From bf1d17ad7dd4707e6f41e83a145c145bab727cf5 Mon Sep 17 00:00:00 2001
From: Federico Terzi <federicoterzi96@gmail.com>
Date: Sat, 14 Aug 2021 11:43:23 +0200
Subject: [PATCH] feat(core): cache app info provider results

---
 .../worker/engine/caches/app_info_provider.rs | 56 +++++++++++++++++++
 espanso/src/cli/worker/engine/caches/mod.rs   | 20 +++++++
 espanso/src/cli/worker/engine/mod.rs          |  7 ++-
 3 files changed, 81 insertions(+), 2 deletions(-)
 create mode 100644 espanso/src/cli/worker/engine/caches/app_info_provider.rs
 create mode 100644 espanso/src/cli/worker/engine/caches/mod.rs

diff --git a/espanso/src/cli/worker/engine/caches/app_info_provider.rs b/espanso/src/cli/worker/engine/caches/app_info_provider.rs
new file mode 100644
index 0000000..6b03863
--- /dev/null
+++ b/espanso/src/cli/worker/engine/caches/app_info_provider.rs
@@ -0,0 +1,56 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+use std::{cell::RefCell, time::{Duration, Instant}};
+
+use espanso_info::{AppInfo, AppInfoProvider};
+
+pub struct CachedAppInfoProvider<'a> {
+  app_info_provider: &'a dyn AppInfoProvider,
+  caching_interval: Duration,
+  
+  _cached_info: RefCell<Option<(Instant, AppInfo)>>,
+}
+
+impl<'a> CachedAppInfoProvider<'a> {
+  pub fn from(app_info_provider: &'a dyn AppInfoProvider, caching_interval: Duration) -> Self {
+    Self {
+      app_info_provider,
+      caching_interval,
+      _cached_info: RefCell::new(None),
+    }
+  }
+}
+
+impl<'a> AppInfoProvider for CachedAppInfoProvider<'a> {
+  fn get_info(&self) -> espanso_info::AppInfo {
+    let mut cached_info = self._cached_info.borrow_mut();
+    if let Some((instant, cached_value)) = &*cached_info {
+      if instant.elapsed() < self.caching_interval {
+        // Return cached config
+        return cached_value.clone();
+      }
+    }
+
+    let info = self.app_info_provider.get_info();
+    *cached_info = Some((Instant::now(), info.clone()));
+    
+    info
+  }
+}
diff --git a/espanso/src/cli/worker/engine/caches/mod.rs b/espanso/src/cli/worker/engine/caches/mod.rs
new file mode 100644
index 0000000..d5f2e9d
--- /dev/null
+++ b/espanso/src/cli/worker/engine/caches/mod.rs
@@ -0,0 +1,20 @@
+/*
+ * This file is part of espanso.
+ *
+ * Copyright (C) 2019-2021 Federico Terzi
+ *
+ * espanso is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * espanso is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with espanso.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+pub mod app_info_provider;
\ No newline at end of file
diff --git a/espanso/src/cli/worker/engine/mod.rs b/espanso/src/cli/worker/engine/mod.rs
index 105ea91..669f94c 100644
--- a/espanso/src/cli/worker/engine/mod.rs
+++ b/espanso/src/cli/worker/engine/mod.rs
@@ -49,6 +49,7 @@ use super::secure_input::SecureInputEvent;
 pub mod dispatch;
 pub mod funnel;
 pub mod process;
+mod caches;
 mod keyboard_layout_util;
 
 #[allow(clippy::too_many_arguments)]
@@ -71,15 +72,17 @@ pub fn initialize_and_spawn(
 
       let app_info_provider =
         espanso_info::get_provider().expect("unable to initialize app info provider");
+      // TODO: read interval from configs?
+      let cached_app_info_provider = caches::app_info_provider::CachedAppInfoProvider::from(&*app_info_provider, std::time::Duration::from_millis(400));
       let config_manager =
-        super::config::ConfigManager::new(&*config_store, &*match_store, &*app_info_provider);
+        super::config::ConfigManager::new(&*config_store, &*match_store, &cached_app_info_provider);
       let match_cache = MatchCache::load(&*config_store, &*match_store);
 
       let modulo_manager = crate::gui::modulo::manager::ModuloManager::new();
       let modulo_form_ui = crate::gui::modulo::form::ModuloFormUI::new(&modulo_manager);
       let modulo_search_ui = crate::gui::modulo::search::ModuloSearchUI::new(&modulo_manager);
 
-      let context: Box<dyn Context> = Box::new(super::context::DefaultContext::new(&config_manager, &*app_info_provider));
+      let context: Box<dyn Context> = Box::new(super::context::DefaultContext::new(&config_manager, &cached_app_info_provider));
       let builtin_matches = super::builtin::get_builtin_matches(&*config_manager.default());
       let combined_match_cache = CombinedMatchCache::load(&match_cache, &builtin_matches);