"use client";

import { useEffect, useState } from "react";
import Link from "next/link";
import type { PatientProfile } from "@duoc-thu/shared-types";
import { getPatientProfile, savePatientProfile } from "@duoc-thu/api-client";

const EMPTY: PatientProfile = {
  ageText: null,
  weightKg: null,
  renalFunction: null,
  hepaticFunction: null,
  knownAllergies: null,
};

/** Optional per-account clinical context. Nothing here is required — an
 * empty profile behaves exactly like no profile: the chatbot keeps asking
 * age/weight per turn, same as an anonymous session. Only a logged-in user
 * ever sees this page (`AccountMenu` is the only link to it). */
export function ProfileForm() {
  const [profile, setProfile] = useState<PatientProfile>(EMPTY);
  const [loaded, setLoaded] = useState(false);
  const [saved, setSaved] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const [pending, setPending] = useState(false);

  useEffect(() => {
    getPatientProfile()
      .then((p) => p && setProfile(p))
      .finally(() => setLoaded(true));
  }, []);

  async function onSubmit(event: React.FormEvent) {
    event.preventDefault();
    setError(null);
    setSaved(false);
    setPending(true);
    try {
      const result = await savePatientProfile(profile);
      setProfile(result);
      setSaved(true);
    } catch {
      setError("Không lưu được lúc này. Vui lòng thử lại.");
    } finally {
      setPending(false);
    }
  }

  if (!loaded) return null;

  return (
    <div className="flex flex-1 items-center justify-center p-6">
      <form
        onSubmit={onSubmit}
        className="w-full max-w-sm space-y-4 rounded-2xl border border-border-subtle bg-surface p-6 shadow-sm"
      >
        <div>
          <h1 className="text-lg font-bold text-txt-primary">
            Hồ sơ bệnh nhân
          </h1>
          <p className="mt-1 text-xs text-txt-secondary">
            Điền sẵn để không phải nhắc lại tuổi/cân nặng mỗi lượt hỏi. Bỏ
            trống mục nào thì chatbot vẫn hỏi lại mục đó như bình thường.
          </p>
        </div>

        <label className="block text-xs font-semibold text-txt-secondary">
          Tuổi
          <input
            type="text"
            value={profile.ageText ?? ""}
            onChange={(e) => setProfile({ ...profile, ageText: e.target.value })}
            placeholder="VD: 8 tuổi, sơ sinh 2 tháng"
            className="mt-1 w-full rounded-lg border border-border-subtle bg-surface-hover px-3 py-2 text-sm text-txt-primary"
          />
        </label>

        <label className="block text-xs font-semibold text-txt-secondary">
          Cân nặng (kg)
          <input
            type="number"
            min={0}
            max={500}
            value={profile.weightKg ?? ""}
            onChange={(e) =>
              setProfile({
                ...profile,
                weightKg: e.target.value === "" ? null : Number(e.target.value),
              })
            }
            className="mt-1 w-full rounded-lg border border-border-subtle bg-surface-hover px-3 py-2 text-sm text-txt-primary"
          />
        </label>

        <label className="block text-xs font-semibold text-txt-secondary">
          Chức năng thận
          <input
            type="text"
            value={profile.renalFunction ?? ""}
            onChange={(e) =>
              setProfile({ ...profile, renalFunction: e.target.value })
            }
            placeholder="VD: suy thận độ 2, Clcr 45 ml/phút"
            className="mt-1 w-full rounded-lg border border-border-subtle bg-surface-hover px-3 py-2 text-sm text-txt-primary"
          />
        </label>

        <label className="block text-xs font-semibold text-txt-secondary">
          Chức năng gan
          <input
            type="text"
            value={profile.hepaticFunction ?? ""}
            onChange={(e) =>
              setProfile({ ...profile, hepaticFunction: e.target.value })
            }
            placeholder="VD: suy gan nhẹ"
            className="mt-1 w-full rounded-lg border border-border-subtle bg-surface-hover px-3 py-2 text-sm text-txt-primary"
          />
        </label>

        <label className="block text-xs font-semibold text-txt-secondary">
          Dị ứng đã biết
          <input
            type="text"
            value={profile.knownAllergies ?? ""}
            onChange={(e) =>
              setProfile({ ...profile, knownAllergies: e.target.value })
            }
            placeholder="VD: dị ứng penicillin"
            className="mt-1 w-full rounded-lg border border-border-subtle bg-surface-hover px-3 py-2 text-sm text-txt-primary"
          />
        </label>

        {error && <p className="text-xs text-red-500">{error}</p>}
        {saved && !error && (
          <p className="text-xs text-emerald-600">Đã lưu.</p>
        )}

        <div className="flex items-center gap-3">
          <button
            type="submit"
            disabled={pending}
            className="rounded-lg bg-accent-primary px-4 py-2 text-sm font-semibold text-txt-inverse disabled:opacity-60"
          >
            {pending ? "Đang lưu..." : "Lưu"}
          </button>
          <Link href="/" className="text-xs text-txt-secondary hover:underline">
            Về trang tra cứu
          </Link>
        </div>
      </form>
    </div>
  );
}