From 06113b4ffe3b76d85f2744751cfac646b90e9cca Mon Sep 17 00:00:00 2001
From: Andreas Kling <awesomekling@gmail.com>
Date: Thu, 10 Oct 2019 22:07:08 +0200
Subject: [PATCH] LibHTML+Browser: Show the number of pending resource loads

For now this is simply a counter+hook exposed by ResourceLoader and
shown in the Browser status bar.

This is not very nuanced, and it would be nice to expose more info so
we could eventually do something like a progress bar.
---
 Applications/Browser/main.cpp        | 9 +++++++++
 Libraries/LibHTML/ResourceLoader.cpp | 8 +++++++-
 Libraries/LibHTML/ResourceLoader.h   | 6 ++++++
 3 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/Applications/Browser/main.cpp b/Applications/Browser/main.cpp
index ff6387d9ac..d2bb486145 100644
--- a/Applications/Browser/main.cpp
+++ b/Applications/Browser/main.cpp
@@ -18,6 +18,7 @@
 #include <LibHTML/Layout/LayoutNode.h>
 #include <LibHTML/Parser/CSSParser.h>
 #include <LibHTML/Parser/HTMLParser.h>
+#include <LibHTML/ResourceLoader.h>
 #include <stdio.h>
 
 static const char* home_url = "file:///home/anon/www/welcome.html";
@@ -78,6 +79,14 @@ int main(int argc, char** argv)
 
     auto statusbar = GStatusBar::construct(widget);
 
+    ResourceLoader::the().on_load_counter_change = [&] {
+        if (ResourceLoader::the().pending_loads() == 0) {
+            statusbar->set_text("");
+            return;
+        }
+        statusbar->set_text(String::format("Loading (%d pending resources...)", ResourceLoader::the().pending_loads()));
+    };
+
     auto menubar = make<GMenuBar>();
 
     auto app_menu = make<GMenu>("Browser");
diff --git a/Libraries/LibHTML/ResourceLoader.cpp b/Libraries/LibHTML/ResourceLoader.cpp
index 95c8c2106a..c0c3fe9916 100644
--- a/Libraries/LibHTML/ResourceLoader.cpp
+++ b/Libraries/LibHTML/ResourceLoader.cpp
@@ -35,7 +35,13 @@ void ResourceLoader::load(const URL& url, Function<void(const ByteBuffer&)> call
         request.set_url(url);
         request.set_method(CHttpRequest::Method::GET);
         auto job = request.schedule();
-        job->on_finish = [job, callback = move(callback)](bool success) {
+        ++m_pending_loads;
+        if (on_load_counter_change)
+            on_load_counter_change();
+        job->on_finish = [this, job, callback = move(callback)](bool success) {
+            --m_pending_loads;
+            if (on_load_counter_change)
+                on_load_counter_change();
             if (!success) {
                 dbg() << "HTTP job failed!";
                 ASSERT_NOT_REACHED();
diff --git a/Libraries/LibHTML/ResourceLoader.h b/Libraries/LibHTML/ResourceLoader.h
index 8255e5a8cd..7d5826efc9 100644
--- a/Libraries/LibHTML/ResourceLoader.h
+++ b/Libraries/LibHTML/ResourceLoader.h
@@ -11,6 +11,12 @@ public:
 
     void load(const URL&, Function<void(const ByteBuffer&)>);
 
+    Function<void()> on_load_counter_change;
+
+    int pending_loads() const { return m_pending_loads; }
+
 private:
     ResourceLoader() {}
+
+    int m_pending_loads { 0 };
 };