// Download the entire chapter
private Observable<Download> downloadChapter(Download download) {
try {
DiskUtils.createDirectory(download.directory);
} catch (IOException e) {
return Observable.error(e);
}
Observable<List<Page>> pageListObservable =
download.pages == null
?
// Pull page list from network and add them to download object
download
.source
.pullPageListFromNetwork(download.chapter.url)
.doOnNext(pages -> download.pages = pages)
.doOnNext(pages -> savePageList(download))
:
// Or if the page list already exists, start from the file
Observable.just(download.pages);
return pageListObservable
.subscribeOn(Schedulers.io())
.doOnNext(
pages -> {
download.downloadedImages = 0;
download.setStatus(Download.DOWNLOADING);
})
// Get all the URLs to the source images, fetch pages if necessary
.flatMap(download.source::getAllImageUrlsFromPageList)
// Start downloading images, consider we can have downloaded images already
.concatMap(page -> getOrDownloadImage(page, download))
// Do after download completes
.doOnCompleted(() -> onDownloadCompleted(download))
.toList()
.map(pages -> download)
// If the page list threw, it will resume here
.onErrorResumeNext(
error -> {
download.setStatus(Download.ERROR);
return Observable.just(download);
});
}
