/*
 * Copyright (c) 2012, Jonas Widén (jonas.widen@widens.eu)
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "nexa_new.h"

#include <stdint.h>
#include <unistd.h>
#include <wiringPi.h>

#define NEXA_DELAY_HIGH 250
#define NEXA_DELAY_ZERO 1250
#define NEXA_DELAY_ONE 250
#define NEXA_DELAY_SYNC 2500

#define NEXA_RESENDS 6

#define NEXA_CLASS_1 (0x5)
#define NEXA_CLASS_2 (0x6)
#define NEXA_CLASS_3 (0x9)
#define NEXA_CLASS_4 (0xa)

static void send_zero(void)
{
  digitalWrite(NEXA_PIN, HIGH);
  usleep(NEXA_DELAY_HIGH);
  digitalWrite(NEXA_PIN, LOW);
  usleep(NEXA_DELAY_ZERO);
}

static void send_one(void)
{
  digitalWrite(NEXA_PIN, HIGH);
  usleep(NEXA_DELAY_HIGH);
  digitalWrite(NEXA_PIN, LOW);
  usleep(NEXA_DELAY_ONE);
}

static void send_sync(void)
{
  digitalWrite(NEXA_PIN, HIGH);
  usleep(NEXA_DELAY_HIGH);
  digitalWrite(NEXA_PIN, LOW);
  usleep(NEXA_DELAY_SYNC);
}

static void send_nibble(uint8_t nibble)
{
  if (nibble & 0x08) send_one(); else send_zero();
  if (nibble & 0x04) send_one(); else send_zero();
  if (nibble & 0x02) send_one(); else send_zero();
  if (nibble & 0x01) send_one(); else send_zero();
}

static void send_id(void)
{
  uint8_t i;
  uint8_t id[7] = {0x96, 0xa5, 0x55, 0xa5, 0x55, 0x55, 0x6};
  for (i = 0; i < 7; ++i) {
    if (i < 6) {
      send_nibble((id[i] >> 4) & 0x0f);
    }
    send_nibble(id[i] & 0x0f);
  }
}

static void send_group(bool group_mode)
{
  if (group_mode) {
    send_zero();
    send_one();
  }
  else {
    send_one();
    send_zero();
  }
}

static void send_activation(nexa_activation_t mode)
{
  switch(mode) {
  case NEXA_ACTIVATION_OFF:
    send_one();
    send_zero();
    break;
  case NEXA_ACTIVATION_ON:
    send_zero();
    send_one();
    break;
  case NEXA_ACTIVATION_DIM:
    send_one();
    send_one();
    break;
  default:
    send_one();
    send_zero();
    break;
  }
}

static void send_dim_level(nexa_dim_level_t level)
{
  switch(level) {
  case NEXA_DIM_LEVEL_1:
    send_nibble(NEXA_CLASS_1);
    send_nibble(NEXA_CLASS_2);
    break;
  case NEXA_DIM_LEVEL_2:
    send_nibble(NEXA_CLASS_3);
    send_nibble(NEXA_CLASS_2);
    break;
  case NEXA_DIM_LEVEL_3:
    send_nibble(NEXA_CLASS_2);
    send_nibble(NEXA_CLASS_2);
    break;
  case NEXA_DIM_LEVEL_4:
    send_nibble(NEXA_CLASS_4);
    send_nibble(NEXA_CLASS_2);
    break;
  case NEXA_DIM_LEVEL_5:
    send_nibble(NEXA_CLASS_1);
    send_nibble(NEXA_CLASS_4);
    break;
  case NEXA_DIM_LEVEL_6:
    send_nibble(NEXA_CLASS_3);
    send_nibble(NEXA_CLASS_4);
    break;
  case NEXA_DIM_LEVEL_7:
    send_nibble(NEXA_CLASS_2);
    send_nibble(NEXA_CLASS_4);
    break;
  case NEXA_DIM_LEVEL_8:
    send_nibble(NEXA_CLASS_4);
    send_nibble(NEXA_CLASS_4);
    break;
  case NEXA_DIM_LEVEL_9:
    send_nibble(NEXA_CLASS_1);
    send_nibble(NEXA_CLASS_3);
    break;
  case NEXA_DIM_LEVEL_10:
    send_nibble(NEXA_CLASS_3);
    send_nibble(NEXA_CLASS_3);
    break;
  case NEXA_DIM_LEVEL_11:
    send_nibble(NEXA_CLASS_2);
    send_nibble(NEXA_CLASS_3);
    break;
  case NEXA_DIM_LEVEL_12:
    send_nibble(NEXA_CLASS_4);
    send_nibble(NEXA_CLASS_3);
    break;
  case NEXA_DIM_LEVEL_13:
    send_nibble(NEXA_CLASS_2);
    send_nibble(NEXA_CLASS_1);
    break;
  case NEXA_DIM_LEVEL_14:
    send_nibble(NEXA_CLASS_4);
    send_nibble(NEXA_CLASS_1);
    break;
  case NEXA_DIM_LEVEL_15:
    send_nibble(NEXA_CLASS_3);
    send_nibble(NEXA_CLASS_1);
    break;
  case NEXA_DIM_LEVEL_16:
    send_nibble(NEXA_CLASS_1);
    send_nibble(NEXA_CLASS_1);
    break;
  }
}

static void send_channel(nexa_channel_t channel)
{
  switch(channel) {
  case NEXA_CHANNEL_1:
    send_nibble(NEXA_CLASS_1);
    break;
  case NEXA_CHANNEL_2:
    send_nibble(NEXA_CLASS_2);
    break;
  case NEXA_CHANNEL_3:
    send_nibble(NEXA_CLASS_3);
    break;
  case NEXA_CHANNEL_4:
    send_nibble(NEXA_CLASS_4);
    break;
  default:
    send_nibble(NEXA_CLASS_1);
    break;
  }
}

static void send_button(nexa_button_t channel)
{
  switch(channel) {
  case NEXA_BUTTON_1:
    send_nibble(NEXA_CLASS_1);
    break;
  case NEXA_BUTTON_2:
    send_nibble(NEXA_CLASS_2);
    break;
  case NEXA_BUTTON_3:
    send_nibble(NEXA_CLASS_3);
    break;
  case NEXA_BUTTON_4:
    send_nibble(NEXA_CLASS_4);
    break;
  default:
    send_nibble(NEXA_CLASS_1);
    break;
  }
}

void nexa_new_init(void)
{
  wiringPiSetup();
  pinMode(NEXA_PIN, OUTPUT);
  digitalWrite(NEXA_PIN, LOW);
}

void nexa_new_transmit(nexa_channel_t channel,
                       nexa_button_t button,
                       nexa_activation_t activation,
                       nexa_dim_level_t level,
                       bool group_mode)
{
  uint8_t i;
  for (i = 0; i < NEXA_RESENDS; ++i) {
    send_sync();
    send_id();
    send_group(group_mode);
    send_activation(activation);
    send_channel(channel);
    send_button(button);
    if (activation == NEXA_ACTIVATION_DIM) {
      send_dim_level(level);
    }
    send_zero();
    usleep(10);
  }
}