| 1 | import Ed |
| 2 | import Foundation |
| 3 | import UIKit |
| 4 | |
| 5 | @MainActor |
| 6 | final class ChatViewModel: ObservableObject { |
| 7 | @Published var input = "What is my battery level?" |
| 8 | @Published var transcript = "" |
| 9 | @Published var status = "Not loaded" |
| 10 | @Published var isLoaded = false |
| 11 | @Published var isBusy = false |
| 12 | @Published var showApproval = false |
| 13 | @Published var approvalSummary = "" |
| 14 | |
| 15 | private let notes = NotesStore() |
| 16 | private lazy var agent = EdAgent { [weak self] call in |
| 17 | guard let self else { return .deny } |
| 18 | return await self.requestApproval(for: call) |
| 19 | } |
| 20 | private var approvalContinuation: CheckedContinuation<EdApprovalDecision, Never>? |
| 21 | |
| 22 | func load() async { |
| 23 | isBusy = true |
| 24 | defer { isBusy = false } |
| 25 | do { |
| 26 | try await agent.register(BatteryTool()) |
| 27 | try await agent.register(SaveNoteTool(notes: notes)) |
| 28 | _ = try await agent.loadDefaultAgentModel( |
| 29 | systemPrompt: "You are a concise assistant inside an iOS app. Use tools when useful." |
| 30 | ) |
| 31 | isLoaded = true |
| 32 | status = "Ready" |
| 33 | } catch { |
| 34 | status = "Load failed: \(error.localizedDescription)" |
| 35 | } |
| 36 | } |
| 37 | |
| 38 | func send() async { |
| 39 | let message = input |
| 40 | input = "" |
| 41 | isBusy = true |
| 42 | defer { isBusy = false } |
| 43 | do { |
| 44 | let reply = try await agent.run(message) |
| 45 | transcript += "You: \(message)\n\nEd: \(reply.text)\n\n" |
| 46 | status = "Finished in \(reply.duration) with \(reply.toolRounds) tool round(s)" |
| 47 | } catch { |
| 48 | status = "Turn failed: \(error.localizedDescription)" |
| 49 | } |
| 50 | } |
| 51 | |
| 52 | func resolveApproval(_ decision: EdApprovalDecision) { |
| 53 | showApproval = false |
| 54 | approvalContinuation?.resume(returning: decision) |
| 55 | approvalContinuation = nil |
| 56 | } |
| 57 | |
| 58 | private func requestApproval(for call: EdToolCall) async -> EdApprovalDecision { |
| 59 | approvalSummary = "\(call.name) wants to run with: \(call.arguments)" |
| 60 | showApproval = true |
| 61 | return await withCheckedContinuation { continuation in |
| 62 | approvalContinuation = continuation |
| 63 | } |
| 64 | } |
| 65 | } |
| 66 | |
| 67 | private struct BatteryTool: EdTool { |
| 68 | let definition = EdToolDefinition.readOnly( |
| 69 | name: "battery_level", |
| 70 | description: "Read the device battery percentage", |
| 71 | parametersSchema: #"{"type":"object","properties":{},"additionalProperties":false}"# |
| 72 | ) |
| 73 | |
| 74 | func execute(arguments: String) async throws -> String { |
| 75 | await MainActor.run { |
| 76 | UIDevice.current.isBatteryMonitoringEnabled = true |
| 77 | let level = UIDevice.current.batteryLevel |
| 78 | return level < 0 ? "Battery level is unavailable." : "Battery is at \(Int(level * 100)) percent." |
| 79 | } |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | private actor NotesStore { |
| 84 | private var notes: [String] = [] |
| 85 | |
| 86 | func save(_ note: String) -> Int { |
| 87 | notes.append(note) |
| 88 | return notes.count |
| 89 | } |
| 90 | } |
| 91 | |
| 92 | private struct SaveNoteTool: EdTool { |
| 93 | struct Arguments: Decodable { let text: String } |
| 94 | |
| 95 | let notes: NotesStore |
| 96 | let definition = EdToolDefinition.mutating( |
| 97 | name: "save_note", |
| 98 | description: "Save a note in the app", |
| 99 | parametersSchema: #"{"type":"object","properties":{"text":{"type":"string"}},"required":["text"],"additionalProperties":false}"# |
| 100 | ) |
| 101 | |
| 102 | func execute(arguments: String) async throws -> String { |
| 103 | let decoded = try JSONDecoder().decode(Arguments.self, from: Data(arguments.utf8)) |
| 104 | let count = await notes.save(decoded.text) |
| 105 | return "Saved note number \(count)." |
| 106 | } |
| 107 | } |