LeadKit/Sources/Classes/DataLoading/PaginationDataLoading/PaginationDataLoadingModel....

93 lines
2.8 KiB
Swift

//
// Copyright (c) 2018 Touch Instinct
//
// 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 NONINFRINGEMENT. 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 RxSwift
/// Data loading model for PaginationDataLoadingState with ResettableRxDataSourceCursor as data source.
public final class PaginationDataLoadingModel<Cursor: ResettableRxDataSourceCursor>:
RxDataLoadingModel<PaginationDataLoadingState<Cursor>> {
private enum LoadType {
case reload
case retry
case next
}
override public func reload() {
load(.reload)
}
/// Attempt to load data again.
public func retry() {
load(.retry)
}
public func loadMore() {
load(.next)
}
private func load(_ loadType: LoadType) {
currentRequestDisposable?.dispose()
switch loadType {
case .reload, .retry:
replaceDataSource(with: dataSource.reset())
if loadType == .retry {
state = .initial
}
state = .initialLoading(after: state)
case .next:
if case .exhausted = state {
fatalError("You shouldn't call load(.next) after got .exhausted state!")
}
state = .loadingMore(after: state)
}
requestResult(from: dataSource)
}
override func onGot(error: Error) {
if case .exhausted? = error as? CursorError, case .initialLoading(let after) = state {
switch after {
case .initial, .empty: // cursor exhausted after creation
state = .empty
default:
super.onGot(error: error)
}
} else {
super.onGot(error: error)
}
}
override func updateStateAfterResult(from dataSource: DataSourceType) {
if dataSource.exhausted {
state = .exhausted
}
}
}