/*
 * Copyright (C) 2020 Linux Studio Plugins Project <https://lsp-plug.in/>
 *           (C) 2020 Vladimir Sadovnikov <sadko4u@gmail.com>
 *
 * This file is part of lsp-plugins
 * Created on: 20 мая 2016 г.
 *
 * lsp-plugins is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * any later version.
 *
 * lsp-plugins 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with lsp-plugins. If not, see <https://www.gnu.org/licenses/>.
 */

#include <lsp-plug.in/dsp-units/util/MeterGraph.h>
#include <lsp-plug.in/dsp/dsp.h>

namespace lsp
{
    namespace dspu
    {
        MeterGraph::MeterGraph()
        {
            construct();
        }

        MeterGraph::~MeterGraph()
        {
            destroy();
        }

        void MeterGraph::construct()
        {
            sBuffer.construct();

            fCurrent    = 0.0f;
            nCount      = 0;
            nPeriod     = 1;
            bMinimize   = false;
        }

        void MeterGraph::destroy()
        {
            sBuffer.destroy();
        }

        bool MeterGraph::init(size_t frames, size_t period)
        {
            if (period <= 0)
                return false;

            if (!sBuffer.init(frames * 4, frames))
                return false;

            fCurrent    = 0.0f;
            nCount      = 0;
            nPeriod     = period;
            return true;
        }

        void MeterGraph::process(float sample)
        {
            // Make sample positive
            if (sample < 0)
                sample      = - sample;

            if (bMinimize)
            {
                // Update current sample
                if (nCount == 0)
                    fCurrent    = sample;
                else if (fCurrent < sample)
                    fCurrent    = sample;
            }
            else
            {
                // Update current sample
                if (nCount == 0)
                    fCurrent    = sample;
                else if (fCurrent > sample)
                    fCurrent    = sample;
            }

            // Increment number of samples processed
            if ((++nCount) >= nPeriod)
            {
                // Append current sample to buffer
                sBuffer.shift();
                sBuffer.append(fCurrent);

                // Update counter
                nCount      = 0;
            }
        }

        void MeterGraph::process(const float *s, size_t n)
        {
            if (bMinimize)
            {
                while (n > 0)
                {
                    // Determine amount of samples to process
                    ssize_t can_do      = nPeriod - nCount;
                    if (can_do > ssize_t(n))
                        can_do          = n;

                    // Process the samples
                    if (can_do > 0)
                    {
                        // Get maximum sample
                        float sample        = dsp::abs_min(s, can_do);
                        if (nCount == 0)
                            fCurrent        = sample;
                        else if (fCurrent > sample)
                            fCurrent        = sample;

                        // Update counters and pointers
                        nCount             += can_do;
                        n                  -= can_do;
                        s                  += can_do;
                    }

                    // Check that need to switch to next sample
                    if (nCount >= nPeriod)
                    {
                        // Append current sample to buffer
                        sBuffer.shift();
                        sBuffer.append(fCurrent);

                        // Update counter
                        nCount      = 0;
                    }
                }
            }
            else
            {
                while (n > 0)
                {
                    // Determine amount of samples to process
                    ssize_t can_do      = nPeriod - nCount;
                    if (can_do > ssize_t(n))
                        can_do          = n;

                    // Process the samples
                    if (can_do > 0)
                    {
                        // Get maximum sample
                        float sample        = dsp::abs_max(s, can_do);
                        if (nCount == 0)
                            fCurrent        = sample;
                        else if (fCurrent < sample)
                            fCurrent        = sample;

                        // Update counters and pointers
                        nCount             += can_do;
                        n                  -= can_do;
                        s                  += can_do;
                    }

                    // Check that need to switch to next sample
                    if (nCount >= nPeriod)
                    {
                        // Append current sample to buffer
                        sBuffer.shift();
                        sBuffer.append(fCurrent);

                        // Update counter
                        nCount      = 0;
                    }
                }
            }
        }

        void MeterGraph::dump(IStateDumper *v) const
        {
            v->write_object("sBuffer", &sBuffer);
            v->write("fCurrent", fCurrent);
            v->write("nCount", nCount);
            v->write("nPeriod", nPeriod);
            v->write("bMinimize", bMinimize);
        }
    }
}



