mirror of
https://github.com/squidfunk/mkdocs-material.git
synced 2024-06-14 11:52:32 +03:00
116 lines
3.7 KiB
TypeScript
116 lines
3.7 KiB
TypeScript
/*
|
|
* 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, combineLatest } from "rxjs"
|
|
import {
|
|
distinctUntilChanged,
|
|
map,
|
|
pluck,
|
|
shareReplay
|
|
} from "rxjs/operators"
|
|
|
|
import { Viewport } from "../../agent"
|
|
import { Header } from "../../header"
|
|
|
|
/* ----------------------------------------------------------------------------
|
|
* Types
|
|
* ------------------------------------------------------------------------- */
|
|
|
|
/**
|
|
* Main area
|
|
*/
|
|
export interface Main {
|
|
offset: number /* Main area top offset */
|
|
height: number /* Main area visible height */
|
|
active: boolean /* Scrolled past top offset */
|
|
}
|
|
|
|
/* ----------------------------------------------------------------------------
|
|
* Helper types
|
|
* ------------------------------------------------------------------------- */
|
|
|
|
/**
|
|
* Watch options
|
|
*/
|
|
interface WatchOptions {
|
|
header$: Observable<Header> /* Header observable */
|
|
viewport$: Observable<Viewport> /* Viewport observable */
|
|
}
|
|
|
|
/* ----------------------------------------------------------------------------
|
|
* Functions
|
|
* ------------------------------------------------------------------------- */
|
|
|
|
/**
|
|
* Watch main area
|
|
*
|
|
* This function returns an observable that computes the visual parameters of
|
|
* the main area which depends on the viewport vertical offset and height, as
|
|
* well as the height of the header element, if the header is fixed.
|
|
*
|
|
* @param el - Main area element
|
|
* @param options - Options
|
|
*
|
|
* @return Main area observable
|
|
*/
|
|
export function watchMain(
|
|
el: HTMLElement, { header$, viewport$ }: WatchOptions
|
|
): Observable<Main> {
|
|
|
|
/* Compute necessary adjustment for header */
|
|
const adjust$ = header$
|
|
.pipe(
|
|
pluck("height")
|
|
)
|
|
|
|
/* Compute the main area's visible height */
|
|
const height$ = combineLatest([viewport$, adjust$])
|
|
.pipe(
|
|
map(([{ offset: { y }, size: { height } }, adjust]) => {
|
|
const top = el.offsetTop
|
|
const bottom = el.offsetHeight + top
|
|
return height
|
|
- Math.max(0, top - y, adjust)
|
|
- Math.max(0, height + y - bottom)
|
|
}),
|
|
distinctUntilChanged()
|
|
)
|
|
|
|
/* Compute whether the viewport offset is past the main area's top */
|
|
const active$ = combineLatest([viewport$, adjust$])
|
|
.pipe(
|
|
map(([{ offset: { y } }, adjust]) => y >= el.offsetTop - adjust),
|
|
distinctUntilChanged()
|
|
)
|
|
|
|
/* Combine into a single hot observable */
|
|
return combineLatest([height$, adjust$, active$])
|
|
.pipe(
|
|
map(([height, adjust, active]) => ({
|
|
offset: el.offsetTop - adjust,
|
|
height,
|
|
active
|
|
})),
|
|
shareReplay(1)
|
|
)
|
|
}
|