feat(mac): add agent-controlled Canvas panel

apps/macos/Sources/Clawdis/CanvasManager.swift

@@ -0,0 +1,77 @@
+import AppKit
+import Foundation
+
+@MainActor
+final class CanvasManager {
+    static let shared = CanvasManager()
+
+    private var panelController: CanvasWindowController?
+    private var panelSessionKey: String?
+
+    /// Optional anchor provider (e.g. menu bar status item). If nil, Canvas anchors to the mouse cursor.
+    var defaultAnchorProvider: (() -> NSRect?)?
+
+    private nonisolated static let canvasRoot: URL = {
+        let base = FileManager.default.urls(for: .applicationSupportDirectory, in: .userDomainMask).first!
+        return base.appendingPathComponent("Clawdis/canvas", isDirectory: true)
+    }()
+
+    func show(sessionKey: String, path: String? = nil) throws -> String {
+        let anchorProvider = self.defaultAnchorProvider ?? Self.mouseAnchorProvider
+        let session = sessionKey.trimmingCharacters(in: .whitespacesAndNewlines)
+        if let controller = self.panelController, self.panelSessionKey == session {
+            controller.presentAnchoredPanel(anchorProvider: anchorProvider)
+            controller.goto(path: path ?? "/")
+            return controller.directoryPath
+        }
+
+        self.panelController?.close()
+        self.panelController = nil
+        self.panelSessionKey = nil
+
+        try FileManager.default.createDirectory(at: Self.canvasRoot, withIntermediateDirectories: true)
+        let controller = try CanvasWindowController(
+            sessionKey: session,
+            root: Self.canvasRoot,
+            presentation: .panel(anchorProvider: anchorProvider))
+        self.panelController = controller
+        self.panelSessionKey = session
+        controller.showCanvas(path: path ?? "/")
+        return controller.directoryPath
+    }
+
+    func hide(sessionKey: String) {
+        let session = sessionKey.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard self.panelSessionKey == session else { return }
+        self.panelController?.hideCanvas()
+    }
+
+    func hideAll() {
+        self.panelController?.hideCanvas()
+    }
+
+    func goto(sessionKey: String, path: String) throws {
+        _ = try self.show(sessionKey: sessionKey, path: path)
+    }
+
+    func eval(sessionKey: String, javaScript: String) async throws -> String {
+        _ = try self.show(sessionKey: sessionKey, path: nil)
+        guard let controller = self.panelController else { return "" }
+        return await controller.eval(javaScript: javaScript)
+    }
+
+    func snapshot(sessionKey: String, outPath: String?) async throws -> String {
+        _ = try self.show(sessionKey: sessionKey, path: nil)
+        guard let controller = self.panelController else {
+            throw NSError(domain: "Canvas", code: 21, userInfo: [NSLocalizedDescriptionKey: "canvas not available"])
+        }
+        return try await controller.snapshot(to: outPath)
+    }
+
+    // MARK: - Anchoring
+
+    private static func mouseAnchorProvider() -> NSRect? {
+        let pt = NSEvent.mouseLocation
+        return NSRect(x: pt.x, y: pt.y, width: 1, height: 1)
+    }
+}