Add VertexAI Sample to repo (#1675)

Author: paulb777

Diff for: .github/workflows/vertexai.yml

@@ -0,0 +1,48 @@
+name: vertexai
+
+on:
+  pull_request:
+    paths:
+    - 'vertexai/**'
+  schedule:
+    # Run every day at 11pm (PST) - cron uses UTC times
+    - cron:  '0 7 * * *'
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.head_ref || github.ref }}
+  cancel-in-progress: true
+
+env:
+  SAMPLE: vertexai
+
+jobs:
+  spm:
+    name: spm (Xcode ${{ matrix.xcode }} - ${{ matrix.os }})
+    runs-on: macOS-15
+    strategy:
+      matrix:
+        xcode: ["16.1"]
+        os: [iOS]
+        include:
+          - os: iOS
+            device: iPhone 16
+    env:
+      SETUP: vertexai
+      SPM: true
+      DIR: vertexai
+      OS: ${{ matrix.os }}
+      DEVICE: ${{ matrix.device }}
+      TEST: false
+      XCODE_VERSION: ${{ matrix.xcode }}
+      DEVELOPER_DIR: /Applications/Xcode_${{ matrix.xcode }}.app/Contents/Developer
+    steps:
+      - name: Checkout
+        uses: actions/checkout@master
+      - name: Setup
+        run: |
+          gem install xcpretty
+      - name: Placeholder GoogleService-Info.plist good enough for build only testing.
+        run: cp ./mock-GoogleService-Info.plist ./vertexai/GoogleService-Info.plist
+      - name: Build and Test SwiftUI (${{ matrix.os }})
+        run: ./scripts/test.sh

Diff for: vertexai/ChatSample/Assets.xcassets/AccentColor.colorset/Contents.json

@@ -0,0 +1,11 @@
+{
+  "colors" : [
+    {
+      "idiom" : "universal"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

Diff for: vertexai/ChatSample/Assets.xcassets/AppIcon.appiconset/Contents.json

@@ -0,0 +1,13 @@
+{
+  "images" : [
+    {
+      "idiom" : "universal",
+      "platform" : "ios",
+      "size" : "1024x1024"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

Diff for: vertexai/ChatSample/Assets.xcassets/Contents.json

@@ -0,0 +1,6 @@
+{
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

Diff for: vertexai/ChatSample/Models/ChatMessage.swift

@@ -0,0 +1,64 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import Foundation
+
+enum Participant {
+  case system
+  case user
+}
+
+struct ChatMessage: Identifiable, Equatable {
+  let id = UUID().uuidString
+  var message: String
+  let participant: Participant
+  var pending = false
+
+  static func pending(participant: Participant) -> ChatMessage {
+    Self(message: "", participant: participant, pending: true)
+  }
+}
+
+extension ChatMessage {
+  static var samples: [ChatMessage] = [
+    .init(message: "Hello. What can I do for you today?", participant: .system),
+    .init(message: "Show me a simple loop in Swift.", participant: .user),
+    .init(message: """
+    Sure, here is a simple loop in Swift:
+
+    # Example 1
+    ```
+    for i in 1...5 {
+      print("Hello, world!")
+    }
+    ```
+
+    This loop will print the string "Hello, world!" five times. The for loop iterates over a range of numbers,
+    in this case the numbers from 1 to 5. The variable i is assigned each number in the range, and the code inside the loop is executed.
+
+    **Here is another example of a simple loop in Swift:**
+    ```swift
+    var sum = 0
+    for i in 1...100 {
+      sum += i
+    }
+    print("The sum of the numbers from 1 to 100 is \\(sum).")
+    ```
+
+    This loop calculates the sum of the numbers from 1 to 100. The variable sum is initialized to 0, and then the for loop iterates over the range of numbers from 1 to 100. The variable i is assigned each number in the range, and the value of i is added to the sum variable. After the loop has finished executing, the value of sum is printed to the console.
+    """, participant: .system),
+  ]
+
+  static var sample = samples[0]
+}

Diff for: vertexai/ChatSample/Preview Content/Preview Assets.xcassets/Contents.json

@@ -0,0 +1,6 @@
+{
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

Diff for: vertexai/ChatSample/Screens/ConversationScreen.swift

@@ -0,0 +1,129 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import FirebaseVertexAI
+import GenerativeAIUIComponents
+import SwiftUI
+
+struct ConversationScreen: View {
+  @EnvironmentObject
+  var viewModel: ConversationViewModel
+
+  @State
+  private var userPrompt = ""
+
+  enum FocusedField: Hashable {
+    case message
+  }
+
+  @FocusState
+  var focusedField: FocusedField?
+
+  var body: some View {
+    VStack {
+      ScrollViewReader { scrollViewProxy in
+        List {
+          ForEach(viewModel.messages) { message in
+            MessageView(message: message)
+          }
+          if let error = viewModel.error {
+            ErrorView(error: error)
+              .tag("errorView")
+          }
+        }
+        .listStyle(.plain)
+        .onChange(of: viewModel.messages, perform: { newValue in
+          if viewModel.hasError {
+            // wait for a short moment to make sure we can actually scroll to the bottom
+            DispatchQueue.main.asyncAfter(deadline: .now() + 0.05) {
+              withAnimation {
+                scrollViewProxy.scrollTo("errorView", anchor: .bottom)
+              }
+              focusedField = .message
+            }
+          } else {
+            guard let lastMessage = viewModel.messages.last else { return }
+
+            // wait for a short moment to make sure we can actually scroll to the bottom
+            DispatchQueue.main.asyncAfter(deadline: .now() + 0.05) {
+              withAnimation {
+                scrollViewProxy.scrollTo(lastMessage.id, anchor: .bottom)
+              }
+              focusedField = .message
+            }
+          }
+        })
+      }
+      InputField("Message...", text: $userPrompt) {
+        Image(systemName: viewModel.busy ? "stop.circle.fill" : "arrow.up.circle.fill")
+          .font(.title)
+      }
+      .focused($focusedField, equals: .message)
+      .onSubmit { sendOrStop() }
+    }
+    .toolbar {
+      ToolbarItem(placement: .primaryAction) {
+        Button(action: newChat) {
+          Image(systemName: "square.and.pencil")
+        }
+      }
+    }
+    .navigationTitle("Chat sample")
+    .onAppear {
+      focusedField = .message
+    }
+  }
+
+  private func sendMessage() {
+    Task {
+      let prompt = userPrompt
+      userPrompt = ""
+      await viewModel.sendMessage(prompt, streaming: true)
+    }
+  }
+
+  private func sendOrStop() {
+    focusedField = nil
+
+    if viewModel.busy {
+      viewModel.stop()
+    } else {
+      sendMessage()
+    }
+  }
+
+  private func newChat() {
+    viewModel.startNewChat()
+  }
+}
+
+struct ConversationScreen_Previews: PreviewProvider {
+  struct ContainerView: View {
+    @StateObject var viewModel = ConversationViewModel()
+
+    var body: some View {
+      ConversationScreen()
+        .environmentObject(viewModel)
+        .onAppear {
+          viewModel.messages = ChatMessage.samples
+        }
+    }
+  }
+
+  static var previews: some View {
+    NavigationStack {
+      ConversationScreen()
+    }
+  }
+}