/*
 * Project: nRF905 AVR/Arduino Library/Driver
 * Author: Zak Kemble, contact@zakkemble.co.uk
 * Copyright: (C) 2013 by Zak Kemble
 * License: GNU GPL v3 (see License.txt)
 * Web: http://blog.zakkemble.co.uk/nrf905-avrarduino-librarydriver/
 */

#ifndef NRF905_H_
#define NRF905_H_

#include <Arduino.h>
#include "nRF905_config.h"

//#define nRF905_packet nrf905_packet_s;

/**
 * \enum nRF905_radio_state_t 
 * \brief Radio state
 */
typedef enum
{
	NRF905_RADIO_STATE_POWER_DOWN,	/**< Power down mode */
	NRF905_RADIO_STATE_STANDBY,		/**< standby mode*/
	NRF905_RADIO_STATE_RX,			/**< Receive mode */
	NRF905_RADIO_STATE_RX_END,		/**< Received data available */
	NRF905_RADIO_STATE_TX,			/**< Transmitting started */
	NRF905_RADIO_STATE_TX_END,		/**< Transmitting finished */
} nRF905_radio_state_t;

/**
 * \enum nRF905_band_t 
 * \brief Frequency bands.
 */
typedef enum
{
// NOTE:
// When using NRF905_BAND_868 and NRF905_BAND_915 for calculating channel (NRF905_CALC_CHANNEL(f, b)) they should be value 0x01,
// but when using them for setting registers their value should be 0x02.
// They're defined as 0x02 here so when used for calculating channel they're right shifted by 1

	NRF905_BAND_433 = 0x00,	/**< 433MHz band */
	NRF905_BAND_868 = 0x02,	/**< 868MHz band */
	NRF905_BAND_915 = 0x02	/**< 915MHz band */
} nRF905_band_t;

/**
 * \enum nRF905_pwr_t 
 * \brief Output power (n means negative, n10 = -10).
 */
typedef enum
{
	NRF905_PWR_n10 = 0x00,	/**< -10dBm = 100uW */
	NRF905_PWR_n2 = 0x04,	/**< -2dBm = 631uW */
	NRF905_PWR_6 = 0x08,	/**< 6dBm = 4mW */
	NRF905_PWR_10 = 0x0C	/**< 10dBm = 10mW */
} nRF905_pwr_t;

/**
 * \enum nRF905_low_rx_t 
 * \brief Save a few mA by reducing receive sensitivity.
 */
typedef enum
{
	NRF905_LOW_RX_DISABLE = 0x00,	/**< Disable low power receive */
	NRF905_LOW_RX_ENABLE = 0x10		/**< Enable low power receive */
} nRF905_low_rx_t;

/**
 * \enum nRF905_auto_retran_t 
 * \brief Constantly retransmit payload while in transmit mode.
 *
 * Can be useful in areas with lots of interference, but you'll need to make sure you can differentiate between re-transmitted packets and new packets (like an ID number).
 *
 * Other transmissions will be blocked if collision avoidance is enabled.
 */
typedef enum
{
	NRF905_AUTO_RETRAN_DISABLE = 0x00,	/**< Disable auto re-transmit */
	NRF905_AUTO_RETRAN_ENABLE = 0x20	/**< Enable auto re-transmit */
} nRF905_auto_retran_t;

/**
 * \enum nRF905_outclk_t 
 * \brief Output a clock signal on pin 3 of IC.
 */
typedef enum
{
	NRF905_OUTCLK_DISABLE = 0x00,	/**< Disable output clock */
	NRF905_OUTCLK_4MHZ = 0x04,		/**< 4MHz clock */
	NRF905_OUTCLK_2MHZ = 0x05,		/**< 2MHz clock */
	NRF905_OUTCLK_1MHZ = 0x06,		/**< 1MHz clock */
	NRF905_OUTCLK_500KHZ = 0x07,	/**< 500KHz clock */
} nRF905_outclk_t;

/**
 * \enum nRF905_crc_t 
 * \brief CRC Checksum.
 */
typedef enum
{
	NRF905_CRC_DISABLE = 0x00,	/**< Disable CRC */
	NRF905_CRC_8 = 0x40,		/**< 8bit CRC */
	NRF905_CRC_16 = 0xC0,		/**< 16bit CRC */
} nRF905_crc_t;

/**
 * \enum nRF905_addr_size_t 
 * \brief Address size.
 */
typedef enum
{
	NRF905_ADDR_SIZE_1 = 0x01,	/**< 1 byte */
	NRF905_ADDR_SIZE_4 = 0x04,	/**< 4 bytes */
} nRF905_addr_size_t;

// Setting options
//#define NRF905_BAND_433			0x00
//#define NRF905_BAND_868			0x02
//#define NRF905_BAND_915			0x02
//#define NRF905_PWR_n10			0x00
//#define NRF905_PWR_n2			0x04
//#define NRF905_PWR_6			0x08
//#define NRF905_PWR_10			0x0C
//#define NRF905_LOW_RX_ENABLE	0x10
//#define NRF905_LOW_RX_DISABLE	0x00
//#define NRF905_AUTO_RETRAN_ENABLE	0x20
//#define NRF905_AUTO_RETRAN_DISABLE	0x00
//#define NRF905_OUTCLK_DISABLE	0x00
//#define NRF905_OUTCLK_4MHZ		0x04
//#define NRF905_OUTCLK_2MHZ		0x05
//#define NRF905_OUTCLK_1MHZ		0x06
//#define NRF905_OUTCLK_500KHZ	0x07
//#define NRF905_CRC_DISABLE		0x00
//#define NRF905_CRC_8			0x40
//#define NRF905_CRC_16			0xC0
//#define NRF905_ADDR_SIZE_1		0x01
//#define NRF905_ADDR_SIZE_4		0x04

/**
* Maximum payload size
*/
#define NRF905_MAX_PAYLOAD		32

void nRF905_setConfigReg0(uint8_t value);
void nRF905_setConfigReg1(uint8_t value);
void nRF905_setConfigReg2(uint8_t value);
void nRF905_setConfigReg9(uint8_t value);
void nRF905_flushRecBuffer(void);
uint8_t nRF905_getConfigReg(uint8_t reg);
nRF905_radio_state_t nRF905_getStatus(void);


/**
* Initialise, must be called before anything else!
*
* @return (none)
*/
void nRF905_init(void);

/**
* Set frequency, workout the channel from the frequency
*
* 433MHz band: 422.4MHz - 473.5MHz, 100KHz steps
*
* 868/915MHz band: 844.8MHz - 947MHz, 200KHz steps
*
* @param [band] Frequency band
* @param [freq] Frequency in Hz
* @return (none)
*/
void nRF905_setFrequency(nRF905_band_t band, uint32_t freq);

/**
* Just set the channel, this skips having to workout the channel from the frequency
*
* @param [band] Frequency band
* @param [channel] The channel (0 - 511)
* @return (none)
*/
void nRF905_setChannel(nRF905_band_t band, uint16_t channel);

#if 0
/**
* Set auto retransmit
*
* @param [val] Enable/disable auto retransmit
* @return (none)
*/
void nRF905_setAutoRetransmit(nRF905_auto_retran_t val);

/**
* Set low power receive
*
* @param [val] Enable/disable low power receive
* @return (none)
*/
void nRF905_setLowRxPower(nRF905_low_rx_t val);

/**
* Set output power
*
* @param [val] Output power level
* @return (none)
*/
void nRF905_setTransmitPower(nRF905_pwr_t val);

/**
* Set CRC
*
* @param [val] CRC Type
* @return (none)
*/
void nRF905_setCRC(nRF905_crc_t val);

/**
* Set clock output
*
* @param [val] Clock out frequency
* @return (none)
*/
void nRF905_setClockOut(nRF905_outclk_t val);
#endif

/**
* Payload size
*
* @param [size] Payload size (1 - 32)
* @return (none)
*/
void nRF905_setPayloadSizes(uint8_t size);

//**
//* Address size
//*
//* @param [size] Address size
//* @return (none)
//*/
//void nRF905_setAddressSize(nRF905_addr_size_t size);

/**
* Destination radio address
*
* @param [address] The address (usually a byte array of 1 or 4 bytes depending on NRF905_ADDR_SIZE)
* @return (none)
*/
void nRF905_setTXAddress(uint8_t * address);

/**
* Address of this radio
*
* @param [address] The address (usually a byte array of 1 or 4 bytes depending on NRF905_ADDR_SIZE)
* @return (none)
*/
void nRF905_setRXAddress(uint8_t * address);

/**
* Set payload data
*
* @param [data] Pointer to data
* @param [len] How many bytes to copy (max NRF905_MAX_PAYLOAD)
* @return false if the radio is currently transmitting something else, true otherwise
*/
uint8_t nRF905_setData(uint8_t * data, uint8_t len);

/**
* Send the payload.
*
* @return false if other transmissions are going on and collision detection is enabled or if the radio is currently transmitting, true if transmission has successfully began
*/
uint8_t nRF905_send(void);

// 
//bool nRF905_sendPacket(nrf905_packet_s*);

/**
* Get current radio state, transmitting etc.
*
* @return Radio state
*/
nRF905_radio_state_t nRF905_getState(void);

/**
* Receive mode. If the radio is currently transmitting then receive mode will be entered once it has finished.
*
* @return (none)
*/
void nRF905_receive(void);

/**
* Get received payload if available.
*
* @param [data] Pointer to buffer to place data
* @param [len] How many bytes to copy
* @return false if no data available, otherwise true
*/
uint8_t nRF905_getData(uint8_t * data, uint8_t len);

/**
* Wake up into standby mode.
* Will take 3ms to complete.
*
* @return (none)
*/
void nRF905_powerUp(void);

/**
* Sleep.
*
* @note Must call nRF905_powerUp() before transmitting or receiving again.
* @return (none)
*/
void nRF905_powerDown(void);

/**
* Enter standby mode.
*
* @return (none)
*/
void nRF905_enterStandBy(void);

/**
* Leave standby and go into receive mode (same as just calling nRF905_receive()).
*
* @return (none)
*/
inline void nRF905_leaveStandBy(void)
{
	nRF905_receive();
}

/**
* blah
*
* @return blah
*/
bool nRF905_receiveBusy(void);

/**
* See if airway is busy (carrier detect pin high).
*
* @return true if other transmissions detected, otherwise false
*/
inline bool nRF905_airwayBusy(void)
{
	return digitalRead(CD);
}

/**
* Disable data ready interrupt.
*
* If NRF905_INTERRUPTS is enabled then this function must be called before doing SPI communications with any other device.
*
* @return (none)
*/
inline void nRF905_interrupt_off(void)
{
#if NRF905_INTERRUPTS
	REG_EXTERNAL_INT &= ~_BV(BIT_EXTERNAL_INT);
#endif
}

/**
* Enable data ready interrupt.
*
* If NRF905_INTERRUPTS is enabled then this function must be called once you have finished doing SPI communications with another device.
*
* @return (none)
*/
inline void nRF905_interrupt_on(void)
{
#if NRF905_INTERRUPTS
	REG_EXTERNAL_INT |= _BV(BIT_EXTERNAL_INT);
#endif
}

#endif /* NRF905_H_ */