#include "project.h"

#define BUFFER_SIZE 32

#define TIMEOUT 500
#define SLEEPY 550
#define BACKOFF 200

#define N_CMDS	4

static char modem_buf[BUFFER_SIZE];
static unsigned modem_ptr;
static char *modem_cmds[N_CMDS];
static int modem_cmds_ptr;
static int timeout;
static int sleepy = SLEEPY;

int in_call;
int dialtone;



void
modem_send (void)
{
  if (!modem_cmds_ptr) return;

  if (sleepy >= SLEEPY)
    {
      printf ("modem is sleepy\r\n");
      usart2_queue ('\r');
      sleepy = 0;
      timeout = BACKOFF;
      return;
    }
  sleepy = 0;

  printf ("(re)send %s\r\n",modem_cmds[0]);
  timeout = TIMEOUT;
  usart2_queue ('\r');
  usart2_tx (modem_cmds[0], strlen (modem_cmds[0]));
  usart2_queue ('\r');
}

void modem_cmd(char *buf)
{
if (modem_cmds_ptr==N_CMDS) return;

modem_cmds[modem_cmds_ptr]=buf;
modem_cmds_ptr++;

if (modem_cmds_ptr==1) modem_send();

}

void modem_dial	(char *buf) {
in_call=1;
modem_cmd(buf);
}



void modem_tone_off()
{
//  modem_cmd ("AT+STTONE=0");
modem_cmd("AT+SIMTONE=1,400,200,0,10");
}

void modem_tone(int i)
{
static char tone[]={'A','T','+','S','T','T','O','N','E','=','1',',','0','0',',','4','5','0','0','0',0};

tone[12]='0'+(i/10);
tone[13]='0'+(i%10);

modem_cmd(tone);
}

void modem_tone_nu(void)
{
modem_cmd("AT+SIMTONE=1,400,200,0,45000");
}



void
modem_line ()
{
  int i;

  printf ("Modem said: %s\r\n", modem_buf);

  sleepy = 0;

  if (!strncmp (modem_buf, "RDY", 4))
    {
      modem_cmd ("ATZ");
      modem_cmd ("AT+CALM=1");
      modem_cmd ("AT+CLVL=90");
    }
  else
   if (!strncmp (modem_buf, "RING", 4))
    {
      dialstr_clear ();
      dialtone = 0;
      if (!hook)
        {
          answer_call ();
        }
      else
        {
          ringer_ring (4000);
        }
    }
  else
   if (!strncmp (modem_buf, "OK", 2) || !strncmp (modem_buf, "ERROR", 2))
    {
     if (modem_cmds_ptr) {

      for (i=1;i<modem_cmds_ptr;++i) {
	modem_cmds[i-1]=modem_cmds[i];
      }
	modem_cmds_ptr--;
	modem_cmds[modem_cmds_ptr]=NULL;

      timeout = 0;

	if (modem_cmds_ptr) modem_send();
    }
  }
  else
   if (!strncmp (modem_buf, "NO CARRIER", 10)) {
        in_call=0;
	if (!hook) 
   	  modem_tone_nu();
   }
}

void
modem_byte (uint8_t b)
{

  if (b == '\n')
    return;

  if (b == '\r')
    {
      if (modem_ptr)
        modem_line ();
      modem_ptr = 0;
      modem_buf[modem_ptr] = 0;
      return;
    }

  if (modem_ptr >= (sizeof (modem_buf) - 1))
    return;

  modem_buf[modem_ptr] = b;
  modem_ptr++;
  modem_buf[modem_ptr] = 0;
}

void
answer_call (void)
{
  printf ("Answering call\r\n");
  dialtone = 0;
  modem_cmd ("ATA");
  in_call=1;
}

void
terminate_call (void)
{
  printf ("Terminating any call\r\n");
  modem_cmd ("ATH0");
  in_call=0;
}

void
dialtone_on (void)
{
  dialtone = 1;
  modem_tone(20);
}

void
dialtone_off (void)
{
  if (!dialtone)
    return;
  modem_tone_off();

  dialtone = 0;
}


void
modem_tick (void)
{

  if (sleepy < SLEEPY)
    sleepy++;

  if (!timeout)
    return;
  timeout--;
  if (timeout)
    return;

  modem_send ();
}

void
modem_init (void)
{
}