目前阅读稳定版本，需要修改图片阅读方式

2026-05-23 15:50:53 +08:00
parent d7339aa255
commit 3e2669d8a8
7 changed files with 450 additions and 9 deletions
@@ -159,15 +159,43 @@ public final class RDEPUBTextBookBuilder {
            lastBuildResourceDiagnostics.append(contentsOf: rendered.resourceDiagnostics)

            let plainText = rendered.attributedString.string.trimmingCharacters(in: .whitespacesAndNewlines)
-            if shouldSkipChapter(item: item, text: plainText) {
+            if item.href.lowercased().contains("cover") {
+                print("[EPUB][Cover] rendered href=\(item.href) textLength=\(plainText.count) attrLength=\(rendered.attributedString.length) attachments=\(attachmentCount(in: rendered.attributedString))")
+            }
+            if shouldSkipChapter(item: item, content: rendered.attributedString, text: plainText) {
+                if item.href.lowercased().contains("cover") {
+                    print("[EPUB][Cover] skipped href=\(item.href)")
+                }
                continue
            }

            let chapterIndex = chapters.count
            let content = NSMutableAttributedString(attributedString: rendered.attributedString)
-            let layoutFrames = content.length > 0
-                ? content.rd_paginatedFrames(size: pageSize, fragmentOffsets: rendered.fragmentOffsets)
-                : []
+            let layoutFrames: [RDEPUBTextLayoutFrame]
+            if isAttachmentOnlyCoverChapter(item: item, content: content, plainText: plainText) {
+                layoutFrames = [
+                    RDEPUBTextLayoutFrame(
+                        contentRange: NSRange(location: 0, length: content.length),
+                        breakReason: .chapterEnd,
+                        blockRange: nil,
+                        attachmentRanges: attachmentRanges(in: content),
+                        attachmentKinds: [],
+                        blockKinds: [],
+                        semanticHints: [],
+                        attachmentPlacements: [],
+                        trailingFragmentID: nil,
+                        diagnostics: [
+                            "page break: chapterEnd",
+                            "cover fallback: single attachment page",
+                            "page range: \(NSStringFromRange(NSRange(location: 0, length: content.length)))"
+                        ]
+                    )
+                ]
+            } else {
+                layoutFrames = content.length > 0
+                    ? content.rd_paginatedFrames(size: pageSize, fragmentOffsets: rendered.fragmentOffsets)
+                    : []
+            }
            let effectiveFrames = layoutFrames.isEmpty && content.length > 0
                ? [
                    RDEPUBTextLayoutFrame(
@@ -187,6 +215,9 @@ public final class RDEPUBTextBookBuilder {
                    )
                ]
                : layoutFrames
+            if item.href.lowercased().contains("cover") {
+                print("[EPUB][Cover] paginated href=\(item.href) pages=\(effectiveFrames.count) firstRange=\(effectiveFrames.first.map { NSStringFromRange($0.contentRange) } ?? "none")")
+            }

            let pages = effectiveFrames.enumerated().map { localPageIndex, frame in
                let range = frame.contentRange
@@ -258,14 +289,55 @@ public final class RDEPUBTextBookBuilder {
        }
    }

-    private func shouldSkipChapter(item: RDEPUBSpineItem, text: String) -> Bool {
+    private func shouldSkipChapter(item: RDEPUBSpineItem, content: NSAttributedString, text: String) -> Bool {
        let lowercasedHref = item.href.lowercased()
-        if text.isEmpty && (lowercasedHref.contains("cover") || lowercasedHref.contains("title")) {
+        var hasAttachment = false
+        if content.length > 0 {
+            content.enumerateAttribute(.attachment, in: NSRange(location: 0, length: content.length)) { value, _, stop in
+                guard value != nil else { return }
+                hasAttachment = true
+                stop.pointee = true
+            }
+        }
+        if text.isEmpty && !hasAttachment && (lowercasedHref.contains("cover") || lowercasedHref.contains("title")) {
            return true
        }
        return false
    }

+    private func attachmentCount(in content: NSAttributedString) -> Int {
+        guard content.length > 0 else { return 0 }
+        var count = 0
+        content.enumerateAttribute(.attachment, in: NSRange(location: 0, length: content.length)) { value, _, _ in
+            if value != nil {
+                count += 1
+            }
+        }
+        return count
+    }
+
+    private func attachmentRanges(in content: NSAttributedString) -> [NSRange] {
+        guard content.length > 0 else { return [] }
+        var ranges: [NSRange] = []
+        content.enumerateAttribute(.attachment, in: NSRange(location: 0, length: content.length)) { value, range, _ in
+            if value != nil {
+                ranges.append(range)
+            }
+        }
+        return ranges
+    }
+
+    private func isAttachmentOnlyCoverChapter(
+        item: RDEPUBSpineItem,
+        content: NSAttributedString,
+        plainText: String
+    ) -> Bool {
+        let lowercasedHref = item.href.lowercased()
+        guard lowercasedHref.contains("cover") else { return false }
+        let trimmed = plainText.trimmingCharacters(in: .whitespacesAndNewlines)
+        return attachmentCount(in: content) > 0 && trimmed.count <= 1
+    }
+
    private func uniqueValues<T: Equatable>(from values: [T]) -> [T] {
        values.reduce(into: [T]()) { result, value in
            if !result.contains(value) {