Files
ReadViewSDK/Sources/RDReaderView/EPUBUI/ReaderController/RDEPUBReaderLocationCoordinator.swift
T

81 lines
3.3 KiB
Swift

import Foundation
/// EPUB 阅读器位置协调器:负责阅读位置的恢复、查询和持久化。
///
/// 职责:
/// - 根据保存的位置恢复阅读进度
/// - 获取当前可见页面的阅读位置
/// - 从持久化存储加载已保存位置
/// - 持久化当前位置并通知委托
final class RDEPUBReaderLocationCoordinator {
private unowned let context: RDEPUBReaderContext
init(context: RDEPUBReaderContext) {
self.context = context
}
/// 恢复到指定阅读位置,返回是否成功跳转。
@discardableResult
func restoreReadingLocation(_ location: RDEPUBLocation, animated: Bool = false) -> Bool {
guard let controller = context.controller,
let readerView = context.readerView else { return false }
guard let targetPageNumber = controller.pageNumber(for: location) else {
readerView.transitionToPage(pageNum: 0)
context.readingSession?.transition(to: .idle)
return false
}
if context.bookPageMap != nil {
guard context.runtime?.prepareOnDemandChapter(forAbsolutePageNumber: targetPageNumber) == true else {
return false
}
_ = context.readingSession?.queueNavigation(
to: location,
relativeToSpineIndex: nil,
bookIdentifier: context.currentBookIdentifier
)
} else if context.textBook == nil {
_ = context.readingSession?.queueNavigation(
to: location,
relativeToSpineIndex: nil,
bookIdentifier: context.currentBookIdentifier
)
} else {
context.readingSession?.transition(to: .jumping)
}
readerView.transitionToPage(pageNum: max(targetPageNumber - 1, 0), animated: animated)
return true
}
/// 获取当前可见页面对应的阅读位置。
func currentVisibleLocation() -> RDEPUBLocation? {
guard let controller = context.controller,
let readerView = context.readerView else {
return nil
}
if (context.textBook != nil || context.bookPageMap != nil), readerView.currentPage >= 0 {
return controller.resolvedTextLocation(forPageNumber: readerView.currentPage + 1)
}
return context.readingSession?.currentReadingLocation(bookIdentifier: context.currentBookIdentifier)
}
/// 从持久化存储加载上次保存的阅读位置。
func persistenceLocation() -> RDEPUBLocation? {
guard let controller = context.controller,
let currentBookIdentifier = context.currentBookIdentifier else {
return nil
}
return controller.persistence?.loadLocation(for: currentBookIdentifier)
}
/// 持久化阅读位置,并通知委托更新目录项和书签状态。
func persist(location: RDEPUBLocation) {
guard let controller = context.controller,
let currentBookIdentifier = context.currentBookIdentifier else { return }
controller.persistence?.saveLocation(location, for: currentBookIdentifier)
controller.delegate?.epubReader(controller, didUpdateLocation: location)
controller.delegate?.epubReader(controller, didUpdateCurrentTableOfContentsItem: controller.currentTableOfContentsItem)
controller.updateBookmarkChrome()
}
}