#ifndef _MRBC_I2C_H
#define _MRBC_I2C_H

#include "mrbc_api.h"
#include "mrubyc.h"

#ifdef __cplusplus
extern "C" {
#endif
extern uint8_t * make_output_buffer(mrb_vm *vm, mrb_value v[], int argc,
                             int start_idx, int *ret_bufsiz);
#if !MRBC_USE_STRING
extern mrbc_value mrbc_array_new_alloc(mrbc_vm *vm, const uint8_t *c_array, int size);
#endif
#ifdef __cplusplus
}
#endif

void c_i2c_new(mrb_vm *vm, mrb_value *v, int argc){
#if defined(NO_I2C_HANDLE)
  void* handle = NULL;
#else
  v[0] = mrbc_instance_new(vm, v[0].cls, sizeof(I2C_HANDLE));
  int unit_num = 0;
  if( argc > 0 ) unit_num = GET_INT_ARG(1);
  MRBC_KW_ARG( unit );
  if( MRBC_KW_ISVALID(unit) ) unit_num = mrbc_integer(unit);
  MRBC_KW_DELETE( unit );
  I2C_HANDLE *handle = (I2C_HANDLE *)v[0].instance->data;
  handle->unit_num = unit_num;
#endif
  int scl=-1,sda=-1;
  uint32_t freq_num=100000;
  MRBC_KW_ARG(frequency, freq, scl_pin, sda_pin);
  if( MRBC_ISNUMERIC(scl_pin) )
    scl = MRBC_TO_INT(scl_pin);
  if( MRBC_ISNUMERIC(sda_pin) )
    sda = MRBC_TO_INT(sda_pin);
  //MRBC_KW_ARG(frequency, freq);
  if( MRBC_ISNUMERIC(frequency) )
    freq_num = MRBC_TO_INT(frequency);
  if( MRBC_ISNUMERIC(freq) )
    freq_num = MRBC_TO_INT(freq);
  mrbcI2cInit(handle, freq_num, scl, sda);
  MRBC_KW_DELETE(frequency, freq, scl_pin, sda_pin);
  //MRBC_KW_DELETE(frequency, freq);
}

void c_i2c_write(mrb_vm *vm, mrb_value *v, int argc){
#if defined(NO_I2C_HANDLE)
  void* handle = NULL;
#else
  I2C_HANDLE *handle = (I2C_HANDLE *)v[0].instance->data;
#endif
  uint8_t *buf = 0;
  int size = 0;
  if( argc>0 ){
    uint8_t adrs = GET_INT_ARG(1);
    mrbcI2cStart(handle, adrs, 0);
    if(argc>1){
      buf = make_output_buffer( vm, v, argc, 2, &size );
      mrbcI2cWrite(handle, buf, size);
      mrbc_free( vm, buf );
    }
    mrbcI2cStop(handle);
  }
  SET_RETURN( mrbc_integer_value(size) );
}

void c_i2c_read(mrb_vm *vm, mrb_value *v, int argc){
#if defined(NO_I2C_HANDLE)
  void* handle = NULL;
#else
  I2C_HANDLE *handle = (I2C_HANDLE *)v[0].instance->data;
#endif
  uint8_t *buf = 0;
  int size = 0;
  mrbc_value ret = mrbc_nil_value();
  if( argc>1 ){
    int adrs = GET_INT_ARG(1);
    int len = GET_INT_ARG(2);
    if( argc > 2 ) {
      mrbcI2cStart(handle, adrs, 0);
      buf = make_output_buffer( vm, v, argc, 3, &size );
      mrbcI2cWrite(handle, buf, size);
      mrbc_free( vm, buf );
    }
    buf = (uint8_t*) mrbc_alloc(vm, len);
    mrbcI2cStart(handle, adrs, len); // len>0 in read mode
    mrbcI2cRead(handle, buf, len);
#if MRBC_USE_STRING
    ret = mrbc_string_new_alloc(vm, buf, len);
#else
    ret = mrbc_array_new_alloc( vm, buf, len);
    mrbc_free( vm, buf );
#endif
  }
  SET_RETURN(ret);
}

void mrbc_init_class_i2c(void){
  mrb_class *i2c = mrbc_define_class(0, "I2C",  mrbc_class_object);
  mrbc_define_method(0, i2c, "new", c_i2c_new);
  mrbc_define_method(0, i2c, "read", c_i2c_read);
  mrbc_define_method(0, i2c, "write", c_i2c_write);
}

#endif