// src/components/AuthModal.jsx
import { useState, useEffect } from "react";
import { useTranslation } from 'react-i18next';
import CloseIcon from "./icons/CloseIcon";
import { useAuthContext } from "../context/AuthContext";
import { login as apiLogin, register as apiRegister } from "../api/apiClient";

/**
 * AuthModal — модальное окно входа и регистрации прямо на странице ленты.
 * Открывается когда неавторизованный пользователь пытается создать объявление.
 */
export default function AuthModal({ onClose }) {
  const { t } = useTranslation();
  const [mode, setMode] = useState("login"); // "login" | "register"
  const { login: saveAuth } = useAuthContext();

  useEffect(() => {
    const prev = document.body.style.overflow;
    document.body.style.overflow = "hidden";
    return () => { document.body.style.overflow = prev; };
  }, []);

  return (
      <div className="f-modal-bg auth-modal-bg" onClick={e => e.target === e.currentTarget && onClose()}>
        <div className="f-modal auth-modal">
          <div className="f-modal-head">
          <span className="f-modal-title">
            {mode === "login" ? t('auth.loginModalTitle') : t('auth.registerModalTitle')}
          </span>
            <button className="f-close-btn" type="button" onClick={onClose}>
              <CloseIcon />
            </button>
          </div>

          {mode === "login"
              ? <LoginFormInline
                  saveAuth={saveAuth}
                  onClose={onClose}
                  onSwitch={() => setMode("register")}
              />
              : <RegisterFormInline
                  saveAuth={saveAuth}
                  onClose={onClose}
                  onSwitch={() => setMode("login")}
              />
          }
        </div>
      </div>
  );
}

// ─── Login form (inline modal) ──────────────────────────────────────────────
function LoginFormInline({ saveAuth, onClose, onSwitch }) {
  const { t } = useTranslation();
  const [login, setLogin]       = useState("");
  const [password, setPassword] = useState("");
  const [loading, setLoading]   = useState(false);
  const [error, setError]       = useState("");

  const handleSubmit = async (e) => {
    e.preventDefault();
    if (!login || !password) { setError(t('auth.enterLoginPassword')); return; }
    setLoading(true); setError("");

    try {
      const { token, refreshToken, user } = await apiLogin(
          login, password, t('auth.invalidCredentials')
      );
      saveAuth(user, token, refreshToken);
      onClose();
    } catch (err) {
      setError(err.message);
    } finally {
      setLoading(false);
    }
  };

  return (
      <form onSubmit={handleSubmit}>
        <div className="f-m-group">
          <label className="f-m-label">{t('auth.loginLabel')}</label>
          <input
              className="f-m-field"
              type="text"
              placeholder={t('auth.yourLogin')}
              value={login}
              onChange={e => { setLogin(e.target.value); setError(""); }}
              autoComplete="off"
          />
        </div>

        <div className="f-m-group">
          <label className="f-m-label">{t('auth.passwordLabel')}</label>
          <input
              className="f-m-field"
              type="password"
              placeholder={t('auth.yourPassword')}
              value={password}
              onChange={e => { setPassword(e.target.value); setError(""); }}
          />
        </div>

        {error && <p className="f-err-msg auth-form-error">{error}</p>}

        <SubmitButton loading={loading} label={t('auth.login')} />

        <p style={{textAlign: "center", marginTop: 14, color: "var(--muted)", fontSize: ".85rem"}}>
          {t('auth.noAccount')}{" "}
          <button type="button" onClick={onSwitch}
              style={{background: "none", border: "none", color: "var(--teal)", cursor: "pointer", fontWeight: 700, fontSize: ".85rem", fontFamily: "var(--font)",}}
          >
            {t('auth.register')}
          </button>
        </p>
      </form>
  );
}

// ─── Register form (inline modal) ──────────────────────────────────────────
function RegisterFormInline({ saveAuth, onClose, onSwitch }) {
  const { t } = useTranslation();
  const [form, setForm] = useState({
    name: "", login: "", password: "", password2: "",
  });
  const [loading, setLoading] = useState(false);
  const [error, setError]     = useState("");
  const [errors, setErrors]   = useState({});

  const setField = (key, val) => {
    setForm(p => ({ ...p, [key]: val }));
    setErrors(p => ({ ...p, [key]: "" }));
  };

  const validate = () => {
    const e = {};
    if (!form.name.trim())                e.name      = t('auth.validateNameRequired');
    if (!form.login.trim())               e.login     = t('auth.validateLoginRequired');
    else if (form.login.length < 3)       e.login     = t('auth.loginMinChars');
    if (form.password.length < 6)         e.password  = t('auth.validatePasswordMin');
    if (form.password !== form.password2) e.password2 = t('auth.validatePasswordMatch');
    setErrors(e);
    return !Object.keys(e).length;
  };

  const handleSubmit = async (e) => {
    e.preventDefault();
    if (!validate()) return;
    setLoading(true); setError("");

    try {
      await apiRegister(form.name, form.login, form.password, t('auth.registrationError'));

      let session;
      try {
        session = await apiLogin(form.login, form.password, t('auth.autoLoginFailed'));
      } catch {
        throw new Error(t('auth.accountCreatedLoginManually'));
      }

      const { token, refreshToken, user } = session;
      saveAuth(user, token, refreshToken);
      onClose();
    } catch (err) {
      setError(err.message);
    } finally {
      setLoading(false);
    }
  };

  return (
      <form onSubmit={handleSubmit}>
        <div className="f-m-group">
          <label className="f-m-label">{t('auth.nameLabel')}</label>
          <input
              className={`f-m-field${errors.name ? " err" : ""}`}
              type="text"
              placeholder={t('auth.namePlaceholder')}
              value={form.name}
              onChange={e => setField("name", e.target.value)}
          />
          {errors.name && <p className="f-err-msg">{errors.name}</p>}
        </div>

        <div className="f-m-group">
          <label className="f-m-label">{t('auth.loginLabel')}</label>
          <input
              className={`f-m-field${errors.login ? " err" : ""}`}
              type="text"
              placeholder={t('auth.loginPlaceholder')}
              value={form.login}
              onChange={e => setField("login", e.target.value)}
          />
          {errors.login && <p className="f-err-msg">{errors.login}</p>}
        </div>

        <div className="f-m-row">
          <div className="f-m-group">
            <label className="f-m-label">{t('auth.passwordLabel')}</label>
            <input
                className={`f-m-field${errors.password ? " err" : ""}`}
                type="password"
                placeholder={t('auth.passwordMinShort')}
                value={form.password}
                onChange={e => setField("password", e.target.value)}
            />
            {errors.password && <p className="f-err-msg">{errors.password}</p>}
          </div>
          <div className="f-m-group">
            <label className="f-m-label">{t('auth.repeatLabel')}</label>
            <input
                className={`f-m-field${errors.password2 ? " err" : ""}`}
                type="password"
                placeholder={t('auth.repeatPlaceholder')}
                value={form.password2}
                onChange={e => setField("password2", e.target.value)}
            />
            {errors.password2 && <p className="f-err-msg">{errors.password2}</p>}
          </div>
        </div>

        {error && <p className="f-err-msg auth-form-error">{error}</p>}

        <SubmitButton loading={loading} label={t('auth.createAccountBtn')} />

        <p style={{textAlign: "center", marginTop: 14, color: "var(--muted)", fontSize: ".85rem"}}>
          {t('auth.hasAccount')}{" "}
          <button type="button" onClick={onSwitch}
              style={{background: "none", border: "none", color: "var(--teal)", cursor: "pointer", fontWeight: 700, fontSize: ".85rem", fontFamily: "var(--font)",}}>
            {t('auth.loginLink')}
          </button>
        </p>
      </form>
  );
}

// ─── Shared submit button ──────────────────────────────────────────────────
function SubmitButton({ loading, label }) {
  return (
      <button className="f-m-submit auth-submit-btn" type="submit" disabled={loading}>
        <div className="f-m-submit-row">
          {loading && <div className="f-m-spinner" />}
          {label}
        </div>
      </button>
  );
}