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


#include "hih61xx.h"
#include "deftypes.h"

extern uint16 devicef; 
extern void bus_err(int ern);
extern void print_help(void); 
unsigned char buf[5];
 
  

void hih61xx_print_all(void) 
{
    printf(
        "00: Relative Humidity [%%]     (reg: 0x00)\n"
        "01: Temperature       [°C]     (reg: 0x00)\n"
        "02: Status            [hex]    (reg: 0x00)\n"
        "\n");
}

void hih61xx_conf_set(const uchar *opts) {}


void hih61xx_get_data(void)                             //# Get measurement data from device
{
    buf[0] = 0x00;
    
    if(write(devicef, buf, 1) != 1){                     //# Start the measurement
        bus_err(errno);
    }

    usleep(60*1000);                                    //# Wait 60ms for measurement
    
    if(read(devicef, buf, 4) != 4){                     //# Read the data
        bus_err(errno);
    } 
}



unsigned char hih61xx_read_status(void){                 //# Get device status 
    return ((buf[0] & 0xc0) >> 6);          //# He ???  
}



float hih61xx_calc_humidity(float offset){              //# Measure
    unsigned int  raw = 0;
    float  humidity;
   
    if(hih61xx_read_status() != 0x01 )
    {
        raw = ((buf[0] & 0x3f) << 8) + buf[1];      // two msb status, 14bit data
        humidity = ((float)raw/(16384 - 2))*100;    // humidity = (14bit data / (2^14 -2)) * 100%
    }
    else
    {
        humidity = -1.0 ;
    }
    
    return (humidity + offset) ;
}



float hih61xx_read_temp(float offset)
{
    unsigned int  raw = 0;
    float  temp;
   
    if(hih61xx_read_status() != 0x01 )
    {
        raw = ((buf[2] << 8) + buf[1]) >> 2;        // 14bit temp data
        temp = ((float)raw/(16384 - 2))*165 - 40 ;    // temp = ((14bit data / (2^14 -2))*165) - 40 [°C] 
    }
    else
    {
        temp = -40.0 ;
    }
 
    return (temp + offset);
}



void hih61xx_read_all(const uchar *opts)
{
    hih61xx_get_data();
    
    if(opts != NULL)
    {
        char *ptr;
        printf("00:%f\n", hih61xx_calc_humidity(strtof((char*)opts, &ptr)));
        
        ptr++;               // One (,) character allowed for delimiter
        
        printf("01:%f\n", hih61xx_read_temp(strtof(ptr, NULL)));
    }     
    else
    {
        printf("00:%f\n", hih61xx_calc_humidity(0.0));
        printf("01:%f\n", hih61xx_read_temp(0.0));
    }     

    printf("02:0x%x\n", hih61xx_read_status()); 
  
}



void hih61xx_read_one(const uchar *opts)
{
    int id;
    char *ptr;
 
    hih61xx_get_data();
    id = strtol ((char*)opts,&ptr,0); //all format allowed
    ptr++;      //one separator allowed
        
    switch (id)
    {
        case 0x00:
            printf("00:%f\n", hih61xx_calc_humidity(strtof(ptr, NULL)));
            break;
        case 0x01:
            printf("01:%f\n", hih61xx_read_temp(strtof(ptr, NULL)));
            break;
        case 0x02:
            printf("02:0x%x\n", hih61xx_read_status()); 
            break;
        default:
            print_help();
    } 
}