From 579bee3b75afbcf1d70a13633aaf00e74a592880 Mon Sep 17 00:00:00 2001
From: Matthias Koefferlein <matthias@klayout.de>
Date: Tue, 31 Oct 2023 22:30:52 +0100
Subject: [PATCH] Implemented package information cache in package manager

---
 src/lay/lay/laySaltManagerDialog.cc | 51 ++++++++++++++++++++---------
 src/lay/lay/laySaltManagerDialog.h  |  1 +
 2 files changed, 37 insertions(+), 15 deletions(-)

diff --git a/src/lay/lay/laySaltManagerDialog.cc b/src/lay/lay/laySaltManagerDialog.cc
index b034f93e8..d78aa5ebe 100644
--- a/src/lay/lay/laySaltManagerDialog.cc
+++ b/src/lay/lay/laySaltManagerDialog.cc
@@ -857,6 +857,8 @@ SaltManagerDialog::salt_mine_about_to_change ()
 void
 SaltManagerDialog::refresh ()
 {
+  m_salt_grain_cache.clear ();
+
   if (! m_salt_mine_url.empty ()) {
 
     tl::log << tl::to_string (tr ("Downloading package repository from %1").arg (tl::to_qstring (m_salt_mine_url)));
@@ -1227,10 +1229,12 @@ SaltManagerDialog::get_remote_grain_info (lay::SaltGrain *g, SaltGrainDetailsTex
   tl_assert (m_downloaded_grain.get () == 0);
 
   m_downloaded_grain.reset (0);
+
   if (m_downloaded_grain_reader.get ()) {
-    //  NOTE: don't delete the reader in the slot it triggered
     m_downloaded_grain_reader->close ();
   }
+  m_downloaded_grain_reader.reset (0);
+
   mp_downloaded_target = details;
   m_salt_mine_grain.reset (new lay::SaltGrain (*g));
 
@@ -1262,21 +1266,31 @@ SaltManagerDialog::get_remote_grain_info (lay::SaltGrain *g, SaltGrainDetailsTex
 
       std::string url = g->url ();
 
-      m_downloaded_grain.reset (new SaltGrain ());
-      m_downloaded_grain->set_url (url);
+      auto sg = m_salt_grain_cache.find (url);
+      if (sg == m_salt_grain_cache.end ()) {
 
-      //  NOTE: stream_from_url may modify the URL, hence we set it again
-      ProcessEventCallback callback;
-      m_downloaded_grain_reader.reset (SaltGrain::stream_from_url (url, 60.0, &callback));
-      m_downloaded_grain->set_url (url);
+        m_downloaded_grain.reset (new SaltGrain ());
+        m_downloaded_grain->set_url (url);
+
+        //  NOTE: stream_from_url may modify the URL, hence we set it again
+        ProcessEventCallback callback;
+        m_downloaded_grain_reader.reset (SaltGrain::stream_from_url (url, 60.0, &callback));
+        m_downloaded_grain->set_url (url);
+
+        tl::InputHttpStream *http = dynamic_cast<tl::InputHttpStream *> (m_downloaded_grain_reader->base ());
+        if (http) {
+          //  async reading on HTTP
+          http->ready ().add (this, &SaltManagerDialog::data_ready);
+          http->send ();
+        } else {
+          data_ready ();
+        }
 
-      tl::InputHttpStream *http = dynamic_cast<tl::InputHttpStream *> (m_downloaded_grain_reader->base ());
-      if (http) {
-        //  async reading on HTTP
-        http->ready ().add (this, &SaltManagerDialog::data_ready);
-        http->send ();
       } else {
+
+        m_downloaded_grain.reset (new SaltGrain (sg->second));
         data_ready ();
+
       }
 
     } catch (tl::Exception &ex) {
@@ -1295,14 +1309,21 @@ SaltManagerDialog::get_remote_grain_info (lay::SaltGrain *g, SaltGrainDetailsTex
 void
 SaltManagerDialog::data_ready ()
 {
-  if (! m_salt_mine_grain.get () || ! m_downloaded_grain.get () || ! m_downloaded_grain_reader.get () || ! mp_downloaded_target) {
+  if (! m_salt_mine_grain.get () || ! m_downloaded_grain.get () || ! mp_downloaded_target) {
     return;
   }
 
   //  Load the grain file (save URL as it is overwritten by the grain.xml content)
   std::string url = m_downloaded_grain->url ();
-  m_downloaded_grain->load (*m_downloaded_grain_reader);
-  m_downloaded_grain->set_url (url);
+  if (m_downloaded_grain_reader.get ()) {
+    m_downloaded_grain->load (*m_downloaded_grain_reader);
+    m_downloaded_grain->set_url (url);
+  }
+
+  //  commit to cache
+  if (m_salt_grain_cache.find (url) == m_salt_grain_cache.end ()) {
+    m_salt_grain_cache [url] = *m_downloaded_grain;
+  }
 
   try {
 
diff --git a/src/lay/lay/laySaltManagerDialog.h b/src/lay/lay/laySaltManagerDialog.h
index db3851801..dd899371b 100644
--- a/src/lay/lay/laySaltManagerDialog.h
+++ b/src/lay/lay/laySaltManagerDialog.h
@@ -190,6 +190,7 @@ private:
   std::unique_ptr<tl::InputStream> m_salt_mine_reader;
   tl::DeferredMethod<SaltManagerDialog> dm_mine_update_selected_changed;
   tl::DeferredMethod<SaltManagerDialog> dm_mine_new_selected_changed;
+  std::map<std::string, lay::SaltGrain> m_salt_grain_cache;
 
   SaltGrain *current_grain ();
   std::vector<lay::SaltGrain *> current_grains ();