/**
 * @fileoverview Manages the events page functionality.
 * This file handles event filtering, pagination, and modal interactions.
 */

document.addEventListener('DOMContentLoaded', function() {
    // Elements
    const eventTypeFilter = document.getElementById('eventTypeFilter');
    const dateRangeFilter = document.getElementById('dateRangeFilter');
    const userFilter = document.getElementById('userFilter');
    const applyFiltersBtn = document.getElementById('applyFilters');
    const eventsTableBody = document.getElementById('eventsTableBody');
    const prevPageBtn = document.getElementById('prevPage');
    const nextPageBtn = document.getElementById('nextPage');
    const currentPageSpan = document.getElementById('currentPage');
    const totalPagesSpan = document.getElementById('totalPages');
    const eventDetailsModal = document.getElementById('eventDetailsModal');
    const eventDetailsContent = document.getElementById('eventDetailsContent');

    // State
    let currentPage = 1;
    let totalPages = 1;
    let currentFilters = {
        eventType: '',
        dateRange: '24h',
        userId: ''
    };

    /**
     * Loads events based on current filters and page
     */
    async function loadEvents() {
        try {
            const response = await fetch(`/api/events?page=${currentPage}&${new URLSearchParams(currentFilters)}`);
            const data = await response.json();
            
            if (data.success) {
                renderEvents(data.events);
                updatePagination(data.total_pages);
            } else {
                console.error('Failed to load events:', data.error);
            }
        } catch (error) {
            console.error('Error loading events:', error);
        }
    }

    /**
     * Renders events in the table
     */
    function renderEvents(events) {
        if (!Array.isArray(events)) {
            console.error('Invalid events data received:', events);
            return;
        }

        const eventRows = events.map(event => {
            if (!event || typeof event !== 'object') {
                console.error('Invalid event data:', event);
                return '';
            }

            // Determine badge color and text based on event type
            let badgeClass = 'bg-secondary';
            let eventText = event.event_type || 'Unknown Event';
            
            switch(event.event_type) {
                case 'user_login':
                    badgeClass = 'bg-success';
                    eventText = 'User Login';
                    break;
                case 'user_logout':
                    badgeClass = 'bg-secondary';
                    eventText = 'User Logout';
                    break;
                case 'user_register':
                    badgeClass = 'bg-info';
                    eventText = 'User Registration';
                    break;
                case 'user_update':
                    badgeClass = 'bg-primary';
                    eventText = 'User Update';
                    break;
                case 'file_upload':
                    badgeClass = 'bg-success';
                    eventText = 'File Upload';
                    break;
                case 'file_delete':
                    badgeClass = 'bg-danger';
                    eventText = 'File Delete';
                    break;
                case 'file_download':
                    badgeClass = 'bg-info';
                    eventText = 'File Download';
                    break;
                case 'file_restore':
                    badgeClass = 'bg-warning';
                    eventText = 'File Restore';
                    break;
                case 'file_move':
                    badgeClass = 'bg-primary';
                    eventText = 'File Move';
                    break;
                case 'file_rename':
                    badgeClass = 'bg-info';
                    eventText = 'File Rename';
                    break;
                case 'file_star':
                    badgeClass = 'bg-warning';
                    eventText = 'File Star';
                    break;
                case 'file_unstar':
                    badgeClass = 'bg-secondary';
                    eventText = 'File Unstar';
                    break;
                case 'room_create':
                    badgeClass = 'bg-success';
                    eventText = 'Room Create';
                    break;
                case 'room_delete':
                    badgeClass = 'bg-danger';
                    eventText = 'Room Delete';
                    break;
                case 'room_update':
                    badgeClass = 'bg-primary';
                    eventText = 'Room Update';
                    break;
                case 'room_join':
                    badgeClass = 'bg-info';
                    eventText = 'Room Join';
                    break;
                case 'room_leave':
                    badgeClass = 'bg-secondary';
                    eventText = 'Room Leave';
                    break;
                case 'conversation_create':
                    badgeClass = 'bg-success';
                    eventText = 'Conversation Create';
                    break;
                case 'conversation_delete':
                    badgeClass = 'bg-danger';
                    eventText = 'Conversation Delete';
                    break;
                case 'message_sent':
                    badgeClass = 'bg-primary';
                    eventText = 'Message Sent';
                    break;
                case 'attachment_download':
                    badgeClass = 'bg-info';
                    eventText = 'Attachment Download';
                    break;
            }

            const timestamp = event.timestamp ? new Date(event.timestamp).toLocaleString() : '-';
            const username = event.user?.username || 'Unknown User';
            const lastName = event.user?.last_name || '';
            const eventId = event.id || '';
            const ipAddress = event.ip_address || '-';

            return `
                <tr>
                    <td>${timestamp}</td>
                    <td><span class="badge ${badgeClass}">${eventText}</span></td>
                    <td>${username} ${lastName}</td>
                    <td>
                        <button class="btn btn-sm btn-outline-secondary" 
                                data-bs-toggle="modal" 
                                data-bs-target="#eventDetailsModal"
                                data-event-id="${eventId}">
                            <i class="fas fa-info-circle"></i> View Details
                        </button>
                    </td>
                    <td>${ipAddress}</td>
                </tr>
            `;
        }).join('');

        eventsTableBody.innerHTML = eventRows;

        // Add event listeners to detail buttons
        document.querySelectorAll('[data-event-id]').forEach(button => {
            button.addEventListener('click', () => {
                const eventId = button.dataset.eventId;
                if (eventId) {
                    showEventDetails(eventId);
                }
            });
        });
    }

    /**
     * Updates pagination controls
     */
    function updatePagination(total) {
        totalPages = total;
        currentPageSpan.textContent = currentPage;
        totalPagesSpan.textContent = totalPages;
        
        prevPageBtn.classList.toggle('disabled', currentPage === 1);
        nextPageBtn.classList.toggle('disabled', currentPage === totalPages);
    }

    /**
     * Shows event details in modal
     */
    async function showEventDetails(eventId) {
        try {
            const response = await fetch(`/api/events/${eventId}`);
            const data = await response.json();
            
            if (data.success) {
                const event = data.event;
                eventDetailsContent.textContent = JSON.stringify(event.details, null, 2);
            } else {
                console.error('Failed to load event details:', data.error);
            }
        } catch (error) {
            console.error('Error loading event details:', error);
        }
    }

    /**
     * Loads users for the user filter
     */
    async function loadUsers() {
        try {
            const response = await fetch('/api/users');
            const data = await response.json();
            
            const userFilter = document.getElementById('userFilter');
            userFilter.innerHTML = '<option value="">All Users</option>';
            
            data.users.forEach(user => {
                const option = document.createElement('option');
                option.value = user.id;
                option.textContent = `${user.username} ${user.last_name || ''}`.trim();
                userFilter.appendChild(option);
            });
        } catch (error) {
            console.error('Error loading users:', error);
        }
    }

    // Event Listeners
    applyFiltersBtn.addEventListener('click', () => {
        currentFilters = {
            eventType: eventTypeFilter.value,
            dateRange: dateRangeFilter.value,
            userId: userFilter.value
        };
        currentPage = 1;
        loadEvents();
    });

    prevPageBtn.addEventListener('click', () => {
        if (currentPage > 1) {
            currentPage--;
            loadEvents();
        }
    });

    nextPageBtn.addEventListener('click', () => {
        if (currentPage < totalPages) {
            currentPage++;
            loadEvents();
        }
    });

    // Initialize
    loadUsers();
    loadEvents();
});