486 lines
26 KiB
Markdown
486 lines
26 KiB
Markdown
# Phase 8: 分页质量、缓存与性能采样 - Research
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**Researched:** 2026-05-23
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**Domain:** iOS/Swift EPUB reader - pagination caching, quality improvement, performance sampling
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**Confidence:** HIGH
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## Summary
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Phase 8 builds on Phase 6 (page geometry) and Phase 7 (custom attribute closure) to address three concerns: pagination caching, pagination quality for complex image-heavy chapters, and performance diagnostics.
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**Critical finding:** Several capabilities assumed to be "not yet integrated" in CONTEXT.md and ARCHITECTURE-CONTEXT.md are actually already implemented:
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- `RDEPUBTextBookBuilder.build()` already calls `content.rd_paginatedFrames(size:)` (not `ss_pageRanges`). The integration is DONE.
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- CSS `<link>` inlining is already implemented via `inlineLinkedStyleSheets()` in `RDEPUBTextRendererSupport`.
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- The 5-layer CSS cascade is already implemented via `makeStyleSheetLayers()` producing `RDEPUBTextStyleSheetPackage` layers.
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- `RDEPUBTextPage.metadata` is already populated with `RDEPUBTextPageMetadata` from `frame.metadata`.
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**What actually needs building:**
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1. **Pagination cache** (QUAL-01): Serialize `RDEPUBTextBook` to disk, keyed by layout parameters
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2. **Image/attachment rules** (QUAL-03): Formalize sizing, dark mode, and page-break-around-image rules
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3. **Performance sampling** (QUAL-04): Instrument render/paginate/build timings
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4. **Pagination quality** (QUAL-02): Implement `avoidPageBreakInside` line-removal, orphan/widow control, image fit enforcement
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**Primary recommendation:** Focus Phase 8 on cache serialization (the largest new code), performance instrumentation (straightforward), and incremental pagination quality improvements. Do NOT re-implement CSS `<link>` inlining or 5-layer cascade -- they already work.
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## Architectural Responsibility Map
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| Capability | Primary Tier | Secondary Tier | Rationale |
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|------------|-------------|----------------|-----------|
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| Pagination cache storage | API / Backend (file system) | -- | Cache is local disk persistence, no UI involvement |
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| Cache key generation | API / Backend | -- | Pure computation from layout parameters |
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| Performance timing | API / Backend | -- | CFAbsoluteTimeGetCurrent at build/render points |
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| Image sizing rules | API / Backend (renderer) | Browser/Client (display) | Rules applied during DTCoreText rendering |
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| avoidPageBreakInside enforcement | API / Backend (layouter) | -- | CoreText line-level calculation |
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| Orphan/widow control | API / Backend (layouter) | -- | CoreText line-level calculation |
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| Pagination diagnostic output | API / Backend | Browser/Client (logging) | Diagnostic data flows to console/log |
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## User Constraints (from CONTEXT.md)
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### Locked Decisions
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- **D-01 [P0]:** Integrate `RDEPUBTextLayouter` into `RDEPUBTextBookBuilder` -- ALREADY DONE (see finding above)
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- **D-02 [P0]:** Expose `metadata: RDEPUBTextPageMetadata` on `RDEPUBTextPage` -- ALREADY DONE
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- **D-03 [P0]:** Pagination cache by `bookID + fontSize + lineHeightMultiple + contentInsets`, cache full `RDEPUBTextBook` to disk
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- **D-04 [P0]:** CSS `<link>` inline processing -- ALREADY DONE
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- **D-05 [P0]:** 5-layer CSS cascade -- ALREADY DONE
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- **D-06 [P1]:** Image/attachment processing rules with diagnostics
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- **D-07 [P1]:** Performance sampling -- output stable sampling data
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### Claude's Discretion
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- Cache storage format (file system plist/JSON vs SQLite) -- implementer decides
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- CSS cascade replace.css content -- reference WXRead but don't copy exactly
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- Performance sampling threshold values -- determine at implementation time
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### Deferred Ideas (OUT OF SCOPE)
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- CoreText direct drawing migration (v1.2/v2.0)
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- Font system (embedded font set, future version)
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- Character-level position precision (P2)
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- Chapter data model cohesion (P2)
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- TTS / DRM / Pencil / multi-column layout (P3)
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<phase_requirements>
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## Phase Requirements
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| ID | Description | Research Support |
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|----|-------------|------------------|
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| QUAL-01 | Cache mechanism for layout frames/pagination results to avoid redundant full-layout | Cache key design from WXRead `WRChapterPageCount.currentCacheKeyWithBookId:`, serialization strategy for `RDEPUBTextBook` |
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| QUAL-02 | Improve pagination quality for complex image-heavy chapters -- reduce bad breaks, orphan/widow lines, image whitespace issues, code/table truncation | WXRead `avoidPageBreakInsideByRemovingLastLinesIfNeeded` pattern, `WRCoreTextLayoutConfig` widow/orphan settings |
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| QUAL-03 | Image/attachment sizing rules, dark mode adaptation, page background info with verifiable rules | WXRead `wr-vertical-center-style`, `DTPageBreakInsideAvoid`, existing `prepareHTMLElementForReaderRendering` |
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| QUAL-04 | No significant degradation of first-screen time, repagination time, or interaction fluidity; output stable diagnostic/sampling data | Performance sampling points at render/paginate/build, `CFAbsoluteTimeGetCurrent` pattern |
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</phase_requirements>
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## Standard Stack
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### Core (no new external dependencies)
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This phase uses only existing project dependencies and Apple frameworks:
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| Library | Version | Purpose | Why Standard |
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|---------|---------|---------|--------------|
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| Foundation | iOS SDK | NSKeyedArchiver, JSONEncoder, FileManager | System framework, no alternative |
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| CoreText | iOS SDK | CTFramesetter, CTFrame line inspection | Already used by RDEPUBTextLayouter |
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| DTCoreText | (existing) | HTML-to-NSAttributedString | Already integrated |
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| CryptoKit / CommonCrypto | iOS SDK | SHA256 for cache key hashing | System framework |
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### Supporting
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| Library | Version | Purpose | When to Use |
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|---------|---------|---------|-------------|
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| os.signpost | iOS 15+ | Performance instrumentation with Instruments integration | If structured performance logging desired |
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### Alternatives Considered
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| Instead of | Could Use | Tradeoff |
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|------------|-----------|----------|
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| NSKeyedArchiver for cache | JSONEncoder | JSON is human-readable but can't handle NSAttributedString natively; NSKeyedArchiver handles it but produces opaque binary |
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| File system cache | SQLite | File system is simpler for whole-object caching; SQLite adds complexity for no gain when caching complete objects |
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| SHA256 cache key | Simple string concatenation | SHA256 produces fixed-length keys safe for filenames; raw string could exceed filesystem limits |
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**Installation:** No new packages needed.
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## Package Legitimacy Audit
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No external packages are installed in this phase. All dependencies are existing project dependencies or Apple system frameworks.
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| Package | Registry | Age | Downloads | Source Repo | slopcheck | Disposition |
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|---------|----------|-----|-----------|-------------|-----------|-------------|
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| (none) | -- | -- | -- | -- | -- | N/A |
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## Architecture Patterns
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### Current Data Flow (already working)
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```
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RDEPUBReaderController.paginate(restoreLocation:)
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-> RDEPUBTextBookBuilder.build(parser:publication:pageSize:style:)
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-> for each spine item:
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-> RDEPUBTextRendererSupport.makeChapterRenderRequest(...)
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-> inlineLinkedStyleSheets() [CSS <link> inlining - DONE]
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-> makeStyleSheetLayers() [5-layer cascade - DONE]
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-> injectPaginationSemanticMarkers() [semantic markers - DONE]
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-> renderer.renderChapter(request:) [DTCoreText render]
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-> content.rd_paginatedFrames(size:) [4-level semantic pagination - DONE]
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-> RDEPUBTextPage with metadata [metadata exposure - DONE]
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-> RDEPUBTextBook(chapters:, pages:)
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-> applyTextBook(restoreLocation:)
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```
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### Recommended Cache Integration Point
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```
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RDEPUBReaderController.paginate(restoreLocation:)
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-> compute cacheKey from bookID + layout params
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-> if cached RDEPUBTextBook exists for key:
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-> applyTextBook(cachedBook, restoreLocation:) [CACHE HIT - skip build]
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-> else:
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-> builder.build(...) [existing flow]
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-> save RDEPUBTextBook to cache [CACHE WRITE]
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-> applyTextBook(textBook, restoreLocation:)
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```
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### Recommended Project Structure
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```
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Sources/RDReaderView/EPUBTextRendering/
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├── RDEPUBTextBookBuilder.swift # existing - add cache integration
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├── RDEPUBTextBookCache.swift # NEW - cache key, read/write, eviction
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├── RDEPUBTextLayouter.swift # existing - add avoidPageBreakInside enforcement
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├── RDEPUBTextLayoutFrame.swift # existing - no changes needed
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├── RDEPUBTextPaginationSupport.swift # existing - no changes needed
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├── RDEPUBTextRenderer.swift # existing - no changes needed
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├── RDEPUBTextRendererSupport.swift # existing - add image rule formalization
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├── RDEPUBDTCoreTextRenderer.swift # existing - no changes needed
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├── RDEPUBTextPerformanceSampler.swift # NEW - timing instrumentation
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└── RDPlainTextBookBuilder.swift # existing - no changes needed
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```
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### Pattern 1: Cache Key Generation
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**What:** Generate a deterministic cache key from layout parameters that change pagination results.
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**When to use:** Before every `builder.build()` call.
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**Example:**
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```swift
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// Reference: WXRead WRChapterPageCount.currentCacheKeyWithBookId:
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// WXRead encodes: bookId + fontSize + lineSpacing + pageWidth + pageHeight
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struct RDEPUBTextBookCacheKey {
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let bookID: String
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let fontSize: CGFloat
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let lineHeightMultiple: CGFloat
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let contentInsets: UIEdgeInsets
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let pageSize: CGSize
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var stringValue: String {
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let raw = "\(bookID)|\(fontSize)|\(lineHeightMultiple)|\(contentInsets.top)|\(contentInsets.left)|\(contentInsets.bottom)|\(contentInsets.right)|\(pageSize.width)|\(pageSize.height)"
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// SHA256 for safe filename
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let data = Data(raw.utf8)
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let hash = SHA256.hash(data: data)
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return hash.map { String(format: "%02x", $0) }.joined()
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}
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}
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```
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**Source:** [VERIFIED: Doc/WXRead/decompiled/WRChapterPageCount.m lines 64-90]
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### Pattern 2: avoidPageBreakInside Line Removal
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**What:** When a block marked `avoidPageBreakInside` would cross a page boundary, remove trailing lines from the current page to push the entire block to the next page.
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**When to use:** During `RDEPUBTextLayouter.adjustedRange()` after the 4-level semantic break detection.
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**Example:**
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```swift
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// Reference: WXRead WRCoreTextLayoutFrame.avoidPageBreakInsideByRemovingLastLinesIfNeeded
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// If the proposed page end falls inside an avoidPageBreakInside block:
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// 1. Find the block's start location
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// 2. If block start >= minimumEnd, break at block start
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// 3. If block start < minimumEnd (block is too large), fall through to frameLimit
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```
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**Source:** [VERIFIED: Doc/WXRead/decompiled/WRCoreTextLayoutFrame.h line 280]
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### Pattern 3: Performance Sampling
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**What:** Measure wall-clock time for render, paginate, and full-build operations.
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**When to use:** At the entry/exit of `builder.build()`, `renderer.renderChapter()`, and `content.rd_paginatedFrames()`.
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**Example:**
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```swift
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struct RDEPUBTextPerformanceSample {
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var chapterHref: String
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var renderDuration: TimeInterval // DTHTMLAttributedStringBuilder
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var paginateDuration: TimeInterval // CTFramesetter pagination
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var totalDuration: TimeInterval // end-to-end
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var attributedStringLength: Int
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var pageCount: Int
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var cacheHit: Bool
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}
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// Measurement pattern:
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let start = CFAbsoluteTimeGetCurrent()
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// ... operation ...
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let duration = CFAbsoluteTimeGetCurrent() - start
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```
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**Source:** [ASSUMED] -- standard iOS performance measurement pattern
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### Anti-Patterns to Avoid
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- **Storing NSAttributedString via JSONEncoder:** NSAttributedString is not Codable. Use NSKeyedArchiver or store the raw HTML + re-render parameters instead.
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- **Cache key that includes theme colors:** Theme (dark/light) changes CSS output but the pagination structure (NSRanges) is the same for the same font/size/insets. However, the attributed string content differs. Cache should store the full RDEPUBTextBook including styled content, so theme must be part of the key OR cache should store structure only and re-render content.
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- **Measuring on main thread:** All build/paginate work happens on `DispatchQueue.global(qos: .userInitiated)`. Timing must be captured there, not dispatched back to main.
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- **Infinite cache growth:** Must implement eviction (LRU or size-based) to prevent disk space issues.
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## Don't Hand-Roll
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| Problem | Don't Build | Use Instead | Why |
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|---------|-------------|-------------|-----|
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| SHA256 hashing | Custom hash function | CryptoKit or CommonCrypto | Cryptographic correctness, no collision risk |
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| File system cache directory | Custom path logic | `FileManager.default.urls(for: .cachesDirectory, in: .userDomainMask)` | Standard iOS cache location, auto-managed by OS |
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| Thread-safe cache access | Manual locks | `DispatchQueue` or `NSLock` | Standard concurrency pattern |
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| Orphan/widow detection | Line counting heuristics | CTFrame line origins + paragraph range analysis | CoreText provides exact line positions |
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**Key insight:** The hardest part of this phase is NOT the algorithms -- it's serializing `RDEPUBTextBook` which contains `NSAttributedString` (not Codable) and `NSRange` (not natively Codable in Swift). The serialization strategy is the most consequential design decision.
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## Common Pitfalls
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### Pitfall 1: NSAttributedString Serialization
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**What goes wrong:** Attempting to JSONEncode an `RDEPUBTextBook` fails silently because `NSAttributedString` and `NSRange` are not Codable.
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**Why it happens:** `RDEPUBTextPage.content` is `NSAttributedString`, and `RDEPUBTextPageMetadata` contains `[NSRange]` fields.
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**How to avoid:** Use `NSKeyedArchiver` for the whole object, OR decompose into Codable parts (store HTML + parameters, re-render on load). The second approach is more resilient to code changes but slower on cache load.
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**Warning signs:** `JSONEncoder.encode()` returns nil or throws.
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### Pitfall 2: Cache Invalidation on Code Changes
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**What goes wrong:** After updating the pagination engine code, cached results are stale but the cache key hasn't changed.
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**Why it happens:** Cache key only encodes user-facing parameters (font, size, insets), not code version.
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**How to avoid:** Include a schema version number in the cache key. Bump the version when pagination logic changes.
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**Warning signs:** Pagination quality doesn't improve after code changes until cache is manually cleared.
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### Pitfall 3: NSRange Codable in Metadata
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**What goes wrong:** `RDEPUBTextPageMetadata` conforms to `Codable` but contains `NSRange` fields (`blockRange`, `attachmentRanges`) which don't have native Codable conformance.
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**Why it happens:** `NSRange` is an Objective-C struct, not a Swift Codable type.
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**How to avoid:** Add `Codable` conformance for `NSRange` via an extension that encodes as `{"location": Int, "length": Int}`, or use `NSKeyedArchiver` for the whole metadata.
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**Warning signs:** Compiler error or runtime crash when encoding metadata.
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### Pitfall 4: Image Pages Crossing Boundaries
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**What goes wrong:** A large image that doesn't fit on the current page causes the page to have excessive whitespace or the image gets truncated.
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**Why it happens:** CoreText treats `NSTextAttachment` as inline content and will break the line at the attachment, but doesn't check if the image height exceeds remaining page space.
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**How to avoid:** Before pagination, check attachment heights against remaining page space. If an image won't fit, break the page before the image paragraph.
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**Warning signs:** Pages with only 1-2 lines of text followed by a large gap.
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### Pitfall 5: Cache Thread Safety
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**What goes wrong:** Concurrent reads/writes to the cache directory cause file corruption or crashes.
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**Why it happens:** `builder.build()` runs on a background queue, and multiple `paginate()` calls can overlap (pagination token pattern handles cancellation but not serialization).
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**How to avoid:** Use a serial dispatch queue for all cache operations, or use `NSFileCoordinator` for file-level coordination.
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**Warning signs:** Intermittent crashes on `NSKeyedUnarchiver.unarchiveObject`.
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## Code Examples
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### Cache Key Construction
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```swift
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// Based on WXRead WRChapterPageCount.currentCacheKeyWithBookId:
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// Source: Doc/WXRead/decompiled/WRChapterPageCount.m lines 64-90
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import CryptoKit
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struct RDEPUBTextBookCacheKey: Hashable {
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let bookID: String
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let fontSize: CGFloat
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let lineHeightMultiple: CGFloat
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let contentInsets: UIEdgeInsets
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let pageSize: CGSize
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let schemaVersion: Int // bump when pagination logic changes
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var filename: String {
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let components = [
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bookID,
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String(format: "%.1f", fontSize),
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String(format: "%.2f", lineHeightMultiple),
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String(format: "%.0f", contentInsets.top),
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String(format: "%.0f", contentInsets.left),
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String(format: "%.0f", contentInsets.bottom),
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String(format: "%.0f", contentInsets.right),
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String(format: "%.0f", pageSize.width),
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String(format: "%.0f", pageSize.height),
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"v\(schemaVersion)"
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]
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let raw = components.joined(separator: "_")
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let hash = SHA256.hash(data: Data(raw.utf8))
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return hash.map { String(format: "%02x", $0) }.joined() + ".cache"
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}
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}
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```
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### NSKeyedArchiver Serialization for RDEPUBTextBook
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```swift
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// NSAttributedString supports NSCoding via NSKeyedArchiver
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// RDEPUBTextBook/Chapter/Page need NSCoding conformance or wrapper
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// Option A: Store as NSCoding-compatible wrapper
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final class RDEPUBTextBookArchive: NSObject, NSCoding {
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let chapters: [RDEPUBTextChapterArchive]
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init(chapters: [RDEPUBTextChapterArchive]) { self.chapters = chapters }
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required init?(coder: NSCoder) {
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guard let chapters = coder.decodeObject(forKey: "chapters") as? [RDEPUBTextChapterArchive] else { return nil }
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self.chapters = chapters
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}
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func encode(with coder: NSCoder) {
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coder.encode(chapters, forKey: "chapters")
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}
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}
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// Each RDEPUBTextChapterArchive stores:
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// - attributedContent as NSData (NSKeyedArchiver)
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// - page ranges as [[location, length]]
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// - metadata as JSON Data
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```
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### Performance Sample Collection
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```swift
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// No existing pattern in codebase -- standard iOS approach
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final class RDEPUBTextPerformanceSampler {
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struct Sample {
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let chapterHref: String
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let renderDuration: TimeInterval
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let paginateDuration: TimeInterval
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let pageCount: Int
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let attributedStringLength: Int
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let cacheHit: Bool
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}
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private(set) var samples: [Sample] = []
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func record(_ sample: Sample) {
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samples.append(sample)
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print("[PERF] \(sample.chapterHref): render=\(String(format: "%.1f", sample.renderDuration*1000))ms paginate=\(String(format: "%.1f", sample.paginateDuration*1000))ms pages=\(sample.pageCount) cache=\(sample.cacheHit ? "HIT" : "MISS")")
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}
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func summary() -> String {
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let totalRender = samples.reduce(0) { $0 + $1.renderDuration }
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let totalPaginate = samples.reduce(0) { $0 + $1.paginateDuration }
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let hitRate = samples.filter(\.cacheHit).count
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return "[PERF] chapters=\(samples.count) render=\(String(format: "%.0f", totalRender*1000))ms paginate=\(String(format: "%.0f", totalPaginate*1000))ms cacheHits=\(hitRate)/\(samples.count)"
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}
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}
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```
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## State of the Art
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| Old Approach (assumed) | Current Approach (actual) | When Changed | Impact |
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|------------------------|---------------------------|--------------|--------|
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| `ss_pageRanges` for pagination | `rd_paginatedFrames` via `RDEPUBTextLayouter` | Phase 7 | 4-level semantic break engine already active |
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| No CSS `<link>` handling | `inlineLinkedStyleSheets()` in renderer support | Phase 7 or earlier | EPUB external stylesheets already resolved |
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| Flat CSS injection | 5-layer cascade via `RDEPUBTextStyleSheetPackage` | Phase 7 | default/replace/dark/epub/user layers already built |
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| No page metadata | `RDEPUBTextPageMetadata` on every page | Phase 7 | breakReason, blockKinds, semanticHints already available |
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**Deprecated/outdated in CONTEXT.md:**
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- D-01 (integrate layouter): Already done. `RDEPUBTextBookBuilder` line 196 calls `content.rd_paginatedFrames(size:)`.
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- D-02 (expose metadata): Already done. `RDEPUBTextPage.metadata` is populated from `frame.metadata`.
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- D-04 (CSS `<link>` inline): Already done. `RDEPUBTextRendererSupport.inlineLinkedStyleSheets()` handles this.
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- D-05 (5-layer cascade): Already done. `makeStyleSheetLayers()` produces the 5-layer package.
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## Assumptions Log
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| # | Claim | Section | Risk if Wrong |
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|---|-------|---------|---------------|
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| A1 | `NSKeyedArchiver` can serialize `NSAttributedString` with DTCoreText custom attributes | Cache serialization | Cache would fail silently; fallback to re-render every time |
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| A2 | `CFAbsoluteTimeGetCurrent()` has sufficient precision for millisecond-level timing | Performance sampling | Sub-millisecond operations may show as 0ms |
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| A3 | Cache key schema version bump is sufficient for invalidation on code changes | Cache invalidation | Stale cache could persist if version is forgotten |
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| A4 | CTFrame line origins can detect orphan/widow conditions | Pagination quality | Orphan/widow control would need different approach |
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## Open Questions (RESOLVED)
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|
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1. **Cache storage format: NSKeyedArchiver vs decomposed JSON?** ✅ RESOLVED
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|
- Decision: Use `NSKeyedArchiver` first. Create private `NSCoding` wrapper classes for `RDEPUBTextBook`/`RDEPUBTextChapter`/`RDEPUBTextPage`/`RDEPUBTextPageMetadata`.
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- Rationale: `NSAttributedString` and `NSRange` both support `NSCoding` natively. DTCoreText custom attributes are standard `NSAttributedString` attribute keys (string-typed) and survive archiver round-trip.
|
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- Fallback: If runtime test reveals attribute loss, fall back to decomposed JSON (store HTML + render parameters, re-render on cache load).
|
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|
|
2. **Should cache store full attributed content or just page ranges?** ✅ RESOLVED
|
|
- Decision: Cache full `RDEPUBTextBook` including `NSAttributedString` per page (matches D-01 decision in CONTEXT.md).
|
|
- Rationale: Re-slicing on load would negate the cache performance benefit. Memory pressure is manageable for typical EPUB books (< 500 pages).
|
|
- Mitigation: Cache eviction on memory warning (`didReceiveMemoryWarning` notification).
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|
|
|
3. **Orphan/widow control: how aggressive?** ✅ RESOLVED
|
|
- Decision: Add `RDEPUBTextLayoutConfig` struct with configurable thresholds (`avoidOrphans: Bool = true`, `avoidWidows: Bool = true`), defaulting to enabled.
|
|
- Rationale: Follows the same pattern as `RDEPUBTextRenderStyle` (public struct + Equatable + explicit init). Hard-coding would prevent future tuning.
|
|
- WXRead reference: `WRCoreTextLayoutConfig` uses the same configurable approach.
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|
|
|
## Environment Availability
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|
|
|
| Dependency | Required By | Available | Version | Fallback |
|
|
|------------|------------|-----------|---------|----------|
|
|
| Xcode / iOS SDK | Build & run | ✓ | (system) | -- |
|
|
| DTCoreText | HTML rendering | ✓ | (existing dependency) | -- |
|
|
| CoreText | Pagination | ✓ | (system framework) | -- |
|
|
| CryptoKit | SHA256 for cache key | ✓ | iOS 13+ | CommonCrypto |
|
|
| FileManager | Cache directory | ✓ | (system framework) | -- |
|
|
|
|
**Missing dependencies with no fallback:** None
|
|
|
|
**Missing dependencies with fallback:** None
|
|
|
|
## Validation Architecture
|
|
|
|
### Test Framework
|
|
|
|
| Property | Value |
|
|
|----------|-------|
|
|
| Framework | None detected -- no test target in project |
|
|
| Config file | none |
|
|
| Quick run command | N/A |
|
|
| Full suite command | N/A |
|
|
|
|
### Phase Requirements -> Test Map
|
|
|
|
| Req ID | Behavior | Test Type | Automated Command | File Exists? |
|
|
|--------|----------|-----------|-------------------|-------------|
|
|
| QUAL-01 | Cache hit skips rebuild | manual/runtime | Print cache HIT/MISS in console | N/A |
|
|
| QUAL-02 | avoidPageBreakInside enforced | manual/runtime | Inspect page diagnostics for semanticBoundary breaks | N/A |
|
|
| QUAL-03 | Image sizing rules applied | manual/runtime | Verify image dimensions in diagnostic output | N/A |
|
|
| QUAL-04 | Performance samples output | manual/runtime | Check console for [PERF] lines | N/A |
|
|
|
|
### Sampling Rate
|
|
- **Per task commit:** Build succeeds (`build_sim`)
|
|
- **Per wave merge:** Runtime log includes [PERF] summary and cache HIT/MISS
|
|
- **Phase gate:** Full book builds with cache, second open shows HIT; complex chapter pagination quality visibly improved
|
|
|
|
### Wave 0 Gaps
|
|
- [ ] No test framework exists. All verification is manual/runtime via console output and simulator build.
|
|
- [ ] If automated tests desired, would need to create test target first (out of scope for Phase 8).
|
|
|
|
## Security Domain
|
|
|
|
No new security concerns introduced. Cache files are stored in the app's caches directory (sandboxed). No network requests, no user data exposure.
|
|
|
|
### Applicable ASVS Categories
|
|
|
|
| ASVS Category | Applies | Standard Control |
|
|
|---------------|---------|-----------------|
|
|
| V2 Authentication | no | N/A |
|
|
| V3 Session Management | no | N/A |
|
|
| V4 Access Control | no | N/A |
|
|
| V5 Input Validation | no | N/A |
|
|
| V6 Cryptography | no | SHA256 is one-way hash for cache key, not security-sensitive |
|
|
|
|
## Sources
|
|
|
|
### Primary (HIGH confidence)
|
|
- Project source code: `Sources/RDReaderView/EPUBTextRendering/*.swift` -- direct code inspection
|
|
- `Doc/WXRead/decompiled/WRChapterPageCount.h/.m` -- cache key pattern reference
|
|
- `Doc/WXRead/decompiled/WRCoreTextLayouter.h` -- layout config reference
|
|
- `Doc/WXRead/decompiled/WRCoreTextLayoutFrame.h/.m` -- avoidPageBreakInside reference
|
|
- `Doc/WXRead/resources/css/replace.css` -- CSS rule reference
|
|
|
|
### Secondary (MEDIUM confidence)
|
|
- `Doc/架构对比分析_WXRead_vs_ReadViewSDK.md` -- gap analysis (some gaps already closed)
|
|
|
|
### Tertiary (LOW confidence)
|
|
- A1 (NSKeyedArchiver + DTCoreText attributes): Needs runtime verification
|
|
|
|
## Metadata
|
|
|
|
**Confidence breakdown:**
|
|
- Standard stack: HIGH -- no new dependencies, all system/existing frameworks
|
|
- Architecture: HIGH -- integration points clearly visible in code
|
|
- Pitfalls: HIGH -- serialization issues are well-understood Cocoa patterns
|
|
- Cache design: MEDIUM -- NSKeyedArchiver with DTCoreText custom attributes needs runtime test
|
|
|
|
**Research date:** 2026-05-23
|
|
**Valid until:** 2026-06-23 (30 days -- stable codebase, incremental changes)
|