import { debounceTime } from 'rxjs/operators'
import { ElementRef, OnDestroy, OnInit, ViewChild } from '@angular/core'
import { ActivatedRoute, Router } from '@angular/router'
import { Location } from '@angular/common'
import { InfiniteScrollerDirective } from '@app/shared/video/infinite-scroller.directive'
import { NotificationsService } from 'angular2-notifications'
import { fromEvent, Observable, Subscription } from 'rxjs'
import { AuthService } from '../../core/auth'
import { ComponentPagination } from '../rest/component-pagination.model'
import { VideoSortField } from './sort-field.type'
import { Video } from './video.model'
import { I18n } from '@ngx-translate/i18n-polyfill'
import { ScreenService } from '@app/shared/misc/screen.service'
import { OwnerDisplayType } from '@app/shared/video/video-miniature.component'
export abstract class AbstractVideoList implements OnInit, OnDestroy {
private static LINES_PER_PAGE = 4
@ViewChild('videosElement') videosElement: ElementRef
@ViewChild(InfiniteScrollerDirective) infiniteScroller: InfiniteScrollerDirective
pagination: ComponentPagination = {
currentPage: 1,
itemsPerPage: 10,
totalItems: null
}
sort: VideoSortField = '-publishedAt'
categoryOneOf?: number
defaultSort: VideoSortField = '-publishedAt'
syndicationItems = []
loadOnInit = true
marginContent = true
pageHeight: number
videoWidth: number
videoHeight: number
videoPages: Video[][] = []
ownerDisplayType: OwnerDisplayType = 'account'
firstLoadedPage: number
protected baseVideoWidth = 215
protected baseVideoHeight = 205
protected abstract notificationsService: NotificationsService
protected abstract authService: AuthService
protected abstract router: Router
protected abstract route: ActivatedRoute
protected abstract screenService: ScreenService
protected abstract i18n: I18n
protected abstract location: Location
protected abstract currentRoute: string
abstract titlePage: string
protected loadedPages: { [ id: number ]: Video[] } = {}
protected loadingPage: { [ id: number ]: boolean } = {}
protected otherRouteParams = {}
private resizeSubscription: Subscription
abstract getVideosObservable (page: number): Observable<{ videos: Video[], totalVideos: number}>
abstract generateSyndicationList ()
get user () {
return this.authService.getUser()
}
ngOnInit () {
// Subscribe to route changes
const routeParams = this.route.snapshot.queryParams
this.loadRouteParams(routeParams)
this.resizeSubscription = fromEvent(window, 'resize')
.pipe(debounceTime(500))
.subscribe(() => this.calcPageSizes())
this.calcPageSizes()
if (this.loadOnInit === true) this.loadMoreVideos(this.pagination.currentPage)
}
ngOnDestroy () {
if (this.resizeSubscription) this.resizeSubscription.unsubscribe()
}
onNearOfTop () {
this.previousPage()
}
onNearOfBottom () {
if (this.hasMoreVideos()) {
this.nextPage()
}
}
onPageChanged (page: number) {
this.pagination.currentPage = page
this.setNewRouteParams()
}
reloadVideos () {
this.loadedPages = {}
this.loadMoreVideos(this.pagination.currentPage)
}
loadMoreVideos (page: number, loadOnTop = false) {
this.adjustVideoPageHeight()
const currentY = window.scrollY
if (this.loadedPages[page] !== undefined) return
if (this.loadingPage[page] === true) return
this.loadingPage[page] = true
const observable = this.getVideosObservable(page)
observable.subscribe(
({ videos, totalVideos }) => {
this.loadingPage[page] = false
if (this.firstLoadedPage === undefined || this.firstLoadedPage > page) this.firstLoadedPage = page
// Paging is too high, return to the first one
if (this.pagination.currentPage > 1 && totalVideos <= ((this.pagination.currentPage - 1) * this.pagination.itemsPerPage)) {
this.pagination.currentPage = 1
this.setNewRouteParams()
return this.reloadVideos()
}
this.loadedPages[page] = videos
this.buildVideoPages()
this.pagination.totalItems = totalVideos
// Initialize infinite scroller now we loaded the first page
if (Object.keys(this.loadedPages).length === 1) {
// Wait elements creation
setTimeout(() => {
this.infiniteScroller.initialize()
// At our first load, we did not load the first page
// Load the previous page so the user can move on the top (and browser previous pages)
if (this.pagination.currentPage > 1) this.loadMoreVideos(this.pagination.currentPage - 1, true)
}, 500)
}
// Insert elements on the top but keep the scroll in the previous position
if (loadOnTop) setTimeout(() => { window.scrollTo(0, currentY + this.pageHeight) }, 0)
},
error => {
this.loadingPage[page] = false
this.notificationsService.error(this.i18n('Error'), error.message)
}
)
}
protected hasMoreVideos () {
// No results
if (this.pagination.totalItems === 0) return false
// Not loaded yet
if (!this.pagination.totalItems) return true
const maxPage = this.pagination.totalItems / this.pagination.itemsPerPage
return maxPage > this.maxPageLoaded()
}
protected previousPage () {
const min = this.minPageLoaded()
if (min > 1) {
this.loadMoreVideos(min - 1)
}
}
protected nextPage () {
this.loadMoreVideos(this.maxPageLoaded() + 1)
}
protected buildRouteParams () {
// There is always a sort and a current page
const params = {
sort: this.sort,
page: this.pagination.currentPage
}
return Object.assign(params, this.otherRouteParams)
}
protected loadRouteParams (routeParams: { [ key: string ]: any }) {
this.sort = routeParams['sort'] as VideoSortField || this.defaultSort
this.categoryOneOf = routeParams['categoryOneOf']
if (routeParams['page'] !== undefined) {
this.pagination.currentPage = parseInt(routeParams['page'], 10)
} else {
this.pagination.currentPage = 1
}
}
protected setNewRouteParams () {
const paramsObject = this.buildRouteParams()
const queryParams = Object.keys(paramsObject).map(p => p + '=' + paramsObject[p]).join('&')
this.location.replaceState(this.currentRoute, queryParams)
}
protected buildVideoPages () {
this.videoPages = Object.values(this.loadedPages)
}
protected adjustVideoPageHeight () {
const numberOfPagesLoaded = Object.keys(this.loadedPages).length
if (!numberOfPagesLoaded) return
this.pageHeight = this.videosElement.nativeElement.offsetHeight / numberOfPagesLoaded
}
protected buildVideoHeight () {
// Same ratios than base width/height
return this.videosElement.nativeElement.offsetWidth * (this.baseVideoHeight / this.baseVideoWidth)
}
private minPageLoaded () {
return Math.min(...Object.keys(this.loadedPages).map(e => parseInt(e, 10)))
}
private maxPageLoaded () {
return Math.max(...Object.keys(this.loadedPages).map(e => parseInt(e, 10)))
}
private calcPageSizes () {
if (this.screenService.isInMobileView() || this.baseVideoWidth === -1) {
this.pagination.itemsPerPage = 5
// Video takes all the width
this.videoWidth = -1
this.videoHeight = this.buildVideoHeight()
this.pageHeight = this.pagination.itemsPerPage * this.videoHeight
} else {
this.videoWidth = this.baseVideoWidth
this.videoHeight = this.baseVideoHeight
const videosWidth = this.videosElement.nativeElement.offsetWidth
this.pagination.itemsPerPage = Math.floor(videosWidth / this.videoWidth) * AbstractVideoList.LINES_PER_PAGE
this.pageHeight = this.videoHeight * AbstractVideoList.LINES_PER_PAGE
}
// Rebuild pages because maybe we modified the number of items per page
const videos = [].concat(...this.videoPages)
this.loadedPages = {}
let i = 1
// Don't include the last page if it not complete
while (videos.length >= this.pagination.itemsPerPage && i < 10000) { // 10000 -> Hard limit in case of infinite loop
this.loadedPages[i] = videos.splice(0, this.pagination.itemsPerPage)
i++
}
// Re fetch the last page
if (videos.length !== 0) {
this.loadMoreVideos(i)
} else {
this.buildVideoPages()
}
console.log('Rebuilt pages with %s elements per page.', this.pagination.itemsPerPage)
}
}