import type { Metadata } from "next";
import { CalendarPlus, Mail, Phone } from "lucide-react";
import Link from "next/link";
import { notFound, redirect } from "next/navigation";
import { Card } from "@/components/ui/card";
import { StatusPill } from "@/components/ui/status-pill";
import { TopNav } from "@/components/navigation/top-nav";
import { prisma } from "@/lib/db/prisma";
import { getActingStaff } from "@/lib/staff/get-acting-staff";
import { getLoyaltySummary } from "@/services/loyalty/loyalty.service";
import { getAppointmentById } from "@/services/scheduling/appointment.service";
import { assertOwnAppointment, StaffPermissionDeniedError } from "@/features/staff/authorization";
import { AppointmentStatusActions } from "@/features/staff/components/appointment-status-actions";
import { AddStampButton } from "@/features/staff/components/add-stamp-button";
import { BookFollowUpButton } from "@/features/staff/components/book-follow-up-button";
import { RedeemRewardButton } from "@/features/owner/components/redeem-reward-button";
import type { AppointmentStatus } from "@/types/domain";

export const metadata: Metadata = { title: "Appointment Details" };
export const dynamic = "force-dynamic";

const STATUS_MAP: Record<string, AppointmentStatus> = {
  PENDING: "pending_approval",
  CONFIRMED: "confirmed",
  CHECKED_IN: "arrived",
  IN_PROGRESS: "in_progress",
  COMPLETED: "completed",
  CANCELLED: "cancelled",
  NO_SHOW: "no_show",
};
const RESCHEDULABLE = new Set(["PENDING", "CONFIRMED", "CHECKED_IN"]);

export default async function StaffAppointmentDetailsPage({
  params,
}: {
  params: Promise<{ id: string }>;
}) {
  const staff = await getActingStaff();
  if (!staff) redirect("/home");

  const { id } = await params;
  const appointment = await getAppointmentById(prisma, id);
  if (!appointment) notFound();

  try {
    assertOwnAppointment(appointment, staff);
  } catch (error) {
    if (error instanceof StaffPermissionDeniedError) notFound();
    throw error;
  }

  const [notes, loyaltyTransactions, loyalty, cancelledByUser] = await Promise.all([
    prisma.customerNote.findMany({
      where: { customerId: appointment.customerId },
      orderBy: { createdAt: "desc" },
      take: 5,
      include: { author: { include: { user: { select: { name: true } } } } },
    }),
    prisma.loyaltyTransaction.findMany({
      where: { appointmentId: appointment.id },
      orderBy: { createdAt: "desc" },
    }),
    getLoyaltySummary(prisma, { customerId: appointment.customerId, businessId: staff.businessId }),
    appointment.cancelledByUserId
      ? prisma.user.findUnique({
          where: { id: appointment.cancelledByUserId },
          select: { name: true },
        })
      : null,
  ]);

  const tz = staff.business.timezone;
  const totalDuration = appointment.services.reduce(
    (sum, s) => sum + s.durationAtBookingMinutes,
    0,
  );
  const totalPrice = appointment.services.reduce((sum, s) => sum + Number(s.priceAtBooking), 0);
  const discount = appointment.discountAmount ? Number(appointment.discountAmount) : 0;
  const canRedeemReward =
    loyalty?.availableReward && appointment.discountAmount === null && appointment.status !== "CANCELLED";

  return (
    <div className="pb-12">
      <TopNav title="Appointment Details" onBack sticky className="bg-stone" />

      <main className="mx-auto max-w-2xl space-y-4 px-6 py-6">
        <Card className="space-y-6 p-6">
          <div className="flex items-center justify-between">
            <StatusPill status={STATUS_MAP[appointment.status] ?? "confirmed"} />
            <span className="text-muted text-[10px] font-bold tracking-widest uppercase">
              Ref: {appointment.id.slice(-8)}
            </span>
          </div>

          <div className="border-line space-y-1 border-t pt-4">
            <Link
              href={`/staff/clients/${appointment.customerId}`}
              className="text-lg font-bold underline"
            >
              {appointment.customer.firstName} {appointment.customer.lastName}
            </Link>
            <p className="text-muted text-sm">
              {appointment.customer.isGuest ? "Guest customer" : "Registered customer"}
            </p>
          </div>

          <div className="flex flex-wrap gap-3">
            {appointment.customer.phone && (
              <a
                href={`tel:${appointment.customer.phone}`}
                className="border-line flex items-center gap-2 rounded-lg border bg-white px-4 py-2 text-xs font-bold"
              >
                <Phone className="text-accent h-3.5 w-3.5" aria-hidden="true" /> Call
              </a>
            )}
            <a
              href={`mailto:${appointment.customer.email}`}
              className="border-line flex items-center gap-2 rounded-lg border bg-white px-4 py-2 text-xs font-bold"
            >
              <Mail className="text-accent h-3.5 w-3.5" aria-hidden="true" /> Email
            </a>
          </div>

          <div className="border-line grid grid-cols-2 gap-4 border-t pt-4 text-sm">
            <div>
              <span className="text-muted block text-[10px] font-bold tracking-widest uppercase">
                Services
              </span>
              <p className="font-bold">
                {appointment.services.map((s) => s.service.name).join(" + ")}
              </p>
            </div>
            <div>
              <span className="text-muted block text-[10px] font-bold tracking-widest uppercase">
                Date
              </span>
              <p className="font-bold">
                {appointment.startAt.toLocaleDateString("en-GB", {
                  weekday: "short",
                  day: "numeric",
                  month: "short",
                  timeZone: tz,
                })}
              </p>
            </div>
            <div>
              <span className="text-muted block text-[10px] font-bold tracking-widest uppercase">
                Time
              </span>
              <p className="font-bold">
                {appointment.startAt.toLocaleTimeString("en-GB", {
                  hour: "2-digit",
                  minute: "2-digit",
                  timeZone: tz,
                })}{" "}
                –{" "}
                {appointment.endAt.toLocaleTimeString("en-GB", {
                  hour: "2-digit",
                  minute: "2-digit",
                  timeZone: tz,
                })}
              </p>
            </div>
            <div>
              <span className="text-muted block text-[10px] font-bold tracking-widest uppercase">
                Duration / Price
              </span>
              <p className="font-bold">
                {totalDuration} min · £{totalPrice.toFixed(2)}
                {discount > 0 && (
                  <span className="text-accent-loyalty"> (-£{discount.toFixed(2)} reward)</span>
                )}
              </p>
            </div>
          </div>

          {appointment.notes && (
            <div className="border-line border-t pt-4">
              <span className="text-muted block text-[10px] font-bold tracking-widest uppercase">
                Booking Notes
              </span>
              <p className="text-muted mt-1 text-sm italic">{appointment.notes}</p>
            </div>
          )}

          {notes.length > 0 && (
            <div className="border-line border-t pt-4">
              <span className="text-muted block text-[10px] font-bold tracking-widest uppercase">
                Customer Notes
              </span>
              <div className="mt-2 space-y-2">
                {notes.map((n) => (
                  <p key={n.id} className="text-muted text-xs">
                    <span className="font-bold">{n.author.user.name ?? "Staff"}:</span> {n.body}
                  </p>
                ))}
              </div>
            </div>
          )}

          {loyalty?.isEnabled && (
            <div className="border-line border-t pt-4">
              <span className="text-muted block text-[10px] font-bold tracking-widest uppercase">
                Loyalty
              </span>
              <p className="text-sm font-bold">
                {loyalty.currentStamps}/{loyalty.stampsRequired} stamps
                {loyalty.availableReward && (
                  <span className="text-accent-loyalty"> · Reward available</span>
                )}
              </p>
              {loyaltyTransactions.length > 0 && (
                <ul className="mt-2 space-y-1">
                  {loyaltyTransactions.map((t) => (
                    <li key={t.id} className="text-muted text-xs">
                      {t.amount > 0 ? "+" : ""}
                      {t.amount} stamp{Math.abs(t.amount) === 1 ? "" : "s"} —{" "}
                      {t.type.replace("_", " ").toLowerCase()}
                      {t.reason ? ` (${t.reason})` : ""}
                    </li>
                  ))}
                </ul>
              )}
            </div>
          )}

          {appointment.status === "CANCELLED" && (
            <div className="border-line border-t pt-4 text-sm">
              <span className="text-muted block text-[10px] font-bold tracking-widest uppercase">
                Cancellation
              </span>
              <p className="text-muted mt-1">
                Cancelled {appointment.cancelledAt?.toLocaleString("en-GB", { timeZone: tz })}
                {cancelledByUser ? ` by ${cancelledByUser.name}` : ""}
              </p>
              {appointment.cancellationReason && (
                <p className="text-muted mt-1 italic">
                  &ldquo;{appointment.cancellationReason}&rdquo;
                </p>
              )}
            </div>
          )}
        </Card>

        <div className="flex flex-wrap gap-3">
          <a
            href={`/api/appointments/${appointment.id}/calendar.ics`}
            className="rounded-jumbo border-line flex items-center gap-2 border bg-white px-5 py-3 text-sm font-bold"
          >
            <CalendarPlus className="text-accent h-4 w-4" aria-hidden="true" /> Add to Calendar
          </a>
          {RESCHEDULABLE.has(appointment.status) && (
            <Link
              href={`/staff/appointments/${appointment.id}/reschedule`}
              className="rounded-jumbo border-line border bg-white px-5 py-3 text-sm font-bold"
            >
              Reschedule
            </Link>
          )}
          {appointment.status === "COMPLETED" && (
            <BookFollowUpButton appointmentId={appointment.id} />
          )}
        </div>

        <AppointmentStatusActions appointmentId={appointment.id} status={appointment.status} />

        <div className="flex flex-wrap gap-3">
          {loyalty?.isEnabled && (
            <AddStampButton customerId={appointment.customerId} appointmentId={appointment.id} />
          )}
          {canRedeemReward && loyalty?.availableReward && (
            <RedeemRewardButton
              appointmentId={appointment.id}
              rewardId={loyalty.availableReward.id}
              rewardLabel={loyalty.availableReward.label}
              subtotal={totalPrice}
            />
          )}
        </div>
      </main>
    </div>
  );
}