cc nasazeni

Credentials/RequestCredentialsProvider.cs

@@ -0,0 +1,73 @@
+using IdokladSdk.Enums;
+using Idoklad.Configuration;
+
+namespace Idoklad.Credentials;
+
+/// <summary>
+/// Resolves the iDoklad credentials for the current request.
+///
+/// Mirrors <c>get_request_settings</c> from the sibling microsoft-365-service: each credential
+/// value is taken from its request header when present and otherwise falls back to the
+/// environment-configured default. Secrets are only ever read from headers (never query/body).
+/// If, after applying the fallbacks, any required value is still missing, the request is rejected.
+/// </summary>
+public sealed class RequestCredentialsProvider
+{
+    private readonly IHttpContextAccessor _httpContextAccessor;
+    private readonly IdokladSettings _settings;
+
+    public RequestCredentialsProvider(IHttpContextAccessor httpContextAccessor, IdokladSettings settings)
+    {
+        _httpContextAccessor = httpContextAccessor;
+        _settings = settings;
+    }
+
+    public IdokladCredentials Resolve()
+    {
+        var headers = _httpContextAccessor.HttpContext?.Request.Headers;
+
+        var clientId = HeaderOrDefault(headers, CredentialConstants.ClientIdHeader, _settings.ClientId);
+        var clientSecret = HeaderOrDefault(headers, CredentialConstants.ClientSecretHeader, _settings.ClientSecret);
+        var applicationId = HeaderOrDefault(headers, CredentialConstants.ApplicationIdHeader, _settings.ApplicationId);
+
+        var missing = new List<string>();
+        if (string.IsNullOrWhiteSpace(clientId)) missing.Add(CredentialConstants.ClientIdHeader);
+        if (string.IsNullOrWhiteSpace(clientSecret)) missing.Add(CredentialConstants.ClientSecretHeader);
+        if (string.IsNullOrWhiteSpace(applicationId)) missing.Add(CredentialConstants.ApplicationIdHeader);
+        if (missing.Count > 0)
+        {
+            throw new MissingCredentialsException(missing);
+        }
+
+        return new IdokladCredentials
+        {
+            ClientId = clientId!,
+            ClientSecret = clientSecret!,
+            ApplicationId = applicationId!,
+            Language = ResolveLanguage(headers),
+        };
+    }
+
+    private Language ResolveLanguage(IHeaderDictionary? headers)
+    {
+        var raw = headers is not null && headers.TryGetValue(CredentialConstants.LanguageHeader, out var value)
+            ? value.ToString()
+            : null;
+
+        return Enum.TryParse<Language>(raw, ignoreCase: true, out var parsed) ? parsed : _settings.Language;
+    }
+
+    private static string? HeaderOrDefault(IHeaderDictionary? headers, string name, string fallback)
+    {
+        if (headers is not null && headers.TryGetValue(name, out var value))
+        {
+            var headerValue = value.ToString();
+            if (!string.IsNullOrWhiteSpace(headerValue))
+            {
+                return headerValue;
+            }
+        }
+
+        return string.IsNullOrWhiteSpace(fallback) ? null : fallback;
+    }
+}