autosave proj every 2min if sequencer not running

also improve code docs for mainloop, events and clock tick event

docs/DEV.md

@@ -95,4 +95,17 @@ A helpful tool for debugging MIDI output is [ShowMIDI](https://github.com/gbevin
 
 ### USB MIDI output
 
-TODO
+TODO
+
+## Notes on code structure
+
+### Key classes
+
+Some classes are worth documenting specifically here as they contain key pieces of functionality.
+
+`sources/Adapters/picoTracker/gui/picoTrackerEventManager.cpp`
+
+`picoTrackerEventManager` is important because it's where `MainLoop()` is and hence it's where "events" are dispatched. 
+It is also here that the 1ms tick timer callback is set up and the callback function for it is found: `timerHandler()`. The `timerHandler()` function is then the source of the `PICO_CLOCK` events, which are then dispatched to the `picoTrackerEventQueue` at the rate of 1Hz.
+
+`AppWindow::AnimationUpdate()` is the handy spot where we handle calling autosave just because of the convienence of the `AppWindow` class having easy access to the player, the current project name and the persistance service.

sources/Adapters/picoTracker/gui/picoTrackerEventManager.cpp

@@ -31,9 +31,12 @@ picoTrackerEventQueue *queue;
 char inBuffer[INPUT_BUFFER_SIZE];
 #endif
 
+// timer callback at a rate of 1kHz (from a 1ms hardware interrupt timer)
 bool timerHandler(repeating_timer_t *rt) {
   queue = picoTrackerEventQueue::GetInstance();
   gTime_++;
+
+  // send a clock (PICO_CLOCK) event once every second
   if (gTime_ % 1000 == 0) {
     queue->push(picoTrackerEvent(PICO_CLOCK));
   }
@@ -58,9 +61,7 @@ bool picoTrackerEventManager::Init() {
 
   keyboardCS_ = new KeyboardControllerSource("keyboard");
 
-  // TODO: fix this, there is a timer service that should be used. Also all of
-  // this keyRepeat logic is already implemented in the eventdispatcher
-  // Application/Commands/EventDispatcher.cpp
+  // setup a repeating timer for 1ms ticks
   add_repeating_timer_ms(1, timerHandler, NULL, &timer_);
   return true;
 }

sources/Adapters/picoTracker/gui/picoTrackerGUIWindowImp.cpp

@@ -2,6 +2,7 @@
 #include "Adapters/picoTracker/utils/utils.h"
 #include "Application/Model/Config.h"
 #include "Application/Utils/char.h"
+#include "Player/Player.h"
 #include "System/Console/Trace.h"
 #include "System/System/System.h"
 #include "UIFramework/BasicDatas/GUIEvent.h"

sources/Application/AppWindow.cpp

@@ -16,6 +16,8 @@
 #include <nanoprintf.h>
 #include <string.h>
 
+const u_int16_t AUTOSAVE_INTERVAL_IN_SECONDS = 2 * 60;
+
 AppWindow *instance = 0;
 
 unsigned char AppWindow::_charScreen[SCREEN_CHARS];
@@ -495,6 +497,18 @@ void AppWindow::AnimationUpdate() {
     loadProject_ = false;
   }
   _currentView->AnimationUpdate();
+
+  // *attempt* to auto save every AUTOSAVE_INTERVAL_IN_MILLIS
+  // will return false if auto save was unsuccessful because eg. the sequencer
+  // is running
+  // we do this here because for sheer convenience because this
+  // callback is called every second and we have easy access in this class to
+  // the player, projectname and persistence service
+  if (++lastAutoSave > AUTOSAVE_INTERVAL_IN_SECONDS) {
+    if (autoSave()) {
+      lastAutoSave = 0;
+    }
+  }
 }
 
 void AppWindow::LayoutChildren(){};
@@ -616,3 +630,16 @@ void AppWindow::Print(char *line) {
 };
 
 void AppWindow::SetColor(ColorDefinition cd) { colorIndex_ = cd; };
+
+bool AppWindow::autoSave() {
+  Player *player = Player::GetInstance();
+  // only auto save when sequencer is not running
+  if (!player->IsRunning()) {
+    Trace::Log("APPWINDOW", "AutoSaving Project Data");
+    // get persistence service and call autosave
+    PersistencyService *ps = PersistencyService::GetInstance();
+    ps->AutoSaveProjectData(projectName_);
+    return true;
+  }
+  return false;
+}

sources/Application/AppWindow.h

@@ -75,6 +75,8 @@ class AppWindow : public GUIWindow, I_Observer, Status {
   void onQuitApp();
 
 private:
+  bool autoSave();
+
   View *_currentView;
   ViewData *_viewData;
   SongView *_songView;
@@ -120,6 +122,8 @@ class AppWindow : public GUIWindow, I_Observer, Status {
   SysMutex drawMutex_;
 
   bool loadProject_ = false;
+
+  uint32_t lastAutoSave = 0;
 };
 
 #endif

sources/Application/Persistency/PersistencyService.cpp

@@ -133,11 +133,15 @@ PersistencyResult PersistencyService::SaveProjectData(const char *projectName,
   fp->Close();
   delete (fp);
 
-  // if *not* doing auto save, then we need to delete the existing autosave
+  // if we are doing an explicit save (ie nto a autosave), then we need to
+  // delete the existing autosave file so that this explicit save will be loaded
+  // in case subsequent autosave has changes the user doesn't want to keep
   if (!autosave) {
     etl::vector segments = {PROJECTS_DIR, projectName, AUTO_SAVE_FILENAME};
     CreatePath(pathBufferA, segments);
     picoFS->DeleteFile(pathBufferA.c_str());
+    Trace::Log("PERSISTENCYSERVICE", "Deleted Autosave File: %s\n",
+               pathBufferA.c_str());
   }
 
   return PERSIST_SAVED;
@@ -228,7 +232,9 @@ void PersistencyService::CreatePath(
   path.clear();
   // iterate over segments and concatenate using iterator
   for (auto it = segments.begin(); it != segments.end(); ++it) {
-    path.append("/");
     path.append(*it);
+    if (it != segments.end() - 1) {
+      path.append("/");
+    }
   }
 }