caesar_cipher.c

#include <furi.h>
#include <input/input.h>
#include <stdlib.h>

#include <gui/gui.h>
#include <gui/view.h>
#include <gui/view_dispatcher.h>
#include <gui/modules/text_input.h>
#include <gui/modules/text_box.h>

#define TEXT_BUFFER_SIZE 256

typedef enum {
    EventTypeTick,
    EventTypeKey,
} EventType;

typedef struct {
    EventType type;
    InputEvent input;
} PluginEvent;

typedef struct {
  ViewDispatcher* view_dispatcher;
  TextInput* text_input;
  TextBox* text_box;
  char input[TEXT_BUFFER_SIZE];
  char output[(TEXT_BUFFER_SIZE*26) + (26)]; // linebreaks
} CaesarState;

static void string_to_uppercase(char* input) {
  int i;
  for (i=0; input[i] != '\0'; i++) {
    if (input[i] >= 'a' && input[i] <= 'z') {
      input[i] = input[i] - 32;
    } else {
      input[i] = input[i];
    }
  }
}

static void build_output(char* input, char* output) {
  int out = 0;
  for ( int rot = 1; rot < 26; rot++) {
    int in;
    for(in = 0; input[in] != '\0'; in++){
      if (input[in] >= 'A' && input[in] <= 'Z') {
        output[out] = 65 + ( ((input[in] - 65) + rot ) % 26);
      } else {
        output[out] = input[in];
      }
      out++;
    }
    output[out]= '\n';
    out++;
  }
  output[out]='\0';
}

static void text_input_callback(void* ctx) {
  CaesarState* caesar_state = acquire_mutex((ValueMutex*)ctx, 25);
  FURI_LOG_D("caesar_cipher", "Input text: %s", caesar_state->input);
  // this is where we build the output.
  string_to_uppercase(caesar_state->input);
  FURI_LOG_D("caesar_cipher", "Upper text: %s", caesar_state->input);
  build_output(caesar_state->input, caesar_state->output);
  text_box_set_text(caesar_state->text_box, caesar_state->output);
  view_dispatcher_switch_to_view(caesar_state->view_dispatcher, 1);

  release_mutex((ValueMutex*)ctx, caesar_state);
}


static bool back_event_callback(void* ctx) {
  const CaesarState* caesar_state = acquire_mutex((ValueMutex*)ctx, 25);
  view_dispatcher_stop(caesar_state->view_dispatcher);
  release_mutex((ValueMutex*)ctx, caesar_state);
  return true;
}

static void caesar_cipher_state_init(CaesarState* const caesar_state) {
  caesar_state->view_dispatcher = view_dispatcher_alloc();
  caesar_state->text_input = text_input_alloc();
  caesar_state->text_box = text_box_alloc();
  text_box_set_font(caesar_state->text_box, TextBoxFontText);
}

static void caesar_cipher_state_free(CaesarState* const caesar_state) {
  text_input_free(caesar_state->text_input);
  text_box_free(caesar_state->text_box);
  view_dispatcher_remove_view(caesar_state->view_dispatcher, 0);
  view_dispatcher_remove_view(caesar_state->view_dispatcher, 1);
  view_dispatcher_free(caesar_state->view_dispatcher);
  free(caesar_state);
}

int32_t caesar_cipher_app() {

  CaesarState* caesar_state = malloc(sizeof(CaesarState));
  
  FURI_LOG_D("caesar_cipher", "Running caesar_cipher_state_init");
  caesar_cipher_state_init(caesar_state);

  ValueMutex state_mutex;
  if(!init_mutex(&state_mutex, caesar_state, sizeof(CaesarState))) {
    FURI_LOG_E("caesar_cipher", "cannot create mutex\r\n");
    free(caesar_state);
    return 255;
  }

  FURI_LOG_D("caesar_cipher", "Assigning text input callback");
  text_input_set_result_callback(
    caesar_state->text_input,
    text_input_callback,
    &state_mutex,
    caesar_state->input,
    TEXT_BUFFER_SIZE,
    //clear default text
    true
  );
  text_input_set_header_text(caesar_state->text_input, "Input");

  // Open GUI and register view_port
  Gui* gui = furi_record_open("gui");
  //gui_add_view_port(gui, view_port, GuiLayerFullscreen);
  
  FURI_LOG_D("caesar_cipher", "Enabling view dispatcher queue");
  view_dispatcher_enable_queue(caesar_state->view_dispatcher);

  FURI_LOG_D("caesar_cipher", "Adding text input view to dispatcher");
  view_dispatcher_add_view(caesar_state->view_dispatcher, 0, text_input_get_view(caesar_state->text_input)); 
  view_dispatcher_add_view(caesar_state->view_dispatcher, 1, text_box_get_view(caesar_state->text_box)); 
  FURI_LOG_D("caesar_cipher", "Attaching view dispatcher to GUI");
  view_dispatcher_attach_to_gui(caesar_state->view_dispatcher, gui, ViewDispatcherTypeFullscreen);
  FURI_LOG_D("ceasar_cipher", "starting view dispatcher");
  view_dispatcher_set_navigation_event_callback(caesar_state->view_dispatcher, back_event_callback);
  view_dispatcher_set_event_callback_context(caesar_state->view_dispatcher, &state_mutex);
  view_dispatcher_switch_to_view(caesar_state->view_dispatcher, 0);
  view_dispatcher_run(caesar_state->view_dispatcher);

  furi_record_close("gui");
  delete_mutex(&state_mutex);
  caesar_cipher_state_free(caesar_state);

  return 0;
}