feat: Integrate Geoapify geocoding service and update configuration

1 files changed, 110 insertions, 0 deletions

diff --git a/src/Enmarcha.Backend/Services/Geocoding/GeoapifyGeocodingService.cs b/src/Enmarcha.Backend/Services/Geocoding/GeoapifyGeocodingService.cs
new file mode 100644
index 0000000..d6cf5f6
--- /dev/null
+++ b/src/Enmarcha.Backend/Services/Geocoding/GeoapifyGeocodingService.cs
@@ -0,0 +1,110 @@
+using System.Globalization;
+using Enmarcha.Backend.Configuration;
+using Enmarcha.Backend.Types.Geoapify;
+using Enmarcha.Backend.Types.Planner;
+using Microsoft.Extensions.Caching.Memory;
+using Microsoft.Extensions.Options;
+
+namespace Enmarcha.Backend.Services.Geocoding;
+
+public class GeoapifyGeocodingService : IGeocodingService
+{
+    private readonly HttpClient _httpClient;
+    private readonly IMemoryCache _cache;
+    private readonly ILogger<GeoapifyGeocodingService> _logger;
+    private readonly AppConfiguration _config;
+
+    private static readonly string[] ForbiddenResultTypes = ["city", "state", "county", "postcode"];
+
+    public GeoapifyGeocodingService(HttpClient httpClient, IMemoryCache cache, ILogger<GeoapifyGeocodingService> logger, IOptions<AppConfiguration> config)
+    {
+        _httpClient = httpClient;
+        _cache = cache;
+        _logger = logger;
+        _config = config.Value;
+
+        // Geoapify requires a User-Agent
+        if (!_httpClient.DefaultRequestHeaders.Contains("User-Agent"))
+        {
+            _httpClient.DefaultRequestHeaders.Add("User-Agent", "Mozilla/5.0 (Compatible; Enmarcha/0.1; https://enmarcha.app; ariel@costas.dev)");
+        }
+    }
+
+    public async Task<List<PlannerSearchResult>> GetAutocompleteAsync(string query)
+    {
+        if (string.IsNullOrWhiteSpace(query))
+        {
+            return [];
+        }
+
+        var cacheKey = $"nominatim_autocomplete_{query.ToLowerInvariant()}";
+        if (_cache.TryGetValue(cacheKey, out List<PlannerSearchResult>? cachedResults) && cachedResults != null)
+        {
+            return cachedResults;
+        }
+
+        var url = $"https://api.geoapify.com/v1/geocode/autocomplete?text={Uri.EscapeDataString(query)}&lang=gl&limit=5&filter=rect:-9.449497230816405,41.89720361654395,-6.581039728137625,43.92616367306067&format=json";
+
+        try
+        {
+            var response = await _httpClient.GetFromJsonAsync<GeoapifyResult>(url + $"&apiKey={_config.GeoapifyApiKey}");
+
+
+            var results = response?.results
+                .Where(x => !ForbiddenResultTypes.Contains(x.result_type))
+                .Select(MapToPlannerSearchResult)
+                .ToList() ?? [];
+
+            _cache.Set(cacheKey, results, TimeSpan.FromMinutes(60));
+            return results;
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Error fetching Geoapify autocomplete results from {Url}", url);
+            return new List<PlannerSearchResult>();
+        }
+    }
+
+    public async Task<PlannerSearchResult?> GetReverseGeocodeAsync(double lat, double lon)
+    {
+        var cacheKey = $"nominatim_reverse_{lat:F5}_{lon:F5}";
+        if (_cache.TryGetValue(cacheKey, out PlannerSearchResult? cachedResult) && cachedResult != null)
+        {
+            return cachedResult;
+        }
+
+        var url =
+            $"https://api.geoapify.com/v1/geocode/reverse?lat={lat.ToString(CultureInfo.InvariantCulture)}&lon={lon.ToString(CultureInfo.InvariantCulture)}&lang=gl&format=json";
+        try
+        {
+            var response = await _httpClient.GetFromJsonAsync<GeoapifyResult>(url + $"&apiKey={_config.GeoapifyApiKey}");
+
+            if (response == null) return null;
+
+            var result = MapToPlannerSearchResult(response.results[0]);
+
+            _cache.Set(cacheKey, result, TimeSpan.FromMinutes(60));
+            return result;
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Error fetching Geoapify reverse geocode results from {Url}", url);
+            return null;
+        }
+    }
+
+    private PlannerSearchResult MapToPlannerSearchResult(Result result)
+    {
+        var name = result.name ?? result.address_line1;
+        var label = $"{result.street} ({result.postcode} {result.city}, {result.county})";
+
+        return new PlannerSearchResult
+        {
+            Name = name,
+            Label = label,
+            Lat = result.lat,
+            Lon = result.lon,
+            Layer = result.result_type
+        };
+    }
+}