import { NextRequest, NextResponse } from "next/server";
import { withPermission } from "@/lib/middleware/authorize";
import { withTenantContext } from "@/lib/prisma-tenant";
import { transitionTicketStatus } from "@/lib/services/ticket-service";
import { TicketStatus } from "@prisma/client";

/**
 * POST /api/tickets/[id]/status
 *
 * Transition a ticket to a new status.
 * Enforces the guard map: OPEN->ASSIGNED|CLOSED, ASSIGNED->OPEN|RESOLVED,
 * RESOLVED->CLOSED|OPEN, CLOSED->(terminal).
 *
 * Accepts: { status: TicketStatus }
 *
 * Requires: update on Ticket subject.
 *
 * Response:
 *   200 OK — updated ticket with new status
 *   400 Bad Request — invalid or disallowed transition
 *   404 Not Found — ticket not found
 *   401 Unauthorized — no session
 *   403 Forbidden — insufficient role
 */
export function POST(req: NextRequest, { params }: { params: Promise<{ id: string }> }) {
  return withPermission("update", "Ticket")(
    async (req: NextRequest, { user }) => {
      if (!user.tenantId) {
        return NextResponse.json(
          { error: "No tenant context — super-admins must use the admin API" },
          { status: 400 }
        );
      }

      const { id } = await params;

      let body: unknown;
      try {
        body = await req.json();
      } catch {
        return NextResponse.json({ error: "Invalid JSON body" }, { status: 400 });
      }

      const { status } = body as Record<string, unknown>;

      if (!status || typeof status !== "string") {
        return NextResponse.json({ error: "status is required" }, { status: 400 });
      }

      const validStatuses = Object.values(TicketStatus) as string[];
      if (!validStatuses.includes(status)) {
        return NextResponse.json(
          { error: `Invalid status. Must be one of: ${validStatuses.join(", ")}` },
          { status: 400 }
        );
      }

      const tenantPrisma = withTenantContext(user.tenantId);

      try {
        const ticket = await transitionTicketStatus(
          tenantPrisma,
          id,
          status as TicketStatus
        );
        return NextResponse.json(ticket);
      } catch (err) {
        const message = err instanceof Error ? err.message : "Failed to transition ticket status";
        if (message.includes("not found")) {
          return NextResponse.json({ error: message }, { status: 404 });
        }
        return NextResponse.json({ error: message }, { status: 400 });
      }
    }
  )(req);
}