/**
 * KeepItGoing - Main Application JavaScript
 * Handles theme toggle, task selection, mobile menus, and AJAX operations
 */

document.addEventListener('DOMContentLoaded', function() {
    initTheme();
    initTaskSelection();
    initTimerDisplays();
});

/* ============================================
   Theme Toggle
   ============================================ */

function initTheme() {
    // Check for saved theme preference or system preference
    const savedTheme = localStorage.getItem('theme');
    const systemDark = window.matchMedia('(prefers-color-scheme: dark)').matches;

    if (savedTheme) {
        setTheme(savedTheme);
    } else if (systemDark) {
        setTheme('dark');
    }

    // Listen for system theme changes
    window.matchMedia('(prefers-color-scheme: dark)').addEventListener('change', e => {
        if (!localStorage.getItem('theme')) {
            setTheme(e.matches ? 'dark' : 'light');
        }
    });
}

function toggleTheme() {
    const currentTheme = document.documentElement.getAttribute('data-theme') || 'light';
    const newTheme = currentTheme === 'dark' ? 'light' : 'dark';
    setTheme(newTheme);
    localStorage.setItem('theme', newTheme);
}

function setTheme(theme) {
    document.documentElement.setAttribute('data-theme', theme);

    // Update theme toggle icon
    const lightIcon = document.getElementById('theme-icon-light');
    const darkIcon = document.getElementById('theme-icon-dark');

    if (lightIcon && darkIcon) {
        if (theme === 'dark') {
            lightIcon.style.display = 'none';
            darkIcon.style.display = 'block';
        } else {
            lightIcon.style.display = 'block';
            darkIcon.style.display = 'none';
        }
    }
}

/* ============================================
   Task Selection
   ============================================ */

function initTaskSelection() {
    // Add click handlers to task items
    const taskItems = document.querySelectorAll('.task-item');
    taskItems.forEach(item => {
        item.addEventListener('click', function(e) {
            // Don't select if clicking checkbox form
            if (e.target.closest('.task-toggle')) {
                return;
            }
            const taskId = this.dataset.taskId;
            if (taskId) {
                selectTask(taskId);
            }
        });
    });
}

function selectTask(taskId) {
    // Update URL without full page reload
    const url = new URL(window.location);
    url.searchParams.set('selected', taskId);
    window.history.pushState({}, '', url);

    // Update visual selection
    document.querySelectorAll('.task-item').forEach(item => {
        item.classList.remove('selected');
    });
    const selectedItem = document.querySelector(`.task-item[data-task-id="${taskId}"]`);
    if (selectedItem) {
        selectedItem.classList.add('selected');
    }

    // Load task detail via AJAX
    loadTaskDetail(taskId);
}

function loadTaskDetail(taskId) {
    const detailPane = document.getElementById('detail-pane');
    const appLayout = document.getElementById('app');

    if (!detailPane) return;

    // Show loading state
    detailPane.innerHTML = '<div class="empty-state"><p>Loading...</p></div>';
    detailPane.classList.remove('hidden');
    if (appLayout) {
        appLayout.classList.remove('detail-closed');
    }

    // On mobile, show detail pane
    if (window.innerWidth <= 1024) {
        detailPane.classList.add('open');
        document.getElementById('mobile-overlay').classList.add('visible');
    }

    // Fetch task detail HTML
    fetch(`/tasks/${taskId}/detail-partial/`)
        .then(response => {
            if (!response.ok) throw new Error('Failed to load task');
            return response.text();
        })
        .then(html => {
            detailPane.innerHTML = html;
        })
        .catch(error => {
            console.error('Error loading task detail:', error);
            detailPane.innerHTML = `
                <div class="empty-state">
                    <p class="text-danger">Failed to load task details</p>
                    <p class="text-muted">Please refresh the page</p>
                </div>
            `;
        });
}

function closeDetail() {
    const detailPane = document.getElementById('detail-pane');
    const appLayout = document.getElementById('app');

    if (detailPane) {
        detailPane.classList.add('hidden');
        detailPane.classList.remove('open');
    }
    if (appLayout) {
        appLayout.classList.add('detail-closed');
    }

    // Clear selection
    document.querySelectorAll('.task-item').forEach(item => {
        item.classList.remove('selected');
    });

    // Update URL
    const url = new URL(window.location);
    url.searchParams.delete('selected');
    window.history.pushState({}, '', url);

    // Close mobile overlay
    closeMobileMenus();
}

/* ============================================
   Mobile Navigation
   ============================================ */

function toggleSidebar() {
    const sidebar = document.getElementById('sidebar');
    const overlay = document.getElementById('mobile-overlay');

    if (sidebar) {
        sidebar.classList.toggle('open');
    }
    if (overlay) {
        overlay.classList.toggle('visible', sidebar.classList.contains('open'));
    }
}

function closeMobileMenus() {
    const sidebar = document.getElementById('sidebar');
    const detailPane = document.getElementById('detail-pane');
    const overlay = document.getElementById('mobile-overlay');

    if (sidebar) {
        sidebar.classList.remove('open');
    }
    if (detailPane) {
        detailPane.classList.remove('open');
    }
    if (overlay) {
        overlay.classList.remove('visible');
    }
}

/* ============================================
   Timer Displays
   ============================================ */

function initTimerDisplays() {
    // Handle running timer in header/dashboard
    const runningTimer = document.getElementById('running-timer');
    if (runningTimer) {
        const startedAt = new Date(runningTimer.dataset.started);
        updateTimerDisplay(runningTimer, startedAt);
        setInterval(() => updateTimerDisplay(runningTimer, startedAt), 1000);
    }
}

function updateTimerDisplay(element, startedAt) {
    const now = new Date();
    const diff = Math.floor((now - startedAt) / 1000);
    const hours = Math.floor(diff / 3600).toString().padStart(2, '0');
    const minutes = Math.floor((diff % 3600) / 60).toString().padStart(2, '0');
    const seconds = (diff % 60).toString().padStart(2, '0');
    element.textContent = `${hours}:${minutes}:${seconds}`;
}

/* ============================================
   Utility Functions
   ============================================ */

function formatDuration(seconds) {
    if (seconds < 60) {
        return `${seconds}s`;
    } else if (seconds < 3600) {
        const mins = Math.floor(seconds / 60);
        return `${mins}m`;
    } else {
        const hours = Math.floor(seconds / 3600);
        const mins = Math.floor((seconds % 3600) / 60);
        return `${hours}h ${mins}m`;
    }
}

function formatRelativeDate(dateString) {
    const date = new Date(dateString);
    const today = new Date();
    today.setHours(0, 0, 0, 0);

    const tomorrow = new Date(today);
    tomorrow.setDate(tomorrow.getDate() + 1);

    const yesterday = new Date(today);
    yesterday.setDate(yesterday.getDate() - 1);

    const dateOnly = new Date(date);
    dateOnly.setHours(0, 0, 0, 0);

    if (dateOnly.getTime() === today.getTime()) {
        return 'Today';
    } else if (dateOnly.getTime() === tomorrow.getTime()) {
        return 'Tomorrow';
    } else if (dateOnly.getTime() === yesterday.getTime()) {
        return 'Yesterday';
    } else {
        return date.toLocaleDateString();
    }
}

/* ============================================
   Handle Browser Back/Forward
   ============================================ */

window.addEventListener('popstate', function(e) {
    const url = new URL(window.location);
    const selectedTaskId = url.searchParams.get('selected');

    if (selectedTaskId) {
        // Show the selected task
        document.querySelectorAll('.task-item').forEach(item => {
            item.classList.remove('selected');
        });
        const selectedItem = document.querySelector(`.task-item[data-task-id="${selectedTaskId}"]`);
        if (selectedItem) {
            selectedItem.classList.add('selected');
        }
        loadTaskDetail(selectedTaskId);
    } else {
        // Close detail panel
        closeDetail();
    }
});

/* ============================================
   Group Modal
   ============================================ */

let currentGroupId = null;
let selectedColor = '#3b82f6';

document.addEventListener('DOMContentLoaded', function() {
    initGroupModal();
});

function initGroupModal() {
    // Setup backdrop click to close
    const backdrop = document.getElementById('group-modal-backdrop');
    if (backdrop) {
        backdrop.addEventListener('click', function(e) {
            if (e.target === backdrop) {
                closeGroupModal();
            }
        });
    }

    // Setup color preset buttons
    document.querySelectorAll('.color-preset').forEach(btn => {
        btn.addEventListener('click', function() {
            selectColor(this.dataset.color);
        });
    });

    // Setup custom color picker
    const colorPicker = document.getElementById('group-color');
    if (colorPicker) {
        colorPicker.addEventListener('input', function() {
            selectColor(this.value, true);
        });
    }

    // Setup name field for preview
    const nameField = document.getElementById('group-name');
    if (nameField) {
        nameField.addEventListener('input', updateGroupPreview);
    }

    // Setup form submission
    const form = document.getElementById('group-form');
    if (form) {
        form.addEventListener('submit', handleGroupSubmit);
    }
}

// Make openGroupModal globally available for onclick handlers
window.openGroupModal = function(groupId = null, name = '', color = '#3b82f6') {
    console.log('openGroupModal called:', { groupId, name, color });

    const backdrop = document.getElementById('group-modal-backdrop');
    const title = document.getElementById('group-modal-title');
    const nameField = document.getElementById('group-name');
    const deleteBtn = document.getElementById('group-delete-btn');
    const submitBtn = document.getElementById('group-submit-btn');
    const groupIdField = document.getElementById('group-id');

    if (!backdrop) {
        console.error('Modal backdrop not found!');
        return;
    }

    currentGroupId = groupId;

    if (groupId) {
        // Edit mode
        if (title) title.textContent = 'Edit Group';
        if (nameField) nameField.value = name;
        if (deleteBtn) deleteBtn.style.display = 'inline-flex';
        if (submitBtn) submitBtn.textContent = 'Save';
        if (groupIdField) groupIdField.value = groupId;
    } else {
        // Create mode
        if (title) title.textContent = 'New Group';
        if (nameField) nameField.value = '';
        if (deleteBtn) deleteBtn.style.display = 'none';
        if (submitBtn) submitBtn.textContent = 'Create';
        if (groupIdField) groupIdField.value = '';
        color = '#3b82f6';
    }

    selectColor(color);
    updateGroupPreview();

    backdrop.classList.add('open');
    console.log('Modal should now be open');
    if (nameField) nameField.focus();
};

// Make closeGroupModal globally available for onclick handlers
window.closeGroupModal = function() {
    const backdrop = document.getElementById('group-modal-backdrop');
    if (backdrop) {
        backdrop.classList.remove('open');
    }
    currentGroupId = null;
};

function selectColor(color, isCustom = false) {
    selectedColor = color;

    // Update preset button selection
    document.querySelectorAll('.color-preset').forEach(btn => {
        btn.classList.toggle('selected', btn.dataset.color.toLowerCase() === color.toLowerCase());
    });

    // Update custom color picker if not already from custom
    if (!isCustom) {
        const colorPicker = document.getElementById('group-color');
        if (colorPicker) {
            colorPicker.value = color;
        }
    }

    // Update hidden field
    const hiddenField = document.getElementById('group-color-hidden');
    if (hiddenField) {
        hiddenField.value = color;
    }

    // Update preview
    updateGroupPreview();
}

function updateGroupPreview() {
    const nameField = document.getElementById('group-name');
    const previewDot = document.getElementById('group-preview-dot');
    const previewName = document.getElementById('group-preview-name');

    if (previewDot) {
        previewDot.style.backgroundColor = selectedColor;
    }
    if (previewName && nameField) {
        previewName.textContent = nameField.value || 'Group Preview';
        previewName.style.color = nameField.value ? 'var(--text-primary)' : 'var(--text-muted)';
    }
}

function handleGroupSubmit(e) {
    e.preventDefault();

    const nameField = document.getElementById('group-name');
    const name = nameField.value.trim();

    if (!name) {
        nameField.focus();
        return;
    }

    const csrfToken = document.querySelector('[name=csrfmiddlewaretoken]').value;
    const formData = new FormData();
    formData.append('name', name);
    formData.append('color', selectedColor);
    formData.append('csrfmiddlewaretoken', csrfToken);

    let url, method;
    if (currentGroupId) {
        // Update existing group
        url = `/groups/${currentGroupId}/`;
        formData.append('next', window.location.pathname + window.location.search);
    } else {
        // Create new group
        url = '/groups/';
        formData.append('next', window.location.pathname + window.location.search);
    }

    fetch(url, {
        method: 'POST',
        body: formData,
        headers: {
            'X-Requested-With': 'XMLHttpRequest'
        }
    })
    .then(response => {
        if (response.redirected) {
            window.location.href = response.url;
        } else if (response.ok) {
            window.location.reload();
        } else {
            throw new Error('Failed to save group');
        }
    })
    .catch(error => {
        console.error('Error saving group:', error);
        alert('Failed to save group. Please try again.');
    });
}

// Make deleteGroup globally available for onclick handlers
window.deleteGroup = function() {
    if (!currentGroupId) return;

    if (!confirm('Are you sure you want to delete this group?\n\nTasks in this group will not be deleted.')) {
        return;
    }

    const csrfToken = document.querySelector('[name=csrfmiddlewaretoken]').value;
    const formData = new FormData();
    formData.append('csrfmiddlewaretoken', csrfToken);
    formData.append('next', window.location.pathname + window.location.search);

    fetch(`/groups/${currentGroupId}/delete/`, {
        method: 'POST',
        body: formData,
        headers: {
            'X-Requested-With': 'XMLHttpRequest'
        }
    })
    .then(response => {
        if (response.redirected) {
            window.location.href = response.url;
        } else if (response.ok) {
            window.location.reload();
        } else {
            throw new Error('Failed to delete group');
        }
    })
    .catch(error => {
        console.error('Error deleting group:', error);
        alert('Failed to delete group. Please try again.');
    });
};

/* ============================================
   Tag Modal
   ============================================ */

let currentTagId = null;
let selectedTagColor = '#3b82f6';

document.addEventListener('DOMContentLoaded', function() {
    initTagModal();
});

function initTagModal() {
    // Setup backdrop click to close
    const backdrop = document.getElementById('tag-modal-backdrop');
    if (backdrop) {
        backdrop.addEventListener('click', function(e) {
            if (e.target === backdrop) {
                closeTagModal();
            }
        });
    }

    // Setup color preset buttons
    document.querySelectorAll('.color-preset').forEach(btn => {
        btn.addEventListener('click', function() {
            selectTagColor(this.dataset.color);
        });
    });

    // Setup custom color picker
    const colorPicker = document.getElementById('tag-color');
    if (colorPicker) {
        colorPicker.addEventListener('input', function() {
            selectTagColor(this.value, true);
        });
    }

    // Setup form submission
    const form = document.getElementById('tag-form');
    if (form) {
        form.addEventListener('submit', handleTagSubmit);
    }
}

function handleTagSubmit(e) {
    e.preventDefault();

    const nameField = document.getElementById('tag-name');
    const name = nameField.value.trim();

    if (!name) {
        nameField.focus();
        return;
    }

    const csrfToken = document.querySelector('[name=csrfmiddlewaretoken]').value;
    const formData = new FormData();
    formData.append('name', name);
    formData.append('color', selectedTagColor);
    formData.append('csrfmiddlewaretoken', csrfToken);

    let url;
    if (currentTagId) {
        // Update existing tag
        url = `/tags/${currentTagId}/`;
        formData.append('next', window.location.pathname + window.location.search);
    } else {
        // Create new tag
        url = '/tags/';
        formData.append('next', window.location.pathname + window.location.search);
    }

    fetch(url, {
        method: 'POST',
        body: formData,
        headers: {
            'X-Requested-With': 'XMLHttpRequest'
        }
    })
    .then(response => {
        if (response.redirected) {
            window.location.href = response.url;
        } else if (response.ok) {
            window.location.reload();
        } else {
            throw new Error('Failed to save tag');
        }
    })
    .catch(error => {
        console.error('Error saving tag:', error);
        alert('Failed to save tag. Please try again.');
    });
}

// Make openTagModal globally available for onclick handlers
window.openTagModal = function(tagId = null, name = '', color = '#3b82f6') {
    console.log('openTagModal called:', { tagId, name, color });

    const backdrop = document.getElementById('tag-modal-backdrop');
    const title = document.getElementById('tag-modal-title');
    const nameField = document.getElementById('tag-name');
    const deleteBtn = document.getElementById('tag-delete-btn');
    const submitBtn = document.getElementById('tag-submit-btn');
    const tagIdField = document.getElementById('tag-id');

    if (!backdrop) {
        console.error('Tag modal backdrop not found!');
        return;
    }

    currentTagId = tagId;

    if (tagId) {
        // Edit mode
        if (title) title.textContent = 'Edit Tag';
        if (nameField) nameField.value = name;
        if (deleteBtn) deleteBtn.style.display = 'inline-flex';
        if (submitBtn) submitBtn.textContent = 'Save';
        if (tagIdField) tagIdField.value = tagId;
    } else {
        // Create mode
        if (title) title.textContent = 'New Tag';
        if (nameField) nameField.value = '';
        if (deleteBtn) deleteBtn.style.display = 'none';
        if (submitBtn) submitBtn.textContent = 'Create';
        if (tagIdField) tagIdField.value = '';
        color = '#3b82f6';
    }

    selectTagColor(color);
    backdrop.classList.add('open');
    if (nameField) nameField.focus();
};

// Make closeTagModal globally available for onclick handlers
window.closeTagModal = function() {
    const backdrop = document.getElementById('tag-modal-backdrop');
    if (backdrop) {
        backdrop.classList.remove('open');
    }
    currentTagId = null;
};

function selectTagColor(color) {
    selectedTagColor = color;

    // Update preset button selection
    document.querySelectorAll('.color-preset').forEach(btn => {
        btn.classList.toggle('selected', btn.dataset.color.toLowerCase() === color.toLowerCase());
    });

    // Update custom color picker
    const colorPicker = document.getElementById('tag-color');
    if (colorPicker) {
        colorPicker.value = color;
    }

    // Update hidden field
    const hiddenField = document.getElementById('tag-color-hidden');
    if (hiddenField) {
        hiddenField.value = color;
    }
}

// Make deleteTag globally available for onclick handlers
window.deleteTag = function() {
    if (!currentTagId) return;

    if (!confirm('Are you sure you want to delete this tag?\n\nTasks with this tag will not be deleted.')) {
        return;
    }

    const csrfToken = document.querySelector('[name=csrfmiddlewaretoken]').value;
    const formData = new FormData();
    formData.append('csrfmiddlewaretoken', csrfToken);
    formData.append('next', window.location.pathname + window.location.search);

    fetch(`/tags/${currentTagId}/delete/`, {
        method: 'POST',
        body: formData,
        headers: {
            'X-Requested-With': 'XMLHttpRequest'
        }
    })
    .then(response => {
        if (response.redirected) {
            window.location.href = response.url;
        } else if (response.ok) {
            window.location.reload();
        } else {
            throw new Error('Failed to delete tag');
        }
    })
    .catch(error => {
        console.error('Error deleting tag:', error);
        alert('Failed to delete tag. Please try again.');
    });
};