/*
  CapacitiveSense.h v.04 - Capacitive Sensing Library for 'duino / Wiring
  https://github.com/PaulStoffregen/CapacitiveSensor
  http://www.pjrc.com/teensy/td_libs_CapacitiveSensor.html
  http://playground.arduino.cc/Main/CapacitiveSensor
  Copyright (c) 2008 Paul Bagder  All rights reserved.
  Version 05 by Paul Stoffregen - Support non-AVR board: Teensy 3.x, Arduino Due
  Version 04 by Paul Stoffregen - Arduino 1.0 compatibility, issue 146 fix
  vim: set ts=4:
*/

// ensure this library description is only included once
#ifndef CapacitiveSensor_h
#define CapacitiveSensor_h

#if ARDUINO >= 100
#include "Arduino.h"
#else
#include "WProgram.h"
#endif

// Direct I/O through registers and bitmask (from OneWire library)

#if defined(__AVR__)
#define PIN_TO_BASEREG(pin)             (portInputRegister(digitalPinToPort(pin)))
#define PIN_TO_BITMASK(pin)             (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint8_t
#define DIRECT_READ(base, mask)         (((*(base)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask)   ((*((base)+1)) &= ~(mask), (*((base)+2)) &= ~(mask))
#define DIRECT_MODE_OUTPUT(base, mask)  ((*((base)+1)) |= (mask))
#define DIRECT_WRITE_LOW(base, mask)    ((*((base)+2)) &= ~(mask))
#define DIRECT_WRITE_HIGH(base, mask)   ((*((base)+2)) |= (mask))

#elif defined(__MK20DX128__) || defined(__MK20DX256__) || defined(__MK66FX1M0__) || defined(__MK64FX512__)
#define PIN_TO_BASEREG(pin)             (portOutputRegister(pin))
#define PIN_TO_BITMASK(pin)             (1)
#define IO_REG_TYPE uint8_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask)         (*((base)+512))
#define DIRECT_MODE_INPUT(base, mask)   (*((base)+640) = 0)
#define DIRECT_MODE_OUTPUT(base, mask)  (*((base)+640) = 1)
#define DIRECT_WRITE_LOW(base, mask)    (*((base)+256) = 1)
#define DIRECT_WRITE_HIGH(base, mask)   (*((base)+128) = 1)

#elif defined(__MKL26Z64__)
#define PIN_TO_BASEREG(pin)             (portOutputRegister(pin))
#define PIN_TO_BITMASK(pin)             (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint8_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask)         ((*((base)+16) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask)   (*((base)+20) &= ~(mask))
#define DIRECT_MODE_OUTPUT(base, mask)  (*((base)+20) |= (mask))
#define DIRECT_WRITE_LOW(base, mask)    (*((base)+8) = (mask))
#define DIRECT_WRITE_HIGH(base, mask)   (*((base)+4) = (mask))

#elif defined(__SAM3X8E__)
#define PIN_TO_BASEREG(pin)             (&(digitalPinToPort(pin)->PIO_PER))
#define PIN_TO_BITMASK(pin)             (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask)         (((*((base)+15)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask)   ((*((base)+5)) = (mask))
#define DIRECT_MODE_OUTPUT(base, mask)  ((*((base)+4)) = (mask))
#define DIRECT_WRITE_LOW(base, mask)    ((*((base)+13)) = (mask))
#define DIRECT_WRITE_HIGH(base, mask)   ((*((base)+12)) = (mask))

#elif defined(__PIC32MX__)
#define PIN_TO_BASEREG(pin)             (portModeRegister(digitalPinToPort(pin)))
#define PIN_TO_BITMASK(pin)             (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask)         (((*(base+4)) & (mask)) ? 1 : 0)  //PORTX + 0x10
#define DIRECT_MODE_INPUT(base, mask)   ((*(base+2)) = (mask))            //TRISXSET + 0x08
#define DIRECT_MODE_OUTPUT(base, mask)  ((*(base+1)) = (mask))            //TRISXCLR + 0x04
#define DIRECT_WRITE_LOW(base, mask)    ((*(base+8+1)) = (mask))          //LATXCLR  + 0x24
#define DIRECT_WRITE_HIGH(base, mask)   ((*(base+8+2)) = (mask))          //LATXSET + 0x28

#elif defined(ARDUINO_ARCH_ESP8266)
#define PIN_TO_BASEREG(pin)             (portOutputRegister(digitalPinToPort(pin)))
#define PIN_TO_BITMASK(pin)             (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask)         (((*(base+6)) & (mask)) ? 1 : 0)    //GPIO_IN_ADDRESS
#define DIRECT_MODE_INPUT(base, mask)   ((*(base+5)) = (mask))              //GPIO_ENABLE_W1TC_ADDRESS
#define DIRECT_MODE_OUTPUT(base, mask)  ((*(base+4)) = (mask))              //GPIO_ENABLE_W1TS_ADDRESS
#define DIRECT_WRITE_LOW(base, mask)    ((*(base+2)) = (mask))              //GPIO_OUT_W1TC_ADDRESS
#define DIRECT_WRITE_HIGH(base, mask)   ((*(base+1)) = (mask))              //GPIO_OUT_W1TS_ADDRESS

#elif defined(__SAMD21G18A__)
// runs extremely slow/unreliable on Arduino Zero - help wanted....
#define PIN_TO_BASEREG(pin)             portModeRegister(digitalPinToPort(pin))
#define PIN_TO_BITMASK(pin)             (digitalPinToBitMask(pin))
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, mask)         (((*((base)+8)) & (mask)) ? 1 : 0)
#define DIRECT_MODE_INPUT(base, mask)   ((*((base)+1)) = (mask))
#define DIRECT_MODE_OUTPUT(base, mask)  ((*((base)+2)) = (mask))
#define DIRECT_WRITE_LOW(base, mask)    ((*((base)+5)) = (mask))
#define DIRECT_WRITE_HIGH(base, mask)   ((*((base)+6)) = (mask))

#elif defined(RBL_NRF51822)
#define PIN_TO_BASEREG(pin)             (0)
#define PIN_TO_BITMASK(pin)             (pin)
#define IO_REG_TYPE uint32_t
#define IO_REG_ASM
#define DIRECT_READ(base, pin)          nrf_gpio_pin_read(pin)
#define DIRECT_WRITE_LOW(base, pin)     nrf_gpio_pin_clear(pin)
#define DIRECT_WRITE_HIGH(base, pin)    nrf_gpio_pin_set(pin)
#define DIRECT_MODE_INPUT(base, pin)    nrf_gpio_cfg_input(pin, NRF_GPIO_PIN_NOPULL)
#define DIRECT_MODE_OUTPUT(base, pin)   nrf_gpio_cfg_output(pin)

#elif defined(__arc__)

#include "scss_registers.h"
#include "portable.h"
#include "avr/pgmspace.h"

#define GPIO_ID(pin)			(g_APinDescription[pin].ulGPIOId)
#define GPIO_TYPE(pin)			(g_APinDescription[pin].ulGPIOType)
#define GPIO_BASE(pin)			(g_APinDescription[pin].ulGPIOBase)
#define DIR_OFFSET_SS			0x01
#define DIR_OFFSET_SOC			0x04
#define EXT_PORT_OFFSET_SS		0x0A
#define EXT_PORT_OFFSET_SOC		0x50

/* GPIO registers base address */
#define PIN_TO_BASEREG(pin)		((volatile uint32_t *)g_APinDescription[pin].ulGPIOBase)
#define PIN_TO_BITMASK(pin)		pin
#define IO_REG_TYPE				uint32_t
#define IO_REG_ASM

static inline __attribute__((always_inline))
IO_REG_TYPE directRead(volatile IO_REG_TYPE *base, IO_REG_TYPE pin)
{
    IO_REG_TYPE ret;
    if (SS_GPIO == GPIO_TYPE(pin)) {
        ret = READ_ARC_REG(((IO_REG_TYPE)base + EXT_PORT_OFFSET_SS));
    } else {
        ret = MMIO_REG_VAL_FROM_BASE((IO_REG_TYPE)base, EXT_PORT_OFFSET_SOC);
    }
    return ((ret >> GPIO_ID(pin)) & 0x01);
}

static inline __attribute__((always_inline))
void directModeInput(volatile IO_REG_TYPE *base, IO_REG_TYPE pin)
{
    if (SS_GPIO == GPIO_TYPE(pin)) {
        WRITE_ARC_REG(READ_ARC_REG((((IO_REG_TYPE)base) + DIR_OFFSET_SS)) & ~(0x01 << GPIO_ID(pin)),
			((IO_REG_TYPE)(base) + DIR_OFFSET_SS));
    } else {
        MMIO_REG_VAL_FROM_BASE((IO_REG_TYPE)base, DIR_OFFSET_SOC) &= ~(0x01 << GPIO_ID(pin));
    }
}

static inline __attribute__((always_inline))
void directModeOutput(volatile IO_REG_TYPE *base, IO_REG_TYPE pin)
{
    if (SS_GPIO == GPIO_TYPE(pin)) {
        WRITE_ARC_REG(READ_ARC_REG(((IO_REG_TYPE)(base) + DIR_OFFSET_SS)) | (0x01 << GPIO_ID(pin)),
			((IO_REG_TYPE)(base) + DIR_OFFSET_SS));
    } else {
        MMIO_REG_VAL_FROM_BASE((IO_REG_TYPE)base, DIR_OFFSET_SOC) |= (0x01 << GPIO_ID(pin));
    }
}

static inline __attribute__((always_inline))
void directWriteLow(volatile IO_REG_TYPE *base, IO_REG_TYPE pin)
{
    if (SS_GPIO == GPIO_TYPE(pin)) {
        WRITE_ARC_REG(READ_ARC_REG(base) & ~(0x01 << GPIO_ID(pin)), base);
    } else {
        MMIO_REG_VAL(base) &= ~(0x01 << GPIO_ID(pin));
    }
}

static inline __attribute__((always_inline))
void directWriteHigh(volatile IO_REG_TYPE *base, IO_REG_TYPE pin)
{
    if (SS_GPIO == GPIO_TYPE(pin)) {
        WRITE_ARC_REG(READ_ARC_REG(base) | (0x01 << GPIO_ID(pin)), base);
    } else {
        MMIO_REG_VAL(base) |= (0x01 << GPIO_ID(pin));
    }
}

#define DIRECT_READ(base, pin)		directRead(base, pin)
#define DIRECT_MODE_INPUT(base, pin)	directModeInput(base, pin)
#define DIRECT_MODE_OUTPUT(base, pin)	directModeOutput(base, pin)
#define DIRECT_WRITE_LOW(base, pin)	directWriteLow(base, pin)
#define DIRECT_WRITE_HIGH(base, pin)	directWriteHigh(base, pin)

#endif

// some 3.3V chips with 5V tolerant pins need this workaround
//
#if defined(__MK20DX256__)
#define FIVE_VOLT_TOLERANCE_WORKAROUND
#endif

// library interface description
class CapacitiveSensor
{
  // user-accessible "public" interface
  public:
  // methods
	CapacitiveSensor(uint8_t sendPin, uint8_t receivePin);
	long capacitiveSensorRaw(uint8_t samples);
	long capacitiveSensor(uint8_t samples);
	void set_CS_Timeout_Millis(unsigned long timeout_millis);
	void reset_CS_AutoCal();
	void set_CS_AutocaL_Millis(unsigned long autoCal_millis);
  // library-accessible "private" interface
  private:
  // variables
	int error;
	unsigned long  leastTotal;
	unsigned int   loopTimingFactor;
	unsigned long  CS_Timeout_Millis;
	unsigned long  CS_AutocaL_Millis;
	unsigned long  lastCal;
	unsigned long  total;
	IO_REG_TYPE sBit;   // send pin's ports and bitmask
	volatile IO_REG_TYPE *sReg;
	IO_REG_TYPE rBit;    // receive pin's ports and bitmask
	volatile IO_REG_TYPE *rReg;
  // methods
	int SenseOneCycle(void);
};

#endif
