feat: add learning activity endpoints

Tiku.Infrastructure/DependencyInjection.cs

@@ -5,6 +5,7 @@ using Tiku.Application.Assets;
 using Tiku.Application.Auth;
 using Tiku.Application.Catalog;
 using Tiku.Application.Content;
+using Tiku.Application.Learning;
 using Tiku.Application.QuestionBanks;
 using Tiku.Application.Storage;
 using Tiku.Application.StudyContent;
@@ -12,6 +13,7 @@ using Tiku.Infrastructure.Assets;
 using Tiku.Infrastructure.Auth;
 using Tiku.Infrastructure.Catalog;
 using Tiku.Infrastructure.Content;
+using Tiku.Infrastructure.Learning;
 using Tiku.Infrastructure.Persistence;
 using Tiku.Infrastructure.QuestionBanks;
 using Tiku.Infrastructure.Storage;
@@ -46,6 +48,7 @@ public static class DependencyInjection
         services.AddScoped<IStudyContentQueryService, StudyContentQueryService>();
         services.AddScoped<IAssetQueryService, AssetQueryService>();
         services.AddScoped<IAssetAccessService, AssetAccessService>();
+        services.AddScoped<ILearningActivityService, LearningActivityService>();
         services.AddOptions<AliyunOssOptions>()
             .Validate(
                 AliyunOssOptions.BeValid,

Tiku.Infrastructure/Learning/LearningActivityService.cs

@@ -0,0 +1,477 @@
+using Microsoft.EntityFrameworkCore;
+using System.Text.Json;
+using Tiku.Application.Learning;
+using Tiku.Domain.Content;
+using Tiku.Domain.Learning;
+using Tiku.Domain.QuestionBanks;
+using Tiku.Infrastructure.Persistence;
+
+namespace Tiku.Infrastructure.Learning;
+
+public sealed class LearningActivityService(TikuDbContext dbContext) : ILearningActivityService
+{
+    private const int DefaultLimit = 100;
+    private const int MaxLimit = 500;
+
+    public async Task<AnswerRecordItem> SubmitAnswerAsync(
+        LearningActor actor,
+        SubmitAnswerCommand command,
+        CancellationToken cancellationToken = default)
+    {
+        var question = await dbContext.Questions
+            .AsNoTracking()
+            .Where(item =>
+                item.TenantId == actor.TenantId &&
+                item.Id == command.QuestionId &&
+                item.Status == QuestionStatus.Published)
+            .Select(item => new
+            {
+                item.Id,
+                item.CurrentVersionId
+            })
+            .SingleOrDefaultAsync(cancellationToken);
+
+        if (question is null)
+        {
+            throw new LearningResourceNotFoundException("question_not_found", "Question was not found.");
+        }
+
+        if (command.PracticeSessionId.HasValue)
+        {
+            var sessionExists = await dbContext.PracticeSessions.AnyAsync(
+                session =>
+                    session.TenantId == actor.TenantId &&
+                    session.UserId == actor.UserId &&
+                    session.Id == command.PracticeSessionId.Value,
+                cancellationToken);
+
+            if (!sessionExists)
+            {
+                throw new LearningResourceNotFoundException("practice_session_not_found", "Practice session was not found.");
+            }
+        }
+
+        var now = DateTimeOffset.UtcNow;
+        var record = new AnswerRecord
+        {
+            TenantId = actor.TenantId,
+            UserId = actor.UserId,
+            QuestionId = question.Id,
+            QuestionVersionId = question.CurrentVersionId,
+            PracticeSessionId = command.PracticeSessionId,
+            SelectedOptions = JsonSerializer.SerializeToElement(command.SelectedOptions ?? []),
+            AnswerText = command.AnswerText,
+            IsCorrect = command.SelfJudgedCorrect,
+            AnsweredAt = now,
+            CreatedAt = now
+        };
+        dbContext.AnswerRecords.Add(record);
+
+        if (command.SelfJudgedCorrect == false)
+        {
+            var wrongQuestion = await dbContext.WrongQuestions.FindAsync(
+                [actor.TenantId, actor.UserId, question.Id],
+                cancellationToken);
+
+            if (wrongQuestion is null)
+            {
+                dbContext.WrongQuestions.Add(new WrongQuestion
+                {
+                    TenantId = actor.TenantId,
+                    UserId = actor.UserId,
+                    QuestionId = question.Id,
+                    WrongCount = 1,
+                    LastWrongAt = now
+                });
+            }
+            else
+            {
+                wrongQuestion.WrongCount++;
+                wrongQuestion.LastWrongAt = now;
+                wrongQuestion.ResolvedAt = null;
+            }
+        }
+
+        await dbContext.SaveChangesAsync(cancellationToken);
+        return ToItem(record);
+    }
+
+    public async Task<LearningList<FavoriteQuestionItem>> GetFavoriteQuestionsAsync(
+        LearningActor actor,
+        LearningLimitFilter filter,
+        CancellationToken cancellationToken = default)
+    {
+        var items = await dbContext.FavoriteQuestions
+            .AsNoTracking()
+            .Where(item =>
+                item.TenantId == actor.TenantId &&
+                item.UserId == actor.UserId)
+            .OrderByDescending(item => item.CreatedAt)
+            .Take(ResolveLimit(filter.Limit))
+            .Select(item => new FavoriteQuestionItem(
+                item.QuestionId,
+                item.Source,
+                item.CreatedAt))
+            .ToArrayAsync(cancellationToken);
+
+        return new LearningList<FavoriteQuestionItem>(items);
+    }
+
+    public async Task<LearningActionResult> ToggleFavoriteQuestionAsync(
+        LearningActor actor,
+        QuestionActionCommand command,
+        CancellationToken cancellationToken = default)
+    {
+        await EnsureQuestionExistsAsync(actor.TenantId, command.QuestionId, cancellationToken);
+
+        var favorite = command.Favorite ?? true;
+        var item = await dbContext.FavoriteQuestions.FindAsync(
+            [actor.TenantId, actor.UserId, command.QuestionId],
+            cancellationToken);
+
+        if (favorite)
+        {
+            if (item is null)
+            {
+                dbContext.FavoriteQuestions.Add(new FavoriteQuestion
+                {
+                    TenantId = actor.TenantId,
+                    UserId = actor.UserId,
+                    QuestionId = command.QuestionId,
+                    Source = "api",
+                    CreatedAt = DateTimeOffset.UtcNow
+                });
+            }
+        }
+        else if (item is not null)
+        {
+            dbContext.FavoriteQuestions.Remove(item);
+        }
+
+        await dbContext.SaveChangesAsync(cancellationToken);
+        return new LearningActionResult(true, favorite);
+    }
+
+    public async Task<LearningList<WrongQuestionItem>> GetWrongQuestionsAsync(
+        LearningActor actor,
+        LearningLimitFilter filter,
+        CancellationToken cancellationToken = default)
+    {
+        var query = dbContext.WrongQuestions
+            .AsNoTracking()
+            .Where(item =>
+                item.TenantId == actor.TenantId &&
+                item.UserId == actor.UserId);
+
+        if (!string.Equals(filter.Status, "all", StringComparison.OrdinalIgnoreCase))
+        {
+            query = query.Where(item => item.ResolvedAt == null);
+        }
+
+        var items = await query
+            .OrderByDescending(item => item.LastWrongAt)
+            .Take(ResolveLimit(filter.Limit))
+            .Select(item => new WrongQuestionItem(
+                item.QuestionId,
+                item.WrongCount,
+                item.LastWrongAt,
+                item.ResolvedAt))
+            .ToArrayAsync(cancellationToken);
+
+        return new LearningList<WrongQuestionItem>(items);
+    }
+
+    public async Task<LearningActionResult> ResolveWrongQuestionAsync(
+        LearningActor actor,
+        QuestionActionCommand command,
+        CancellationToken cancellationToken = default)
+    {
+        var item = await dbContext.WrongQuestions.FindAsync(
+            [actor.TenantId, actor.UserId, command.QuestionId],
+            cancellationToken);
+
+        if (item is null)
+        {
+            throw new LearningResourceNotFoundException("wrong_question_not_found", "Wrong question was not found.");
+        }
+
+        item.ResolvedAt = DateTimeOffset.UtcNow;
+        await dbContext.SaveChangesAsync(cancellationToken);
+        return new LearningActionResult(true);
+    }
+
+    public async Task<LearningList<WordProgressItem>> GetWordProgressAsync(
+        LearningActor actor,
+        LearningLimitFilter filter,
+        CancellationToken cancellationToken = default)
+    {
+        var query = dbContext.UserWordProgress
+            .AsNoTracking()
+            .Where(item =>
+                item.TenantId == actor.TenantId &&
+                item.UserId == actor.UserId);
+
+        if (filter.UnitId.HasValue)
+        {
+            query = query.Where(item => dbContext.VocabularyWords.Any(word =>
+                word.TenantId == actor.TenantId &&
+                word.Id == item.WordId &&
+                word.UnitId == filter.UnitId.Value));
+        }
+
+        if (TryParseWordProgressStatus(filter.Status, out var status))
+        {
+            query = query.Where(item => item.Status == status);
+        }
+
+        var items = await query
+            .OrderBy(item => item.NextReviewAt == null)
+            .ThenBy(item => item.NextReviewAt)
+            .ThenByDescending(item => item.UpdatedAt)
+            .Take(ResolveLimit(filter.Limit))
+            .Select(item => new WordProgressItem(
+                item.WordId,
+                item.Status,
+                item.CorrectCount,
+                item.WrongCount,
+                item.LastReviewAt,
+                item.NextReviewAt,
+                item.ReviewCount,
+                item.CorrectStreak,
+                item.LastResult,
+                item.DueLevel,
+                item.Metadata))
+            .ToArrayAsync(cancellationToken);
+
+        return new LearningList<WordProgressItem>(items);
+    }
+
+    public async Task<WordProgressItem> UpdateWordProgressAsync(
+        LearningActor actor,
+        WordProgressCommand command,
+        CancellationToken cancellationToken = default)
+    {
+        await EnsureWordExistsAsync(actor.TenantId, command.WordId, cancellationToken);
+
+        var now = DateTimeOffset.UtcNow;
+        var item = await dbContext.UserWordProgress
+            .SingleOrDefaultAsync(
+                progress =>
+                    progress.TenantId == actor.TenantId &&
+                    progress.UserId == actor.UserId &&
+                    progress.WordId == command.WordId,
+                cancellationToken);
+
+        if (item is null)
+        {
+            item = new UserWordProgress
+            {
+                TenantId = actor.TenantId,
+                UserId = actor.UserId,
+                WordId = command.WordId
+            };
+            dbContext.UserWordProgress.Add(item);
+        }
+
+        if (TryParseWordProgressStatus(command.Status, out var status))
+        {
+            item.Status = status;
+        }
+        else if (string.IsNullOrWhiteSpace(command.Status))
+        {
+            item.Status = WordProgressStatus.Learning;
+        }
+        else
+        {
+            throw new LearningValidationException("invalid_word_status", "Word progress status is invalid.");
+        }
+
+        var correctDelta = command.CorrectDelta ?? 0;
+        var wrongDelta = command.WrongDelta ?? 0;
+        item.CorrectCount += correctDelta;
+        item.WrongCount += wrongDelta;
+        item.ReviewCount += correctDelta + wrongDelta;
+        item.CorrectStreak = wrongDelta > 0
+            ? 0
+            : item.CorrectStreak + correctDelta;
+        item.LastResult = wrongDelta > 0
+            ? WordReviewResult.Wrong
+            : correctDelta > 0
+                ? WordReviewResult.Correct
+                : item.LastResult;
+        item.LastReviewAt = correctDelta + wrongDelta > 0 ? now : item.LastReviewAt;
+        item.NextReviewAt = command.NextReviewAt ?? item.NextReviewAt;
+        item.DueLevel = item.Status == WordProgressStatus.Mastered
+            ? WordDueLevel.Mastered
+            : item.WrongCount > 0 && item.CorrectStreak == 0
+                ? WordDueLevel.Again
+                : item.DueLevel;
+
+        await dbContext.SaveChangesAsync(cancellationToken);
+        return ToItem(item);
+    }
+
+    public async Task<LearningList<FavoriteWordItem>> GetFavoriteWordsAsync(
+        LearningActor actor,
+        LearningLimitFilter filter,
+        CancellationToken cancellationToken = default)
+    {
+        var query = dbContext.UserWordFavorites
+            .AsNoTracking()
+            .Where(item =>
+                item.TenantId == actor.TenantId &&
+                item.UserId == actor.UserId);
+
+        if (filter.UnitId.HasValue)
+        {
+            query = query.Where(item => dbContext.VocabularyWords.Any(word =>
+                word.TenantId == actor.TenantId &&
+                word.Id == item.WordId &&
+                word.UnitId == filter.UnitId.Value));
+        }
+
+        var items = await query
+            .OrderByDescending(item => item.FavoritedAt ?? item.CreatedAt)
+            .Take(ResolveLimit(filter.Limit))
+            .Select(item => new FavoriteWordItem(
+                item.WordId,
+                item.Note,
+                item.FavoritedAt))
+            .ToArrayAsync(cancellationToken);
+
+        return new LearningList<FavoriteWordItem>(items);
+    }
+
+    public async Task<LearningActionResult> ToggleFavoriteWordAsync(
+        LearningActor actor,
+        FavoriteWordCommand command,
+        CancellationToken cancellationToken = default)
+    {
+        await EnsureWordExistsAsync(actor.TenantId, command.WordId, cancellationToken);
+
+        var favorite = command.Favorite ?? true;
+        var item = await dbContext.UserWordFavorites
+            .SingleOrDefaultAsync(
+                favoriteWord =>
+                    favoriteWord.TenantId == actor.TenantId &&
+                    favoriteWord.UserId == actor.UserId &&
+                    favoriteWord.WordId == command.WordId,
+                cancellationToken);
+
+        if (favorite)
+        {
+            if (item is null)
+            {
+                item = new UserWordFavorite
+                {
+                    TenantId = actor.TenantId,
+                    UserId = actor.UserId,
+                    WordId = command.WordId
+                };
+                dbContext.UserWordFavorites.Add(item);
+            }
+
+            item.Note = command.Note ?? item.Note;
+            item.FavoritedAt ??= DateTimeOffset.UtcNow;
+        }
+        else if (item is not null)
+        {
+            dbContext.UserWordFavorites.Remove(item);
+        }
+
+        await dbContext.SaveChangesAsync(cancellationToken);
+        return new LearningActionResult(true, favorite);
+    }
+
+    private async Task EnsureQuestionExistsAsync(
+        Guid tenantId,
+        Guid questionId,
+        CancellationToken cancellationToken)
+    {
+        var exists = await dbContext.Questions.AnyAsync(
+            question =>
+                question.TenantId == tenantId &&
+                question.Id == questionId &&
+                question.Status == QuestionStatus.Published,
+            cancellationToken);
+
+        if (!exists)
+        {
+            throw new LearningResourceNotFoundException("question_not_found", "Question was not found.");
+        }
+    }
+
+    private async Task EnsureWordExistsAsync(
+        Guid tenantId,
+        Guid wordId,
+        CancellationToken cancellationToken)
+    {
+        var exists = await dbContext.VocabularyWords.AnyAsync(
+            word =>
+                word.TenantId == tenantId &&
+                word.Id == wordId &&
+                word.IsActive,
+            cancellationToken);
+
+        if (!exists)
+        {
+            throw new LearningResourceNotFoundException("word_not_found", "Word was not found.");
+        }
+    }
+
+    private static AnswerRecordItem ToItem(AnswerRecord record)
+    {
+        return new AnswerRecordItem(
+            record.Id,
+            record.QuestionId!.Value,
+            record.QuestionVersionId,
+            record.PracticeSessionId,
+            record.SelectedOptions,
+            record.AnswerText,
+            record.IsCorrect,
+            record.AnsweredAt);
+    }
+
+    private static WordProgressItem ToItem(UserWordProgress item)
+    {
+        return new WordProgressItem(
+            item.WordId,
+            item.Status,
+            item.CorrectCount,
+            item.WrongCount,
+            item.LastReviewAt,
+            item.NextReviewAt,
+            item.ReviewCount,
+            item.CorrectStreak,
+            item.LastResult,
+            item.DueLevel,
+            item.Metadata);
+    }
+
+    private static bool TryParseWordProgressStatus(string? value, out WordProgressStatus status)
+    {
+        return Enum.TryParse(NormalizeEnumValue(value), ignoreCase: true, out status);
+    }
+
+    private static int ResolveLimit(int? limit)
+    {
+        return Math.Clamp(limit ?? DefaultLimit, 1, MaxLimit);
+    }
+
+    private static string? NormalizeEnumValue(string? value)
+    {
+        return string.IsNullOrWhiteSpace(value)
+            ? null
+            : value.Replace("_", string.Empty, StringComparison.Ordinal)
+                .Replace("-", string.Empty, StringComparison.Ordinal);
+    }
+}
+
+public class LearningException(string code, string message) : Exception(message)
+{
+    public string Code { get; } = code;
+}
+
+public sealed class LearningResourceNotFoundException(string code, string message) : LearningException(code, message);
+
+public sealed class LearningValidationException(string code, string message) : LearningException(code, message);