//
// Serial Receive Program
//
// cc -o sirexec sirexec.c -lwiringPi
//
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <linux/ipc.h>
#include <linux/msg.h>
#include <sys/types.h>
#include <wiringPi.h>
#include <wiringSerial.h>

#define DEBUG    0
#define BAUDRATE 4800
#define	INTERVAL 0

// Re define message structure
typedef struct mymsgbuf
{
  long mtype;
  long code;
} mess_t;

typedef struct {
  long code;
  char* command;
} keymap;


//
// get IR code
//
// 1,XXXXXX->0
// 0,abcdef->0xabcdef
//
long getIR(char * buf) {
  char work[10];
  char *endptr;
  long x1,x2,x3;

  if (buf[0] == '1') return 0;
  memset(work,0,sizeof(work));
  memcpy(work,&buf[2],4);
  x1=strtol(work, &endptr, 16);
//  printf("x1=%x\n",x1);
  memcpy(work,&buf[6],4);
  x2=strtol(work, &endptr, 16);
//  printf("x2=%x\n",x2);
  x3=(x1<<16)+x2;
//  printf("x3=%x\n",x3);
  return x3;
}


int loadconfig(char * path, keymap * map)
{
  FILE* fp;
  int read;
  char* line = NULL;
  char* tmp;
  size_t alloc;
  int i = 0;
  char work[10];
  char *endptr;
  long x1,x2,x3;

  fp = fopen(path, "r");
  if (fp == NULL) return -1;

  while ((read = getline(&line, &alloc, fp)) != -1) {
//    printf("read=%d\n",read);
    if (read <= 1) continue;
    line[read-1]=0;
//    printf("line=[%s]\n",line);
    if (line[0] == '#') continue;

    /* fetch keycode*/
    memcpy(work,&line[0],4);
    x1=strtol(work, &endptr, 16);
//    printf("x1=%x\n",x1);
    memcpy(work,&line[4],4);
    x2=strtol(work, &endptr, 16);
//    printf("x2=%x\n",x2);
    x3=(x1<<16)+x2;
//    printf("x3=%x\n",x3);
    map[i].code = x3;

    /* fetch keycode*/
    tmp = strtok(line, ",");
    if (tmp == NULL) continue;

    /* and command */
    tmp = strtok(NULL, ",");
    map[i].command = tmp;
//    printf("map[%d].command=[%s]\n",i,map[i].command);

    /* cleanup for next pass */
    i++;
    line = NULL;
  }
  fclose(fp);
  return i;
}


int readSerial(int fd, char * buff, int blen, int timeout) {
  unsigned long endTime;
  int ch;
  int pos = 0;

if(DEBUG)printf("millis=%d\n",millis());
  endTime = millis () + timeout;
if(DEBUG)printf("endTime=%d\n",endTime);
  buff[pos] = 0;

  while (1) {
    if (millis () > endTime) return -1;
    if (serialDataAvail (fd)) {
      ch = serialGetchar (fd);
if(DEBUG)printf (" -> %02x\n", ch);
      if (ch == 0x0d) {

      } else if (ch == 0x0a) {
        return pos;
      } else {
        if (pos < blen) buff[pos++] = ch;
        if (pos < blen) buff[pos] = 0;
      }
    } // end if
  } // end while
}


int main(int argc, char **argv)
{
  int qid;
  key_t msgkey;
  pid_t pid;

  mess_t buf;

  int msglen;
  int cont;

  char *device;
  char *config;
  int readlen;
  char buff[64];

  keymap map[255] = {0};
  int maps;
  int i;
 
  int fd;
  long ircode;
  long savecode=0;

  int beDebug = 0;

  if (argc < 2) {
    printf("%s /dev/ttyS config\n",argv[0]);
    return 0;
  }
  device=argv[1];
  config=argv[2];
  if (argc == 4) {
    if (strcmp(argv[3],"debug") == 0) beDebug = 1;
  }
  if(beDebug)printf("device=[%s] config=[%s] beDebug=%d\n",device,config,beDebug);
  if (getuid() != 0)
    printf("You are not root! This may not work...\n");
//  if (beDaemon) daemon(0,0);

  maps=loadconfig(config,map);
if(DEBUG)printf("maps=%d\n",maps);
  if (maps <= 0) {
    printf("Error:llegal config file\n");
    return 0;
  }
  for(i=0;i<maps;i++) {
if(DEBUG)printf("code=%x command=[%s]\n",map[i].code,map[i].command);
  }

  msgkey = ftok(".",'m');
//  printf("msgkey=%x\n",msgkey);
  msglen = sizeof(mess_t) - sizeof(long);
  qid = msgget(msgkey, IPC_CREAT | 0660);

  if(!(pid = fork())){
//    printf("SON - QID = %d\n", qid);

    if ((fd = serialOpen (device, BAUDRATE)) < 0) {
      printf ("Unable to open serial device: %s\n", strerror (errno)) ;
      return 1 ;
    }

    if (wiringPiSetup () == -1) {
      printf ("Unable to start wiringPi: %s\n", strerror (errno)) ;
      return 1 ;
    }

    while(1) {
    //Receive data
      readlen=readSerial(fd, buff, sizeof(buff),1000);
if(DEBUG)printf("readSerial=%d\n",readlen);
      if (readlen != -1) { // read data
if(DEBUG)printf("readSerial buff=[%s]\n",buff);
        ircode=getIR(buff);
if(DEBUG)printf("ircode=%x savecode=%x\n",ircode,savecode);
        if (ircode == 0) continue;
        if (ircode == savecode) continue;

        buf.mtype = 1;
        buf.code = ircode;
        msgsnd(qid, &buf, msglen, 0);
        if(beDebug)printf("SON - MESSAGE=%x\n", buf.code);
        savecode=ircode;
      } else { // timeout
        savecode=0;
      }
    }

    return 0;
  }

//  printf("FATHER - QID = %d\n", qid);

  while(1){
    msgrcv(qid, &buf, msglen, 1, 0);
    if(beDebug)printf("FATHER - MESSAGE=%x\n", buf.code);
    for(i=0;i<maps;i++) {
if(DEBUG)printf("code=%x command=[%s]\n",map[i].code,map[i].command);
      if (buf.code == map[i].code) {
        if(beDebug)
        printf("execute command=[%s]\n",map[i].command);sleep(1);
        system(map[i].command);
      }
    }
    if(INTERVAL > 0) sleep(INTERVAL);
  }

  msgctl(qid, IPC_RMID, 0);

  return 0;
}