feat: Implement oauth service and client registration

src/api/client/oauth/server_metadata.rs

@@ -0,0 +1,34 @@
+use axum::extract::State;
+use conduwuit::Result;
+use ruma::{api::client::discovery::get_authorization_server_metadata, serde::Raw};
+use serde_json::json;
+
+use crate::Ruma;
+
+pub(crate) async fn get_authorization_server_metadata_route(
+	State(services): State<crate::State>,
+	_body: Ruma<get_authorization_server_metadata::v1::Request>,
+) -> Result<get_authorization_server_metadata::v1::Response> {
+	let endpoint_base = services
+		.config
+		.get_client_domain()
+		.join(super::BASE_PATH)
+		.unwrap();
+
+	let metadata = Raw::new(&json!({
+		"authorization_endpoint": endpoint_base.join("grant/authorization_code").unwrap(),
+		"code_challenge_methods_supported": ["S256"],
+		"grant_types_supported": ["authorization_code", "refresh_token"],
+		"issuer": services.config.get_client_domain(),
+		"jwks_uri": endpoint_base.join("client/keys.json").unwrap(),
+		"prompt_values_supported": ["create"],
+		"registration_endpoint": endpoint_base.join("client/register").unwrap(),
+		"response_modes_supported": ["query", "fragment"],
+		"response_types_supported": ["code"],
+		"revocation_endpoint": endpoint_base.join("client/revoke").unwrap(),
+		"token_endpoint": endpoint_base.join("grant/token").unwrap(),
+	}))
+	.unwrap();
+
+	Ok(get_authorization_server_metadata::v1::Response::new(metadata.cast_unchecked()))
+}