#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <fcntl.h>
#include <errno.h> 
#include <unistd.h>


#include <linux/i2c-dev.h>
#include <linux/i2c.h>
#include <sys/ioctl.h>
  
#include "deftypes.h"  
#include "lm75.h"
#include "hih61xx.h"
#include "hmc5883.h"

#define VERSION 1.27
#ifndef _BUILD_TIME_
    #define _BUILD_TIME_ __DATE__" "__TIME__ 
#endif

// extern void lm75_print_help(void);
// extern void lm75_read_all(const char *opts);
// extern void lm75_read_one(const char *opts);
// extern void hih61xx_print_help(void);
// extern void hih61xx_read_all(const char *opts); 
// extern void hih61xx_read_one(const char *opts);



uint16 devicef;    //# Bus-Device file 
uchar temp[256];
void (*print_all)(void) = NULL;
void (*read_all)(const uchar *opts) = NULL;
void (*read_one)(const uchar *opts) = NULL;
void (*conf_set)(const uchar *opts) = NULL;


void print_help(void) {  
    printf ("\n"
            "   i2sensors  <op> <bus> <dev_type> <dev_addr> (<options>)\n"
            "\n"
            "Aviable options: <op>\n"
            "   print_all   -- list all available measurement parameters of the device\n"
            "   read_all    -- read all measured parameters from device\n"
            "   read_one    -- read the selected parameters from device\n"
            "   read_repeat -- read measurements continously\n"
            "   conf_set    -- set the configuration register\n"
            "\n"
            "Usage:\n"
            "   i2sensors read_all <bus> <device-type> <address> \n"
            "   i2sensors read_one <bus> <device-type> <address> <param-id,offset_for_param>\n"
            "   i2sensors conf_set <bus> <device-type> <address> <reg-id,word-of-bits>\n"
            "\n"
            "Examples:\n"
            "   i2sensors read_all 1 lm75 0x4f \n"
            "   i2sensors read_one 1 lm75 0x4f  00,-1.35\n"
            "\n" );
    printf ("Version:  v%1.2f,  build: [%s] (gcc %s) \n\n",VERSION,_BUILD_TIME_,__VERSION__);
}

void bus_err(int ern){
    //printf("I2C communication(rd) error. errno: %d\n",errno);
    fprintf (stderr, "Internal error %d at %s, line %d. (function: %s/%s)\n", ern, __FILE__, __LINE__, __func__, __FUNCTION__);
}
void bus_errr(int ern){
    //printf("I2C communication(rd) error. errno: %d\n",errno);
    fprintf (stderr, "Internal error %d at %s, line %d. (function: %s/%s)\n", errno, __FILE__, __LINE__, __func__, __FUNCTION__);
}

uchar   *xchg_data  (uchar *buf, uint16 wrlen, uint16 waitlen, uint16 rdlen){                     //# [buf] = 32 byte         

	if(write(devicef, buf, 1) != 1){                //# write one byte to device
        perror("I2C communication(wrr) error.");
        fprintf (stderr, "I2C error (WR) %d at %s, line %d. (function: %s/%s)\n", errno, __FILE__, __LINE__, __func__, __FUNCTION__);
        bus_err(errno);
        bus_errr(0);
    }
    usleep(waitlen*1000);                                //# Wait 10ms for reading

    if(read(devicef, buf, rdlen) != rdlen) {                //# read the result
        perror("I2C communication(rd) error.");
        fprintf (stderr, "I2C error (WR) %d at %s, line %d. (function: %s/%s)\n", errno, __FILE__, __LINE__, __func__, __FUNCTION__);
        bus_err(errno);
        bus_errr(0);
    }
    return buf; 
}


void preinit(const uchar *dev_type){

    if(!strcmp("lm75", (char *)dev_type)){
        print_all = lm75_print_all;
        read_all = lm75_read_all;
        read_one = lm75_read_one;
        conf_set = lm75_conf_set;
    }

    else if(!strcmp("hih61xx", (char *)dev_type)) {                            
        print_all = hih61xx_print_all;
        read_all = hih61xx_read_all;
        read_one = hih61xx_read_one;
        conf_set = hih61xx_conf_set;
    }

    // else if(!strcmp("hmc5883", dev_type)) {                            
    //     print_all = hmc5883_print_all;
    //     read_all = hmc5883_read_all;
    //     read_one = hmc5883_read_one;
    //     conf_set = hmc5883_conf_set;
    // }
}



int main(int argc, char *argv[])
{
    
// >> i2sensor <op> <bus> <dev_typ> <dev_addr> (<others>) 
// >> i2sensor read_all 0 lm75 4f 1,-1.0;2,+0.2;3,+10;4,-2
//    read_all, list_all, 
//    ...read_all...<dev_addr>, <param_id,offs,param_id,offs>    
//    read_one...<dev_addr>, <param_id,offs>    
//    ...read_reg_hex... <dev_addr>, <reg_addr,b/w/dw> 
//    ...read_reg_dec... <dev_addr>, <reg_addr,b/w/dw>
//    ...set_param... <dev_addr>, <param_id,value_dec>
//    ...set_reg... <dev_addr>, <reg_addr,value_hex>    
    

    if(4 < argc && argc < 10)                                           //Minimum 5 arguments should be passed.
    {
        
        char filename[32];
        int i;
        preinit((uchar *)argv[3]);

        for( i = 0;  i < strlen(argv[2]);  i++){                        //# Test on bus address, for error detection.
            if(!isdigit(argv[2][i])){
                printf("\n\tThe BUS Address must be an integer!\n\n");
                print_help();
                exit (EXIT_FAILURE);
            }
        }
        snprintf(filename, 31, "/dev/i2c-%s", argv[2]);   
        devicef = open(filename, O_RDWR);                               //# Open the i2c bus 
    
        if (devicef < 0){
            printf("\n\tCan't open i2c BUS. Have you any permission?\n\n");    
            print_help();
            exit (EXIT_FAILURE);
        }


        if(argv[4][0]=='0' && argv[4][1]=='x'){                         //# Hexadecimal representetion of device address

            long addr = (int)strtol(argv[4], NULL, 0);                  //# strtol() is working with hex-string correctly

            if (ioctl(devicef, I2C_SLAVE, addr) < 0){                    //# Seeking/Opening the device on the Bus
                printf("\n\tCan't open i2c DEVICE, errno: %d\n\n",errno);
                print_help();
                exit (EXIT_FAILURE);
            }
        } else {
            printf("\n\tThe DEVICE address must be a hexadecimal number\n\n");
            print_help();
            exit (EXIT_FAILURE);
        }
        
        
        
        if(!strcmp("print_all",argv[1]) && print_all != NULL){          //# Gets the device's help message.
            print_all();
        }
        else if(!strcmp("read_all",argv[1]) && read_all != NULL){       //# Pulls all readable registers data from device
            // read_all(argv[5]);
            read_all(NULL);
        }
        else if(!strcmp("read_one",argv[1]) && read_one != NULL && argc > 5)    //# Prints out the selected register
        {
            read_one((uchar*)argv[5]);
        }
        else if(!strcmp("conf_set",argv[1]) && conf_set != NULL && argc > 5)    //# Prints out the selected register
        {
            conf_set((uchar*)argv[5]);
        }
        else                                                            //# No other option
        { 
            print_help();
        }
    
	close(devicef);
  
  }
  else
  {
    print_help();
  }
  return 0;
}