slik-dispenser/arduino/state.ino

#define INPUT_SIZE 4

enum state current_state;
char input_code[INPUT_SIZE];

bool is_input_empty()
{
	for (int i = 0; i < INPUT_SIZE; i++) {
		if (input_code[i]) return false;
	}
	return true;
}

void change_state(enum state new_state)
{
	// Initialize state
	switch (new_state) {
		case STATE_INPUT_PASSCODE:
			input_code[0] = '\0';
			input_code[1] = '\0';
			input_code[2] = '\0';
			input_code[3] = '\0';
			break;
	}

	current_state = new_state;
	draw_state();
}

void draw_state()
{
	carrier.display.fillScreen(0x000);

	switch (current_state) {
		case STATE_CONNECTING:
			carrier.display.setCursor(20, 100);
			carrier.display.setTextSize(3);
			carrier.display.print("Connecting..");
			break;

		case STATE_LOGGED_OUT:
			carrier.display.setCursor(15, 100);
			carrier.display.setTextSize(2);
			carrier.display.print("Press Green Button");
			carrier.leds.fill(green_led_color, 2, 1);
			carrier.leds.setBrightness(5);
			carrier.leds.show();
			break;
		case STATE_INPUT_PASSCODE:
			if (is_input_empty()) {
				carrier.display.setCursor(50, 100);
				carrier.display.setTextSize(2);
				carrier.display.print("Please enter");
				carrier.display.setCursor(80, 120);
				carrier.display.print("passcode");
			} else {
				carrier.display.setCursor(50, 100);
				carrier.display.setTextSize(3);
				for (int i = 0; i < INPUT_SIZE; i++) {
					char ch = input_code[i];
					if (!ch) ch = '_';

					carrier.display.print(ch);
					carrier.display.print(' ');
				}
			}
			break;
	}
}

void loop_state()
{
	switch (current_state) {
		case STATE_LOGGED_OUT:
			if (carrier.Buttons.onTouchDown(TOUCH2)) {
				change_state(STATE_INPUT_PASSCODE);
			}
			break;
		case STATE_INPUT_PASSCODE:
			touchButtons buttons[] = { TOUCH0, TOUCH1, TOUCH3, TOUCH4 };
			char input_characters[] = "1234";

			for (int i = 0; i < sizeof(buttons) / sizeof(buttons[0]); i++) {
				if (carrier.Buttons.onTouchDown(buttons[i])) {
					
					for (int j = 0; j < sizeof(input_code); j++) {
						if (!input_code[j]) {
							input_code[j] = input_characters[i];
							break;
						}
					}

					draw_state();

					break;
				}
			}

			break;
	};
}