feat: Add support for text snippets

Sources/VocaMac/Models/AppState.swift

@@ -198,6 +198,9 @@ final class AppState: ObservableObject {
         selectedAudioDeviceName = device?.name ?? ""
     }
 
+    /// Custom text snippets for expansion
+    @Published var snippets: [Snippet] = []
+
     // MARK: - Services
 
     let audioEngine: AudioRecording
@@ -208,6 +211,7 @@ final class AppState: ObservableObject {
     let soundManager: SoundPlaying
     let cursorOverlay: CursorOverlayManaging
     let statsManager: StatsManaging
+    let snippetExpander: SnippetExpanding
     let updateChecker = UpdateChecker()
     let permissionManager: any PermissionManaging
 
@@ -288,6 +292,7 @@ final class AppState: ObservableObject {
         soundManager: SoundPlaying = SoundManager(),
         cursorOverlay: CursorOverlayManaging,
         statsManager: StatsManaging,
+        snippetExpander: SnippetExpanding = SnippetExpander(),
         permissionManager: (any PermissionManaging)? = nil,
         skipSystemIntegration: Bool = false
     ) {
@@ -299,10 +304,12 @@ final class AppState: ObservableObject {
         self.soundManager = soundManager
         self.cursorOverlay = cursorOverlay
         self.statsManager = statsManager
+        self.snippetExpander = snippetExpander
         self.permissionManager = permissionManager ?? PermissionManager(audioEngine: audioEngine, hotKeyManager: hotKeyManager)
         self.skipSystemIntegration = skipSystemIntegration
 
         VocaLogger.info(.appState, "Initializing... id=\(ObjectIdentifier(self))")
+        loadSnippets()
         if !skipSystemIntegration {
             syncLaunchAtLogin()
         }
@@ -529,6 +536,16 @@ final class AppState: ObservableObject {
             .sink { [weak self] _ in self?.objectWillChange.send() }
             .store(in: &cancellables)
 
+        // Auto-save snippets when changed. @Published emits on willSet, so
+        // persist the emitted array — reading self.snippets here would save
+        // the previous state and leave the latest change unsaved.
+        $snippets
+            .dropFirst()  // skip the subscription replay of the just-loaded value
+            .sink { [weak self] snippets in
+                self?.saveSnippets(snippets)
+            }
+            .store(in: &cancellables)
+
         // Check permissions
         checkPermissions()
 
@@ -1023,11 +1040,17 @@ final class AppState: ObservableObject {
 
             let trimmedText = result.text.trimmingCharacters(in: .whitespacesAndNewlines)
             if !trimmedText.isEmpty {
-                let polished = DictationOutputFormatter.apply(
+                // Polish first, expand second. Snippet expansions are literal
+                // text the user authored, so auto-capitalization must not
+                // rewrite them (an email snippet would become Me@example.com).
+                // Trigger matching is case-insensitive, so capitalizing the
+                // trigger beforehand still matches.
+                let polishedSource = DictationOutputFormatter.apply(
                     trimmedText,
                     autoCapitalize: autoCapitalize,
                     appendTrailingSpace: appendTrailingSpace
                 )
+                let polished = expandSnippets(in: polishedSource)
                 if injectResult {
                     textInjector.inject(
                         text: polished,
@@ -1576,4 +1599,33 @@ final class AppState: ObservableObject {
         hasCompletedOnboarding = true
         VocaLogger.info(.appState, "Onboarding completed")
     }
+
+    // MARK: - Snippets Management
+
+    private func loadSnippets() {
+        if let data = UserDefaults.standard.data(forKey: "vocamac.snippets") {
+            do {
+                snippets = try JSONDecoder().decode([Snippet].self, from: data)
+            } catch {
+                VocaLogger.error(.appState, "Failed to decode snippets: \(error)")
+            }
+        }
+    }
+
+    func saveSnippets() {
+        saveSnippets(snippets)
+    }
+
+    private func saveSnippets(_ snippets: [Snippet]) {
+        do {
+            let encoded = try JSONEncoder().encode(snippets)
+            UserDefaults.standard.set(encoded, forKey: "vocamac.snippets")
+        } catch {
+            VocaLogger.error(.appState, "Failed to encode snippets: \(error)")
+        }
+    }
+
+    func expandSnippets(in text: String) -> String {
+        return snippetExpander.expand(in: text, using: snippets)
+    }
 }

Sources/VocaMac/Models/SettingsPage.swift

@@ -9,6 +9,7 @@ import SwiftUI
 /// Top-level settings topics shown in the left sidebar.
 enum SettingsPage: String, CaseIterable, Identifiable, Hashable {
     case dictation
+    case snippets
     case speechModel
     case audio
     case performance
@@ -22,6 +23,7 @@ enum SettingsPage: String, CaseIterable, Identifiable, Hashable {
     var title: String {
         switch self {
         case .dictation: return "Dictation"
+        case .snippets: return "Snippets"
         case .speechModel: return "Speech Model"
         case .audio: return "Audio"
         case .performance: return "Performance"
@@ -35,6 +37,7 @@ enum SettingsPage: String, CaseIterable, Identifiable, Hashable {
     var systemImage: String {
         switch self {
         case .dictation: return "mic"
+        case .snippets: return "text.quote"
         case .speechModel: return "brain"
         case .audio: return "waveform"
         case .performance: return "bolt.circle"

Sources/VocaMac/Models/SettingsSearchIndex.swift

@@ -63,6 +63,15 @@ enum SettingsSearchIndex {
             keywords: ["capitalize", "output", "sentence", "punctuation"]
         ),
 
+        // Snippets
+        SettingsSearchEntry(
+            id: "snippets",
+            page: .snippets,
+            title: "Custom Snippets",
+            subtitle: "Replace spoken triggers with saved text",
+            keywords: ["snippet", "shortcut", "expansion", "trigger", "replace", "macro", "abbreviation"]
+        ),
+
         // Speech Model
         SettingsSearchEntry(
             id: "models",

Sources/VocaMac/Models/Snippet.swift

@@ -0,0 +1,18 @@
+// Snippet.swift
+// VocaMac
+//
+// Model representing a custom text snippet with a trigger phrase and expansion text.
+
+import Foundation
+
+struct Snippet: Identifiable, Codable, Equatable {
+    var id: UUID
+    var trigger: String
+    var expansion: String
+
+    init(id: UUID = UUID(), trigger: String = "", expansion: String = "") {
+        self.id = id
+        self.trigger = trigger
+        self.expansion = expansion
+    }
+}

Sources/VocaMac/Services/ServiceProtocols.swift

@@ -170,3 +170,9 @@ protocol StatsManaging: AnyObject {
     func recordTranscription(_ transcription: VocaTranscription)
     func resetStats()
 }
+
+// MARK: - SnippetExpanding
+
+protocol SnippetExpanding: AnyObject {
+    func expand(in text: String, using snippets: [Snippet]) -> String
+}

Sources/VocaMac/Services/SnippetExpander.swift

@@ -0,0 +1,79 @@
+// SnippetExpander.swift
+// VocaMac
+//
+// Pure logic for expanding text snippets with regex support.
+
+import Foundation
+
+final class SnippetExpander: SnippetExpanding {
+    func expand(in text: String, using snippets: [Snippet]) -> String {
+        guard !snippets.isEmpty else { return text }
+
+        // Sort snippets by trigger length descending to prioritize longer triggers
+        let sortedSnippets = snippets
+            .filter { !$0.trigger.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty }
+            .sorted { $0.trigger.count > $1.trigger.count }
+
+        guard !sortedSnippets.isEmpty else { return text }
+
+        // Build a single combined regex to avoid cascading expansions
+        // and handle different boundary requirements for word/non-word triggers.
+        var patterns: [String] = []
+        for snippet in sortedSnippets {
+            let trigger = snippet.trigger.trimmingCharacters(in: .whitespacesAndNewlines)
+            let escapedTrigger = NSRegularExpression.escapedPattern(for: trigger)
+
+            let prefix: String
+            if let first = trigger.first, first.isWordCharacter {
+                prefix = "\\b"
+            } else {
+                prefix = "(?<!\\S)"
+            }
+
+            let suffix: String
+            if let last = trigger.last, last.isWordCharacter {
+                suffix = "\\b"
+            } else {
+                suffix = "(?!\\S)"
+            }
+
+            // Capture each trigger in its own group to identify which one matched
+            patterns.append("(\(prefix)\(escapedTrigger)\(suffix))")
+        }
+
+        let combinedPattern = patterns.joined(separator: "|")
+
+        guard let regex = try? NSRegularExpression(pattern: combinedPattern, options: [.caseInsensitive]) else {
+            return text
+        }
+
+        let nsString = text as NSString
+        let matches = regex.matches(in: text, options: [], range: NSRange(location: 0, length: nsString.length))
+
+        // Replace matches in reverse order to keep ranges valid
+        var result = text
+        for match in matches.reversed() {
+            // Find which group matched (group 0 is the whole match, groups 1..N are our snippets)
+            for i in 1...match.numberOfRanges - 1 {
+                let range = match.range(at: i)
+                if range.location != NSNotFound {
+                    let snippet = sortedSnippets[i - 1]
+
+                    // Since we are going in reverse, we can just use string replacement on the range.
+                    if let resultRange = Range(match.range, in: result) {
+                        result.replaceSubrange(resultRange, with: snippet.expansion)
+                    }
+                    break
+                }
+            }
+        }
+
+        return result
+    }
+}
+
+private extension Character {
+    var isWordCharacter: Bool {
+        return self.isLetter || self.isNumber || self == "_"
+    }
+}