Added the BeyondFacts Lab as a prototype (#1175)

app/MindWork AI Studio/Assistants/BeyondFactsLab/BeyondFactsLabStore.Forms.cs

@@ -0,0 +1,134 @@
+using System.Text.Json;
+
+namespace AIStudio.Assistants.BeyondFactsLab;
+
+public sealed partial class BeyondFactsLabStore
+{
+    /// <summary>
+    /// The folder of a preparation which holds a folder for each step.
+    /// </summary>
+    private const string STEPS_DIRECTORY_NAME = "steps";
+
+    /// <summary>
+    /// The file of a step which holds its form "Your details".
+    /// </summary>
+    private const string FORM_FILE_NAME = "form.json";
+
+    /// <summary>
+    /// Loads the form of a step.
+    /// </summary>
+    /// <param name="projectId">The ID of the preparation.</param>
+    /// <param name="step">The step.</param>
+    /// <param name="token">The cancellation token.</param>
+    /// <returns>The form, or an empty one when the person entered nothing yet.</returns>
+    /// <exception cref="InvalidDataException">This version cannot open the form.</exception>
+    public async Task<BflStepFormData> LoadFormAsync(Guid projectId, BflStep step, CancellationToken token = default)
+    {
+        await this.InitializeAsync(token);
+        return await this.LoadFormWithoutInitializeAsync(projectId, step, token);
+    }
+
+    /// <summary>
+    /// Loads the forms of every step of a preparation, e.g., to find missing details.
+    /// </summary>
+    /// <param name="projectId">The ID of the preparation.</param>
+    /// <param name="token">The cancellation token.</param>
+    /// <returns>The forms this version can open, by their steps.</returns>
+    public async Task<IReadOnlyDictionary<BflStep, BflStepFormData>> LoadFormsAsync(Guid projectId, CancellationToken token = default)
+    {
+        await this.InitializeAsync(token);
+        var forms = new Dictionary<BflStep, BflStepFormData>();
+        foreach (var step in BflStep.All)
+        {
+            try
+            {
+                forms[step] = await this.LoadFormWithoutInitializeAsync(projectId, step, token);
+            }
+            catch (InvalidDataException exception)
+            {
+                logger.LogWarning(exception, "Could not open the form of the step '{Step}' of the preparation '{ProjectId}' of the BeyondFacts Lab.", step, projectId);
+            }
+        }
+
+        return forms;
+    }
+
+    /// <summary>
+    /// Stores the form of a step and counts it as a change of the preparation.
+    /// </summary>
+    /// <param name="projectId">The ID of the preparation.</param>
+    /// <param name="step">The step.</param>
+    /// <param name="form">The form.</param>
+    /// <param name="token">The cancellation token.</param>
+    /// <returns>The preparation with its new time of change.</returns>
+    /// <exception cref="FileNotFoundException">The preparation does not exist.</exception>
+    /// <exception cref="InvalidDataException">This version cannot open the preparation or the stored form, so it does not write them either.</exception>
+    public async Task<BflProject> SaveFormAsync(Guid projectId, BflStep step, BflStepFormData form, CancellationToken token = default)
+    {
+        await this.InitializeAsync(token);
+        var gate = this.GetLock(projectId);
+        await gate.WaitAsync(token);
+        try
+        {
+            var project = await this.LoadRequiredWithoutInitializeAsync(projectId, token);
+
+            // A form which a newer version stored, or which is damaged, stays as it is:
+            await this.LoadFormWithoutInitializeAsync(projectId, step, token);
+
+            form.SchemaVersion = BflStepFormData.CURRENT_SCHEMA_VERSION;
+            await WriteTextAtomicAsync(this.FormPath(projectId, step), JsonSerializer.Serialize(form, JSON_OPTIONS), token);
+
+            project.ModifiedAtUtc = DateTimeOffset.UtcNow;
+            await this.StoreProjectAsync(project, token);
+            return project;
+        }
+        finally
+        {
+            gate.Release();
+        }
+    }
+
+    /// <summary>
+    /// Reads the form of a step without the first start of the store.
+    /// </summary>
+    /// <param name="projectId">The ID of the preparation.</param>
+    /// <param name="step">The step.</param>
+    /// <param name="token">The cancellation token.</param>
+    /// <returns>The form, or an empty one when there is no file.</returns>
+    /// <exception cref="InvalidDataException">This version cannot open the form.</exception>
+    private async Task<BflStepFormData> LoadFormWithoutInitializeAsync(Guid projectId, BflStep step, CancellationToken token)
+    {
+        var path = this.FormPath(projectId, step);
+        if (!File.Exists(path))
+            return new BflStepFormData();
+
+        BflStepFormData? form;
+        try
+        {
+            await using var stream = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read, 65_536, true);
+            form = await JsonSerializer.DeserializeAsync<BflStepFormData>(stream, JSON_OPTIONS, token);
+        }
+        catch (Exception exception) when (exception is IOException or UnauthorizedAccessException or JsonException)
+        {
+            throw new InvalidDataException("This version of AI Studio cannot open the form.", exception);
+        }
+
+        if (form is null || form.SchemaVersion is < 1 or > BflStepFormData.CURRENT_SCHEMA_VERSION || IsNull(form.Values))
+            throw new InvalidDataException("This version of AI Studio cannot open the form.");
+
+        return form;
+    }
+
+    /// <summary>
+    /// Gets the file of the form of a step.
+    /// </summary>
+    /// <param name="projectId">The ID of the preparation.</param>
+    /// <param name="step">The step.</param>
+    private string FormPath(Guid projectId, BflStep step) => Path.Combine(this.ProjectDirectory(projectId), STEPS_DIRECTORY_NAME, step.FolderName, FORM_FILE_NAME);
+
+    /// <summary>
+    /// Checks for null a value which the type system says cannot be null, but which JSON can make null.
+    /// </summary>
+    /// <param name="value">The value.</param>
+    private static bool IsNull<T>(T? value) => value is null;
+}