import React, { useEffect, useRef, useState } from 'react';
import { fetchIslandByUsername, uploadProfileAvatar } from '../../api/client';
import { useAuth } from '../../auth/AuthContext';
import '../../styles/profile.css';

/**
 * UserProfile: Modal showing user info with "Visit Island" button
 *
 * Props:
 * - username: string (required)
 * - onClose: function
 * - onVisitIsland: function(island) - called when "Visit Island" is clicked
 */
export default function UserProfile({ username, onClose, onVisitIsland }) {
  const { authenticated, username: authedUser, setAvatarUrl } = useAuth();
  const [island, setIsland] = useState(null);
  const [loading, setLoading] = useState(true);
  const [uploading, setUploading] = useState(false);
  const fileRef = useRef(null);

  const isSelf = authenticated && authedUser && authedUser.toLowerCase() === username.toLowerCase();

  useEffect(() => {
    if (!username) return;

    fetchIslandByUsername(username)
      .then(data => {
        setIsland(data);
        setLoading(false);
      })
      .catch(err => {
        console.error('[UserProfile] Error fetching island:', err);
        setLoading(false);
      });
  }, [username]);

  const handleVisitIsland = () => {
    if (island && onVisitIsland) {
      onVisitIsland(island);
    }
  };

  const handleChooseAvatar = () => {
    if (fileRef.current) fileRef.current.click();
  };

  const handleAvatarChange = async (e) => {
    const file = e.target.files && e.target.files[0];
    if (!file) return;
    setUploading(true);
    const res = await uploadProfileAvatar(file);
    if (res && res.ok && res.avatar_url) {
      setIsland(prev => (prev ? { ...prev, avatar_url: res.avatar_url } : prev));
      if (setAvatarUrl) setAvatarUrl(res.avatar_url);
    }
    setUploading(false);
  };

  return (
    <div className="user-profile-modal" onClick={onClose}>
      <div className="user-profile-container" onClick={(e) => e.stopPropagation()}>
        <button className="user-profile-close" onClick={onClose}>×</button>

        <div className="user-profile-header">
          <div className="user-profile-avatar">
            {island?.avatar_url ? (
              <img src={island.avatar_url} alt={username} />
            ) : (
              <div className="user-profile-avatar-letter">
                {username[0].toUpperCase()}
              </div>
            )}
          </div>
          <h2 className="user-profile-username">@{username}</h2>
          {island?.display_name && island.display_name !== `${username}'s Island` && (
            <p className="user-profile-display-name">{island.display_name}</p>
          )}
          {isSelf ? (
            <div className="user-profile-avatar-actions">
              <button
                className="user-profile-btn user-profile-btn-ghost"
                type="button"
                disabled={uploading}
                onClick={handleChooseAvatar}
              >
                {uploading ? 'Uploading...' : 'Change photo'}
              </button>
              <input
                ref={fileRef}
                type="file"
                accept="image/*"
                style={{ display: 'none' }}
                onChange={handleAvatarChange}
              />
            </div>
          ) : null}
        </div>

        {loading ? (
          <div className="user-profile-loading">Loading profile...</div>
        ) : island ? (
          <>
            <div className="user-profile-bio">
              <p>{island.bio || 'No bio yet.'}</p>
            </div>

            <div className="user-profile-stats">
              <div className="user-profile-stat">
                <span className="user-profile-stat-value">{island.content_count || 0}</span>
                <span className="user-profile-stat-label">Posts</span>
              </div>
              <div className="user-profile-stat">
                <span className="user-profile-stat-value">{island.visitors || 0}</span>
                <span className="user-profile-stat-label">Visitors</span>
              </div>
              <div className="user-profile-stat">
                <span className="user-profile-stat-value">{island.terrain_type || 'tropical'}</span>
                <span className="user-profile-stat-label">Terrain</span>
              </div>
            </div>

            <div className="user-profile-actions">
              <button
                className="user-profile-btn user-profile-btn-primary"
                onClick={handleVisitIsland}
              >
                🏝️ Visit Island
              </button>
            </div>

            <div className="user-profile-footer">
              <p className="user-profile-seed">Seed: {island.seed}</p>
            </div>
          </>
        ) : (
          <div className="user-profile-no-island">
            <p>This user doesn't have an island yet.</p>
          </div>
        )}
      </div>
    </div>
  );
}