refactor: split reader architecture and chrome handling

2026-05-31 21:47:54 +08:00
parent ea21c6a831
commit 44202357c0
80 changed files with 10635 additions and 8522 deletions
@@ -0,0 +1,222 @@
+import UIKit
+
+#if canImport(DTCoreText)
+import DTCoreText
+#endif
+
+// MARK: - 页面排版快照数据结构
+
+/// 文本行信息
+/// 描述 DTCoreText 排版后的一行文本的位置、范围和基线信息
+struct RDEPUBPageLine {
+    /// 行内文本在 chapterContent 中的绝对字符范围
+    let stringRange: NSRange
+    /// 行的框架（相对于排版区域）
+    let frame: CGRect
+    /// 行的基线原点
+    let baselineOrigin: CGPoint
+    /// 基线以上的高度（升部）
+    let ascent: CGFloat
+    /// 基线以下的高度（降部）
+    let descent: CGFloat
+    /// 行间距
+    let leading: CGFloat
+}
+
+/// 文本 Run 信息
+/// 描述一行内某个连续绘制单元（如普通文字或附件）
+struct RDEPUBPageRun {
+    /// Run 内文本的绝对字符范围
+    let stringRange: NSRange
+    /// Run 的绘制框架
+    let frame: CGRect
+    /// 是否为附件（图片等）
+    let isAttachment: Bool
+}
+
+/// 附件信息
+/// 描述嵌入在文本中的图片或其他附件
+struct RDEPUBPageAttachment {
+    /// 附件在文本中的绝对字符范围
+    let stringRange: NSRange
+    /// 附件的显示框架
+    let frame: CGRect
+    /// 附件的建议显示尺寸
+    let displaySize: CGSize
+    /// 附件的布局方式（行内/浮动等）
+    let placement: RDEPUBTextAttachmentPlacement?
+    /// 附件类型（封面图/普通图片等）
+    let kind: RDEPUBTextAttachmentKind?
+}
+
+// MARK: - 页面排版快照
+
+/// 页面排版快照
+/// 封装 DTCoreText 的排版结果，提供高效的文本位置查询能力
+/// 用于支持文本选择、高亮渲染和搜索结果定位
+struct RDEPUBPageLayoutSnapshot {
+    let page: RDEPUBTextPage
+    let lines: [RDEPUBPageLine]
+    let runs: [RDEPUBPageRun]
+    let attachments: [RDEPUBPageAttachment]
+    let pageContentRange: NSRange
+#if canImport(DTCoreText)
+    let layoutFrame: DTCoreTextLayoutFrame
+#endif
+
+    var contentBounds: CGRect {
+        let rects = lines.map(\.frame) + attachments.map(\.frame)
+        guard var bounds = rects.first else { return .zero }
+        for rect in rects.dropFirst() {
+            bounds = bounds.union(rect)
+        }
+        return bounds
+    }
+
+    func line(containing absoluteIndex: Int) -> RDEPUBPageLine? {
+        lines.first { NSLocationInRange(absoluteIndex, $0.stringRange) }
+    }
+
+    func run(containing absoluteIndex: Int) -> RDEPUBPageRun? {
+        runs.first { NSLocationInRange(absoluteIndex, $0.stringRange) }
+    }
+
+    func runs(intersecting range: NSRange) -> [RDEPUBPageRun] {
+        runs.filter { NSIntersectionRange($0.stringRange, range).length > 0 }
+    }
+
+    func attachment(at point: CGPoint, hitSlop: CGFloat = 6) -> RDEPUBPageAttachment? {
+        attachments.first { $0.frame.insetBy(dx: -hitSlop, dy: -hitSlop).contains(point) }
+    }
+
+    func line(at point: CGPoint, hitSlop: CGFloat = 4) -> RDEPUBPageLine? {
+        lines.first { line in
+            let lineRect = CGRect(
+                x: line.frame.minX,
+                y: line.baselineOrigin.y - line.ascent,
+                width: max(line.frame.width, 1),
+                height: line.ascent + line.descent + line.leading
+            )
+            return lineRect.insetBy(dx: -hitSlop, dy: -hitSlop).contains(point)
+        }
+    }
+
+    func run(at point: CGPoint, hitSlop: CGFloat = 4) -> RDEPUBPageRun? {
+        runs.first { $0.frame.insetBy(dx: -hitSlop, dy: -hitSlop).contains(point) }
+    }
+
+    func rects(containing point: CGPoint, in decorations: [RDEPUBTextOverlayDecoration]) -> [RDEPUBTextOverlayDecoration] {
+        decorations.filter { decoration in
+            decoration.rects.contains { $0.insetBy(dx: -4, dy: -4).contains(point) }
+        }
+    }
+
+    func absoluteRange(at point: CGPoint, in decorations: [RDEPUBTextOverlayDecoration]) -> NSRange? {
+        if let attachment = attachment(at: point) {
+            return attachment.stringRange
+        }
+        if let run = run(at: point) {
+            return run.stringRange
+        }
+        let hitDecorations = rects(containing: point, in: decorations)
+        if let mostSpecific = hitDecorations.min(by: { lhs, rhs in
+            lhs.absoluteRange.length < rhs.absoluteRange.length
+        }) {
+            return mostSpecific.absoluteRange
+        }
+        return line(at: point)?.stringRange
+    }
+
+#if canImport(DTCoreText)
+    static func build(
+        from layoutFrame: DTCoreTextLayoutFrame,
+        page: RDEPUBTextPage
+    ) -> RDEPUBPageLayoutSnapshot? {
+        guard let dtLines = layoutFrame.lines as? [DTCoreTextLayoutLine], !dtLines.isEmpty else {
+            return nil
+        }
+
+        var lines: [RDEPUBPageLine] = []
+        var runs: [RDEPUBPageRun] = []
+        var attachments: [RDEPUBPageAttachment] = []
+        let pageOffset = page.pageStartOffset
+
+        for dtLine in dtLines {
+            let lineRange = offset(dtLine.stringRange(), by: pageOffset)
+            let line = RDEPUBPageLine(
+                stringRange: lineRange,
+                frame: dtLine.frame,
+                baselineOrigin: dtLine.baselineOrigin,
+                ascent: dtLine.ascent,
+                descent: dtLine.descent,
+                leading: dtLine.leading
+            )
+            lines.append(line)
+
+            if let glyphRuns = dtLine.glyphRuns as? [DTCoreTextGlyphRun] {
+                for run in glyphRuns {
+                    let runRange = offset(run.stringRange(), by: pageOffset)
+                    let isAttachment = run.attachment != nil
+                    runs.append(
+                        RDEPUBPageRun(
+                            stringRange: runRange,
+                            frame: run.frame,
+                            isAttachment: isAttachment
+                        )
+                    )
+
+                    guard isAttachment else { continue }
+                    let metadata = attachmentMetadata(
+                        for: runRange,
+                        on: page
+                    )
+                    attachments.append(
+                        RDEPUBPageAttachment(
+                            stringRange: runRange,
+                            frame: run.frame,
+                            displaySize: run.frame.size,
+                            placement: metadata.placement,
+                            kind: metadata.kind
+                        )
+                    )
+                }
+            }
+        }
+
+        let visibleRange = offset(layoutFrame.visibleStringRange(), by: pageOffset)
+
+        return RDEPUBPageLayoutSnapshot(
+            page: page,
+            lines: lines,
+            runs: runs,
+            attachments: attachments,
+            pageContentRange: visibleRange,
+            layoutFrame: layoutFrame
+        )
+    }
+
+    private static func attachmentMetadata(
+        for range: NSRange,
+        on page: RDEPUBTextPage
+    ) -> (placement: RDEPUBTextAttachmentPlacement?, kind: RDEPUBTextAttachmentKind?) {
+        guard let attachmentIndex = page.metadata.attachmentRanges.firstIndex(where: { NSIntersectionRange($0, range).length > 0 }) else {
+            return (nil, nil)
+        }
+
+        let placement = page.metadata.attachmentPlacements.indices.contains(attachmentIndex)
+            ? page.metadata.attachmentPlacements[attachmentIndex]
+            : nil
+        let kind = page.metadata.attachmentKinds.indices.contains(attachmentIndex)
+            ? page.metadata.attachmentKinds[attachmentIndex]
+            : nil
+        return (placement, kind)
+    }
+
+    private static func offset(_ range: NSRange, by offset: Int) -> NSRange {
+        guard range.location != NSNotFound else {
+            return range
+        }
+        return NSRange(location: range.location + offset, length: range.length)
+    }
+#endif
+}