Add SOS functionality for both online and offline device

.gitignore

@@ -3,6 +3,10 @@
 ##
 ## Get latest from https://github.com/github/gitignore/blob/main/VisualStudio.gitignore
 
+# Project files
+
+SOS/Constants/AppwriteConstants.cs
+
 # User-specific files
 *.rsuser
 *.suo

SOS/App.xaml.cs

@@ -1,17 +1,21 @@
-using SOS.Data;
+using SOS.Business;
 
 namespace SOS;
 
 public partial class App : Application
 {
     public static SettingsRepository SettingsRepo { get; private set; }
 
-    public App(SettingsRepository repo)
+    public static LocationService LocationService { get; private set; }
+
+    public App(SettingsRepository repo, LocationService locationService)
     {
         InitializeComponent();
 
         MainPage = new AppShell();
 
         SettingsRepo = repo;
+
+        LocationService = locationService;
     }
 }

SOS/Business/LocationService.cs

@@ -0,0 +1,53 @@
+namespace SOS.Business
+{
+    public class LocationService
+    {
+        private CancellationTokenSource _cancelTokenSource;
+        private bool _isCheckingLocation;
+
+        public async Task<Dictionary<string, object>> GetCurrentLocation()
+        {
+            try
+            {
+                _isCheckingLocation = true;
+
+                GeolocationRequest request = new GeolocationRequest(GeolocationAccuracy.Best);
+
+                _cancelTokenSource = new CancellationTokenSource();
+
+                Location location = await Geolocation.Default.GetLocationAsync(request, _cancelTokenSource.Token);
+
+                if (location != null)
+                {
+                    _isCheckingLocation = false;
+                    return new()
+                {
+                    { "found", true },
+                    { "latitude", location.Latitude.ToString() },
+                    { "longitude", location.Longitude.ToString() }
+                };
+
+                }
+            }
+            catch (Exception ex)
+            {
+                return new()
+                {
+                    { "found", false },
+                    { "error", ex.Message }
+                };
+            }
+
+            return new()
+            {
+                { "found", false }
+            };
+        }
+
+        public void CancelRequest()
+        {
+            if (_isCheckingLocation && _cancelTokenSource != null && _cancelTokenSource.IsCancellationRequested == false)
+                _cancelTokenSource.Cancel();
+        }
+    }
+}

SOS/Data/SettingsRepository.cs → SOS/Business/SettingsRepository.cs

@@ -1,7 +1,8 @@
-using SOS.Models;
+using SOS.Constants;
+using SOS.Models;
 using SQLite;
 
-namespace SOS.Data
+namespace SOS.Business
 {
     public class SettingsRepository
     {
@@ -14,7 +15,7 @@ public async Task Init()
                 return;
             }
 
-            conn = new SQLiteAsyncConnection(Constants.DatabasePath, Constants.Flags);
+            conn = new SQLiteAsyncConnection(DbConstants.DatabasePath, DbConstants.Flags);
             await conn.CreateTableAsync<SettingsData>();
         }
 

SOS/Data/Constants.cs → SOS/Constants/DbConstants.cs

@@ -1,6 +1,6 @@
-namespace SOS.Data
+namespace SOS.Constants
 {
-    public static class Constants
+    public static class DbConstants
     {
         public const string DatabaseFilename = "SOSSettings.db3";
 

SOS/MainPage.xaml.cs

@@ -1,8 +1,12 @@
-namespace SOS;
+using Newtonsoft.Json;
+using SOS.Helpers;
+using SOS.Models;
+
+namespace SOS;
 
 public partial class MainPage : ContentPage
 {
-	public MainPage()
+    public MainPage()
 	{
 		InitializeComponent();
 
@@ -27,9 +31,70 @@ private async void SOSButtonClicked(object sender, EventArgs e)
             return;
         }
 
-        var settings = settingsDbResponse.SettingsData;
+        SettingsData settings = settingsDbResponse.SettingsData;
+        string phoneNumber = settings.PhoneNumber;
+
         SOSButton.BackgroundColor = Colors.Crimson;
-        await DisplayAlert("Alert", $"Saved number: {settings.PhoneNumber}", "Ok");
+
+        var coordinates = await App.LocationService.GetCurrentLocation();
+        if (coordinates["found"] is false)
+        {
+            await DisplayAlert("Error", "Not able to get location", "Ok");
+            return;
+        }
+
+        string latitude = coordinates["latitude"].ToString();
+        string longitude = coordinates["longitude"].ToString();
+
+        NetworkAccess accessType = Connectivity.Current.NetworkAccess;
+
+        if (accessType != NetworkAccess.Internet)
+        {
+            if (Sms.Default.IsComposeSupported)
+            {
+                string[] recipients = new[] { phoneNumber };
+                string text = $"SOS ALERT:\n\nPlease get help at \n\nCoordinates: {latitude},{longitude}";
+
+                var message = new SmsMessage(text, recipients);
+
+                await Sms.Default.ComposeAsync(message);
+            }
+        }
+        else
+        {
+            var endpoint = $"/v1/functions/{AppwriteConstants.FunctionId}/executions";
+
+            HttpClient client = new HttpClient();
+            client.BaseAddress = new Uri(AppwriteConstants.AppwriteUrl);
+            client.DefaultRequestHeaders.Add("X-Appwrite-Response-Format", "1.0.0");
+            client.DefaultRequestHeaders.Add("X-Appwrite-Project", AppwriteConstants.ProjectId);
+            client.DefaultRequestHeaders.Add("X-Appwrite-Key", AppwriteConstants.ApiKey);
+
+            Dictionary<string, string> requestData = new Dictionary<string, string>();
+            requestData.Add("phoneNumber", settings.PhoneNumber);
+            requestData.Add("latitude", coordinates["latitude"].ToString());
+            requestData.Add("longitude", coordinates["longitude"].ToString());
+
+            var appwriteRequestInput = new Dictionary<string, string>() 
+            {
+                { "data", JsonConvert.SerializeObject(requestData) }
+            };
+            var jsonContent = new StringContent(JsonConvert.SerializeObject(appwriteRequestInput), System.Text.Encoding.UTF8, "application/json");
+
+            var sosResponse = await client.PostAsync(endpoint, jsonContent);
+            var sosResponseContent = await sosResponse.Content.ReadAsStringAsync();
+            var sosResponseData = JsonConvert.DeserializeObject<AppwriteApiResponse>(sosResponseContent);
+
+            var appwriteFunctionResponse = JsonConvert.DeserializeObject<Dictionary<string, object>>(sosResponseData.Response);
+            if (Convert.ToBoolean(appwriteFunctionResponse["sos"]))
+            {
+                await DisplayAlert("Alert", $"Sent SOS Request to {settings.PhoneNumber}", "Ok");
+            }
+            else
+            {
+                await DisplayAlert("Alert", "SOS Message Not Sent", "Ok");
+            }
+        }
         SOSButton.BackgroundColor = Colors.Red;
     }
 }

SOS/MauiProgram.cs

@@ -1,4 +1,4 @@
-using SOS.Data;
+using SOS.Business;
 
 namespace SOS;
 
@@ -16,6 +16,7 @@ public static MauiApp CreateMauiApp()
 			});
 
         builder.Services.AddSingleton<SettingsRepository>();
+		builder.Services.AddSingleton<LocationService>();
 
         return builder.Build();
 	}

SOS/Models/AppwriteApiResponse.cs

@@ -0,0 +1,44 @@
+using Newtonsoft.Json;
+using System.Text.Json.Serialization;
+
+namespace SOS.Models
+{
+    public class AppwriteApiResponse
+    {
+        [JsonProperty("$id")]
+        public string Id { get; set; }
+
+        [JsonProperty("$createdAt")]
+        public DateTime CreatedAt { get; set; }
+
+        [JsonProperty("$updatedAt")]
+        public DateTime UpdatedAt { get; set; }
+
+        [JsonProperty("$permissions")]
+        public List<object> Permissions { get; set; }
+
+        [JsonProperty("functionId")]
+        public string FunctionId { get; set; }
+
+        [JsonProperty("trigger")]
+        public string Trigger { get; set; }
+
+        [JsonProperty("status")]
+        public string Status { get; set; }
+
+        [JsonProperty("statusCode")]
+        public int StatusCode { get; set; }
+
+        [JsonProperty("response")]
+        public string Response { get; set; }
+
+        [JsonProperty("stdout")]
+        public string Stdout { get; set; }
+
+        [JsonProperty("stderr")]
+        public string Stderr { get; set; }
+
+        [JsonProperty("duration")]
+        public double Duration { get; set; }
+    }
+}

SOS/Platforms/Android/AndroidManifest.xml

@@ -3,4 +3,10 @@
 	<application android:allowBackup="true" android:icon="@mipmap/appicon" android:roundIcon="@mipmap/appicon_round" android:supportsRtl="true"></application>
 	<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
 	<uses-permission android:name="android.permission.INTERNET" />
+	<queries>
+		<intent>
+			<action android:name="android.intent.action.VIEW" />
+			<data android:scheme="smsto"/>
+		</intent>
+	</queries>
 </manifest>

SOS/Platforms/Android/MainApplication.cs

@@ -1,6 +1,14 @@
 using Android.App;
 using Android.Runtime;
 
+[assembly: UsesPermission(Android.Manifest.Permission.AccessNetworkState)]
+[assembly: UsesPermission(Android.Manifest.Permission.AccessCoarseLocation)]
+[assembly: UsesPermission(Android.Manifest.Permission.AccessFineLocation)]
+[assembly: UsesFeature("android.hardware.location", Required = false)]
+[assembly: UsesFeature("android.hardware.location.gps", Required = false)]
+[assembly: UsesFeature("android.hardware.location.network", Required = false)]
+[assembly: UsesPermission(Android.Manifest.Permission.AccessBackgroundLocation)]
+
 namespace SOS;
 
 [Application]

SOS/Platforms/MacCatalyst/Info.plist

@@ -26,5 +26,7 @@
 	</array>
 	<key>XSAppIconAssets</key>
 	<string>Assets.xcassets/appicon.appiconset</string>
+	<key>NSLocationWhenInUseUsageDescription</key>
+	<string>Fill in a reason why your app needs access to location.</string>
 </dict>
 </plist>

SOS/Platforms/iOS/Info.plist

@@ -28,5 +28,7 @@
 	</array>
 	<key>XSAppIconAssets</key>
 	<string>Assets.xcassets/appicon.appiconset</string>
+	<key>NSLocationWhenInUseUsageDescription</key>
+	<string>Fill in a reason why your app needs access to location.</string>
 </dict>
 </plist>

SOS/SOS.csproj

@@ -48,6 +48,7 @@
 	</ItemGroup>
 
 	<ItemGroup>
+	  <PackageReference Include="Newtonsoft.Json" Version="13.0.2" />
 	  <PackageReference Include="sqlite-net-pcl" Version="1.8.116" />
 	  <PackageReference Include="SQLitePCLRaw.core" Version="2.1.0" />
 	  <PackageReference Include="SQLitePCLRaw.bundle_green" Version="2.1.0" />