Improve search functionality (#578)

- Resolved issues with the search feature.
- Implemented diacritic-insensitive searching.
- Enhanced search to be insensitive to Unicode categories: Mark (M), Punctuation (P), Symbol (S), and Control (C), as well as the Arabic Tatweel character (U+0640).
- Normalized search strings using Unicode Normalization Form KD.
- Unified search and autocomplete behavior by adopting a consistent matching algorithm.

TODO:
- Integrate Full-Text Search (FTS) for enhanced searching capabilities.
- Extend search functionality to include all downloaded translations and tafseers.
- Implement collapsible search results, allowing users to collapse specific results for easier navigation to subsequent entries.

Data/VerseTextPersistence/GRDBVerseTextPersistence.swift

@@ -11,18 +11,6 @@ import QuranKit
 import SQLitePersistence
 
 public struct GRDBQuranVerseTextPersistence: VerseTextPersistence {
-    // MARK: Lifecycle
-
-    public init(fileURL: URL) {
-        self.init(mode: .arabic, fileURL: fileURL)
-    }
-
-    public init(mode: Mode, fileURL: URL) {
-        persistence = GRDBVerseTextPersistence(fileURL: fileURL, textTable: mode.tabelName)
-    }
-
-    // MARK: Public
-
     public enum Mode {
         case arabic
         case share
@@ -39,6 +27,18 @@ public struct GRDBQuranVerseTextPersistence: VerseTextPersistence {
         }
     }
 
+    // MARK: Lifecycle
+
+    public init(fileURL: URL) {
+        self.init(mode: .arabic, fileURL: fileURL)
+    }
+
+    public init(mode: Mode, fileURL: URL) {
+        persistence = GRDBVerseTextPersistence(fileURL: fileURL, textTable: mode.tabelName)
+    }
+
+    // MARK: Public
+
     public func textForVerses(_ verses: [AyahNumber]) async throws -> [AyahNumber: String] {
         try await persistence.textForVerses(verses, transform: textFromRow)
     }
@@ -175,6 +175,7 @@ private struct GRDBVerseTextPersistence {
     func search(for term: String, quran: Quran) async throws -> [(verse: AyahNumber, text: String)] {
         try await db.read { db in
             // TODO: Use match for FTS.
+            // Use like to match "_" in the Arabic regex as `match` treats "_" as a regular character.
             let request = SQLRequest<Row>("""
             SELECT text, sura, ayah
             FROM \(sql: searchTable)

Domain/QuranTextKit/Sources/Search/Searchers/CompositeSearcher.swift

@@ -12,7 +12,7 @@ import TranslationService
 import VerseTextPersistence
 import VLogging
 
-public struct CompositeSearcher: Searcher {
+public struct CompositeSearcher {
     // MARK: Lifecycle
 
     init(
@@ -48,32 +48,39 @@ public struct CompositeSearcher: Searcher {
     // MARK: Public
 
     public func autocomplete(term: String, quran: Quran) async throws -> [String] {
-        logger.info("Autocompleting term: \(term)")
+        guard let term = SearchTerm(term) else {
+            return []
+        }
+        logger.info("Autocompleting term: \(term.compactQuery)")
 
         let autocompletions = try await simpleSearchers.asyncMap { searcher in
             try await searcher.autocomplete(term: term, quran: quran)
         }
         var results = autocompletions.flatMap { $0 }
 
-        if results.isEmpty {
-            results = try await translationsSearcher.autocomplete(term: term, quran: quran)
+        if shouldPerformTranslationSearch(simpleSearchResults: results, term: term.compactQuery) {
+            results += try await translationsSearcher.autocomplete(term: term, quran: quran)
         }
-        if !results.contains(term) {
-            results.insert(term, at: 0)
+        if !results.contains(term.compactQuery) {
+            results.insert(term.compactQuery, at: 0)
         }
         return results.orderedUnique()
     }
 
     public func search(for term: String, quran: Quran) async throws -> [SearchResults] {
-        logger.info("Search for: \(term)")
+        guard let term = SearchTerm(term) else {
+            return []
+        }
+        logger.info("Search for: \(term.compactQuery)")
+
         let searchResults = try await simpleSearchers.asyncMap { searcher in
             try await searcher.search(for: term, quran: quran)
         }
         var results = searchResults
             .flatMap { $0 }
             .filter { !$0.items.isEmpty } // Remove empty search results
-        if results.isEmpty {
-            results = try await translationsSearcher.search(for: term, quran: quran)
+        if shouldPerformTranslationSearch(simpleSearchResults: results, term: term.compactQuery) {
+            results += try await translationsSearcher.search(for: term, quran: quran)
                 .filter { !$0.items.isEmpty } // Remove empty search results
         }
 
@@ -96,4 +103,8 @@ public struct CompositeSearcher: Searcher {
             .map { source, items in SearchResults(source: source, items: items) }
             .sorted { $0.source < $1.source }
     }
+
+    private func shouldPerformTranslationSearch(simpleSearchResults: [some Any], term: String) -> Bool {
+        simpleSearchResults.isEmpty || (!term.containsArabic() && !term.containsOnlyNumbers())
+    }
 }

Domain/QuranTextKit/Sources/Search/Searchers/NumberSearcher.swift

@@ -15,14 +15,14 @@ struct NumberSearcher: Searcher {
 
     let quranVerseTextPersistence: VerseTextPersistence
 
-    func autocomplete(term: String, quran: Quran) throws -> [String] {
-        if Int(term) != nil {
-            return resultsProcessor.buildAutocompletions(searchResults: [term], term: term)
+    func autocomplete(term: SearchTerm, quran: Quran) throws -> [String] {
+        if Int(term.compactQuery) != nil {
+            return term.buildAutocompletions(searchResults: [term.compactQuery])
         }
         return []
     }
 
-    func search(for term: String, quran: Quran) async throws -> [SearchResults] {
+    func search(for term: SearchTerm, quran: Quran) async throws -> [SearchResults] {
         let items: [SearchResult] = try await search(for: term, quran: quran)
         return [SearchResults(source: .quran, items: items)]
     }
@@ -35,10 +35,8 @@ struct NumberSearcher: Searcher {
         return formatter
     }()
 
-    private let resultsProcessor = SearchResultsProcessor()
-
-    private func search(for term: String, quran: Quran) async throws -> [SearchResult] {
-        let components = parseIntArray(term)
+    private func search(for term: SearchTerm, quran: Quran) async throws -> [SearchResult] {
+        let components = parseIntArray(term.compactQuery)
         guard !components.isEmpty else {
             return []
         }
@@ -99,17 +97,11 @@ struct NumberSearcher: Searcher {
         guard !components.isEmpty, components.count <= 2 else {
             return []
         }
-        guard let first = parseInt(components[0]) else {
+        let result = components.compactMap { parseInt($0) }
+        if result.count != components.count {
             return []
         }
-        if components.count == 1 {
-            return [first]
-        } else {
-            guard let second = parseInt(components[1]) else {
-                return []
-            }
-            return [first, second]
-        }
+        return result
     }
 
     private func parseInt(_ value: String) -> Int? {