feature: FHIR R4 Inbound Facade

2026-06-21 13:53:38 +08:00
parent 9f96f54007
commit a43db52813
42 changed files with 2873 additions and 3 deletions
@@ -0,0 +1,70 @@
+using Microsoft.EntityFrameworkCore;
+
+public class ExternalIdentifierService : IExternalIdentifierService
+{
+    private readonly AppDbContext _db;
+
+    public ExternalIdentifierService(AppDbContext db) => _db = db;
+
+    public async Task<Guid?> ResolveInternalIdAsync(
+        ExternalResourceType resourceType, string system, string value)
+    {
+        var row = await _db.ExternalResourceIdentifiers
+            .AsNoTracking()
+            .FirstOrDefaultAsync(e =>
+                e.ResourceType == resourceType &&
+                e.System == system &&
+                e.Value == value);
+
+        return row?.InternalId;
+    }
+
+    public async Task LinkAsync(
+        ExternalResourceType resourceType, Guid internalId, string system, string value)
+    {
+        var existing = await _db.ExternalResourceIdentifiers
+            .FirstOrDefaultAsync(e =>
+                e.ResourceType == resourceType &&
+                e.System == system &&
+                e.Value == value);
+
+        if (existing is not null)
+        {
+            if (existing.InternalId != internalId)
+                throw new ConflictException(
+                    $"Identifier {system}|{value} is already linked to a different internal resource.",
+                    "IDENTIFIER_ALREADY_LINKED");
+            return;
+        }
+
+        _db.ExternalResourceIdentifiers.Add(new ExternalResourceIdentifier
+        {
+            Id = Guid.NewGuid(),
+            ResourceType = resourceType,
+            InternalId = internalId,
+            System = system,
+            Value = value,
+            CreatedAt = DateTimeOffset.UtcNow
+        });
+
+        await _db.SaveChangesAsync();
+    }
+
+    public async Task<(string System, string Value)?> FindPrimaryIdentifierAsync(
+        ExternalResourceType resourceType, Guid internalId, string[] acceptedSystems)
+    {
+        var rows = await _db.ExternalResourceIdentifiers
+            .AsNoTracking()
+            .Where(e => e.ResourceType == resourceType && e.InternalId == internalId)
+            .ToListAsync();
+
+        foreach (var system in acceptedSystems)
+        {
+            var match = rows.FirstOrDefault(r => r.System == system);
+            if (match is not null)
+                return (match.System, match.Value);
+        }
+
+        return rows.Count > 0 ? (rows[0].System, rows[0].Value) : null;
+    }
+}