Take screenshot

// Copyright 2025 Esri
//
// 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
//
//   https://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 ArcGIS
import SwiftUI

struct TakeScreenshotView: View {
    /// The current draw status of the map.
    @State private var currentDrawStatus: DrawStatus = .inProgress
    /// The screenshot to export.
    @State private var screenshot: Screenshot?
    /// The map with an imagery basemap centered on Hawaii.
    @State private var map: Map = {
        let map = Map(basemapStyle: .arcGISImageryStandard)
        map.initialViewpoint = Viewpoint(
            latitude: 20.78,
            longitude: -156.84,
            scale: 5_000_000
        )
        return map
    }()

    var body: some View {
        MapViewReader { mapViewProxy in
            MapView(map: map)
                .onDrawStatusChanged { drawStatus in
                    withAnimation {
                        currentDrawStatus = drawStatus
                    }
                }
                .sheet(item: $screenshot) { screenshot in
                    NavigationStack {
                        ShareScreenshotView(screenshot: screenshot)
                    }
                }
                .toolbar {
                    ToolbarItem(placement: .bottomBar) {
                        Button {
                            Task {
                                // The map view proxy is used to export a
                                // screenshot of the map view.
                                let image = try await mapViewProxy.exportImage()
                                screenshot = Screenshot(
                                    image: Image(uiImage: image),
                                    caption: "A screenshot of the map."
                                )
                            }
                        } label: {
                            if currentDrawStatus != .completed {
                                ProgressView()
                                    .progressViewStyle(.circular)
                            }
                            Text("Take Screenshot")
                        }
                        .disabled(currentDrawStatus != .completed)
                    }
                }
        }
    }
}

private extension TakeScreenshotView {
    /// A struct that represents a screenshot with a caption to be shared.
    struct Screenshot: Transferable, Identifiable {
        static var transferRepresentation: some TransferRepresentation {
            ProxyRepresentation(exporting: \.image)
        }

        let id = UUID()
        let image: Image
        let caption: String
    }

    /// A view that displays an image to be shared.
    struct ShareScreenshotView: View {
        /// The action to dismiss the sheet.
        @Environment(\.dismiss) private var dismiss: DismissAction
        /// The screenshot to display.
        let screenshot: Screenshot

        var body: some View {
            screenshot.image
                .resizable()
                .aspectRatio(contentMode: .fit)
                .toolbar {
                    ToolbarItem(placement: .confirmationAction) {
                        Button("Done") {
                            dismiss()
                        }
                    }

                    ToolbarItem(placement: .navigationBarTrailing) {
                        // A share link to share the screenshot image.
                        ShareLink(
                            item: screenshot,
                            preview: SharePreview(
                                screenshot.caption,
                                image: screenshot.image
                            )
                        )
                    }
                }
        }
    }
}

#Preview {
    TakeScreenshotView()
}