feature: Self-Service Clinical Testing Sessions

VigilCareClinicalAPI/Services/Simulation/SessionCatalog.cs

@@ -0,0 +1,139 @@
+using System.Text.Json;
+using Microsoft.Extensions.Options;
+
+public interface ISessionCatalog
+{
+    IReadOnlyList<SessionPreset> ListSessions();
+    SessionPreset? GetById(string sessionId);
+}
+
+public sealed record SessionPreset(
+    string Id,
+    string Name,
+    string Goal,
+    int EstimatedMinutes,
+    double DefaultSpeed,
+    IReadOnlyList<string> Scenarios);
+
+/// <summary>
+/// Loads <c>sessions.json</c> from the scenario directory (or its parent) and
+/// validates every referenced scenario id against <see cref="IScenarioCatalog"/>
+/// at construction — a typo fails loudly at startup.
+/// </summary>
+public sealed class SessionCatalog : ISessionCatalog
+{
+    private static readonly JsonSerializerOptions JsonOptions = new()
+    {
+        PropertyNameCaseInsensitive = true,
+    };
+
+    private readonly IReadOnlyList<SessionPreset> _sessions;
+
+    public SessionCatalog(IOptions<SimulationOptions> options, IScenarioCatalog scenarios)
+    {
+        var directory = options.Value.ScenarioDirectory;
+        var path = ResolveManifestPath(directory)
+            ?? throw new InvalidOperationException(
+                $"Simulation session manifest not found. Expected sessions.json in or beside " +
+                $"ScenarioDirectory '{Path.GetFullPath(directory)}'.");
+
+        _sessions = LoadAndValidate(path, scenarios);
+    }
+
+    public IReadOnlyList<SessionPreset> ListSessions() => _sessions;
+
+    public SessionPreset? GetById(string sessionId) =>
+        _sessions.FirstOrDefault(s =>
+            string.Equals(s.Id, sessionId, StringComparison.OrdinalIgnoreCase));
+
+    internal static string? ResolveManifestPath(string scenarioDirectory)
+    {
+        var inDir = Path.Combine(scenarioDirectory, "sessions.json");
+        if (File.Exists(inDir))
+            return inDir;
+
+        var parent = Directory.GetParent(Path.GetFullPath(scenarioDirectory))?.FullName;
+        if (parent is not null)
+        {
+            var beside = Path.Combine(parent, "sessions.json");
+            if (File.Exists(beside))
+                return beside;
+        }
+
+        return null;
+    }
+
+    internal static IReadOnlyList<SessionPreset> LoadAndValidate(
+        string path, IScenarioCatalog scenarios)
+    {
+        SessionsDocument doc;
+        try
+        {
+            var json = File.ReadAllText(path);
+            doc = JsonSerializer.Deserialize<SessionsDocument>(json, JsonOptions)
+                ?? throw new InvalidOperationException(
+                    $"Session manifest '{path}' deserialized to null.");
+        }
+        catch (Exception ex) when (ex is not InvalidOperationException)
+        {
+            throw new InvalidOperationException(
+                $"Failed to load simulation session manifest '{path}': {ex.Message}", ex);
+        }
+
+        if (doc.Sessions is null || doc.Sessions.Count == 0)
+            throw new InvalidOperationException(
+                $"Session manifest '{path}' contains no sessions.");
+
+        var presets = new List<SessionPreset>(doc.Sessions.Count);
+        var missing = new List<string>();
+
+        foreach (var entry in doc.Sessions)
+        {
+            if (string.IsNullOrWhiteSpace(entry.Id))
+                throw new InvalidOperationException(
+                    $"Session manifest '{path}' has a session with an empty id.");
+
+            if (entry.Scenarios is null || entry.Scenarios.Count == 0)
+                throw new InvalidOperationException(
+                    $"Session '{entry.Id}' in '{path}' lists no scenarios.");
+
+            foreach (var scenarioId in entry.Scenarios)
+            {
+                if (scenarios.GetById(scenarioId) is null)
+                    missing.Add($"{entry.Id} → {scenarioId}");
+            }
+
+            presets.Add(new SessionPreset(
+                entry.Id,
+                entry.Name ?? entry.Id,
+                entry.Goal ?? string.Empty,
+                entry.EstimatedMinutes,
+                entry.DefaultSpeed <= 0 ? 60 : entry.DefaultSpeed,
+                entry.Scenarios.AsReadOnly()));
+        }
+
+        if (missing.Count > 0)
+        {
+            throw new InvalidOperationException(
+                "Session manifest references unknown scenario id(s): " +
+                string.Join("; ", missing));
+        }
+
+        return presets;
+    }
+
+    private sealed class SessionsDocument
+    {
+        public List<SessionEntry>? Sessions { get; set; }
+    }
+
+    private sealed class SessionEntry
+    {
+        public string Id { get; set; } = null!;
+        public string? Name { get; set; }
+        public string? Goal { get; set; }
+        public int EstimatedMinutes { get; set; }
+        public double DefaultSpeed { get; set; }
+        public List<string>? Scenarios { get; set; }
+    }
+}