document.addEventListener('DOMContentLoaded', function () {
    const alarmForm = document.getElementById('alarm-form');
    const alarmsList = document.getElementById('alarms-list');
    const alarmModal = new bootstrap.Modal(document.getElementById('alarm-modal'));
    const alarmSound = document.getElementById('alarm-sound');
    const dismissAlarmBtn = document.getElementById('dismiss-alarm');
    const enableNotificationsBtn = document.getElementById('enable-notifications');

    let notificationPermission = false;

    // Request notification permission
    if (enableNotificationsBtn) {
        enableNotificationsBtn.addEventListener('click', () => {
            Notification.requestPermission().then(permission => {
                if (permission === 'granted') {
                    notificationPermission = true;
                    alert('Notifications enabled!');
                    enableNotificationsBtn.style.display = 'none';
                } else {
                    alert('Notification permission denied.');
                }
            });
        });
    }


    // Function to fetch and display alarms
    const fetchAlarms = () => {
        fetch('/api/alarms.php?action=get')
            .then(response => response.json())
            .then(data => {
                alarmsList.innerHTML = '';
                if (data.success) {
                    data.alarms.forEach(alarm => {
                        addAlarmToList(alarm.id, alarm.alarm_time, alarm.note_id, alarm.is_active);
                    });
                }
            });
    };

    // Function to add a single alarm to the list
    const addAlarmToList = (id, time, noteId, isActive) => {
        const listItem = document.createElement('li');
        listItem.className = 'list-group-item d-flex justify-content-between align-items-center';
        listItem.dataset.id = id;

        const timeText = document.createElement('span');
        timeText.textContent = new Date(`1970-01-01T${time}`).toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });

        const noteLink = document.createElement('a');
        noteLink.href = `/note.php?id=${noteId}`;
        noteLink.textContent = `Note #${noteId}`;
        noteLink.className = 'mx-3';

        const controls = document.createElement('div');

        const toggleSwitch = document.createElement('div');
        toggleSwitch.className = 'form-check form-switch';
        const toggleInput = document.createElement('input');
        toggleInput.className = 'form-check-input';
        toggleInput.type = 'checkbox';
        toggleInput.role = 'switch';
        toggleInput.checked = isActive;
        toggleInput.addEventListener('change', () => handleToggleAlarm(id, toggleInput.checked));
        toggleSwitch.appendChild(toggleInput);

        const deleteBtn = document.createElement('button');
        deleteBtn.className = 'btn btn-danger btn-sm ms-3';
        deleteBtn.textContent = 'Delete';
        deleteBtn.addEventListener('click', () => handleDeleteAlarm(id));

        controls.appendChild(toggleSwitch);
        controls.appendChild(deleteBtn);

        listItem.appendChild(timeText);
        listItem.appendChild(noteLink);
        listItem.appendChild(controls);
        alarmsList.appendChild(listItem);
    };

    // Handle form submission to create a new alarm
    if (alarmForm) {
        alarmForm.addEventListener('submit', function (e) {
            e.preventDefault();
            const formData = new FormData(alarmForm);
            fetch('/api/alarms.php?action=create', {
                method: 'POST',
                body: formData
            })
                .then(response => response.json())
                .then(data => {
                    if (data.success) {
                        addAlarmToList(data.id, data.alarm_time, data.note_id, true);
                        alarmForm.reset();
                    } else {
                        alert('Error: ' + data.error);
                    }
                });
        });
    }

    // Handle deleting an alarm
    const handleDeleteAlarm = (id) => {
        if (!confirm('Are you sure you want to delete this alarm?')) return;
        fetch(`/api/alarms.php?action=delete&id=${id}`, { method: 'GET' })
            .then(response => response.json())
            .then(data => {
                if (data.success) {
                    document.querySelector(`li[data-id='${id}']`).remove();
                } else {
                    alert('Error: ' + data.error);
                }
            });
    };

    // Handle toggling an alarm's active state
    const handleToggleAlarm = (id, isActive) => {
        const formData = new FormData();
        formData.append('id', id);
        formData.append('is_active', isActive ? 1 : 0);

        fetch('/api/alarms.php?action=toggle', {
            method: 'POST',
            body: formData
        }).then(response => response.json())
          .then(data => {
              if (!data.success) {
                  alert('Error updating alarm status.');
              }
          });
    };


    // Function to check for due alarms
    const checkAlarms = () => {
        fetch('/api/alarms.php?action=check')
            .then(response => response.json())
            .then(data => {
                if (data.success && data.alarms.length > 0) {
                    const alarm = data.alarms[0]; // Assuming one alarm for now
                    showNotification(alarm);
                    // Also update the toggle on the main page
                    const alarmToggle = document.querySelector(`li[data-id='${alarm.id}'] input[type='checkbox']`);
                    if (alarmToggle) {
                        alarmToggle.checked = false;
                    }
                }
            });
    };

    // Function to show notification
    const showNotification = (alarm) => {
        const alarmTime = new Date(`1970-01-01T${alarm.alarm_time}`).toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
        const notificationTitle = `Alarm! It's ${alarmTime}`;
        const notificationBody = `Click to open your note.`;

        if (notificationPermission) {
            const notification = new Notification(notificationTitle, {
                body: notificationBody,
                icon: '/assets/images/bell.png', // Optional: add an icon
                sound: '/assets/sounds/alarm.mp3', // This doesn't work, sound is handled separately
                requireInteraction: true // Keeps notification open until user interacts
            });

            notification.onclick = () => {
                window.open(`/note.php?id=${alarm.note_id}`, '_blank');
                notification.close();
            };
        }

        // Fallback to modal
        alarmSound.play().catch(e => console.error("Audio playback failed:", e));
        alarmModal.show();

        dismissAlarmBtn.onclick = () => {
            alarmSound.pause();
            alarmSound.currentTime = 0;
            alarmModal.hide();
        };
    };


    // Initial fetch and periodic check
    fetchAlarms();
    setInterval(checkAlarms, 5000); // Check every 5 seconds
});