// Fetch and display feeds
async function fetchFeeds() {
    try {
        const response = await fetch('/feeds');
        if (response.ok) {
            const feeds = await response.json();
            return feeds;
        } else {
            console.error('Failed to load feeds:', response.status);
            return null;
        }
    } catch (error) {
        console.error('Error loading feeds:', error);
        return null;
    }
}

// Close any open feed menus
function closeAllFeedMenus() {
    document.querySelectorAll('.feed-menu.show').forEach(menu => {
        menu.classList.remove('show');
    });
}

// Add click handler to close menus when clicking outside
document.addEventListener('click', (e) => {
    if (!e.target.closest('.feed-menu') && !e.target.closest('.feed-menu-button')) {
        closeAllFeedMenus();
    }
});

function formatDate(dateStr) {
    if (!dateStr) return 'Not available';
    const date = new Date(dateStr);
    return date.toLocaleString();
}

function renderFeedEntries(entries) {
    const mainContent = document.querySelector('.main-content');
    mainContent.innerHTML = '';

    entries.forEach(entry => {
        const entryDiv = document.createElement('div');
        entryDiv.className = 'feed-entry';

        const title = document.createElement('h2');
        title.className = 'feed-entry-title';

        const readToggle = document.createElement('button');
        readToggle.className = 'read-toggle';
        readToggle.title = entry.marked_read ? 'Mark as unread' : 'Mark as read';
        readToggle.innerHTML = entry.marked_read 
            ? '<i class="fa-solid fa-square-check"></i>'
            : '<i class="fa-regular fa-square"></i>';
        readToggle.onclick = async () => {
            try {
                const response = await fetch(`/entries/${entry.id}/state`, {
                    method: 'PATCH',
                    headers: {
                        'Content-Type': 'application/json',
                    },
                    body: JSON.stringify({
                        read: !entry.marked_read
                    })
                });

                if (response.ok) {
                    entry.marked_read = !entry.marked_read;
                    readToggle.title = entry.marked_read ? 'Mark as unread' : 'Mark as read';
                    readToggle.innerHTML = entry.marked_read 
                        ? '<i class="fa-solid fa-square-check"></i>'
                        : '<i class="fa-regular fa-square"></i>';
                } else {
                    console.error('Failed to update read state:', response.status);
                }
            } catch (error) {
                console.error('Failed to update read state:', error);
            }
        };
        title.appendChild(readToggle);

        const titleLink = document.createElement('a');
        titleLink.href = entry.link || '#';
        titleLink.target = '_blank';
        titleLink.textContent = entry.title;
        titleLink.onclick = () => {
            if (!entry.marked_read) {
                // Mark as read in the background, don't wait for it
                fetch(`/entries/${entry.id}/state`, {
                    method: 'PATCH',
                    headers: {
                        'Content-Type': 'application/json',
                    },
                    body: JSON.stringify({
                        read: true
                    })
                }).then(response => {
                    if (response.ok) {
                        entry.marked_read = true;
                        readToggle.title = 'Mark as unread';
                        readToggle.innerHTML = '<i class="fa-solid fa-square-check"></i>';
                    } else {
                        console.error('Failed to update read state:', response.status);
                    }
                }).catch(error => {
                    console.error('Failed to update read state:', error);
                });
            }
            // Let the default link behavior happen immediately
        };
        title.appendChild(titleLink);

        const meta = document.createElement('div');
        meta.className = 'feed-entry-meta';
        if (entry.published) {
            const published = document.createElement('span');
            published.textContent = `Published: ${formatDate(entry.published)}`;
            meta.appendChild(published);
        }
        if (entry.updated) {
            const updated = document.createElement('span');
            updated.textContent = `Updated: ${formatDate(entry.updated)}`;
            meta.appendChild(updated);
        }

        const summary = document.createElement('div');
        summary.className = 'feed-entry-summary';
        summary.textContent = entry.summary;

        entryDiv.appendChild(title);
        entryDiv.appendChild(meta);
        entryDiv.appendChild(summary);
        mainContent.appendChild(entryDiv);
    });
}

function openFeed(feed) {
    const name = document.createElement('span');
    name.className = 'feed-name';
    name.textContent = feed.name;

    const spinner = document.createElement('div');
    spinner.className = 'feed-spinner';
    name.appendChild(spinner);

    name.onclick = async () => {
        name.classList.add('loading');
        try {
            const response = await fetch(`/poll/${feed.feed_id}`, {
                method: 'POST'
            });
            if (response.ok) {
                const data = await response.json();
                console.log('Feed poll response:', data);
                renderFeedEntries(data.entries);
                // Update the top bar title
                const topBarTitle = document.querySelector('.top-bar-title');
                topBarTitle.innerHTML = `RSS Reader <span class="feed-title-separator">-</span> ${feed.name}`;
                // Update the browser document title
                document.title = `RSS Reader - ${feed.name}`;
            } else {
                console.error('Failed to poll feed:', response.status);
            }
        } catch (error) {
            console.error('Error polling feed:', error);
        } finally {
            name.classList.remove('loading');
        }
    };

    const menuButton = document.createElement('button');
    menuButton.className = 'feed-menu-button';
    menuButton.innerHTML = '<i class="fas fa-ellipsis-v"></i>';
    menuButton.title = 'Feed options';
    menuButton.onclick = (e) => {
        e.stopPropagation();
        closeAllFeedMenus();
        menu.classList.toggle('show');
    };

    const menu = document.createElement('div');
    menu.className = 'feed-menu';

    const copyItem = document.createElement('a');
    copyItem.className = 'feed-menu-item copy';
    copyItem.innerHTML = '<span class="menu-icon"><i class="fas fa-copy"></i></span> Copy feed URL';
    copyItem.onclick = async (e) => {
        e.stopPropagation();
        try {
            await navigator.clipboard.writeText(feed.url);
            // Briefly show success feedback
            const originalText = copyItem.innerHTML;
            copyItem.innerHTML = '<span class="menu-icon"><i class="fas fa-check"></i></span> Copied!';
            setTimeout(() => {
                copyItem.innerHTML = originalText;
            }, 1500);
        } catch (error) {
            console.error('Failed to copy URL:', error);
        }
        menu.classList.remove('show');
    };

    const deleteItem = document.createElement('a');
    deleteItem.className = 'feed-menu-item delete';
    deleteItem.innerHTML = '<span class="menu-icon"><i class="fas fa-trash-alt"></i></span> Remove Feed';
    deleteItem.onclick = async (e) => {
        e.stopPropagation();
        if (confirm(`Are you sure you want to delete "${feed.name}"?`)) {
            try {
                const response = await fetch(`/feeds/${feed.feed_id}`, {
                    method: 'DELETE',
                });
                if (response.ok) {
                    handleFeeds();
                } else {
                    console.error('Failed to delete feed:', response.status);
                }
            } catch (error) {
                console.error('Error deleting feed:', error);
            }
        }
        menu.classList.remove('show');
    };

    menu.appendChild(copyItem);
    menu.appendChild(deleteItem);
    name.appendChild(menuButton);
    name.appendChild(menu);
    return name;
}

async function handleFeeds() {
    const feeds = await fetchFeeds();
    const feedList = document.getElementById('feedList');
    
    if (feeds) {
        console.log('Loaded feeds:', feeds);
        feedList.innerHTML = '';
        
        if (feeds.length === 0) {
            const emptyMessage = document.createElement('div');
            emptyMessage.className = 'feed-empty';
            emptyMessage.textContent = 'No feeds added yet';
            feedList.appendChild(emptyMessage);
        } else {
            // Group feeds by category
            const feedsByCategory = {};
            const uncategorizedFeeds = [];

            feeds.forEach(feed => {
                const category = feed.categorization.length > 0 ? feed.categorization[0] : null;
                if (category) {
                    if (!feedsByCategory[category]) {
                        feedsByCategory[category] = [];
                    }
                    feedsByCategory[category].push(feed);
                } else {
                    uncategorizedFeeds.push(feed);
                }
            });

            // Sort categories alphabetically, but keep "Uncategorized" at the end
            const sortedCategories = Object.keys(feedsByCategory).sort((a, b) => a.localeCompare(b));
            sortedCategories.push("<No Category>");
            feedsByCategory["<No Category>"] = uncategorizedFeeds;

            // Create category sections
            sortedCategories.forEach(category => {
                const categorySection = document.createElement('div');
                categorySection.className = 'feed-category';

                const categoryHeader = document.createElement('h3');
                categoryHeader.className = 'feed-category-header';
                categoryHeader.textContent = category;
                categorySection.appendChild(categoryHeader);

                // Add feeds for this category
                feedsByCategory[category].forEach(feed => {
                    categorySection.appendChild(openFeed(feed));
                });

                feedList.appendChild(categorySection);
            });
        }
    } else {
        feedList.innerHTML = '<div class="feed-error">Failed to load feeds</div>';
    }
}

// Load feeds when page loads
document.addEventListener('DOMContentLoaded', handleFeeds);

// User menu functionality
const userMenuButton = document.getElementById('userMenuButton');
const userMenuDropdown = document.getElementById('userMenuDropdown');

// Toggle menu on button click
userMenuButton.addEventListener('click', (e) => {
    e.stopPropagation();
    userMenuDropdown.classList.toggle('show');
});

// Close menu when clicking outside
document.addEventListener('click', (e) => {
    if (!e.target.closest('.user-menu')) {
        userMenuDropdown.classList.remove('show');
    }
});

// Prevent menu from closing when clicking inside it
userMenuDropdown.addEventListener('click', (e) => {
    e.stopPropagation();
});

// Logout functionality
document.getElementById('logoutButton').addEventListener('click', async () => {
    try {
        const response = await fetch('/logout', {
            method: 'POST',
        });

        if (response.ok) {
            window.location.href = '/login';
        }
    } catch (error) {
        console.error('Logout failed:', error);
    }
});

// Modal functionality
const modal = document.getElementById('addFeedModal');
const addFeedButton = document.getElementById('addFeedButton');
const cancelButton = document.getElementById('cancelAddFeed');
const confirmButton = document.getElementById('confirmAddFeed');
const addFeedForm = document.getElementById('addFeedForm');
const errorMessage = document.getElementById('feedErrorMessage');
const loadingMessage = document.getElementById('loadingMessage');

function showModal() {
    modal.classList.add('show');
    errorMessage.style.display = 'none';
    loadingMessage.style.display = 'none';
    addFeedForm.reset();
    confirmButton.disabled = false;
}

function hideModal() {
    modal.classList.remove('show');
    errorMessage.style.display = 'none';
    loadingMessage.style.display = 'none';
    addFeedForm.reset();
    confirmButton.disabled = false;
}

function showError(message) {
    errorMessage.textContent = message;
    errorMessage.style.display = 'block';
    loadingMessage.style.display = 'none';
    confirmButton.disabled = false;
}

function showLoading() {
    loadingMessage.style.display = 'block';
    errorMessage.style.display = 'none';
    confirmButton.disabled = true;
}

addFeedButton.addEventListener('click', showModal);
cancelButton.addEventListener('click', hideModal);

// Close modal when clicking outside
modal.addEventListener('click', (e) => {
    if (e.target === modal) {
        hideModal();
    }
});

confirmButton.addEventListener('click', async () => {
    const url = document.getElementById('feedUrl').value.trim();

    if (!url) {
        showError('Please enter a feed URL');
        return;
    }

    showLoading();

    try {
        const response = await fetch('/feeds', {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json',
            },
            body: JSON.stringify({ url }),
        });

        if (response.ok) {
            hideModal();
            // Refresh the feed list
            handleFeeds();
        } else {
            switch (response.status) {
                case 409:
                    showError('You already have this feed added');
                    break;
                case 422:
                    showError('Invalid feed URL. Please make sure it\'s a valid RSS or Atom feed.');
                    break;
                default:
                    showError('Failed to add feed. Please try again.');
            }
        }
    } catch (error) {
        console.error('Add feed failed:', error);
        showError('An error occurred. Please try again.');
    }
});