feat(premium): let self-hosted instances sell premium and gifts (#3025)

fluxer_admin/src/state.rs

@@ -1,7 +1,18 @@
 // SPDX-License-Identifier: AGPL-3.0-or-later
 
-use crate::config::AdminConfig;
-use std::sync::Arc;
+use crate::{
+    api::{
+        client::{AdminApiClient, ApiResultExt},
+        types::PremiumBranding,
+    },
+    config::AdminConfig,
+};
+use std::{
+    sync::{Arc, Mutex},
+    time::{Duration, Instant},
+};
+
+const PREMIUM_BRANDING_TTL: Duration = Duration::from_secs(60);
 
 #[derive(Clone)]
 pub struct AppState {
@@ -11,6 +22,7 @@ pub struct AppState {
 struct AppStateInner {
     pub config: AdminConfig,
     pub http_client: reqwest::Client,
+    premium_branding: Mutex<Option<(Instant, PremiumBranding)>>,
 }
 
 impl AppState {
@@ -23,6 +35,7 @@ impl AppState {
             inner: Arc::new(AppStateInner {
                 config,
                 http_client,
+                premium_branding: Mutex::new(None),
             }),
         }
     }
@@ -34,6 +47,40 @@ impl AppState {
     pub fn http_client(&self) -> &reqwest::Client {
         &self.inner.http_client
     }
+
+    pub fn cached_premium_branding(&self) -> Option<PremiumBranding> {
+        let cache = self
+            .inner
+            .premium_branding
+            .lock()
+            .unwrap_or_else(|poisoned| poisoned.into_inner());
+        cache
+            .as_ref()
+            .filter(|(fetched_at, _)| fetched_at.elapsed() < PREMIUM_BRANDING_TTL)
+            .map(|(_, branding)| branding.clone())
+    }
+
+    pub fn remember_premium_branding(&self, branding: PremiumBranding) {
+        *self
+            .inner
+            .premium_branding
+            .lock()
+            .unwrap_or_else(|poisoned| poisoned.into_inner()) = Some((Instant::now(), branding));
+    }
+
+    pub async fn premium_branding(&self, client: &AdminApiClient) -> Option<PremiumBranding> {
+        if let Some(branding) = self.cached_premium_branding() {
+            return Some(branding);
+        }
+        let branding = PremiumBranding::from_discovery(
+            &client
+                .get_instance_premium_discovery()
+                .await
+                .log_error("load premium branding")?,
+        );
+        self.remember_premium_branding(branding.clone());
+        Some(branding)
+    }
 }
 
 impl axum::extract::FromRef<AppState> for AdminConfig {