Autocomplete Feature

Example/CodeEditSourceEditorExample/CodeEditSourceEditorExample.xcodeproj/project.pbxproj

@@ -20,6 +20,7 @@
 		6C1365462B8A7F2D004A1D18 /* LanguagePicker.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6C1365452B8A7F2D004A1D18 /* LanguagePicker.swift */; };
 		6C1365482B8A7FBF004A1D18 /* EditorTheme+Default.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6C1365472B8A7FBF004A1D18 /* EditorTheme+Default.swift */; };
 		6C13654D2B8A821E004A1D18 /* NSColor+Hex.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6C13654C2B8A821E004A1D18 /* NSColor+Hex.swift */; };
+		6C8B564C2E3018CC00DC3F29 /* MockCompletionDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6C8B564B2E3018CC00DC3F29 /* MockCompletionDelegate.swift */; };
 		6CF31D4E2DB6A252006A77FD /* StatusBar.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6CF31D4D2DB6A252006A77FD /* StatusBar.swift */; };
 /* End PBXBuildFile section */
 
@@ -38,6 +39,7 @@
 		6C1365452B8A7F2D004A1D18 /* LanguagePicker.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LanguagePicker.swift; sourceTree = "<group>"; };
 		6C1365472B8A7FBF004A1D18 /* EditorTheme+Default.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "EditorTheme+Default.swift"; sourceTree = "<group>"; };
 		6C13654C2B8A821E004A1D18 /* NSColor+Hex.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "NSColor+Hex.swift"; sourceTree = "<group>"; };
+		6C8B564B2E3018CC00DC3F29 /* MockCompletionDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MockCompletionDelegate.swift; sourceTree = "<group>"; };
 		6CF31D4D2DB6A252006A77FD /* StatusBar.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StatusBar.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
@@ -116,6 +118,7 @@
 		6C13654A2B8A7FD2004A1D18 /* Views */ = {
 			isa = PBXGroup;
 			children = (
+				6C8B564B2E3018CC00DC3F29 /* MockCompletionDelegate.swift */,
 				6C1365312B8A7B94004A1D18 /* ContentView.swift */,
 				6CF31D4D2DB6A252006A77FD /* StatusBar.swift */,
 				6C1365452B8A7F2D004A1D18 /* LanguagePicker.swift */,
@@ -215,6 +218,7 @@
 				6CF31D4E2DB6A252006A77FD /* StatusBar.swift in Sources */,
 				6C13652E2B8A7B94004A1D18 /* CodeEditSourceEditorExampleApp.swift in Sources */,
 				6C1365442B8A7EED004A1D18 /* String+Lines.swift in Sources */,
+				6C8B564C2E3018CC00DC3F29 /* MockCompletionDelegate.swift in Sources */,
 				1CB30C3A2DAA1C28008058A7 /* IndentPicker.swift in Sources */,
 				6C1365322B8A7B94004A1D18 /* ContentView.swift in Sources */,
 				6C1365462B8A7F2D004A1D18 /* LanguagePicker.swift in Sources */,

Example/CodeEditSourceEditorExample/CodeEditSourceEditorExample/Views/ContentView.swift

@@ -22,6 +22,7 @@ struct ContentView: View {
     @State private var editorState = SourceEditorState(
         cursorPositions: [CursorPosition(line: 1, column: 1)]
     )
+    @StateObject private var suggestions: MockCompletionDelegate = MockCompletionDelegate()
 
     @State private var font: NSFont = NSFont.monospacedSystemFont(ofSize: 12, weight: .medium)
     @AppStorage("wrapLines") private var wrapLines: Bool = true
@@ -71,7 +72,8 @@ struct ContentView: View {
                         warningCharacters: warningCharacters
                     )
                 ),
-                state: $editorState
+                state: $editorState,
+                completionDelegate: suggestions
             )
             .overlay(alignment: .bottom) {
                 StatusBar(

Example/CodeEditSourceEditorExample/CodeEditSourceEditorExample/Views/MockCompletionDelegate.swift

@@ -0,0 +1,113 @@
+//
+//  MockCompletionDelegate.swift
+//  CodeEditSourceEditorExample
+//
+//  Created by Khan Winter on 7/22/25.
+//
+
+import SwiftUI
+import CodeEditSourceEditor
+import CodeEditTextView
+
+private let text = [
+    "Lorem",
+    "ipsum",
+    "dolor",
+    "sit",
+    "amet,",
+    "consectetur",
+    "adipiscing",
+    "elit.",
+    "Ut",
+    "condimentum",
+    "dictum",
+    "malesuada.",
+    "Praesent",
+    "ut",
+    "imperdiet",
+    "nulla.",
+    "Vivamus",
+    "feugiat,",
+    "ante",
+    "non",
+    "sagittis",
+    "pellentesque,",
+    "dui",
+    "massa",
+    "consequat",
+    "odio,",
+    "ac",
+    "vestibulum",
+    "augue",
+    "erat",
+    "et",
+    "nunc."
+]
+
+class MockCompletionDelegate: CodeSuggestionDelegate, ObservableObject {
+    class Suggestion: CodeSuggestionEntry {
+        var label: String
+        var detail: String?
+        var pathComponents: [String]? { nil }
+        var targetPosition: CursorPosition? { nil }
+        var sourcePreview: String? { nil }
+        var image: Image = Image(systemName: "dot.square.fill")
+        var imageColor: Color = .gray
+        var deprecated: Bool = false
+
+        init(text: String) {
+            self.label = text
+        }
+    }
+
+    private func randomSuggestions(_ count: Int? = nil) -> [Suggestion] {
+        let count = count ?? Int.random(in: 0..<20)
+        var suggestions: [Suggestion] = []
+        for _ in 0..<count {
+            let randomString = (0..<Int.random(in: 1..<text.count)).map {
+                text[$0]
+            }.shuffled().joined(separator: " ")
+            suggestions.append(Suggestion(text: randomString))
+        }
+        return suggestions
+    }
+
+    var moveCount = 0
+
+    func completionSuggestionsRequested(
+        textView: TextViewController,
+        cursorPosition: CursorPosition
+    ) async -> (windowPosition: CursorPosition, items: [CodeSuggestionEntry])? {
+        try? await Task.sleep(for: .seconds(0.2))
+        return (cursorPosition, randomSuggestions())
+    }
+
+    func completionOnCursorMove(
+        textView: TextViewController,
+        cursorPosition: CursorPosition
+    ) -> [CodeSuggestionEntry]? {
+        moveCount += 1
+        switch moveCount {
+        case 1:
+            return randomSuggestions(2)
+        case 2:
+            return randomSuggestions(20)
+        default:
+            moveCount = 0
+            return nil
+        }
+    }
+
+    func completionWindowApplyCompletion(
+        item: CodeSuggestionEntry,
+        textView: TextViewController,
+        cursorPosition: CursorPosition?
+    ) {
+        guard let suggestion = item as? Suggestion else {
+            return
+        }
+        textView.textView.undoManager?.beginUndoGrouping()
+        textView.textView.insertText(suggestion.label)
+        textView.textView.undoManager?.endUndoGrouping()
+    }
+}

Example/CodeEditSourceEditorExample/CodeEditSourceEditorExample/Views/StatusBar.swift

@@ -104,7 +104,7 @@ struct StatusBar: View {
                     }
                 }
                 scrollPosition
-                Text(getLabel(state.cursorPositions))
+                Text(getLabel(state.cursorPositions ?? []))
             }
             .foregroundStyle(.secondary)
 

Sources/CodeEditSourceEditor/CodeSuggestion/Model/CodeSuggestionDelegate.swift

@@ -0,0 +1,38 @@
+//
+//  CodeSuggestionDelegate.swift
+//  CodeEditSourceEditor
+//
+//  Created by Abe Malla on 12/26/24.
+//
+
+public protocol CodeSuggestionDelegate: AnyObject {
+    func completionTriggerCharacters() -> Set<String>
+
+    func completionSuggestionsRequested(
+        textView: TextViewController,
+        cursorPosition: CursorPosition
+    ) async -> (windowPosition: CursorPosition, items: [CodeSuggestionEntry])?
+
+    // This can't be async, we need it to be snappy. At most, it should just be filtering completion items
+    func completionOnCursorMove(
+        textView: TextViewController,
+        cursorPosition: CursorPosition
+    ) -> [CodeSuggestionEntry]?
+
+    // Optional
+    func completionWindowDidClose()
+
+    func completionWindowApplyCompletion(
+        item: CodeSuggestionEntry,
+        textView: TextViewController,
+        cursorPosition: CursorPosition?
+    )
+    // Optional
+    func completionWindowDidSelect(item: CodeSuggestionEntry)
+}
+
+public extension CodeSuggestionDelegate {
+    func completionTriggerCharacters() -> Set<String> { [] }
+    func completionWindowDidClose() { }
+    func completionWindowDidSelect(item: CodeSuggestionEntry) { }
+}

Sources/CodeEditSourceEditor/CodeSuggestion/Model/CodeSuggestionEntry.swift

@@ -0,0 +1,25 @@
+//
+//  CodeSuggestionEntry.swift
+//  CodeEditSourceEditor
+//
+//  Created by Khan Winter on 7/22/25.
+//
+
+import AppKit
+import SwiftUI
+
+/// Represents an item that can be displayed in the code suggestion view
+public protocol CodeSuggestionEntry {
+    var label: String { get }
+    var detail: String? { get }
+
+    /// Leave as `nil` if the link is in the same document.
+    var pathComponents: [String]? { get }
+    var targetPosition: CursorPosition? { get }
+    var sourcePreview: String? { get }
+
+    var image: Image { get }
+    var imageColor: Color { get }
+
+    var deprecated: Bool { get }
+}

Sources/CodeEditSourceEditor/CodeSuggestion/Model/SuggestionViewModel.swift

@@ -0,0 +1,112 @@
+//
+//  SuggestionViewModel.swift
+//  CodeEditSourceEditor
+//
+//  Created by Khan Winter on 7/22/25.
+//
+
+import AppKit
+
+final class SuggestionViewModel: ObservableObject {
+    /// The items to be displayed in the window
+    @Published var items: [CodeSuggestionEntry] = []
+    var itemsRequestTask: Task<Void, Never>?
+    weak var activeTextView: TextViewController?
+
+    var delegate: CodeSuggestionDelegate? {
+        activeTextView?.completionDelegate
+    }
+
+    func showCompletions(
+        textView: TextViewController,
+        delegate: CodeSuggestionDelegate,
+        cursorPosition: CursorPosition,
+        showWindowOnParent: @escaping @MainActor (NSWindow, NSRect) -> Void
+    ) {
+        self.activeTextView = nil
+        itemsRequestTask?.cancel()
+
+        guard let targetParentWindow = textView.view.window else { return }
+
+        self.activeTextView = textView
+        itemsRequestTask = Task {
+            defer { itemsRequestTask = nil }
+
+            do {
+                guard let completionItems = await delegate.completionSuggestionsRequested(
+                    textView: textView,
+                    cursorPosition: cursorPosition
+                ) else {
+                    return
+                }
+
+                try Task.checkCancellation()
+                try await MainActor.run {
+                    try Task.checkCancellation()
+
+                    guard let cursorPosition = textView.resolveCursorPosition(completionItems.windowPosition),
+                          let cursorRect = textView.textView.layoutManager.rectForOffset(
+                            cursorPosition.range.location
+                          ),
+                          let cursorRect = textView.view.window?.convertToScreen(
+                            textView.textView.convert(cursorRect, to: nil)
+                          ) else {
+                        return
+                    }
+
+                    self.items = completionItems.items
+                    showWindowOnParent(targetParentWindow, cursorRect)
+                }
+            } catch {
+                return
+            }
+        }
+    }
+
+    func cursorsUpdated(
+        textView: TextViewController,
+        delegate: CodeSuggestionDelegate,
+        position: CursorPosition,
+        close: () -> Void
+    ) {
+        guard itemsRequestTask == nil else { return }
+
+        if activeTextView !== textView {
+            close()
+            return
+        }
+
+        guard let newItems = delegate.completionOnCursorMove(
+            textView: textView,
+            cursorPosition: position
+        ),
+              !newItems.isEmpty else {
+            close()
+            return
+        }
+
+        items = newItems
+    }
+
+    func didSelect(item: CodeSuggestionEntry) {
+        delegate?.completionWindowDidSelect(item: item)
+    }
+
+    func applySelectedItem(item: CodeSuggestionEntry, window: NSWindow?) {
+        guard let activeTextView,
+              let cursorPosition = activeTextView.cursorPositions.first else {
+            return
+        }
+        self.delegate?.completionWindowApplyCompletion(
+            item: item,
+            textView: activeTextView,
+            cursorPosition: cursorPosition
+        )
+        window?.close()
+    }
+
+    func willClose() {
+        items.removeAll()
+        activeTextView = nil
+    }
+}