/// <summary>
/// Get the last page number of the tally. This may be determined solely
/// from the thread range info, or might require information from the
/// provided first page, where we can extract how many pages are in the thread.
/// </summary>
/// <param name="quest">The quest being tallied.</param>
/// <param name="adapter">The forum adapter that handles the quest's thread.</param>
/// <param name="threadRangeInfo">The range of posts that are wanted in the tally.</param>
/// <param name="firstPage">The first page of the tally, from which we can get the page range of the thread.</param>
/// <returns>Returns the last page number of the tally.</returns>
private async Task <int> GetLastPageNumber(IQuest quest, IForumAdapter2 adapter,
ThreadRangeInfo threadRangeInfo, Task <HtmlDocument?> firstPage)
{
// Check for quick results first.
if (threadRangeInfo.Pages > 0)
{
// If the page range has already been determined, use that.
return(threadRangeInfo.Pages);
}
if (!quest.ReadToEndOfThread && !threadRangeInfo.IsThreadmarkSearchResult)
{
// If we're not reading to the end of the thread, just calculate
// what the last page number will be. Pages to scan will be the
// difference in pages +1.
return(ThreadInfo.GetPageNumberOfPost(quest.EndPost, quest));
}
// If we're reading to the end of the thread (end post 0, or based on a threadmark),
// then we need to load the first page to find out how many pages there are in the thread.
var page = await firstPage.ConfigureAwait(false);
if (page == null)
{
throw new InvalidOperationException($"Unable to load first page of {quest.ThreadName}");
}
return(adapter.GetThreadInfo(page).Pages);
}
/// <summary>
/// Gets all posts from the provided pages list.
/// </summary>
/// <param name="loadingPages">The pages that are being loaded for the tally.</param>
/// <param name="quest">The quest being tallied.</param>
/// <param name="adapter">The forum adapter that handles the quest's thread.</param>
/// <returns>Returns all posts extracted from all pages provided,
/// and the thread title.</returns>
private async Task <(ThreadInfo threadInfo, List <Post> posts)> GetPostsFromPagesAsync(
List <Task <HtmlDocument?> > loadingPages,
IQuest quest, IForumAdapter2 adapter,
ThreadRangeInfo threadRangeInfo)
{
ThreadInfo? threadInfo = null;
List <Post> postsList = new List <Post>();
int pageNumber = threadRangeInfo.GetStartPage(quest) - 1;
bool incomplete = false;
foreach (var loadingPage in loadingPages)
{
var page = await loadingPage.ConfigureAwait(false);
pageNumber++;
if (page == null)
{
incomplete = true;
continue;
}
if (threadInfo == null)
{
threadInfo = adapter.GetThreadInfo(page);
}
postsList.AddRange(adapter.GetPosts(page, quest, pageNumber));
}
if (incomplete)
{
InvalidOperationException e = new InvalidOperationException("Unable to load all pages.");
e.Data["Application"] = true;
throw e;
}
if (threadInfo == null)
{
threadInfo = new ThreadInfo("Unknown", "Unknown", 0);
}
return(threadInfo, postsList);
}