return NextResponse.json({ error: "Could not update item" }, { status: 500 });
  }
}

/** Delete an inventory item (only when it has no movements). */
export async function DELETE(_req: Request, { params }: Params) {
  const session = await requireRole("INSTITUTION_ADMIN");
  if (!session || !session.institutionId) {
    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
  }
  const { id } = await params;

  const item = await prisma.inventoryItem.findFirst({
    where: { id: Number(id), institutionId: session.institutionId },
  });
  if (!item) return NextResponse.json({ error: "Not found" }, { status: 404 });

  const movements = await prisma.stockMovement.count({ where: { itemId: item.id } });
  if (movements > 0) return NextResponse.json({ error: "IN_USE" }, { status: 409 });

  await prisma.inventoryItem.delete({ where: { id: item.id } });
  return NextResponse.json({ success: true });
}