ox-reveal update

scripts/reveal.js/js/controllers/location.js

@@ -3,6 +3,10 @@
  */
 export default class Location {
 
+	// The minimum number of milliseconds that must pass between
+	// calls to history.replaceState
+	MAX_REPLACE_STATE_FREQUENCY = 1000
+
 	constructor( Reveal ) {
 
 		this.Reveal = Reveal;
@@ -10,6 +14,8 @@ export default class Location {
 		// Delays updates to the URL due to a Chrome thumbnailer bug
 		this.writeURLTimeout = 0;
 
+		this.replaceStateTimestamp = 0;
+
 		this.onWindowHashChange = this.onWindowHashChange.bind( this );
 
 	}
@@ -27,19 +33,18 @@ export default class Location {
 	}
 
 	/**
-	 * Reads the current URL (hash) and navigates accordingly.
+	 * Returns the slide indices for the given hash link.
+	 *
+	 * @param {string} [hash] the hash string that we want to
+	 * find the indices for
+	 *
+	 * @returns slide indices or null
 	 */
-	readURL() {
-
-		let config = this.Reveal.getConfig();
-		let indices = this.Reveal.getIndices();
-		let currentSlide = this.Reveal.getCurrentSlide();
-
-		let hash = window.location.hash;
+	getIndicesFromHash( hash=window.location.hash ) {
 
 		// Attempt to parse the hash as either an index or name
-		let bits = hash.slice( 2 ).split( '/' ),
-			name = hash.replace( /#\/?/gi, '' );
+		let name = hash.replace( /^#\/?/, '' );
+		let bits = name.split( '/' );
 
 		// If the first bit is not fully numeric and there is a name we
 		// can assume that this is a named link
@@ -61,23 +66,12 @@ export default class Location {
 			}
 			catch ( error ) { }
 
-			// Ensure that we're not already on a slide with the same name
-			let isSameNameAsCurrentSlide = currentSlide ? currentSlide.getAttribute( 'id' ) === name : false;
-
 			if( element ) {
-				// If the slide exists and is not the current slide...
-				if ( !isSameNameAsCurrentSlide || typeof f !== 'undefined' ) {
-					// ...find the position of the named slide and navigate to it
-					let slideIndices = this.Reveal.getIndices( element );
-					this.Reveal.slide( slideIndices.h, slideIndices.v, f );
-				}
-			}
-			// If the slide doesn't exist, navigate to the current slide
-			else {
-				this.Reveal.slide( indices.h || 0, indices.v || 0 );
+				return { ...this.Reveal.getIndices( element ), f };
 			}
 		}
 		else {
+			const config = this.Reveal.getConfig();
 			let hashIndexBase = config.hashOneBasedIndex ? 1 : 0;
 
 			// Read the index components of the hash
@@ -92,10 +86,32 @@ export default class Location {
 				}
 			}
 
-			if( h !== indices.h || v !== indices.v || f !== undefined ) {
-				this.Reveal.slide( h, v, f );
+			return { h, v, f };
+		}
+
+		// The hash couldn't be parsed or no matching named link was found
+		return null
+
+	}
+
+	/**
+	 * Reads the current URL (hash) and navigates accordingly.
+	 */
+	readURL() {
+
+		const currentIndices = this.Reveal.getIndices();
+		const newIndices = this.getIndicesFromHash();
+
+		if( newIndices ) {
+			if( ( newIndices.h !== currentIndices.h || newIndices.v !== currentIndices.v || newIndices.f !== undefined ) ) {
+					this.Reveal.slide( newIndices.h, newIndices.v, newIndices.f );
 			}
 		}
+		// If no new indices are available, we're trying to navigate to
+		// a slide hash that does not exist
+		else {
+			this.Reveal.slide( currentIndices.h || 0, currentIndices.v || 0 );
+		}
 
 	}
 
@@ -132,10 +148,10 @@ export default class Location {
 			else if( config.hash ) {
 				// If the hash is empty, don't add it to the URL
 				if( hash === '/' ) {
-					window.history.replaceState( null, null, window.location.pathname + window.location.search );
+					this.debouncedReplaceState( window.location.pathname + window.location.search );
 				}
 				else {
-					window.history.replaceState( null, null, '#' + hash );
+					this.debouncedReplaceState( '#' + hash );
 				}
 			}
 			// UPDATE: The below nuking of all hash changes breaks
@@ -153,6 +169,26 @@ export default class Location {
 
 	}
 
+	replaceState( url ) {
+
+		window.history.replaceState( null, null, url );
+		this.replaceStateTimestamp = Date.now();
+
+	}
+
+	debouncedReplaceState( url ) {
+
+		clearTimeout( this.replaceStateTimeout );
+
+		if( Date.now() - this.replaceStateTimestamp > this.MAX_REPLACE_STATE_FREQUENCY ) {
+			this.replaceState( url );
+		}
+		else {
+			this.replaceStateTimeout = setTimeout( () => this.replaceState( url ), this.MAX_REPLACE_STATE_FREQUENCY );
+		}
+
+	}
+
 	/**
 	 * Return a hash URL that will resolve to the given slide location.
 	 *