import React, { useState } from 'react';
import Modal from './Modal';
import Spinner from './common/Spinner';
import { login, register, forgotPassword } from '../client/auth-client';

const VIEW = {
  LOGIN: 'login',
  REGISTER: 'register',
  FORGOT_PASSWORD: 'forgot_password',
};

export default function AuthModal({ isOpen, setIsOpen, onAuthSuccess }) {
  const [view, setView] = useState(VIEW.LOGIN);
  const [isLoading, setIsLoading] = useState(false);
  const [error, setError] = useState('');

  const [loginUsername, setLoginUsername] = useState('');
  const [loginPassword, setLoginPassword] = useState('');

  const [registerUsername, setRegisterUsername] = useState('');
  const [registerEmail, setRegisterEmail] = useState('');
  const [registerPassword, setRegisterPassword] = useState('');
  const [registerConfirmPassword, setRegisterConfirmPassword] = useState('');

  const [forgotEmail, setForgotEmail] = useState('');
  const [successMessage, setSuccessMessage] = useState('');

  const resetForm = () => {
    setLoginUsername('');
    setLoginPassword('');
    setRegisterUsername('');
    setRegisterEmail('');
    setRegisterPassword('');
    setRegisterConfirmPassword('');
    setForgotEmail('');
    setError('');
    setSuccessMessage('');
  };

  const handleClose = () => {
    resetForm();
    setView(VIEW.LOGIN);
  };

  const switchView = newView => {
    resetForm();
    setView(newView);
  };

  const handleLogin = async e => {
    e.preventDefault();
    setError('');

    if (!loginUsername || !loginPassword) {
      setError('Please fill in all fields');
      return;
    }

    setIsLoading(true);
    const result = await login(loginUsername, loginPassword);
    setIsLoading(false);

    if (result.success) {
      resetForm();
      setIsOpen(false);
      if (onAuthSuccess) {
        onAuthSuccess(result.value);
      }
    } else {
      setError(result.error || 'Login failed');
    }
  };

  const handleRegister = async e => {
    e.preventDefault();
    setError('');

    if (!registerUsername || !registerEmail || !registerPassword || !registerConfirmPassword) {
      setError('Please fill in all fields');
      return;
    }

    if (registerPassword !== registerConfirmPassword) {
      setError('Passwords do not match');
      return;
    }

    if (registerPassword.length < 8) {
      setError('Password must be at least 8 characters');
      return;
    }

    setIsLoading(true);
    const result = await register(registerUsername, registerEmail, registerPassword);
    setIsLoading(false);

    if (result.success) {
      resetForm();
      setIsOpen(false);
      if (onAuthSuccess) {
        onAuthSuccess(result.value);
      }
    } else {
      setError(result.error || 'Registration failed');
    }
  };

  const handleForgotPassword = async e => {
    e.preventDefault();
    setError('');
    setSuccessMessage('');

    if (!forgotEmail) {
      setError('Please enter your email address');
      return;
    }

    setIsLoading(true);
    const result = await forgotPassword(forgotEmail);
    setIsLoading(false);

    if (result.success) {
      setSuccessMessage(result.value.message);
      setForgotEmail('');
    } else {
      setError(result.error || 'Failed to send reset email');
    }
  };

  return (
  <Modal
    isOpen={isOpen}
    setIsOpen={setIsOpen}
    onClose={handleClose}
    className='w-96 shadow shadow-primary rounded-md bg-primary-alt'
  >
    <Modal.Header className='text-center small-caps tracking-wide text-xl text-accent font-semibold'>
      {view === VIEW.LOGIN && 'Login'}
      {view === VIEW.REGISTER && 'Create Account'}
      {view === VIEW.FORGOT_PASSWORD && 'Reset Password'}
    </Modal.Header>

    <Modal.Body className='text-primary text-sm'>
      {view === VIEW.LOGIN && (
        <form onSubmit={handleLogin} className='m-4 flex flex-col gap-3'>
          <label htmlFor='login-username' className='flex flex-col gap-1'>
            <span className='text-secondary text-xs'>Username</span>
            <input
              id='login-username'
              name='username'
              type='text'
              className='input-primary text-sm form-input'
              placeholder='Enter username'
              value={loginUsername}
              onChange={e => setLoginUsername(e.target.value)}
              disabled={isLoading}
              autoComplete='username'
            />
          </label>

          <label htmlFor='login-password' className='flex flex-col gap-1'>
            <span className='text-secondary text-xs'>Password</span>
            <input
              id='login-password'
              name='password'
              type='password'
              className='input-primary text-sm form-input'
              placeholder='Enter password'
              value={loginPassword}
              onChange={e => setLoginPassword(e.target.value)}
              disabled={isLoading}
              autoComplete='current-password'
            />
          </label>

          {error && <div className='text-error text-xs text-center'>{error}</div>}

          <button type='submit' className='button-filled py-2 mt-2' disabled={isLoading}>
            {isLoading ? (
              <span className='flex items-center justify-center gap-2'>
                <Spinner size={Spinner.SIZE.sm} /> Logging in...
              </span>
            ) : (
              'Login'
            )}
          </button>

          <button
            type='button'
            className='text-accent text-xs hover:underline'
            onClick={() => switchView(VIEW.FORGOT_PASSWORD)}
          >
            Forgot password?
          </button>
        </form>
      )}

      {view === VIEW.REGISTER && (
        <form onSubmit={handleRegister} className='m-4 flex flex-col gap-3'>
          <label htmlFor='register-username' className='flex flex-col gap-1'>
            <span className='text-secondary text-xs'>Username</span>
            <input
              id='register-username'
              name='username'
              type='text'
              className='input-primary text-sm form-input'
              placeholder='Choose a username'
              value={registerUsername}
              onChange={e => setRegisterUsername(e.target.value)}
              disabled={isLoading}
              autoComplete='username'
            />
          </label>

          <label htmlFor='register-email' className='flex flex-col gap-1'>
            <span className='text-secondary text-xs'>Email</span>
            <input
              id='register-email'
              name='email'
              type='email'
              className='input-primary text-sm form-input'
              placeholder='Enter your email'
              value={registerEmail}
              onChange={e => setRegisterEmail(e.target.value)}
              disabled={isLoading}
              autoComplete='email'
            />
          </label>

          <label htmlFor='register-password' className='flex flex-col gap-1'>
            <span className='text-secondary text-xs'>Password</span>
            <input
              id='register-password'
              name='new-password'
              type='password'
              className='input-primary text-sm form-input'
              placeholder='Create a password'
              value={registerPassword}
              onChange={e => setRegisterPassword(e.target.value)}
              disabled={isLoading}
              autoComplete='new-password'
            />
          </label>

          <label htmlFor='register-confirm-password' className='flex flex-col gap-1'>
            <span className='text-secondary text-xs'>Confirm Password</span>
            <input
              id='register-confirm-password'
              name='confirm-password'
              type='password'
              className='input-primary text-sm form-input'
              placeholder='Confirm your password'
              value={registerConfirmPassword}
              onChange={e => setRegisterConfirmPassword(e.target.value)}
              disabled={isLoading}
              autoComplete='new-password'
            />
          </label>

          {error && <div className='text-error text-xs text-center'>{error}</div>}

          <button type='submit' className='button-filled py-2 mt-2' disabled={isLoading}>
            {isLoading ? (
              <span className='flex items-center justify-center gap-2'>
                <Spinner size={Spinner.SIZE.sm} /> Creating account...
              </span>
            ) : (
              'Create Account'
            )}
          </button>
        </form>
      )}

      {view === VIEW.FORGOT_PASSWORD && (
        <form onSubmit={handleForgotPassword} className='m-4 flex flex-col gap-3'>
          <p className='text-secondary text-xs'>
            Enter your email address and we&apos;ll send you a link to reset your password.
          </p>

          <label htmlFor='forgot-email' className='flex flex-col gap-1'>
            <span className='text-secondary text-xs'>Email</span>
            <input
              id='forgot-email'
              name='email'
              type='email'
              className='input-primary text-sm form-input'
              placeholder='Enter your email'
              value={forgotEmail}
              onChange={e => setForgotEmail(e.target.value)}
              disabled={isLoading}
              autoComplete='email'
            />
          </label>

          {error && <div className='text-error text-xs text-center'>{error}</div>}
          {successMessage && <div className='text-success text-xs text-center'>{successMessage}</div>}

          <button type='submit' className='button-filled py-2 mt-2' disabled={isLoading}>
            {isLoading ? (
              <span className='flex items-center justify-center gap-2'>
                <Spinner size={Spinner.SIZE.sm} /> Sending...
              </span>
            ) : (
              'Send Reset Link'
            )}
          </button>
        </form>
      )}
    </Modal.Body>

    <Modal.Footer className='text-center text-sm'>
      {view === VIEW.LOGIN && (
        <p className='text-secondary py-2'>
          Don&apos;t have an account?{' '}
          <button type='button' className='text-accent hover:underline' onClick={() => switchView(VIEW.REGISTER)}>
            Register
          </button>
        </p>
      )}
      {view === VIEW.REGISTER && (
        <p className='text-secondary py-2'>
          Already have an account?{' '}
          <button type='button' className='text-accent hover:underline' onClick={() => switchView(VIEW.LOGIN)}>
            Login
          </button>
        </p>
      )}
      {view === VIEW.FORGOT_PASSWORD && (
        <p className='text-secondary py-2'>
          Remember your password?{' '}
          <button type='button' className='text-accent hover:underline' onClick={() => switchView(VIEW.LOGIN)}>
            Login
          </button>
        </p>
      )}
    </Modal.Footer>
  </Modal>
);

}