/*
 * This file is part of the DSLogic-gui project.
 * DSLogic-gui is based on PulseView.
 *
 * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
 * Copyright (C) 2013 DreamSourceLab <dreamsourcelab@dreamsourcelab.com>
 *
 * 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 2 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, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */


#include <extdef.h>

#include <assert.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>

#include <algorithm>

#include <boost/foreach.hpp>

#include "logicsnapshot.h"
#include "groupsnapshot.h"

using namespace boost;
using namespace std;

namespace pv {
namespace data {

const int GroupSnapshot::EnvelopeScalePower = 4;
const int GroupSnapshot::EnvelopeScaleFactor = 1 << EnvelopeScalePower;
const float GroupSnapshot::LogEnvelopeScaleFactor =
	logf(EnvelopeScaleFactor);
const uint64_t GroupSnapshot::EnvelopeDataUnit = 64*1024;	// bytes
const uint16_t GroupSnapshot::value_mask[16] = {0x1, 0x2, 0x4, 0x8,
                                                0x10, 0x20, 0x40, 0x80,
                                                0x100, 0x200, 0x400, 0x800,
                                                0x1000, 0x2000, 0x4000, 0x8000};

GroupSnapshot::GroupSnapshot(const boost::shared_ptr<LogicSnapshot> &_logic_snapshot, std::list<int> index_list)
{
    assert(_logic_snapshot);

	boost::lock_guard<boost::recursive_mutex> lock(_mutex);
	memset(_envelope_levels, 0, sizeof(_envelope_levels));
    _data = _logic_snapshot->get_data();
    _sample_count = _logic_snapshot->get_sample_count();
    _unit_size = _logic_snapshot->get_unit_size();
    _index_list = index_list;
    append_payload();
}

GroupSnapshot::~GroupSnapshot()
{
	boost::lock_guard<boost::recursive_mutex> lock(_mutex);
	BOOST_FOREACH(Envelope &e, _envelope_levels)
		free(e.samples);
}

uint64_t GroupSnapshot::get_sample_count() const
{
    boost::lock_guard<boost::recursive_mutex> lock(_mutex);
    return _sample_count;
}

void GroupSnapshot::append_payload()
{
	boost::lock_guard<boost::recursive_mutex> lock(_mutex);

	// Generate the first mip-map from the data
	append_payload_to_envelope_levels();
}

const uint16_t* GroupSnapshot::get_samples(
    int64_t start_sample, int64_t end_sample)
{
	assert(start_sample >= 0);
	assert(start_sample < (int64_t)_sample_count);
	assert(end_sample >= 0);
	assert(end_sample < (int64_t)_sample_count);
	assert(start_sample <= end_sample);

    int64_t i;
    uint64_t pow;
	boost::lock_guard<boost::recursive_mutex> lock(_mutex);

    uint16_t *const data = new uint16_t[end_sample - start_sample];
//    memcpy(data, (uint16_t*)_data + start_sample, sizeof(uint16_t) *
//		(end_sample - start_sample));
    memset(data, 0, sizeof(uint16_t) * (end_sample - start_sample));
    for(i = start_sample; i < end_sample; i++) {
        std::list<int>::iterator j = _index_list.begin();
        pow = 0;
        while(j != _index_list.end()) {
            *(data + i - start_sample) += ((*((uint16_t*)_data + i) & value_mask[(*j)]) >> ((*j) - pow));
            pow++;
            j++;
        }
    }
	return data;
}

void GroupSnapshot::get_envelope_section(EnvelopeSection &s,
	uint64_t start, uint64_t end, float min_length) const
{
    assert(end <= _sample_count);
	assert(start <= end);
	assert(min_length > 0);

	boost::lock_guard<boost::recursive_mutex> lock(_mutex);

	const unsigned int min_level = max((int)floorf(logf(min_length) /
		LogEnvelopeScaleFactor) - 1, 0);
	const unsigned int scale_power = (min_level + 1) *
		EnvelopeScalePower;
	start >>= scale_power;
	end >>= scale_power;

	s.start = start << scale_power;
	s.scale = 1 << scale_power;
	s.length = end - start;
	s.samples = new EnvelopeSample[s.length];
	memcpy(s.samples, _envelope_levels[min_level].samples + start,
		s.length * sizeof(EnvelopeSample));
}

void GroupSnapshot::reallocate_envelope(Envelope &e)
{
	const uint64_t new_data_length = ((e.length + EnvelopeDataUnit - 1) /
		EnvelopeDataUnit) * EnvelopeDataUnit;
	if (new_data_length > e.data_length)
	{
		e.data_length = new_data_length;
		e.samples = (EnvelopeSample*)realloc(e.samples,
			new_data_length * sizeof(EnvelopeSample));
	}
}

void GroupSnapshot::append_payload_to_envelope_levels()
{
	Envelope &e0 = _envelope_levels[0];
	uint64_t prev_length;
	EnvelopeSample *dest_ptr;

	// Expand the data buffer to fit the new samples
	prev_length = e0.length;
	e0.length = _sample_count / EnvelopeScaleFactor;

	// Break off if there are no new samples to compute
	if (e0.length == prev_length)
		return;

	reallocate_envelope(e0);

	dest_ptr = e0.samples + prev_length;

	// Iterate through the samples to populate the first level mipmap
    uint16_t group_value[EnvelopeScaleFactor];
    const uint16_t *const end_src_ptr = (uint16_t*)_data +
        e0.length * EnvelopeScaleFactor;
    for (const uint16_t *src_ptr = (uint16_t*)_data +
		prev_length * EnvelopeScaleFactor;
		src_ptr < end_src_ptr; src_ptr += EnvelopeScaleFactor)
	{
        int pow;
//        for(i = 0; i < EnvelopeScaleFactor; i++) {
//            group_value[i] = 0;
//            std::list<int>::iterator j = _index_list.begin();
//            pow = 0;
//            while(j != _index_list.end()) {
//                group_value[i] += ((*(src_ptr + i) & value_mask[(*j)]) >> ((*j) - pow));
//                pow++;
//                j++;
//            }
//        }
        group_value[0] = 0;
        group_value[1] = 0;
        group_value[2] = 0;
        group_value[3] = 0;
        group_value[4] = 0;
        group_value[5] = 0;
        group_value[6] = 0;
        group_value[7] = 0;
        group_value[8] = 0;
        group_value[9] = 0;
        group_value[10] = 0;
        group_value[11] = 0;
        group_value[12] = 0;
        group_value[13] = 0;
        group_value[14] = 0;
        group_value[15] = 0;
        std::list<int>::iterator j = _index_list.begin();
        pow = 0;
        while(j != _index_list.end()) {
            group_value[0] += ((*(src_ptr + 0) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[1] += ((*(src_ptr + 1) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[2] += ((*(src_ptr + 2) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[3] += ((*(src_ptr + 3) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[4] += ((*(src_ptr + 4) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[5] += ((*(src_ptr + 5) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[6] += ((*(src_ptr + 6) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[7] += ((*(src_ptr + 7) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[8] += ((*(src_ptr + 8) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[9] += ((*(src_ptr + 9) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[10] += ((*(src_ptr + 10) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[11] += ((*(src_ptr + 11) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[12] += ((*(src_ptr + 12) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[13] += ((*(src_ptr + 13) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[14] += ((*(src_ptr + 14) & value_mask[(*j)]) >> ((*j) - pow));
            group_value[15] += ((*(src_ptr + 15) & value_mask[(*j)]) >> ((*j) - pow));
            pow++;
            j++;
        }
		const EnvelopeSample sub_sample = {
            *min_element(group_value, group_value + EnvelopeScaleFactor),
            *max_element(group_value, group_value + EnvelopeScaleFactor),
		};

		*dest_ptr++ = sub_sample;
	}

	// Compute higher level mipmaps
	for (unsigned int level = 1; level < ScaleStepCount; level++)
	{
		Envelope &e = _envelope_levels[level];
		const Envelope &el = _envelope_levels[level-1];

		// Expand the data buffer to fit the new samples
		prev_length = e.length;
		e.length = el.length / EnvelopeScaleFactor;

		// Break off if there are no more samples to computed
		if (e.length == prev_length)
			break;

		reallocate_envelope(e);

		// Subsample the level lower level
		const EnvelopeSample *src_ptr =
			el.samples + prev_length * EnvelopeScaleFactor;
		const EnvelopeSample *const end_dest_ptr = e.samples + e.length;
		for (dest_ptr = e.samples + prev_length;
			dest_ptr < end_dest_ptr; dest_ptr++)
		{
			const EnvelopeSample *const end_src_ptr =
				src_ptr + EnvelopeScaleFactor;

			EnvelopeSample sub_sample = *src_ptr++;
			while (src_ptr < end_src_ptr)
			{
				sub_sample.min = min(sub_sample.min, src_ptr->min);
				sub_sample.max = max(sub_sample.max, src_ptr->max);
				src_ptr++;
			}

			*dest_ptr = sub_sample;
		}
	}
}

} // namespace data
} // namespace pv