[backend/api] Add note import endpoint

Iceshrimp.Backend/Controllers/Web/SettingsController.cs

@@ -210,6 +210,20 @@ public class SettingsController(
 		return Accepted();
 	}
 
+	[HttpPost("import/notes")]
+	[EnableRateLimiting("imports")]
+	[ProducesResults(HttpStatusCode.OK)]
+	[ProducesErrors(HttpStatusCode.BadRequest)]
+	public async Task ImportNotes(IFormFile file)
+	{
+		var user = HttpContext.GetUserOrFail();
+		
+		if (file.ContentType != "application/json")
+			throw GracefulException.BadRequest("File must be JSON");
+		
+		await importExportSvc.ImportNotesAsync(user, file);
+	}
+
 	private async Task<UserSettings> GetOrInitUserSettings()
 	{
 		var user     = HttpContext.GetUserOrFail();

Iceshrimp.Backend/Core/Services/ImportExportService.cs

@@ -1,7 +1,12 @@
+using System.Text.Json;
+using Iceshrimp.Backend.Controllers.Web.Schemas;
 using Iceshrimp.Backend.Core.Configuration;
 using Iceshrimp.Backend.Core.Database;
 using Iceshrimp.Backend.Core.Database.Tables;
 using Iceshrimp.Backend.Core.Extensions;
+using Iceshrimp.Backend.Core.Middleware;
+using Iceshrimp.MfmSharp;
+using Iceshrimp.Shared.Configuration;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Options;
 using static Iceshrimp.Backend.Core.Federation.ActivityPub.UserResolver;
@@ -14,6 +19,8 @@ public class ImportExportService(
 	IOptions<Config.InstanceSection> instance,
 	CacheService cacheSvc,
 	UserService userSvc,
+	NoteService noteSvc,
+	DriveService driveSvc,
 	ActivityPub.UserResolver userResolver
 ) : IScopedService
 {
@@ -50,4 +57,47 @@ public class ImportExportService(
 
 		await QueryableTimelineExtensions.ResetHeuristicAsync(user, cacheSvc);
 	}
+
+	public async Task ImportNotesAsync(User user, IFormFile file)
+	{
+		var notes = await JsonSerializer.DeserializeAsync<List<ExportNote>>(file.OpenReadStream(), JsonSerialization.Options);
+
+		if (notes == null)
+			throw GracefulException.BadRequest("File is not an Iceshrimp note export");
+
+		notes = notes.Where(p => p is
+		             {
+			             LocalOnly: false,
+			             Poll: null,
+			             RenoteId: null,
+			             ReplyId: null,
+			             Visibility: Note.NoteVisibility.Public or Note.NoteVisibility.Home,
+			             VisibleUserIds: []
+		             })
+		             .OrderByDescending(p => p.Id)
+		             .ToList();
+
+		foreach (var exportNote in notes)
+		{
+			var attachments = new List<DriveFile>();
+			foreach (var exportNoteFile in exportNote.Files)
+			{
+				var attachment = await driveSvc.StoreFileAsync(exportNoteFile.Url, user, exportNoteFile.IsSensitive,
+				                                               exportNoteFile.Comment, exportNoteFile.Type);
+				if (attachment != null) attachments.Add(attachment);
+			}
+
+			var note = new NoteService.NoteCreationData
+			{
+				User        = user,
+				Visibility  = exportNote.Visibility,
+				Text        = exportNote.Text,
+				Cw          = exportNote.Cw,
+				Attachments = attachments.Count != 0 ? attachments : null,
+				CreatedAt   = exportNote.CreatedAt
+			};
+
+			await noteSvc.CreateNoteAsync(note);
+		}
+	}
 }