blog/themes/Ying/assets/js/modules/floating-tools.js

window.initFloatingTools = function() {
    try {
        // 0. Global Toolbar Visibility (Homepage Check)
        var container = document.querySelector('.floating-tools');
        
        // Robust Homepage Check:
        // 1. Check for Homepage-specific element (.recent-posts)
        // 2. Ensure NOT on a Post page (.post-content)
        // 3. Fallback: Check pathname (only if DOM check is ambiguous)
        var hasRecentPosts = document.querySelector('.recent-posts');
        var hasPostContent = document.querySelector('.post-content');
        
        var isHomePage = false;
        if (hasRecentPosts && !hasPostContent) {
            isHomePage = true;
        } else if (!hasRecentPosts && !hasPostContent) {
            // Could be Archive or Custom Page. Check Path.
            var path = window.location.pathname;
            if (path === '/' || path === '/index.html' || path.startsWith('/page/')) {
                isHomePage = true;
            }
        }

        if (container) {
            if (isHomePage) {
                container.style.display = 'none';
                // Do not return here, let other logic run in case we need to reset state
                // But for performance, we can skip binding if hidden? 
                // No, better to bind so if it becomes visible later (unlikely without PJAX) it works.
                // Actually, with PJAX, this function runs again. So we can just hide it.
            } else {
                container.style.display = ''; // Restore display
            }
        }

        // 1. Back to Top (Optimized with IntersectionObserver)
        var backToTopButton = document.getElementById('back-to-top');
        if (backToTopButton) {
            
            // Clean up old scroll handler if exists (from previous Pjax or version)
            if (window.backToTopScrollHandler) {
                window.removeEventListener('scroll', window.backToTopScrollHandler);
                window.backToTopScrollHandler = null;
            }

            // Create or reuse sentinel for IntersectionObserver
            var sentinelId = 'back-to-top-sentinel';
            var sentinel = document.getElementById(sentinelId);
            if (!sentinel) {
                sentinel = document.createElement('div');
                sentinel.id = sentinelId;
                // Sentinel covers the top 300px. When it exits viewport, we show button.
                sentinel.style.cssText = 'position: absolute; top: 0; left: 0; width: 1px; height: 300px; pointer-events: none; visibility: hidden; z-index: -9999;';
                document.body.appendChild(sentinel);
            }

            if (window.IntersectionObserver) {
                var observer = new IntersectionObserver(function(entries) {
                    entries.forEach(function(entry) {
                        if (!entry.isIntersecting) {
                            // Sentinel is out of view (scrolled down past 300px)
                            backToTopButton.classList.add('show');
                        } else {
                            // Sentinel is in view (near top)
                            backToTopButton.classList.remove('show');
                        }
                    });
                });
                observer.observe(sentinel);
            } else {
                // Fallback for very old browsers
                var ticking = false;
                var update = function() {
                    if (window.scrollY > 300) {
                        backToTopButton.classList.add('show');
                    } else {
                        backToTopButton.classList.remove('show');
                    }
                    ticking = false;
                };
                window.backToTopScrollHandler = function() {
                    if (!ticking) {
                        window.requestAnimationFrame(update);
                        ticking = true;
                    }
                };
                window.addEventListener('scroll', window.backToTopScrollHandler, { passive: true });
            }

            // Re-bind click event
            var newBtn = backToTopButton.cloneNode(true);
            if (backToTopButton.parentNode) {
                backToTopButton.parentNode.replaceChild(newBtn, backToTopButton);
                backToTopButton = newBtn;
            }

            backToTopButton.addEventListener('click', function(e) {
                e.preventDefault();
                window.scrollTo({
                    top: 0,
                    behavior: 'smooth'
                });
            });
        }

        // 2. Theme Toggle
        var themeToggle = document.getElementById('theme-toggle');
        if (themeToggle) {
             var newToggle = themeToggle.cloneNode(true);
             if (themeToggle.parentNode) {
                themeToggle.parentNode.replaceChild(newToggle, themeToggle);
                themeToggle = newToggle;
             }

             // Update icon based on current theme
             var updateIcon = function() {
                 var currentTheme = document.documentElement.getAttribute('data-theme');
                 var icon = themeToggle.querySelector('i');
                 if (icon) {
                     if (currentTheme === 'dark') {
                         icon.className = 'ri-moon-line';
                     } else {
                         icon.className = 'ri-sun-line';
                     }
                 }
             };
             updateIcon();

             themeToggle.addEventListener('click', function() {
                 var currentTheme = document.documentElement.getAttribute('data-theme');
                 var newTheme = currentTheme === 'dark' ? 'light' : 'dark';
                 document.documentElement.setAttribute('data-theme', newTheme);
                 localStorage.setItem('theme', newTheme);
                 updateIcon();
                 
                 // Trigger Artalk theme update
                 if (window.artalk && typeof window.artalk.setDarkMode === 'function') {
                     window.artalk.setDarkMode(newTheme === 'dark');
                 }

                 if (window.showToast) {
                     window.showToast('已切换至 ' + (newTheme === 'dark' ? '深色' : '浅色') + '模式', 'success');
                 }
             });
        }

        // 3. To Comments
        var toComments = document.getElementById('to-comments');
        if (toComments) {
            // Logic: Only show if comments section exists
            var checkCommentVisibility = function(btn) {
                if (!btn) return;
                var hasComments = document.getElementById('Comments') || document.querySelector('.artalk');
                
                if (hasComments) {
                    btn.style.display = ''; // Show
                } else {
                    btn.style.display = 'none'; // Hide
                }
            };

            // Initial check
            // Use setTimeout to avoid initial render flickering
            setTimeout(function() {
                checkCommentVisibility(toComments);
            }, 100);

            var newToComments = toComments.cloneNode(true);
            if (toComments.parentNode) {
                toComments.parentNode.replaceChild(newToComments, toComments);
                toComments = newToComments;
            }

            // Re-run check on new element
            checkCommentVisibility(toComments);
            
            // Double-check after a delay for PJAX/Async rendering
            setTimeout(function() {
                var currentBtn = document.getElementById('to-comments');
                if (currentBtn) {
                    checkCommentVisibility(currentBtn);
                }
            }, 500);

            toComments.addEventListener('click', function(e) {
                e.preventDefault();
                var comments = document.getElementById('Comments') || document.querySelector('.artalk');
                if (comments) {
                    comments.scrollIntoView({ behavior: 'smooth' });
                }
            });
        }
    } catch (e) {
        console.error('Error in initFloatingTools:', e);
    }
};