/**
 * Marlin 3D Printer Firmware
 * Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
 * Based on Sprinter and grbl.
 * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef _HAL_SERIAL_H_
#define _HAL_SERIAL_H_

#include <stdarg.h>
#include <stdio.h>

extern "C" {
#include <debug_frmwrk.h>
}

/**
 * Generic RingBuffer
 * T type of the buffer array
 * S size of the buffer (must be power of 2)
 *
 * todo: optimise
 */
template <typename T, uint32_t S> class RingBuffer {
public:
  RingBuffer() { index_read = index_write = 0; }
  uint32_t available() volatile { return buffer_mask & (index_write - index_read); }
  uint32_t free() volatile      { return buffer_size - available(); }
  bool empty() volatile         { return (buffer_mask & index_read) == (buffer_mask & index_write); }
  bool full() volatile          { return index_read == buffer_mask & (index_write + 1); }
  void clear() volatile         { index_read = index_write = 0; }
  bool peek(T *value) volatile {
    if (value == 0 || available() == 0)
      return false;
    *value = buffer[buffer_mask & index_read];
    return true;
  }
  int read() volatile {
    if ((buffer_mask & index_read) == (buffer_mask & index_write)) return -1;
    T val = buffer[buffer_mask & index_read];
    ++index_read;
    return val;
  }
  bool write(T value) volatile {
    uint32_t next_head = buffer_mask & (index_write + 1);
    if (next_head != index_read) {
      buffer[buffer_mask & index_write] = value;
      index_write = next_head;
      return true;
    }
    return false;
  }

private:
  static const uint32_t buffer_size = S;
  static const uint32_t buffer_mask = buffer_size - 1;
  volatile T buffer[buffer_size];
  volatile uint32_t index_write;
  volatile uint32_t index_read;
};

class HalSerial {
public:
  HalSerial() { host_connected = false; }

  void begin(int32_t baud) {
  }

  int peek() {
    uint8_t value;
    return receive_buffer.peek(&value) ? value : -1;
  }

  int read() { return receive_buffer.read(); }

  size_t write(char c) { return host_connected ? transmit_buffer.write((uint8_t)c) : 0; }

  operator bool() { return host_connected; }

  uint16_t available() {
    return (uint16_t)receive_buffer.available();
  }

  void flush() { receive_buffer.clear(); }

  uint8_t availableForWrite(void){
    return transmit_buffer.free() > 255 ? 255 : (uint8_t)transmit_buffer.free();
  }

  void flushTX(void){
    if (host_connected)
      while (transmit_buffer.available()) { /* nada */ }
  }

  void printf(const char *format, ...) {
    static char buffer[256];
    va_list vArgs;
    va_start(vArgs, format);
    int length = vsnprintf((char *) buffer, 256, (char const *) format, vArgs);
    va_end(vArgs);
    if (length > 0 && length < 256) {
      if (host_connected) {
        for (int i = 0; i < length;) {
          if (transmit_buffer.write(buffer[i])) {
            ++i;
          }
        }
      }
    }
  }

  #define DEC 10
  #define HEX 16
  #define OCT 8
  #define BIN 2

  void print_bin(uint32_t value, uint8_t num_digits) {
    uint32_t mask = 1 << (num_digits -1);
    for (uint8_t i = 0; i < num_digits; i++) {
      if (!(i % 4) && i)    write(' ');
      if (!(i % 16)  && i)  write(' ');
      if (value & mask)     write('1');
      else                  write('0');
      value <<= 1;
    }
  }

  void print(const char value[]) { printf("%s" , value); }
  void print(char value, int nbase = 0) {
    if (nbase == BIN) print_bin(value, 8);
    else if (nbase == OCT) printf("%3o", value);
    else if (nbase == HEX) printf("%2X", value);
    else if (nbase == DEC ) printf("%d", value);
    else printf("%c" , value);
  }
  void print(unsigned char value, int nbase = 0) {
    if (nbase == BIN) print_bin(value, 8);
    else if (nbase == OCT) printf("%3o", value);
    else if (nbase == HEX) printf("%2X", value);
    else printf("%u" , value);
  }
  void print(int value, int nbase = 0) {
    if (nbase == BIN) print_bin(value, 16);
    else if (nbase == OCT) printf("%6o", value);
    else if (nbase == HEX) printf("%4X", value);
    else printf("%d", value);
  }
  void print(unsigned int value, int nbase = 0) {
    if (nbase == BIN) print_bin(value, 16);
    else if (nbase == OCT) printf("%6o", value);
    else if (nbase == HEX) printf("%4X", value);
    else printf("%u" , value);
  }
  void print(long value, int nbase = 0) {
    if (nbase == BIN) print_bin(value, 32);
    else if (nbase == OCT) printf("%11o", value);
    else if (nbase == HEX) printf("%8X", value);
    else printf("%ld" , value);
  }
  void print(unsigned long value, int nbase = 0) {
    if (nbase == BIN) print_bin(value, 32);
    else if (nbase == OCT) printf("%11o", value);
    else if (nbase == HEX) printf("%8X", value);
    else printf("%lu" , value);
  }
  void print(float value, int round = 6)  { printf("%f" , value); }
  void print(double value, int round = 6) { printf("%f" , value); }

  void println(const char value[]) { printf("%s\n" , value); }
  void println(char value, int nbase = 0) { print(value, nbase); println(); }
  void println(unsigned char value, int nbase = 0) { print(value, nbase); println(); }
  void println(int value, int nbase = 0) { print(value, nbase); println(); }
  void println(unsigned int value, int nbase = 0) { print(value, nbase); println(); }
  void println(long value, int nbase = 0) { print(value, nbase); println(); }
  void println(unsigned long value, int nbase = 0) { print(value, nbase); println(); }
  void println(float value, int round = 6) { printf("%f\n" , value); }
  void println(double value, int round = 6) { printf("%f\n" , value); }
  void println(void) { print('\n'); }

  volatile RingBuffer<uint8_t, 128> receive_buffer;
  volatile RingBuffer<uint8_t, 128> transmit_buffer;
  volatile bool host_connected;
};

#endif // _HAL_SERIAL_H_