Add lyrics prefetch endpoint and UI button: prefetch lyrics for individual playlists with progress feedback

allstarr/Controllers/AdminController.cs

@@ -38,6 +38,7 @@ public class AdminController : ControllerBase
     private readonly RedisCacheService _cache;
     private readonly HttpClient _jellyfinHttpClient;
     private readonly IWebHostEnvironment _environment;
+    private readonly IServiceProvider _serviceProvider;
     private readonly string _envFilePath;
     private const string CacheDirectory = "/app/cache/spotify";
     
@@ -56,6 +57,7 @@ public class AdminController : ControllerBase
         SpotifyPlaylistFetcher playlistFetcher,
         RedisCacheService cache,
         IHttpClientFactory httpClientFactory,
+        IServiceProvider serviceProvider,
         SpotifyTrackMatchingService? matchingService = null)
     {
         _logger = logger;
@@ -73,6 +75,7 @@ public class AdminController : ControllerBase
         _matchingService = matchingService;
         _cache = cache;
         _jellyfinHttpClient = httpClientFactory.CreateClient();
+        _serviceProvider = serviceProvider;
         
         // .env file path is always /app/.env in Docker (mounted from host)
         // In development, it's in the parent directory of ContentRootPath
@@ -2621,6 +2624,46 @@ public class AdminController : ControllerBase
         }
     }
     
+    /// <summary>
+    /// Prefetch lyrics for a specific playlist
+    /// </summary>
+    [HttpPost("playlists/{name}/prefetch-lyrics")]
+    public async Task<IActionResult> PrefetchPlaylistLyrics(string name)
+    {
+        var decodedName = Uri.UnescapeDataString(name);
+        
+        try
+        {
+            var lyricsPrefetchService = _serviceProvider.GetService<allstarr.Services.Lyrics.LyricsPrefetchService>();
+            
+            if (lyricsPrefetchService == null)
+            {
+                return StatusCode(500, new { error = "Lyrics prefetch service not available" });
+            }
+            
+            _logger.LogInformation("Starting lyrics prefetch for playlist: {Playlist}", decodedName);
+            
+            var (fetched, cached, missing) = await lyricsPrefetchService.PrefetchPlaylistLyricsAsync(
+                decodedName, 
+                HttpContext.RequestAborted);
+            
+            return Ok(new
+            {
+                message = "Lyrics prefetch complete",
+                playlist = decodedName,
+                fetched,
+                cached,
+                missing,
+                total = fetched + cached + missing
+            });
+        }
+        catch (Exception ex)
+        {
+            _logger.LogError(ex, "Failed to prefetch lyrics for playlist {Playlist}", decodedName);
+            return StatusCode(500, new { error = $"Failed to prefetch lyrics: {ex.Message}" });
+        }
+    }
+    
     #endregion
 }