// Copyright (c) 2015, XMOS Ltd, All rights reserved

#include <xs1.h>
#include <platform.h>
#include <gpio.h>

// GPIO port declarations
on tile[0] : in port explorer_buttons = XS1_PORT_4E;
on tile[0] : out port explorer_leds = XS1_PORT_4F;

// GPIO handler routine
void gpio_handler(client input_gpio_if button_1, client input_gpio_if button_2,
                  client output_gpio_if led_green, client output_gpio_if rgb_led_blue,
                  client output_gpio_if rgb_led_green, client output_gpio_if rgb_led_red) {

  // LED state
  unsigned int green_led_state = 0;
  unsigned int rgb_led_state = 0;

  // Initial button event state, active low
  button_1.event_when_pins_eq(0);
  button_2.event_when_pins_eq(0);

  while (1) {
    select {
      // Triggered by events on button 1
      case button_1.event():
        if (button_1.input() == 0) {
          green_led_state = ~green_led_state;
          led_green.output(green_led_state);
          // Set button event state to active high for debounce
          button_1.event_when_pins_eq(1);
        } else {
          // Debounce button
          delay_milliseconds(50);
          button_1.event_when_pins_eq(0);
        }
        break;

      // Triggered by events on button 2
      case button_2.event():
        if (button_2.input() == 0) {
          rgb_led_red.output(0);
          rgb_led_green.output(0);
          rgb_led_blue.output(0);
          rgb_led_state++;
          rgb_led_state %= 4;

          switch (rgb_led_state) {
            case 1:
              rgb_led_red.output(1);
              break;
            case 2:
              rgb_led_green.output(1);
              break;
            case 3:
              rgb_led_blue.output(1);
              break;
          }
          // Set button event state to active high for debounce
          button_2.event_when_pins_eq(1);
        } else {
          // Debounce button
          delay_milliseconds(50);
          button_2.event_when_pins_eq(0);
        }
        break;
    }
    // end of event select
  }

}

// The main() function runs a single task which takes the gpio interfaces as parameters
int main() {
  input_gpio_if i_explorer_buttons[2];
  output_gpio_if i_explorer_leds[4];
 
  par {
     on tile[0] : input_gpio_with_events(i_explorer_buttons, 2, explorer_buttons, null);
     on tile[0] : output_gpio(i_explorer_leds, 4, explorer_leds, null);
     on tile[0] : gpio_handler(i_explorer_buttons[0], i_explorer_buttons[1],
                               i_explorer_leds[0], i_explorer_leds[1],
                               i_explorer_leds[2], i_explorer_leds[3]);
  } 

   return 0;
}