Epub阅读器0.0.1

2026-05-21 19:40:51 +08:00
commit daa36d8fe7
559 changed files with 106266 additions and 0 deletions
@@ -0,0 +1,68 @@
+import Foundation
+
+final class RDEPUBTextSearchEngine: RDEPUBSearchEngine {
+    private let textBook: RDEPUBTextBook
+    private let publication: RDEPUBPublication
+
+    init(textBook: RDEPUBTextBook, publication: RDEPUBPublication) {
+        self.textBook = textBook
+        self.publication = publication
+    }
+
+    func search(keyword: String) -> [RDEPUBSearchMatch] {
+        let normalizedKeyword = keyword.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !normalizedKeyword.isEmpty else {
+            return []
+        }
+
+        var matches: [RDEPUBSearchMatch] = []
+        for chapter in textBook.chapters {
+            let source = chapter.attributedContent.string as NSString
+            let fullLength = source.length
+            guard fullLength > 0 else {
+                continue
+            }
+
+            let normalizedHref = publication.resourceResolver.normalizedHref(chapter.href) ?? chapter.href
+            var localMatchIndex = 0
+            var searchRange = NSRange(location: 0, length: fullLength)
+
+            while searchRange.length > 0 {
+                let foundRange = source.range(of: normalizedKeyword, options: [.caseInsensitive], range: searchRange)
+                guard foundRange.location != NSNotFound else {
+                    break
+                }
+
+                let progressionDenominator = max(fullLength - 1, 1)
+                let progression = Double(foundRange.location) / Double(progressionDenominator)
+                matches.append(
+                    RDEPUBSearchMatch(
+                        href: normalizedHref,
+                        progression: progression,
+                        previewText: previewText(in: source, matchRange: foundRange),
+                        localMatchIndex: localMatchIndex,
+                        rangeLocation: foundRange.location,
+                        rangeLength: foundRange.length
+                    )
+                )
+
+                localMatchIndex += 1
+                let nextLocation = foundRange.location + max(foundRange.length, 1)
+                if nextLocation >= fullLength {
+                    break
+                }
+                searchRange = NSRange(location: nextLocation, length: fullLength - nextLocation)
+            }
+        }
+
+        return matches
+    }
+
+    private func previewText(in text: NSString, matchRange: NSRange) -> String {
+        let previewRadius = 12
+        let start = max(matchRange.location - previewRadius, 0)
+        let end = min(matchRange.location + matchRange.length + previewRadius, text.length)
+        let range = NSRange(location: start, length: max(end - start, 0))
+        return text.substring(with: range).trimmingCharacters(in: .whitespacesAndNewlines)
+    }
+}