From ff5af54b07195046382f8d0c158d41fa96bf7eec Mon Sep 17 00:00:00 2001
From: HJfod <60038575+HJfod@users.noreply.github.com>
Date: Sun, 10 Mar 2024 13:26:47 +0200
Subject: [PATCH] cache server icon results

---
 loader/src/server/Server.hpp | 136 +++++++++++++++++++++++++++++++++++
 loader/src/ui/GeodeUI.cpp    |   4 +-
 2 files changed, 139 insertions(+), 1 deletion(-)

diff --git a/loader/src/server/Server.hpp b/loader/src/server/Server.hpp
index a2727a2a..907c029f 100644
--- a/loader/src/server/Server.hpp
+++ b/loader/src/server/Server.hpp
@@ -97,4 +97,140 @@ namespace server {
     ServerPromise<ServerModsList> getMods(ModsQuery const& query);
     ServerPromise<ServerModMetadata> getMod(std::string const& id);
     ServerPromise<ByteVector> getModLogo(std::string const& id);
+
+    // Caching for server endpoints
+    namespace impl_cache {
+        template <class R, class Q>
+        struct ExtractServerReqParams {
+            using Result = R;
+            using Query  = Q;
+            ExtractServerReqParams(ServerPromise<R>(*)(Q const&)) {}
+        };
+
+        template <auto F>
+        class ServerResultCache final {
+        public:
+            using Extract = decltype(ExtractServerReqParams(F));
+            using Result  = Extract::Result;
+            using Query   = Extract::Query;
+
+        private:
+            std::mutex m_cachedMutex;
+            // The result and the query used for cached value
+            std::optional<std::pair<Result, Query>> m_cached;
+
+            ServerPromise<Result> fetch(Query&& query) {
+                return ServerPromise<Result>([this, query = std::move(query)](auto resolve, auto reject, auto progress, auto cancelled) {
+                    F(Query(query))
+                    .then([this, resolve, query = std::move(query)](auto res) {
+                        std::unique_lock lock(m_cachedMutex);
+                        m_cached = { res, query };
+                        lock.unlock();
+
+                        resolve(res);
+                    })
+                    .expect([reject](auto err) {
+                        reject(err);
+                    })
+                    .progress([progress](auto prog) {
+                        progress(prog);
+                    })
+                    .link(cancelled);
+                });
+            }
+        
+        public:
+            ServerPromise<Result> get(Query&& query) {
+                std::unique_lock lock(m_cachedMutex);
+                // Return cached value if there is one and the query matches
+                if (m_cached && m_cached->second == query) {
+                    auto cached = m_cached->first;
+                    lock.unlock();
+                    return ServerPromise<Result>([cached = std::move(cached)](auto resolve, auto) {
+                        resolve(std::move(cached));
+                    });
+                }
+                lock.unlock();
+                return this->fetch(std::move(query));
+            }
+
+            ServerPromise<Result> refetch(Query&& query) {
+                // Clear cache
+                std::unique_lock lock(m_cachedMutex);
+                m_cached.reset();
+                lock.unlock();
+
+                // Fetch new value
+                return this->fetch(std::move(query));
+            }
+        };
+
+        template <auto F>
+        class ServerMultiResultCache final {
+        public:
+            using Extract = decltype(ExtractServerReqParams(F));
+            using Result  = Extract::Result;
+            using Query   = Extract::Query;
+
+        private:
+            std::mutex m_queriesMutex;
+            std::map<Query, Result> m_queries;
+        
+            ServerPromise<Result> fetch(Query const& query) {
+                return ServerPromise<Result>([this, query = Query(query)](auto resolve, auto reject, auto progress, auto cancelled) {
+                    F(Query(query))
+                    .then([this, resolve, query = std::move(query)](auto res) {
+                        std::unique_lock lock(m_queriesMutex);
+                        m_queries[std::move(query)] = res;
+                        lock.unlock();
+
+                        resolve(res);
+                    })
+                    .expect([reject](auto err) {
+                        reject(err);
+                    })
+                    .progress([progress](auto prog) {
+                        progress(prog);
+                    })
+                    .link(cancelled);
+                });
+            }
+
+        public:
+            ServerPromise<Result> get(Query const& query) {
+                std::unique_lock lock(m_queriesMutex);
+                // Return cached value if there is one and the query matches
+                if (m_queries.contains(query)) {
+                    auto cached = m_queries.at(query);
+                    lock.unlock();
+                    return ServerPromise<Result>([cached = std::move(cached)](auto resolve, auto) {
+                        resolve(std::move(cached));
+                    });
+                }
+                lock.unlock();
+                return this->fetch(std::move(query));
+            }
+
+            ServerPromise<Result> refetch(Query const& query) {
+                // Clear cache for this query only
+                std::unique_lock lock (m_queriesMutex);
+                m_queries.erase(query);
+                lock.unlock();
+
+                // Fetch new value
+                return this->fetch(std::move(query));
+            }
+
+            // Clear all caches
+            void invalidateAll() {
+                std::unique_lock _(m_queriesMutex);
+                m_queries.clear();
+            }
+        };
+    }
+
+    // todo: default shared caching for endpoints for all users
+    // todo: (so it can be automatically cleared for example after leaving the geode layer)
+    // template <auto F>
+    // impl_cache::ServerResultCache<F> sharedCache() {}
 }
diff --git a/loader/src/ui/GeodeUI.cpp b/loader/src/ui/GeodeUI.cpp
index 49ad84ca..274259a7 100644
--- a/loader/src/ui/GeodeUI.cpp
+++ b/loader/src/ui/GeodeUI.cpp
@@ -70,6 +70,8 @@ protected:
     std::string m_modID;
     CCNode* m_sprite = nullptr;
     EventListener<PromiseEventFilter<ByteVector, server::ServerError>> m_listener;
+    // todo: use shared cache once impl'd
+    static inline server::impl_cache::ServerMultiResultCache<&server::getModLogo> s_cache = {};
 
     bool init(std::string const& id, bool fetch) {
         if (!CCNode::init())
@@ -93,7 +95,7 @@ protected:
             this->setSprite(CCSprite::create("loadingCircle.png"));
             static_cast<CCSprite*>(m_sprite)->setBlendFunc({ GL_ONE, GL_ONE });
             m_sprite->runAction(CCRepeatForever::create(CCRotateBy::create(1.f, 360.f)));
-            m_listener.setFilter(server::getModLogo(id).listen());
+            m_listener.setFilter(s_cache.get(id).listen());
         }
 
         return true;