1 files changed, 50 insertions, 0 deletions
diff --git a/TtsService.cs b/TtsService.cs
new file mode 100644
index 0000000..8d0a146
--- /dev/null
+++ b/TtsService.cs
@@ -0,0 +1,50 @@
+namespace PagerParser;
+
+public interface ITtsService {
+    public string GetTtsMessage(ParsedPagerMessage pm);
+}
+
+public class TtsService : ITtsService {
+    public static readonly Dictionary<string, string> IncidentTypeMap = new() {
+        { "ALAR", "FIRE ALARM"        },
+        { "G&S",  "GRASS & SCRUB"     },
+        { "HIAR", "HIGH-ANGLE RESCUE" },
+        { "INCI", "INCIDENT"          },
+        { "NOST", "NON-STRUCTURE"     },
+        { "RESC", "RESCUE"            },
+        { "STRU", "STRUCTURE"         }
+    };
+
+    private List<Landmark> landmarks;
+
+    public TtsService(IConfiguration config) =>
+        config.Bind("PagerParser:Landmarks", landmarks);
+
+    public string GetTtsMessage(ParsedPagerMessage pm) {
+        // If we have GPS coordinates for the page, check if
+        // it's near a well-known landmark and include that
+        // in the TTS message.
+        string? nearestLandmark = null;
+        if(pm.GpsPosition is not null)
+            nearestLandmark = landmarks
+                .Where(l => pm.GpsPosition.GetDistance(l.Latitude, l.Longitude) < l.Radius)
+                .OrderBy(l => pm.GpsPosition.GetDistance(l.Latitude, l.Longitude))
+                .Select(l => l.Name)
+                .FirstOrDefault();
+
+        return string.Join(" ", [
+            IncidentTypeMap.GetValueOrDefault(pm.JobType) ?? "UNKNOWN ALERT",
+            pm.Description,
+            nearestLandmark is null ? null : $"located near {nearestLandmark}",
+            // TODO: more detailed information on what services have been paged
+            pm.PagedServices.Count > 0 ? $"{pm.PagedServices.Count} services paged" : null
+            ]).Trim();
+    }
+}
+
+public record Landmark {
+    public string Name      { get; set; }
+    public double Latitude  { get; set; }
+    public double Longitude { get; set; }
+    public double Radius    { get; set; }
+}