import { useState, useCallback } from 'react';
import { useNavigate } from 'react-router-dom';
import { sajuInterpret } from '../../../api';

const INITIAL_FORM = {
  name: '',
  year: '',
  month: '',
  day: '',
  hour: '',
  gender: 'male',
  calendar_type: 'solar',
};

export default function useSajuForm() {
  const [form, setForm] = useState(INITIAL_FORM);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState(null);
  const navigate = useNavigate();

  const handleChange = useCallback((field, value) => {
    setForm((prev) => ({ ...prev, [field]: value }));
  }, []);

  const handleSubmit = useCallback(async (e) => {
    if (e?.preventDefault) e.preventDefault();
    setError(null);

    if (!form.year || !form.month || !form.day) {
      setError('생년월일을 모두 입력해주세요.');
      return;
    }
    const year = parseInt(form.year, 10);
    const month = parseInt(form.month, 10);
    const day = parseInt(form.day, 10);
    if (year < 1900 || year > 2100 || month < 1 || month > 12 || day < 1 || day > 31) {
      setError('올바른 생년월일을 입력해주세요.');
      return;
    }

    setLoading(true);
    try {
      const body = {
        year,
        month,
        day,
        gender: form.gender,
        calendar_type: form.calendar_type,
      };
      if (form.hour !== '') {
        body.hour = parseInt(form.hour, 10);
      }
      const result = await sajuInterpret(body);
      navigate(`/saju/result?rid=${result.reading_id}`);
    } catch (err) {
      console.error('사주 분석 실패', err);
      setError(err.message || '잠시 후 다시 시도해주세요.');
    } finally {
      setLoading(false);
    }
  }, [form, navigate]);

  return { form, handleChange, handleSubmit, loading, error };
}