Naming and coding style convention, new linter tool. (#945)

* Makefile, Scripts: new linter
* About: remove ID from IC
* Firmware: remove double define for DIVC/DIVR
* Scripts: check folder names too. Docker: replace syntax check with make lint.
* Reformat Sources and Migrate to new file naming convention
* Docker: symlink clang-format-12 to clang-format
* Add coding style guide

lib/app-template/app_template.h

@@ -0,0 +1,113 @@
+#pragma once
+
+#include "callback-connector.h"
+#include <furi.h>
+#include <furi_hal.h>
+#include <gui/gui.h>
+#include <input/input.h>
+
+// simple app class with template variables <state, events>
+template <class TState, class TEvent> class AppTemplate {
+public:
+    ViewPort* view_port;
+    osMessageQueueId_t event_queue;
+    TState state;
+    ValueMutex state_mutex;
+    Gui* gui;
+
+    AppTemplate();
+    ~AppTemplate();
+    void input_callback(InputEvent* input_event, void* ctx);
+    void draw_callback(Canvas* canvas, void* ctx);
+    virtual void render(Canvas* canvas) = 0;
+    void acquire_state(void);
+    void release_state(void);
+    bool get_event(TEvent* event, uint32_t timeout);
+    void app_ready(void);
+    uint8_t exit(void);
+    void update_gui(void);
+};
+
+template <class TState, class TEvent> AppTemplate<TState, TEvent>::AppTemplate() {
+    // allocate events queue
+    event_queue = osMessageQueueNew(10, sizeof(TEvent), NULL);
+
+    // allocate valuemutex
+    // TODO: use plain os mutex?
+    if(!init_mutex(&state_mutex, &state, sizeof(TState))) {
+        printf("cannot create mutex\n");
+        furi_crash(NULL);
+    }
+
+    // open gui
+    gui = (Gui*)furi_record_open("gui");
+
+    // allocate view_port
+    view_port = view_port_alloc();
+}
+
+template <class TState, class TEvent> AppTemplate<TState, TEvent>::~AppTemplate() {
+}
+
+// generic input callback
+template <class TState, class TEvent>
+void AppTemplate<TState, TEvent>::input_callback(InputEvent* input_event, void* ctx) {
+    AppTemplate* app = static_cast<AppTemplate*>(ctx);
+
+    TEvent event;
+    event.type = TEvent::EventTypeKey;
+    event.value.input = *input_event;
+    osMessageQueuePut(app->event_queue, &event, 0, 0);
+}
+
+// generic draw callback
+template <class TState, class TEvent>
+void AppTemplate<TState, TEvent>::draw_callback(Canvas* canvas, void* ctx) {
+    AppTemplate* app = static_cast<AppTemplate*>(ctx);
+    app->acquire_state();
+
+    canvas_clear(canvas);
+    app->render(canvas);
+
+    app->release_state();
+}
+
+template <class TState, class TEvent> void AppTemplate<TState, TEvent>::acquire_state(void) {
+    acquire_mutex(&state_mutex, osWaitForever);
+}
+
+template <class TState, class TEvent> void AppTemplate<TState, TEvent>::release_state(void) {
+    release_mutex(&state_mutex, &state);
+}
+
+template <class TState, class TEvent>
+bool AppTemplate<TState, TEvent>::get_event(TEvent* event, uint32_t timeout) {
+    osStatus_t event_status = osMessageQueueGet(event_queue, event, NULL, timeout);
+
+    return (event_status == osOK);
+}
+
+// signal that app is ready, and we can render something
+// also unblock dependent tasks
+template <class TState, class TEvent> void AppTemplate<TState, TEvent>::app_ready(void) {
+    // connect view_port with input callback
+    auto input_cb_ref = cbc::obtain_connector(this, &AppTemplate::input_callback);
+    view_port_input_callback_set(view_port, input_cb_ref, this);
+
+    // connect view_port with draw callback
+    auto draw_cb_ref = cbc::obtain_connector(this, &AppTemplate::draw_callback);
+    view_port_draw_callback_set(view_port, draw_cb_ref, this);
+
+    // add view_port
+    gui_add_view_port(gui, view_port, GuiLayerFullscreen);
+}
+
+template <class TState, class TEvent> uint8_t AppTemplate<TState, TEvent>::exit(void) {
+    // TODO remove all view_ports create by app
+    view_port_enabled_set(view_port, false);
+    return 255;
+}
+
+template <class TState, class TEvent> void AppTemplate<TState, TEvent>::update_gui(void) {
+    view_port_update(view_port);
+}