Remove power off logo when generation is disabled

Refs: #102

NEWS.md

@@ -12,6 +12,9 @@ adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ### Changed
 
+- Remove power off logo when generation is disabled
+  [#102](https://github.com/orontee/taranis/issues/102)
+
 - Power off logo adapt to screen mode 
   [#101](https://github.com/orontee/taranis/issues/101)
 

src/app.cc

@@ -185,17 +185,18 @@ void App::load_config() {
   // by the backend thus unit system or language change implies that
   // data are obsolete
 
-  const bool generate_shutdown_logo =
-      this->config->read_bool("generate_shutdown_logo", false);
-  if (generate_shutdown_logo) {
-    if (this->ui) {
-      this->ui->generate_logo_maybe();
+  if (this->ui) {
+    this->ui->generate_logo_maybe();
 
-      // A logo generation must be requested after the config changed
-      // since no model update (which triggers a logo generation) may
-      // happen before user open the device configuration panel for
-      // logos (See issue #28)
-    }
+    // A logo generation must be requested after the config changed
+    // since no model update (which triggers a logo generation) may
+    // happen before user open the device configuration panel for
+    // logos (See issue #28)
+
+    // Also don't bother for the value of the configuration key
+    // generate_shutdown_logo since if it changed to false, one must
+    // remove the logo (handled by generate_logo_maybe(), yeah not
+    // that intuitive...)
   }
 
   const auto event_handler = GetEventHandler();

src/logo.cc

@@ -35,16 +35,37 @@ void Logo::do_paint() {
   }
 }
 
+std::string LogoGenerator::get_logo_path() {
+  const auto filename =
+      std::string{USEROFFLOGOPATH} + "/taranis_weather_forecast.bmp";
+
+  return filename;
+}
+
 void LogoGenerator::generate_maybe() const {
   const auto must_generate =
       this->config->read_bool("generate_shutdown_logo", false);
   if (must_generate) {
     this->generate();
   } else {
     BOOST_LOG_TRIVIAL(debug) << "Skipping logo generation";
+    if (LogoGenerator::logo_exists()) {
+      this->remove();
+    }
   }
 }
 
+bool LogoGenerator::logo_exists() {
+  const auto filename = LogoGenerator::get_logo_path();
+  struct stat buffer;
+  if (iv_stat(filename.c_str(), &buffer) == 0) {
+    BOOST_LOG_TRIVIAL(debug) << "Logo exists";
+    return true;
+  }
+  BOOST_LOG_TRIVIAL(debug) << "Logo doesn't exists";
+  return false;
+}
+
 void LogoGenerator::generate() const {
   BOOST_LOG_TRIVIAL(debug) << "Generating new logo";
 
@@ -71,10 +92,16 @@ void LogoGenerator::generate() const {
 
   const auto bitmap =
       BitmapFromCanvas(0, 0, ScreenWidth(), ScreenHeight(), 0, &canvas);
-  const auto filename =
-      std::string{USEROFFLOGOPATH} + "/taranis_weather_forecast.bmp";
+  const auto filename = LogoGenerator::get_logo_path();
   SaveBitmap(filename.data(), bitmap);
 
   SetCanvas(original_canvas);
 }
+
+void LogoGenerator::remove() const {
+  BOOST_LOG_TRIVIAL(debug) << "Removing logo";
+
+  const auto filename = LogoGenerator::get_logo_path();
+  iv_unlink(filename.c_str());
+}
 } // namespace taranis

src/logo.h

@@ -2,6 +2,7 @@
 
 #include <inkview.h>
 #include <memory>
+#include <string>
 
 #include "config.h"
 #include "dailyforecastbox.h"
@@ -37,12 +38,17 @@ struct LogoGenerator {
 
   void generate_maybe() const;
 
+  static std::string get_logo_path();
+
+  static bool logo_exists();
+
 private:
   std::shared_ptr<Config> config;
   std::shared_ptr<Model> model;
   std::shared_ptr<Icons> icons;
   std::shared_ptr<Fonts> fonts;
 
   void generate() const;
+  void remove() const;
 };
 } // namespace taranis