Add flashcards feature with spaced repetition scheduling

Adds a full flashcards system: FSRS-based scheduling, cloze/basic card types, CSV import/export, media storage, and study UI, wired into navigation and the dashboard alongside existing question flows.
2026-07-21 15:08:52 -05:00
parent 29b89dc404
commit 48a8c8361d
41 changed files with 4458 additions and 8 deletions
@@ -0,0 +1,92 @@
+using System.Text.Json;
+using QuestionsApi.Models;
+using QuestionsApi.Services.Flashcards;
+using Xunit;
+
+namespace QuestionsApi.Tests;
+
+public sealed class FlashcardImportExportModelTests
+{
+    [Fact]
+    public void JsonExport_RoundTrips_NotesCardsAndReviewHistory()
+    {
+        var export = new FlashcardJsonExport
+        {
+            SchemaVersion = 1,
+            Settings = new FlashcardSettings { UserId = "user-1", NewCardsPerDay = 20, ReviewsPerDay = 200 },
+            Decks = [new FlashcardDeck { Id = "deck-1", UserId = "user-1", Name = "Cardio", IsDefault = true }],
+            Notes =
+            [
+                new FlashcardJsonExportNote
+                {
+                    Note = new FlashcardNote
+                    {
+                        Id = "note-1", UserId = "user-1", DeckId = "deck-1", StableId = "stable-1",
+                        Type = FlashcardTypes.Cloze, Prompt = "{{c1::Paris}} is the capital of France",
+                        Tags = ["geography"]
+                    },
+                    Cards =
+                    [
+                        new FlashcardSchedule
+                        {
+                            Id = "card-1", UserId = "user-1", NoteId = "note-1", Variant = 1,
+                            State = FlashcardScheduleStates.Review, Stability = 12.3, Difficulty = 4.5,
+                            DueUtc = new DateTime(2026, 1, 1, 0, 0, 0, DateTimeKind.Utc)
+                        }
+                    ],
+                    ReviewLogs =
+                    [
+                        new FlashcardReviewLog
+                        {
+                            Id = "log-1", UserId = "user-1", CardId = "card-1", Rating = FlashcardRatings.Good,
+                            ReviewedUtc = new DateTime(2025, 12, 31, 0, 0, 0, DateTimeKind.Utc)
+                        }
+                    ],
+                    Images = [new FlashcardJsonExportImage { AssetId = "asset-1", FileName = "x.png", ContentType = "image/png", Base64Bytes = Convert.ToBase64String([1, 2, 3]) }]
+                }
+            ]
+        };
+
+        var json = JsonSerializer.Serialize(export);
+        var roundTripped = JsonSerializer.Deserialize<FlashcardJsonExport>(json);
+
+        Assert.NotNull(roundTripped);
+        var note = Assert.Single(roundTripped!.Notes);
+        Assert.Equal("stable-1", note.Note.StableId);
+        Assert.Equal(FlashcardTypes.Cloze, note.Note.Type);
+        var card = Assert.Single(note.Cards);
+        Assert.Equal(1, card.Variant);
+        Assert.Equal(12.3, card.Stability);
+        var log = Assert.Single(note.ReviewLogs);
+        Assert.Equal(FlashcardRatings.Good, log.Rating);
+        var image = Assert.Single(note.Images);
+        Assert.Equal([1, 2, 3], Convert.FromBase64String(image.Base64Bytes));
+    }
+
+    [Fact]
+    public void Fingerprint_IsStable_ForSameTypePromptAndAnswer_IgnoringSurroundingWhitespace()
+    {
+        var a = FlashcardNoteStore.Fingerprint(FlashcardTypes.Basic, "  What is 2+2?  ", "4");
+        var b = FlashcardNoteStore.Fingerprint(FlashcardTypes.Basic, "What is 2+2?", "4");
+
+        Assert.Equal(a, b);
+    }
+
+    [Fact]
+    public void Fingerprint_DiffersWhenAnswerDiffers()
+    {
+        var a = FlashcardNoteStore.Fingerprint(FlashcardTypes.Basic, "What is 2+2?", "4");
+        var b = FlashcardNoteStore.Fingerprint(FlashcardTypes.Basic, "What is 2+2?", "five");
+
+        Assert.NotEqual(a, b);
+    }
+
+    [Fact]
+    public void Fingerprint_DiffersByType_ForSamePromptAndAnswer()
+    {
+        var basic = FlashcardNoteStore.Fingerprint(FlashcardTypes.Basic, "text", "text");
+        var cloze = FlashcardNoteStore.Fingerprint(FlashcardTypes.Cloze, "text", "text");
+
+        Assert.NotEqual(basic, cloze);
+    }
+}