introducing: minimal mistakes

assets/js/plugins/gumshoe.js

@@ -0,0 +1,482 @@
+/*!
+ * gumshoejs v5.1.0
+ * A simple, framework-agnostic scrollspy script.
+ * (c) 2019 Chris Ferdinandi
+ * MIT License
+ * http://github.com/cferdinandi/gumshoe
+ */
+
+(function (root, factory) {
+	if ( typeof define === 'function' && define.amd ) {
+		define([], (function () {
+			return factory(root);
+		}));
+	} else if ( typeof exports === 'object' ) {
+		module.exports = factory(root);
+	} else {
+		root.Gumshoe = factory(root);
+	}
+})(typeof global !== 'undefined' ? global : typeof window !== 'undefined' ? window : this, (function (window) {
+
+	'use strict';
+
+	//
+	// Defaults
+	//
+
+	var defaults = {
+
+		// Active classes
+		navClass: 'active',
+		contentClass: 'active',
+
+		// Nested navigation
+		nested: false,
+		nestedClass: 'active',
+
+		// Offset & reflow
+		offset: 0,
+		reflow: false,
+
+		// Event support
+		events: true
+
+	};
+
+
+	//
+	// Methods
+	//
+
+	/**
+	 * Merge two or more objects together.
+	 * @param   {Object}   objects  The objects to merge together
+	 * @returns {Object}            Merged values of defaults and options
+	 */
+	var extend = function () {
+		var merged = {};
+		Array.prototype.forEach.call(arguments, (function (obj) {
+			for (var key in obj) {
+				if (!obj.hasOwnProperty(key)) return;
+				merged[key] = obj[key];
+			}
+		}));
+		return merged;
+	};
+
+	/**
+	 * Emit a custom event
+	 * @param  {String} type   The event type
+	 * @param  {Node}   elem   The element to attach the event to
+	 * @param  {Object} detail Any details to pass along with the event
+	 */
+	var emitEvent = function (type, elem, detail) {
+
+		// Make sure events are enabled
+		if (!detail.settings.events) return;
+
+		// Create a new event
+		var event = new CustomEvent(type, {
+			bubbles: true,
+			cancelable: true,
+			detail: detail
+		});
+
+		// Dispatch the event
+		elem.dispatchEvent(event);
+
+	};
+
+	/**
+	 * Get an element's distance from the top of the Document.
+	 * @param  {Node} elem The element
+	 * @return {Number}    Distance from the top in pixels
+	 */
+	var getOffsetTop = function (elem) {
+		var location = 0;
+		if (elem.offsetParent) {
+			while (elem) {
+				location += elem.offsetTop;
+				elem = elem.offsetParent;
+			}
+		}
+		return location >= 0 ? location : 0;
+	};
+
+	/**
+	 * Sort content from first to last in the DOM
+	 * @param  {Array} contents The content areas
+	 */
+	var sortContents = function (contents) {
+		contents.sort((function (item1, item2) {
+			var offset1 = getOffsetTop(item1.content);
+			var offset2 = getOffsetTop(item2.content);
+			if (offset1 < offset2) return -1;
+			return 1;
+		}));
+	};
+
+	/**
+	 * Get the offset to use for calculating position
+	 * @param  {Object} settings The settings for this instantiation
+	 * @return {Float}           The number of pixels to offset the calculations
+	 */
+	var getOffset = function (settings) {
+
+		// if the offset is a function run it
+		if (typeof settings.offset === 'function') {
+			return parseFloat(settings.offset());
+		}
+
+		// Otherwise, return it as-is
+		return parseFloat(settings.offset);
+
+	};
+
+	/**
+	 * Get the document element's height
+	 * @private
+	 * @returns {Number}
+	 */
+	var getDocumentHeight = function () {
+		return Math.max(
+			document.body.scrollHeight, document.documentElement.scrollHeight,
+			document.body.offsetHeight, document.documentElement.offsetHeight,
+			document.body.clientHeight, document.documentElement.clientHeight
+		);
+	};
+
+	/**
+	 * Determine if an element is in view
+	 * @param  {Node}    elem     The element
+	 * @param  {Object}  settings The settings for this instantiation
+	 * @param  {Boolean} bottom   If true, check if element is above bottom of viewport instead
+	 * @return {Boolean}          Returns true if element is in the viewport
+	 */
+	var isInView = function (elem, settings, bottom) {
+		var bounds = elem.getBoundingClientRect();
+		var offset = getOffset(settings);
+		if (bottom) {
+			return parseInt(bounds.bottom, 10) < (window.innerHeight || document.documentElement.clientHeight);
+		}
+		return parseInt(bounds.top, 10) <= offset;
+	};
+
+	/**
+	 * Check if at the bottom of the viewport
+	 * @return {Boolean} If true, page is at the bottom of the viewport
+	 */
+	var isAtBottom = function () {
+		if (window.innerHeight + window.pageYOffset >= getDocumentHeight()) return true;
+		return false;
+	};
+
+	/**
+	 * Check if the last item should be used (even if not at the top of the page)
+	 * @param  {Object} item     The last item
+	 * @param  {Object} settings The settings for this instantiation
+	 * @return {Boolean}         If true, use the last item
+	 */
+	var useLastItem = function (item, settings) {
+		if (isAtBottom() && isInView(item.content, settings, true)) return true;
+		return false;
+	};
+
+	/**
+	 * Get the active content
+	 * @param  {Array}  contents The content areas
+	 * @param  {Object} settings The settings for this instantiation
+	 * @return {Object}          The content area and matching navigation link
+	 */
+	var getActive = function (contents, settings) {
+		var last = contents[contents.length-1];
+		if (useLastItem(last, settings)) return last;
+		for (var i = contents.length - 1; i >= 0; i--) {
+			if (isInView(contents[i].content, settings)) return contents[i];
+		}
+	};
+
+	/**
+	 * Deactivate parent navs in a nested navigation
+	 * @param  {Node}   nav      The starting navigation element
+	 * @param  {Object} settings The settings for this instantiation
+	 */
+	var deactivateNested = function (nav, settings) {
+
+		// If nesting isn't activated, bail
+		if (!settings.nested) return;
+
+		// Get the parent navigation
+		var li = nav.parentNode.closest('li');
+		if (!li) return;
+
+		// Remove the active class
+		li.classList.remove(settings.nestedClass);
+
+		// Apply recursively to any parent navigation elements
+		deactivateNested(li, settings);
+
+	};
+
+	/**
+	 * Deactivate a nav and content area
+	 * @param  {Object} items    The nav item and content to deactivate
+	 * @param  {Object} settings The settings for this instantiation
+	 */
+	var deactivate = function (items, settings) {
+
+		// Make sure their are items to deactivate
+		if (!items) return;
+
+		// Get the parent list item
+		var li = items.nav.closest('li');
+		if (!li) return;
+
+		// Remove the active class from the nav and content
+		li.classList.remove(settings.navClass);
+		items.content.classList.remove(settings.contentClass);
+
+		// Deactivate any parent navs in a nested navigation
+		deactivateNested(li, settings);
+
+		// Emit a custom event
+		emitEvent('gumshoeDeactivate', li, {
+			link: items.nav,
+			content: items.content,
+			settings: settings
+		});
+
+	};
+
+
+	/**
+	 * Activate parent navs in a nested navigation
+	 * @param  {Node}   nav      The starting navigation element
+	 * @param  {Object} settings The settings for this instantiation
+	 */
+	var activateNested = function (nav, settings) {
+
+		// If nesting isn't activated, bail
+		if (!settings.nested) return;
+
+		// Get the parent navigation
+		var li = nav.parentNode.closest('li');
+		if (!li) return;
+
+		// Add the active class
+		li.classList.add(settings.nestedClass);
+
+		// Apply recursively to any parent navigation elements
+		activateNested(li, settings);
+
+	};
+
+	/**
+	 * Activate a nav and content area
+	 * @param  {Object} items    The nav item and content to activate
+	 * @param  {Object} settings The settings for this instantiation
+	 */
+	var activate = function (items, settings) {
+
+		// Make sure their are items to activate
+		if (!items) return;
+
+		// Get the parent list item
+		var li = items.nav.closest('li');
+		if (!li) return;
+
+		// Add the active class to the nav and content
+		li.classList.add(settings.navClass);
+		items.content.classList.add(settings.contentClass);
+
+		// Activate any parent navs in a nested navigation
+		activateNested(li, settings);
+
+		// Emit a custom event
+		emitEvent('gumshoeActivate', li, {
+			link: items.nav,
+			content: items.content,
+			settings: settings
+		});
+
+	};
+
+	/**
+	 * Create the Constructor object
+	 * @param {String} selector The selector to use for navigation items
+	 * @param {Object} options  User options and settings
+	 */
+	var Constructor = function (selector, options) {
+
+		//
+		// Variables
+		//
+
+		var publicAPIs = {};
+		var navItems, contents, current, timeout, settings;
+
+
+		//
+		// Methods
+		//
+
+		/**
+		 * Set variables from DOM elements
+		 */
+		publicAPIs.setup = function () {
+
+			// Get all nav items
+			navItems = document.querySelectorAll(selector);
+
+			// Create contents array
+			contents = [];
+
+			// Loop through each item, get it's matching content, and push to the array
+			Array.prototype.forEach.call(navItems, (function (item) {
+
+				// Get the content for the nav item
+				var content = document.getElementById(decodeURIComponent(item.hash.substr(1)));
+				if (!content) return;
+
+				// Push to the contents array
+				contents.push({
+					nav: item,
+					content: content
+				});
+
+			}));
+
+			// Sort contents by the order they appear in the DOM
+			sortContents(contents);
+
+		};
+
+		/**
+		 * Detect which content is currently active
+		 */
+		publicAPIs.detect = function () {
+
+			// Get the active content
+			var active = getActive(contents, settings);
+
+			// if there's no active content, deactivate and bail
+			if (!active) {
+				if (current) {
+					deactivate(current, settings);
+					current = null;
+				}
+				return;
+			}
+
+			// If the active content is the one currently active, do nothing
+			if (current && active.content === current.content) return;
+
+			// Deactivate the current content and activate the new content
+			deactivate(current, settings);
+			activate(active, settings);
+
+			// Update the currently active content
+			current = active;
+
+		};
+
+		/**
+		 * Detect the active content on scroll
+		 * Debounced for performance
+		 */
+		var scrollHandler = function (event) {
+
+			// If there's a timer, cancel it
+			if (timeout) {
+				window.cancelAnimationFrame(timeout);
+			}
+
+			// Setup debounce callback
+			timeout = window.requestAnimationFrame(publicAPIs.detect);
+
+		};
+
+		/**
+		 * Update content sorting on resize
+		 * Debounced for performance
+		 */
+		var resizeHandler = function (event) {
+
+			// If there's a timer, cancel it
+			if (timeout) {
+				window.cancelAnimationFrame(timeout);
+			}
+
+			// Setup debounce callback
+			timeout = window.requestAnimationFrame((function () {
+				sortContents();
+				publicAPIs.detect();
+			}));
+
+		};
+
+		/**
+		 * Destroy the current instantiation
+		 */
+		publicAPIs.destroy = function () {
+
+			// Undo DOM changes
+			if (current) {
+				deactivate(current);
+			}
+
+			// Remove event listeners
+			window.removeEventListener('scroll', scrollHandler, false);
+			if (settings.reflow) {
+				window.removeEventListener('resize', resizeHandler, false);
+			}
+
+			// Reset variables
+			contents = null;
+			navItems = null;
+			current = null;
+			timeout = null;
+			settings = null;
+
+		};
+
+		/**
+		 * Initialize the current instantiation
+		 */
+		var init = function () {
+
+			// Merge user options into defaults
+			settings = extend(defaults, options || {});
+
+			// Setup variables based on the current DOM
+			publicAPIs.setup();
+
+			// Find the currently active content
+			publicAPIs.detect();
+
+			// Setup event listeners
+			window.addEventListener('scroll', scrollHandler, false);
+			if (settings.reflow) {
+				window.addEventListener('resize', resizeHandler, false);
+			}
+
+		};
+
+
+		//
+		// Initialize and return the public APIs
+		//
+
+		init();
+		return publicAPIs;
+
+	};
+
+
+	//
+	// Return the Constructor
+	//
+
+	return Constructor;
+
+}));