Added possibility to set viewport offset

src/assets/javascripts/observables/agent/viewport/_/index.ts

@@ -20,29 +20,23 @@
  * IN THE SOFTWARE.
  */
 
-import { Observable, combineLatest, fromEvent, merge } from "rxjs"
-import { map, shareReplay, startWith } from "rxjs/operators"
+import { Observable, combineLatest } from "rxjs"
+import { map, shareReplay } from "rxjs/operators"
+
+import { Header } from "../../../header"
+import {
+  ViewportOffset,
+  watchViewportOffset
+} from "../offset"
+import {
+  ViewportSize,
+  watchViewportSize
+} from "../size"
 
 /* ----------------------------------------------------------------------------
  * Types
  * ------------------------------------------------------------------------- */
 
-/**
- * Viewport offset
- */
-export interface ViewportOffset {
-  x: number                            /* Horizontal offset */
-  y: number                            /* Vertical offset */
-}
-
-/**
- * Viewport size
- */
-export interface ViewportSize {
-  width: number                        /* Viewport width */
-  height: number                       /* Viewport height */
-}
-
 /**
  * Viewport
  */
@@ -52,63 +46,20 @@ export interface Viewport {
 }
 
 /* ----------------------------------------------------------------------------
- * Functions
+ * Helper types
  * ------------------------------------------------------------------------- */
 
 /**
- * Retrieve viewport offset
- *
- * @return Viewport offset
+ * Watch relative options
  */
-export function getViewportOffset(): ViewportOffset {
-  return {
-    x: pageXOffset,
-    y: pageYOffset
-  }
+interface WatchRelativeOptions {
+  header$: Observable<Header>          /* Header observable */
+  viewport$: Observable<Viewport>      /* Viewport observable */
 }
 
-/**
- * Retrieve viewport size
- *
- * @return Viewport size
- */
-export function getViewportSize(): ViewportSize {
-  return {
-    width:  innerWidth,
-    height: innerHeight
-  }
-}
-
-/* ------------------------------------------------------------------------- */
-
-/**
- * Watch viewport offset
- *
- * @return Viewport offset observable
- */
-export function watchViewportOffset(): Observable<ViewportOffset> {
-  return merge(
-    fromEvent<UIEvent>(window, "scroll"),
-    fromEvent<UIEvent>(window, "resize")
-  )
-    .pipe(
-      map(getViewportOffset),
-      startWith(getViewportOffset())
-    )
-}
-
-/**
- * Watch viewport size
- *
- * @return Viewport size observable
- */
-export function watchViewportSize(): Observable<ViewportSize> {
-  return fromEvent<UIEvent>(window, "resize")
-    .pipe(
-      map(getViewportSize),
-      startWith(getViewportSize())
-    )
-}
+/* ----------------------------------------------------------------------------
+ * Functions
+ * ------------------------------------------------------------------------- */
 
 /**
  * Watch viewport
@@ -125,3 +76,27 @@ export function watchViewport(): Observable<Viewport> {
       shareReplay(1)
     )
 }
+
+/**
+ * Watch viewport relative to element
+ *
+ * @param el - Element
+ * @param options - Options
+ *
+ * @return Viewport observable
+ */
+export function watchViewportFrom(
+  el: HTMLElement, { header$, viewport$ }: WatchRelativeOptions
+): Observable<Viewport> {
+  return combineLatest([viewport$, header$])
+    .pipe(
+      map(([{ offset, size }, { height }]) => ({
+        offset: {
+          x: offset.x - el.offsetLeft,
+          y: offset.y - el.offsetTop + height
+        },
+        size
+      })),
+      shareReplay(1)
+    )
+}

src/assets/javascripts/observables/agent/viewport/index.ts

@@ -21,4 +21,5 @@
  */
 
 export * from "./_"
-export * from "./relative"
+export * from "./offset"
+export * from "./size"

src/assets/javascripts/observables/agent/viewport/offset/index.ts

@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2016-2020 Martin Donath <martin.donath@squidfunk.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+import { Observable, fromEvent, merge } from "rxjs"
+import { map, startWith } from "rxjs/operators"
+
+/* ----------------------------------------------------------------------------
+ * Types
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Viewport offset
+ */
+export interface ViewportOffset {
+  x: number                            /* Horizontal offset */
+  y: number                            /* Vertical offset */
+}
+
+/* ----------------------------------------------------------------------------
+ * Functions
+ * ------------------------------------------------------------------------- */
+
+/**
+ * Retrieve viewport offset
+ *
+ * @return Viewport offset
+ */
+export function getViewportOffset(): ViewportOffset {
+  return {
+    x: pageXOffset,
+    y: pageYOffset
+  }
+}
+
+/**
+ * Retrieve viewport offset
+ *
+ * @param offset - Viewport offset
+ */
+export function setViewportOffset(
+  { x, y }: Partial<ViewportOffset>
+): void {
+  window.scrollTo(x || 0, y || 0)
+}
+
+/* ------------------------------------------------------------------------- */
+
+/**
+ * Watch viewport offset
+ *
+ * @return Viewport offset observable
+ */
+export function watchViewportOffset(): Observable<ViewportOffset> {
+  return merge(
+    fromEvent<UIEvent>(window, "scroll"),
+    fromEvent<UIEvent>(window, "resize")
+  )
+    .pipe(
+      map(getViewportOffset),
+      startWith(getViewportOffset())
+    )
+}

src/assets/javascripts/observables/agent/viewport/size/index.ts

@@ -20,22 +20,19 @@
  * IN THE SOFTWARE.
  */
 
-import { Observable, combineLatest } from "rxjs"
-import { map, shareReplay } from "rxjs/operators"
-
-import { Header } from "../../../header"
-import { Viewport } from "../_"
+import { Observable, combineLatest, fromEvent, merge } from "rxjs"
+import { map, shareReplay, startWith } from "rxjs/operators"
 
 /* ----------------------------------------------------------------------------
- * Helper types
+ * Types
  * ------------------------------------------------------------------------- */
 
 /**
- * Watch options
+ * Viewport size
  */
-interface WatchOptions {
-  header$: Observable<Header>          /* Header observable */
-  viewport$: Observable<Viewport>      /* Viewport observable */
+export interface ViewportSize {
+  width: number                        /* Viewport width */
+  height: number                       /* Viewport height */
 }
 
 /* ----------------------------------------------------------------------------
@@ -43,25 +40,28 @@ interface WatchOptions {
  * ------------------------------------------------------------------------- */
 
 /**
- * Watch viewport relative to element
+ * Retrieve viewport size
  *
- * @param el - Element
- * @param options - Options
- *
- * @return Viewport observable
+ * @return Viewport size
  */
-export function watchViewportFrom(
-  el: HTMLElement, { header$, viewport$ }: WatchOptions
-): Observable<Viewport> {
-  return combineLatest([viewport$, header$])
+export function getViewportSize(): ViewportSize {
+  return {
+    width:  innerWidth,
+    height: innerHeight
+  }
+}
+
+/* ------------------------------------------------------------------------- */
+
+/**
+ * Watch viewport size
+ *
+ * @return Viewport size observable
+ */
+export function watchViewportSize(): Observable<ViewportSize> {
+  return fromEvent<UIEvent>(window, "resize")
     .pipe(
-      map(([{ offset, size }, { height }]) => ({
-        offset: {
-          x: offset.x - el.offsetLeft,
-          y: offset.y - el.offsetTop + height
-        },
-        size
-      })),
-      shareReplay(1)
+      map(getViewportSize),
+      startWith(getViewportSize())
     )
 }