import { type NextRequest } from "next/server";
import { prisma } from "@/lib/prisma";
import { ok, errorResponse, requireRole, parseJson, ApiError } from "@/lib/api";
import { CreateFastenerSchema } from "@/lib/schemas";
import { audit } from "@/lib/audit";
import { clientIp } from "@/lib/request";

/**
 * List fasteners on a project + compute "remaining to order" per row so the
 * PO draft UI can suggest line qtys. remaining = qty - sum(receivedQty on
 * open lines). Closed / cancelled PO lines don't count against the need.
 */
export async function GET(_req: NextRequest, ctx: { params: Promise<{ id: string }> }) {
  try {
    await requireRole("admin");
    const { id } = await ctx.params;

    const project = await prisma.project.findUnique({ where: { id }, select: { id: true } });
    if (!project) throw new ApiError(404, "not_found", "Project not found");

    const fasteners = await prisma.fastener.findMany({
      where: { projectId: id },
      orderBy: [{ supplier: "asc" }, { partNumber: "asc" }],
      include: {
        poLines: {
          select: {
            qty: true,
            receivedQty: true,
            po: { select: { status: true } },
          },
        },
      },
    });

    const rows = fasteners.map((f) => {
      let onOrder = 0;
      let received = 0;
      for (const line of f.poLines) {
        if (line.po.status === "cancelled") continue;
        onOrder += line.qty;
        received += line.receivedQty;
      }
      const remaining = Math.max(0, f.qty - received);
      const unresolved = Math.max(0, f.qty - onOrder);
      return {
        ...f,
        poLines: undefined,
        onOrder,
        received,
        remaining,
        unresolved, // qty we haven't put on any PO yet
      };
    });

    return ok({ fasteners: rows });
  } catch (err) {
    return errorResponse(err);
  }
}

export async function POST(req: NextRequest, ctx: { params: Promise<{ id: string }> }) {
  try {
    const actor = await requireRole("admin");
    const { id } = await ctx.params;
    const body = await parseJson(req, CreateFastenerSchema);

    const project = await prisma.project.findUnique({ where: { id }, select: { id: true } });
    if (!project) throw new ApiError(404, "not_found", "Project not found");

    const created = await prisma.fastener.create({
      data: {
        projectId: id,
        partNumber: body.partNumber,
        description: body.description,
        qty: body.qty,
        supplier: body.supplier ?? null,
        unitCost: body.unitCost ?? null,
        notes: body.notes ?? null,
      },
    });

    await audit({
      actorId: actor.id,
      action: "create",
      entity: "Fastener",
      entityId: created.id,
      after: created,
      ipAddress: clientIp(req),
    });

    return ok({ fastener: created }, { status: 201 });
  } catch (err) {
    return errorResponse(err);
  }
}