import React, { useState, useEffect, useCallback } from 'react';
import { API, APIHandler, Validators } from './api.js';

const AlbumManager = () => {
    const [albums, setAlbums] = useState([]);
    const [loading, setLoading] = useState(true);
    const [error, setError] = useState(null);
    const [selectedAlbums, setSelectedAlbums] = useState(new Set());
    const [editingAlbum, setEditingAlbum] = useState(null);

    // Daten laden
    const fetchAlbums = useCallback(async () => {
        try {
            setLoading(true);
            const data = await APIHandler.get(API.albums.list);
            setAlbums(data);
            setError(null);
        } catch (err) {
            setError('Fehler beim Laden der Alben: ' + err.message);
            console.error('Fetch error:', err);
        } finally {
            setLoading(false);
        }
    }, []);

    useEffect(() => {
        fetchAlbums();
    }, [fetchAlbums]);


    // Album erstellen
    const handleCreate = async (name, description = '') => {
        try {
            //const validationErrors = Validators.album({ name });
            //if (Object.keys(validationErrors).length > 0) {
            //    throw new Error(Object.values(validationErrors).join(', '));
            //}

            await APIHandler.post(API.albums.create, { name, description });
            await fetchAlbums();
            window.showToast('Erfolg', 'Album wurde erstellt', 'success');
        } catch (err) {
            window.showToast('Fehler', err.message, 'danger');
        }
    };

    // Album aktualisieren
    const handleUpdate = async (id, updates) => {
        try {
            //const validationErrors = Validators.album(updates);
            //if (Object.keys(validationErrors).length > 0) {
            //    throw new Error(Object.values(validationErrors).join(', '));
            //}

            await APIHandler.put(API.albums.update(id), updates);
            await fetchAlbums();
            setEditingAlbum(null);
            window.showToast('Erfolg', 'Album wurde aktualisiert', 'success');
        } catch (err) {
            window.showToast('Fehler', err.message, 'danger');
        }
    };


    // Album aktualisieren
    const handleUpdate = async (id, updates) => {
        try {
            const validationErrors = Validators.album(updates);
            if (Object.keys(validationErrors).length > 0) {
                throw new Error(Object.values(validationErrors).join(', '));
            }

            await APIHandler.put(API.albums.update(id), updates);
            await fetchAlbums();
            setEditingAlbum(null);
            window.showToast('Erfolg', 'Album wurde aktualisiert', 'success');
        } catch (err) {
            window.showToast('Fehler', err.message, 'danger');
        }
    };

    // Massenbearbeitung
    const handleBulkDelete = async () => {
        if (selectedAlbums.size === 0) return;
        if (!window.confirm(`Möchten Sie ${selectedAlbums.size} Alben wirklich löschen?`)) return;

        try {
            await Promise.all(
                Array.from(selectedAlbums).map(id => 
                    APIHandler.delete(API.albums.delete(id))
                )
            );
            setSelectedAlbums(new Set());
            await fetchAlbums();
            window.showToast('Erfolg', 'Ausgewählte Alben wurden gelöscht', 'success');
        } catch (err) {
            window.showToast('Fehler', err.message, 'danger');
        }
    };

    const handleSelectAll = (event) => {
        if (event.target.checked) {
            setSelectedAlbums(new Set(albums.map(album => album.id)));
        } else {
            setSelectedAlbums(new Set());
        }
    };

    if (loading) {
        return (
            <div className="d-flex justify-content-center p-5">
                <div className="spinner-border text-primary" role="status">
                    <span className="visually-hidden">Laden...</span>
                </div>
            </div>
        );
    }

    if (error) {
        return (
            <div className="alert alert-danger m-3" role="alert">
                <h4 className="alert-heading">Fehler</h4>
                <p>{error}</p>
                <button 
                    className="btn btn-outline-danger"
                    onClick={fetchAlbums}
                >
                    Erneut versuchen
                </button>
            </div>
        );
    }

    return (
        <div className="card-body">
            {/* Toolbar */}
            <div className="d-flex justify-content-between mb-3">
                <button 
                    className="btn btn-primary"
                    onClick={() => setEditingAlbum({ name: '', description: '' })}
                >
                    <i className="bi bi-plus-lg"></i> Neues Album
                </button>
                {selectedAlbums.size > 0 && (
                    <button 
                        className="btn btn-danger"
                        onClick={handleBulkDelete}
                    >
                        <i className="bi bi-trash"></i> 
                        {selectedAlbums.size} Alben löschen
                    </button>
                )}
            </div>

            {/* Album Liste */}
            <div className="table-responsive">
                <table className="table table-hover">
                    <thead>
                        <tr>
                            <th>
                                <input 
                                    type="checkbox"
                                    className="form-check-input"
                                    onChange={handleSelectAll}
                                    checked={selectedAlbums.size === albums.length}
                                />
                            </th>
                            <th>Name</th>
                            <th>Bilder</th>
                            <th>Erstellt</th>
                            <th>Aktionen</th>
                        </tr>
                    </thead>
                    <tbody>
                        {albums.map(album => (
                            <tr key={album.id}>
                                <td>
                                    <input 
                                        type="checkbox"
                                        className="form-check-input"
                                        checked={selectedAlbums.has(album.id)}
                                        onChange={(e) => {
                                            const newSelected = new Set(selectedAlbums);
                                            if (e.target.checked) {
                                                newSelected.add(album.id);
                                            } else {
                                                newSelected.delete(album.id);
                                            }
                                            setSelectedAlbums(newSelected);
                                        }}
                                    />
                                </td>
                                <td>
                                    {editingAlbum?.id === album.id ? (
                                        <input 
                                            type="text"
                                            className="form-control"
                                            value={editingAlbum.name}
                                            onChange={(e) => setEditingAlbum({
                                                ...editingAlbum,
                                                name: e.target.value
                                            })}
                                        />
                                    ) : album.name}
                                </td>
                                <td>{album.imageCount}</td>
                                <td>{new Date(album.createdAt).toLocaleDateString()}</td>
                                <td>
                                    <div className="btn-group">
                                        {editingAlbum?.id === album.id ? (
                                            <>
                                                <button 
                                                    className="btn btn-sm btn-success"
                                                    onClick={() => handleUpdate(album.id, editingAlbum)}
                                                >
                                                    <i className="bi bi-check"></i>
                                                </button>
                                                <button 
                                                    className="btn btn-sm btn-secondary"
                                                    onClick={() => setEditingAlbum(null)}
                                                >
                                                    <i className="bi bi-x"></i>
                                                </button>
                                            </>
                                        ) : (
                                            <>
                                                <button 
                                                    className="btn btn-sm btn-outline-primary"
                                                    onClick={() => setEditingAlbum(album)}
                                                >
                                                    <i className="bi bi-pencil"></i>
                                                </button>
                                                <button 
                                                    className="btn btn-sm btn-outline-danger"
                                                    onClick={() => handleDelete(album.id)}
                                                >
                                                    <i className="bi bi-trash"></i>
                                                </button>
                                            </>
                                        )}
                                    </div>
                                </td>
                            </tr>
                        ))}
                    </tbody>
                </table>
            </div>

            {albums.length === 0 && (
                <div className="text-center text-muted p-5">
                    <i className="bi bi-folder-x display-4"></i>
                    <p className="mt-3">Keine Alben vorhanden</p>
                </div>
            )}
        </div>
    );
};

export default AlbumManager;
window.AlbumManager = AlbumManager; // <-- Diese Zeile ans Ende setzen