import { headers } from "next/headers";
import { auth } from "@/lib/auth/server";
import { db, mealPlans, eq, and } from "@epicure/db";
import { PrintTrigger } from "@/components/recipe/print-trigger";
import { getMessages, formatMessage } from "@/lib/i18n/server";

const DAYS = ["mon", "tue", "wed", "thu", "fri", "sat", "sun"] as const;
const MEAL_ORDER = ["breakfast", "lunch", "dinner", "snack"] as const;

function getMonday(dateStr?: string): Date {
  // Parse y/m/d directly into local time — new Date("YYYY-MM-DD") parses as
  // UTC midnight, which getDay() (local time) can read as the wrong weekday
  // depending on the server's timezone offset.
  const d = dateStr
    ? (() => {
        const [y, m, day] = dateStr.split("-").map(Number);
        return new Date(y!, m! - 1, day!);
      })()
    : new Date();
  const dow = d.getDay();
  const diff = dow === 0 ? -6 : 1 - dow;
  d.setDate(d.getDate() + diff);
  d.setHours(0, 0, 0, 0);
  return d;
}

function toDateStr(d: Date): string {
  const y = d.getFullYear();
  const m = String(d.getMonth() + 1).padStart(2, "0");
  const day = String(d.getDate()).padStart(2, "0");
  return `${y}-${m}-${day}`;
}

export default async function MealPlanPrintPage({
  searchParams,
}: {
  searchParams: Promise<{ week?: string }>;
}) {
  const { week } = await searchParams;
  const session = await auth.api.getSession({ headers: await headers() });
  if (!session) return null;

  const m = getMessages((session.user as { locale?: string }).locale);

  const monday = getMonday(week);
  const weekStart = toDateStr(monday);
  const sunday = new Date(monday);
  sunday.setDate(sunday.getDate() + 6);

  const plan = await db.query.mealPlans.findFirst({
    where: and(eq(mealPlans.userId, session.user.id), eq(mealPlans.weekStart, weekStart)),
    with: { entries: { with: { recipe: true } } },
  });

  const label = `${monday.toLocaleDateString("en-US", { month: "short", day: "numeric" })} – ${sunday.toLocaleDateString("en-US", { month: "short", day: "numeric", year: "numeric" })}`;

  const entries = plan?.entries ?? [];

  return (
    <>
      <style>{`
        @media print {
          body { margin: 0; }
          .no-print { display: none !important; }
        }
        body {
          font-family: system-ui, sans-serif;
          color: #1a1a1a;
          max-width: 900px;
          margin: 40px auto;
          padding: 0 24px;
          font-size: 13px;
          line-height: 1.5;
        }
        h1 { font-size: 1.8em; margin: 0 0 2px; }
        .subtitle { color: #666; font-size: 0.9em; margin-bottom: 24px; }
        table { width: 100%; border-collapse: collapse; table-layout: fixed; }
        th { text-align: left; font-size: 0.8em; text-transform: uppercase; letter-spacing: 0.06em; color: #888; padding: 6px 8px; border-bottom: 2px solid #ccc; }
        td { padding: 6px 8px; border-bottom: 1px solid #eee; border-right: 1px solid #eee; vertical-align: top; min-height: 40px; }
        td:last-child { border-right: none; }
        .meal-label { font-size: 0.75em; text-transform: uppercase; letter-spacing: 0.05em; color: #aaa; display: block; margin-bottom: 2px; }
        .recipe-title { font-weight: 500; }
        .servings { font-size: 0.8em; color: #888; }
        .empty { color: #ccc; font-size: 0.85em; }
        footer { margin-top: 40px; font-size: 0.75em; color: #aaa; text-align: center; }
        .print-btn {
          position: fixed; top: 16px; right: 16px; padding: 8px 16px;
          background: #18181b; color: white; border: none; border-radius: 6px;
          cursor: pointer; font-size: 13px;
        }
        .print-btn:hover { background: #3f3f46; }
      `}</style>

      <PrintTrigger />

      <h1>{m.mealPlan.title}</h1>
      <p className="subtitle">{label}</p>

      <table>
        <thead>
          <tr>
            <th style={{ width: "100px" }}>{m.print.day}</th>
            {MEAL_ORDER.map((meal) => (
              <th key={meal}>{m.mealPlan.meals[meal]}</th>
            ))}
          </tr>
        </thead>
        <tbody>
          {DAYS.map((day) => (
            <tr key={day}>
              <td style={{ fontWeight: 600, color: "#555" }}>{m.print.days[day]}</td>
              {MEAL_ORDER.map((mealType) => {
                const entry = entries.find((e) => e.day === day && e.mealType === mealType);
                return (
                  <td key={mealType}>
                    {entry ? (
                      <>
                        <span className="recipe-title">{entry.recipe?.title ?? entry.note ?? "—"}</span>
                        {entry.servings && (
                          <span className="servings">{formatMessage(m.print.srv, { count: entry.servings })}</span>
                        )}
                      </>
                    ) : (
                      <span className="empty">—</span>
                    )}
                  </td>
                );
              })}
            </tr>
          ))}
        </tbody>
      </table>

      <footer>{m.print.footer}</footer>
    </>
  );
}