|
| 1 | +--- |
| 2 | +interface Props { |
| 3 | + sections: Array<{ |
| 4 | + id: string; |
| 5 | + title: string; |
| 6 | + }>; |
| 7 | + title?: string; |
| 8 | +} |
| 9 | +
|
| 10 | +const { sections, title = "On this page" } = Astro.props; |
| 11 | +--- |
| 12 | + |
| 13 | +<nav class="sidebar-nav"> |
| 14 | + <p>{title}</p> |
| 15 | + <ul> |
| 16 | + {sections.map((section) => ( |
| 17 | + <li> |
| 18 | + <a href={`#${section.id}`} data-section={section.id}> |
| 19 | + {section.title} |
| 20 | + </a> |
| 21 | + </li> |
| 22 | + ))} |
| 23 | + </ul> |
| 24 | +</nav> |
| 25 | + |
| 26 | +<style lang="scss"> |
| 27 | + .sidebar-nav { |
| 28 | + height: fit-content; |
| 29 | + padding: 1rem; |
| 30 | + background: var(--surface-frame-bg); |
| 31 | + border-radius: 8px; |
| 32 | + box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1); |
| 33 | + |
| 34 | + &::-webkit-scrollbar { |
| 35 | + width: 4px; |
| 36 | + } |
| 37 | + |
| 38 | + &::-webkit-scrollbar-track { |
| 39 | + background: transparent; |
| 40 | + } |
| 41 | + |
| 42 | + &::-webkit-scrollbar-thumb { |
| 43 | + background: var(--text-body-secondary); |
| 44 | + border-radius: 2px; |
| 45 | + } |
| 46 | + |
| 47 | + p{ |
| 48 | + margin-bottom: 1rem; |
| 49 | + border-bottom: 1px solid var(--text-body-secondary); |
| 50 | + @include typography(paragraph); |
| 51 | + font-size: calc(0.75rem * var(--font-scale-factor)); |
| 52 | + } |
| 53 | + |
| 54 | + ul { |
| 55 | + list-style: none; |
| 56 | + padding: 0; |
| 57 | + margin: 0; |
| 58 | + display: flex; |
| 59 | + flex-direction: column; |
| 60 | + gap: 0.5rem; |
| 61 | + |
| 62 | + li { |
| 63 | + margin: 0; |
| 64 | + padding: 0; |
| 65 | + |
| 66 | + a { |
| 67 | + display: block; |
| 68 | + padding: 0.2rem 0.5rem; |
| 69 | + text-decoration: none; |
| 70 | + color: var(--text-body-primary); |
| 71 | + transition: all 0.2s ease; |
| 72 | + @include typography(menu); |
| 73 | + font-size: calc(0.9rem * var(--font-scale-factor)); |
| 74 | + |
| 75 | + &:hover { |
| 76 | + background: var(--surface-main-primary); |
| 77 | + color: white; |
| 78 | + } |
| 79 | + |
| 80 | + &.active { |
| 81 | + border-right: 4px solid var(--surface-main-primary); |
| 82 | + } |
| 83 | + } |
| 84 | + } |
| 85 | + } |
| 86 | + } |
| 87 | +</style> |
| 88 | + |
| 89 | +<script> |
| 90 | + // Only run this script if the sidebar nav exists on the page |
| 91 | + const sidebarNav = document.querySelector('.sidebar-nav'); |
| 92 | + if (sidebarNav) { |
| 93 | + // Initialize sections visibility and currently active section |
| 94 | + const visibilityMap: Record<string, number> = {}; |
| 95 | + let currentActiveSection: string | null = null; |
| 96 | + |
| 97 | + // Thresholds for visibility changes |
| 98 | + const thresholdsArray = Array.from({ length: 101 }, (_, idx) => idx / 100); |
| 99 | + |
| 100 | + // Intersection Observer logic |
| 101 | + const intersectionCallback = (entries: IntersectionObserverEntry[]) => { |
| 102 | + entries.forEach((entry: IntersectionObserverEntry) => { |
| 103 | + if (entry.target.id) { |
| 104 | + visibilityMap[entry.target.id] = entry.intersectionRatio; |
| 105 | + } |
| 106 | + }); |
| 107 | + |
| 108 | + // Determine the most visible section |
| 109 | + const visibleSections = Object.entries(visibilityMap) |
| 110 | + .filter(([, ratio]: [string, number]) => ratio > 0) |
| 111 | + .sort((a: [string, number], b: [string, number]) => { |
| 112 | + // Primary: sections with >= 0.7 ratio first, secondary: vertical order |
| 113 | + const aHighVis = a[1] >= 0.7 ? 1 : 0; |
| 114 | + const bHighVis = b[1] >= 0.7 ? 1 : 0; |
| 115 | + if (bHighVis !== aHighVis) { |
| 116 | + return bHighVis - aHighVis; |
| 117 | + } |
| 118 | + |
| 119 | + // Secondary sort by vertical position |
| 120 | + const aElement = document.getElementById(a[0]); |
| 121 | + const bElement = document.getElementById(b[0]); |
| 122 | + if (aElement && bElement) { |
| 123 | + return aElement.offsetTop - bElement.offsetTop; |
| 124 | + } |
| 125 | + return 0; |
| 126 | + }); |
| 127 | + |
| 128 | + const newActiveSection = visibleSections.length ? visibleSections[0][0] : null; |
| 129 | + if (newActiveSection && newActiveSection !== currentActiveSection) { |
| 130 | + document.querySelectorAll('.sidebar-nav a.active').forEach(el => el.classList.remove('active')); |
| 131 | + document.querySelector(`.sidebar-nav a[data-section="${newActiveSection}"]`)?.classList.add('active'); |
| 132 | + currentActiveSection = newActiveSection; |
| 133 | + } |
| 134 | + }; |
| 135 | + |
| 136 | + const observerConfig: IntersectionObserverInit = { |
| 137 | + root: null, |
| 138 | + rootMargin: "0px 0px -30% 0px", |
| 139 | + threshold: thresholdsArray, |
| 140 | + }; |
| 141 | + |
| 142 | + const observer = new IntersectionObserver(intersectionCallback, observerConfig); |
| 143 | + |
| 144 | + // Observe sections |
| 145 | + const sectionsToObserve = document.querySelectorAll(".with-sidebar-nav section[id]"); |
| 146 | + sectionsToObserve.forEach((section) => { |
| 147 | + const sectionId = section.getAttribute("id"); |
| 148 | + if (sectionId) { |
| 149 | + visibilityMap[sectionId] = 0; |
| 150 | + observer.observe(section); |
| 151 | + } |
| 152 | + }); |
| 153 | + |
| 154 | + // Initial intersection calculation |
| 155 | + setTimeout(() => { |
| 156 | + intersectionCallback([]); |
| 157 | + }, 100); |
| 158 | + |
| 159 | + // Smooth-scroll event listener |
| 160 | + document.querySelectorAll(".sidebar-nav a").forEach((link) => { |
| 161 | + link.addEventListener("click", (e) => { |
| 162 | + e.preventDefault(); |
| 163 | + const targetId = link.getAttribute("href")?.substring(1); |
| 164 | + if (targetId) { |
| 165 | + const targetElement = document.getElementById(targetId); |
| 166 | + if (targetElement) { |
| 167 | + targetElement.scrollIntoView({ |
| 168 | + behavior: "smooth", |
| 169 | + block: "start", |
| 170 | + }); |
| 171 | + } |
| 172 | + } |
| 173 | + }); |
| 174 | + }); |
| 175 | + } |
| 176 | +</script> |
| 177 | + |
0 commit comments