Files
mkdocs-material/src/assets/javascripts/ui/viewport/_/index.ts
2019-10-27 10:26:54 +01:00

116 lines
3.4 KiB
TypeScript

/*
* Copyright (c) 2016-2019 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 { equals } from "ramda"
import { Observable, fromEvent, merge } from "rxjs"
import { distinctUntilChanged, map, startWith } from "rxjs/operators"
/* ----------------------------------------------------------------------------
* Data
* ------------------------------------------------------------------------- */
/**
* Observable for window scroll events
*/
const scroll$ = fromEvent<UIEvent>(window, "scroll")
/**
* Observable for window resize events
*/
const resize$ = fromEvent<UIEvent>(window, "resize")
/* ----------------------------------------------------------------------------
* 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 */
}
/* ----------------------------------------------------------------------------
* Functions
* ------------------------------------------------------------------------- */
/**
* Retrieve the viewport offset
*
* @return Viewport offset
*/
export function getViewportOffset(): ViewportOffset {
return {
x: window.pageXOffset,
y: window.pageYOffset
}
}
/**
* Retrieve the viewport size
*
* @return Viewport size
*/
export function getViewportSize(): ViewportSize {
return {
width: window.innerWidth,
height: window.innerHeight
}
}
/* ------------------------------------------------------------------------- */
/**
* Create an observable emitting changes in viewport offset
*
* @return Viewport offset observable
*/
export function fromViewportOffset(): Observable<ViewportOffset> {
return merge(scroll$, resize$).pipe(
map(getViewportOffset),
startWith(getViewportOffset()),
distinctUntilChanged<ViewportOffset>(equals)
)
}
/**
* Create an observable emitting changes in viewport size
*
* @return Viewport size observable
*/
export function fromViewportSize(): Observable<ViewportSize> {
return resize$.pipe(
map(getViewportSize),
startWith(getViewportSize()),
distinctUntilChanged<ViewportSize>(equals)
)
}