/***************************************************************************
 *   Copyright (C) 02/2021 by Olaf Rempel                                  *
 *   razzor@kopf-tisch.de                                                  *
 *                                                                         *
 *   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; version 2 of the License,               *
 *                                                                         *
 *   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, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

#include <avr/pgmspace.h>

#include "event.h"
#include "ledfade.h"
#include "timer.h"

/* *********************************************************************** */

#define LEDFADE_CHANNEL_COUNT   2
#define LEDFADE_FULL_FADE_MS    1000
#define LEDFADE_16BIT           1

#if (LEDFADE_16BIT)
#define LEDFADE_TABLE_SIZE      128
#define LEDFADE_TABLE_GET(x)    pgm_read_word(&m_ledfade_table16[x])
const uint16_t m_ledfade_table16[LEDFADE_TABLE_SIZE] PROGMEM =
{
    0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4, 5, 5,
    6, 6, 7, 8, 9, 9, 10, 11, 12, 14, 15, 16, 18, 20, 22, 24, 26,
    28, 31, 34, 37, 40, 44, 48, 53, 58, 63, 69, 75, 82, 90, 98,
    107, 116, 127, 139, 151, 165, 180, 196, 214, 234, 255, 278,
    303, 331, 361, 394, 430, 469, 511, 557, 608, 663, 723, 789,
    860, 938, 1023, 1116, 1217, 1327, 1447, 1578, 1721, 1877,
    2047, 2232, 2434, 2655, 2895, 3157, 3443, 3755, 4095, 4466,
    4870, 5311, 5792, 6316, 6888, 7511, 8191, 8932, 9741, 10623,
    11584, 12633, 13776, 15023, 16383, 17866, 19483, 21246, 23169,
    25267, 27553, 30047, 32767, 35733, 38967, 42494, 46340, 50534,
    55108, 60096, 65535
};
#else
#define LEDFADE_TABLE_SIZE      32
#define LEDFADE_TABLE_GET(x)    pgm_read_byte(&m_ledfade_table8[x])
const uint8_t m_ledfade_table8[LEDFADE_TABLE_SIZE] PROGMEM =
{
    0, 0, 1, 1, 1, 2, 2, 3,
    4, 5, 6, 7, 9, 10, 12, 15,
    18, 22, 26, 31, 37, 44, 53, 63,
    75, 90, 107, 127, 151, 180, 214, 255
};
#endif

#define LEDFADE_FADE_STEP_MS ((LEDFADE_FULL_FADE_MS + LEDFADE_TABLE_SIZE) / LEDFADE_TABLE_SIZE)

static uint8_t m_ledfade_value[LEDFADE_CHANNEL_COUNT];
static uint8_t m_ledfade_setpoint[LEDFADE_CHANNEL_COUNT];
static uint8_t m_ledfade_setpoint_save[LEDFADE_CHANNEL_COUNT];
static uint8_t m_ledfade_timer_running;

/* *********************************************************************** */

static void ledfade_update(uint8_t channel, uint8_t force_event)
{
    uint8_t update_pwm = 0;

    if (m_ledfade_setpoint[channel] >= LEDFADE_TABLE_SIZE)
    {
        m_ledfade_setpoint[channel] = (LEDFADE_TABLE_SIZE -1);
    }

    if ((m_ledfade_setpoint[channel] > m_ledfade_value[channel]) &&
        (m_ledfade_value[channel] < (LEDFADE_TABLE_SIZE -1))
       )
    {
        m_ledfade_value[channel]++;
        update_pwm = 1;
    }
    else if ((m_ledfade_setpoint[channel] < m_ledfade_value[channel]) &&
             (m_ledfade_value[channel] > 0)
            )
    {
        m_ledfade_value[channel]--;
        update_pwm = 1;
    }

    if (update_pwm || force_event)
    {
        event_queue(EVENT_TYPE_PWM_VALUE,
                    channel,
                    LEDFADE_TABLE_GET(m_ledfade_value[channel]));

        if (m_ledfade_value[channel] == m_ledfade_setpoint[channel])
        {
            event_queue(EVENT_TYPE_LEDFADE_STATUS,
                        channel,
                        m_ledfade_value[channel]);
        }
        else if (!m_ledfade_timer_running)
        {
            event_queue(EVENT_TYPE_TIMER_SET,
                        EVENT_NUM_TIMER_LEDFADE,
                        LEDFADE_FADE_STEP_MS);

            m_ledfade_timer_running = 1;
        }
    }
} /* ledfade_update */


void ledfade_event_handler(event_entry_t * p_event)
{
    if (p_event->type == EVENT_TYPE_LEDFADE_COMMAND)
    {
        uint8_t channel = p_event->num;

        switch (p_event->value)
        {
        case EVENT_VALUE_LEDFADE_KEEP:
            m_ledfade_setpoint[channel] = m_ledfade_value[channel];
            break;

        /* increment */
        case EVENT_VALUE_LEDFADE_INC:
            if (m_ledfade_setpoint[channel] < (LEDFADE_TABLE_SIZE -1))
            {
                m_ledfade_setpoint[channel]++;
            }
            break;

        /* decrement */
        case EVENT_VALUE_LEDFADE_DEC:
            if (m_ledfade_setpoint[channel] > 0)
            {
                m_ledfade_setpoint[channel]--;
            }
            break;

        /* fade to min */
        case EVENT_VALUE_LEDFADE_MIN:
            m_ledfade_setpoint[channel] = 0;
            break;

        /* fade to max */
        case EVENT_VALUE_LEDFADE_MAX:
            m_ledfade_setpoint[channel] = (LEDFADE_TABLE_SIZE -1);
            break;

        /* toggle between 0 and stored value */
        case EVENT_VALUE_LEDFADE_TOGGLE:
            if (m_ledfade_setpoint[channel] > 5)
            {
                m_ledfade_setpoint_save[channel] = m_ledfade_setpoint[channel];
                m_ledfade_setpoint[channel] = 0;
            }
            else
            {
                m_ledfade_setpoint[channel] = m_ledfade_setpoint_save[channel];
            }
            break;

        default:
            break;
        }

        ledfade_update(channel, 1);
    }
    else if (p_event->type == EVENT_TYPE_LEDFADE_VALUE)
    {
        uint8_t channel = p_event->num;

        if (p_event->value < LEDFADE_TABLE_SIZE)
        {
            m_ledfade_setpoint[channel] = p_event->value;
        }
        else
        {
            m_ledfade_setpoint[channel] = (LEDFADE_TABLE_SIZE -1);
        }

        ledfade_update(channel, 1);
    }
    else if ((p_event->type == EVENT_TYPE_TIMER_ELAPSED) &&
             (p_event->num == EVENT_NUM_TIMER_LEDFADE)
            )
    {
        m_ledfade_timer_running = 0;

        ledfade_update(0, 0);
        ledfade_update(1, 0);
    }
} /* ledfade_event_handler */