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 +1,96 @@
+using Hl7.Fhir.Model;
+using Microsoft.Extensions.Options;
+using Task = System.Threading.Tasks.Task;
+
+public class FhirReferenceResolver
+{
+    private readonly IExternalIdentifierService _identifiers;
+    private readonly FhirOptions _options;
+
+    public FhirReferenceResolver(
+        IExternalIdentifierService identifiers,
+        IOptions<FhirOptions> options)
+    {
+        _identifiers = identifiers;
+        _options = options.Value;
+    }
+
+    public async Task<Guid> ResolvePatientReferenceAsync(ResourceReference reference)
+    {
+        if (reference.Identifier is not null)
+            return await ResolveByIdentifierAsync(
+                ExternalResourceType.Patient,
+                reference.Identifier.System,
+                reference.Identifier.Value,
+                _options.PatientIdentifierSystems);
+
+        if (FhirMappingHelpers.TryParseResourceReference(reference.Reference, out var type, out var id)
+            && type == "Patient"
+            && Guid.TryParse(id, out var guid))
+        {
+            return guid;
+        }
+
+        throw new FhirMappingException(
+            "Patient reference must include a resolvable identifier or UUID.",
+            "required");
+    }
+
+    public async Task<Guid> ResolveEncounterReferenceAsync(ResourceReference reference)
+    {
+        if (reference.Identifier is not null)
+            return await ResolveByIdentifierAsync(
+                ExternalResourceType.Encounter,
+                reference.Identifier.System,
+                reference.Identifier.Value,
+                _options.EncounterIdentifierSystems);
+
+        if (FhirMappingHelpers.TryParseResourceReference(reference.Reference, out var type, out var id)
+            && type == "Encounter"
+            && Guid.TryParse(id, out var guid))
+        {
+            return guid;
+        }
+
+        throw new FhirMappingException(
+            "Encounter reference must include a resolvable identifier or UUID.",
+            "required");
+    }
+
+    public (string System, string Value)? ExtractPrimaryIdentifier(
+        IIdentifiable<List<Identifier>> resource, string[] acceptedSystems)
+    {
+        foreach (var system in acceptedSystems)
+        {
+            var match = resource.Identifier?
+                .FirstOrDefault(i => i.System == system && !string.IsNullOrWhiteSpace(i.Value));
+            if (match is not null)
+                return (match.System!, match.Value!);
+        }
+
+        return resource.Identifier?
+            .FirstOrDefault(i => !string.IsNullOrWhiteSpace(i.System) && !string.IsNullOrWhiteSpace(i.Value))
+            is { } fallback
+            ? (fallback.System!, fallback.Value!)
+            : null;
+    }
+
+    private async Task<Guid> ResolveByIdentifierAsync(
+        ExternalResourceType type, string? system, string? value, string[] acceptedSystems)
+    {
+        if (string.IsNullOrWhiteSpace(system) || string.IsNullOrWhiteSpace(value))
+            throw new FhirMappingException("Identifier system and value are required.", "required");
+
+        if (!acceptedSystems.Contains(system))
+            throw new FhirMappingException(
+                $"Identifier system '{system}' is not configured.", "not-supported");
+
+        var internalId = await _identifiers.ResolveInternalIdAsync(type, system, value);
+        if (internalId is null)
+            throw new NotFoundException(
+                $"{type} with identifier {system}|{value} not found.",
+                "FHIR_RESOURCE_NOT_FOUND");
+
+        return internalId.Value;
+    }
+}