#include <ch.h>
#include <hal.h>
#include "buttons.h"

static btn_hndlr btnh[Button_Num];

/* Constants */
static const ioline_t button_Lines[Button_Num] = {
  LINE_BTN_1, LINE_BTN_2, LINE_BTN_3, LINE_BTN_4
}; /* from board.h */

/* Variables */
static binary_semaphore_t btn_bsem;
static virtual_timer_t button_vt;
static button_state_t button_States[Button_Num] = {0};
static uint8_t button_Time[Button_Num] = {0};

/* Functions */
static void button_Process(virtual_timer_t *vtp, void *p) {
  (void)vtp;
  (void)p;

  /* Entering I-Locked state and signaling the semaphore.*/
  chSysLockFromISR();
  chBSemSignalI(&btn_bsem);
  chSysUnlockFromISR();
}

/*
 * BTN serving thread.
 */
static THD_WORKING_AREA(waBTNThread, 256);
static THD_FUNCTION(BTNThread, arg) {
  (void)arg;
  static int pause = 0;

  while (true) {
    /* Waiting for an binary semaphore. */
    chBSemWait(&btn_bsem);

    if (pause != 0) {
      pause --;
    } else {

      int i;
      for (i=0; i<Button_Num; i++) {

        if (palReadLine(button_Lines[(button_num_t)i]) == BUTTON_PRESSED) {
        /* button pressed */
          button_Time[i] ++;
          if (button_Time[i] >= BTN_TIME_HOLDED) {
            /* process long press */
            button_Time[i] -= BTN_TIME_REPEATED;
            button_States[i] = BTN_st_Holded;
            btnh[i](BTN_st_Pressed); // autorepeat
          }

        } else if (button_Time[i] != 0) {
        /* button released */
          if (button_Time[i] >= BTN_TIME_PRESSED) {
            /* process short press */
            button_States[i] = BTN_st_Pressed;
            btnh[i](BTN_st_Pressed);
          }
          button_Time[i] = 0;
          button_States[i] = BTN_st_Released;
          pause = BTN_SCAN_PAUSE;
          //btnh[i](BTN_st_Released);
        }
      } /* end FOR */
    } /* end Pause check */
  } /* end WHILE */
}

void buttons_Init(btn_hndlr ha[]) {
  btnh[Button1] = ha[Button1];
  btnh[Button2] = ha[Button2];
  btnh[Button3] = ha[Button3];
  btnh[Button4] = ha[Button4];

  /* Initializing the Button semaphore in the "taken" state. */
  chBSemObjectInit(&btn_bsem, true);

  /* Starting the Button thread. */
  chThdCreateStatic(waBTNThread, sizeof(waBTNThread), NORMALPRIO, BTNThread, NULL);

  /* Starting a virtual timer ticking the thread. */
  chVTSetContinuous(&button_vt, TIME_MS2I(BTN_SCAN_PERIOD), button_Process, NULL);
}

button_state_t buttons_GetState(const button_num_t btn) {
  return button_States[btn];
}