feature: In-App Simulation Runner (Backend)

VigilCare.Simulation.Core/Scenarios/ScenarioLoader.cs

@@ -0,0 +1,59 @@
+using System.Text.Json;
+
+namespace VigilCare.Simulation;
+
+public static class ScenarioLoader
+{
+    private static readonly JsonSerializerOptions JsonOptions = new()
+    {
+        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+        ReadCommentHandling = JsonCommentHandling.Skip,
+        AllowTrailingCommas = true
+    };
+
+    public static ScenarioFile Load(string path)
+    {
+        if (!File.Exists(path))
+            throw new FileNotFoundException($"Scenario file not found: {path}");
+
+        var json = File.ReadAllText(path);
+        var scenario = JsonSerializer.Deserialize<ScenarioFile>(json, JsonOptions)
+            ?? throw new InvalidOperationException($"Failed to deserialize: {path}");
+
+        return scenario with
+        {
+            Events = scenario.Events.OrderBy(e => e.OffsetMinutes).ToList()
+        };
+    }
+
+    /// <summary>
+    /// Enumerates <c>*.json</c> in <paramref name="directory"/>, skips files that
+    /// fail to deserialize, and returns pairs sorted by <see cref="ScenarioMeta.Id"/>.
+    /// </summary>
+    public static IReadOnlyList<(ScenarioFile Scenario, string Path)> LoadAll(string directory)
+    {
+        if (!Directory.Exists(directory))
+            return Array.Empty<(ScenarioFile, string)>();
+
+        var results = new List<(ScenarioFile Scenario, string Path)>();
+
+        foreach (var path in Directory.EnumerateFiles(directory, "*.json")
+                     .Where(p => !string.Equals(
+                         Path.GetFileName(p), "schema.json", StringComparison.OrdinalIgnoreCase))
+                     .OrderBy(p => p, StringComparer.OrdinalIgnoreCase))
+        {
+            try
+            {
+                results.Add((Load(path), path));
+            }
+            catch
+            {
+                // Skip files that fail to deserialize — catalogue must stay resilient.
+            }
+        }
+
+        return results
+            .OrderBy(r => r.Scenario.Scenario.Id, StringComparer.OrdinalIgnoreCase)
+            .ToList();
+    }
+}