Skip to content
Permalink
8d39b7cf6c
Switch branches/tags
Go to file
 
 
Cannot retrieve contributors at this time
122 lines (109 sloc) 3.8 KB
/*
* 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, OperatorFunction, combineLatest, pipe } from "rxjs"
import {
distinctUntilChanged,
filter,
map,
startWith,
switchMap,
zipWith
} from "rxjs/operators"
import {
Viewport,
getElement,
watchViewportAt
} from "browser"
import { useComponent } from "../../_"
import {
applyHeaderType,
watchHeader
} from "../react"
/* ----------------------------------------------------------------------------
* Types
* ------------------------------------------------------------------------- */
/**
* Header type
*/
export type HeaderType =
| "site" /* Header shows site title */
| "page" /* Header shows page title */
/* ------------------------------------------------------------------------- */
/**
* Header
*/
export interface Header {
type: HeaderType /* Header type */
sticky: boolean /* Header stickyness */
height: number /* Header visible height */
}
/* ----------------------------------------------------------------------------
* Helper types
* ------------------------------------------------------------------------- */
/**
* Mount options
*/
interface MountOptions {
document$: Observable<Document> /* Document observable */
viewport$: Observable<Viewport> /* Viewport observable */
}
/* ----------------------------------------------------------------------------
* Functions
* ------------------------------------------------------------------------- */
/**
* Mount header from source observable
*
* @param options - Options
*
* @return Operator function
*/
export function mountHeader(
{ document$, viewport$ }: MountOptions
): OperatorFunction<HTMLElement, Header> {
return pipe(
switchMap(el => {
const header$ = watchHeader(el, { document$ })
/* Compute whether the header should switch to page header */
const type$ = useComponent("main")
.pipe(
map(main => getElement("h1, h2, h3, h4, h5, h6", main)!),
filter(hx => typeof hx !== "undefined"),
zipWith(useComponent("header-title")),
switchMap(([hx, title]) => watchViewportAt(hx, { header$, viewport$ })
.pipe(
map(({ offset: { y } }) => {
return y >= hx.offsetHeight ? "page" : "site"
}),
distinctUntilChanged(),
applyHeaderType(title)
)
),
startWith<HeaderType>("site")
)
/* Combine into single observable */
return combineLatest([header$, type$])
.pipe(
map(([header, type]): Header => ({ type, ...header }))
)
})
)
}