beamgrid/Source/AnalyserComponent.h

#pragma once

#include "JuceHeader.h"
#include "Analyser.h"
#include "BeamgridLookAndFeel.h"

// Black spectrum visualizer: teal analyzer bands and peak-colored markers.
class AnalyserComponent : public juce::Component,
                          public juce::Timer
{
public:
    enum { ModeBars = 1, ModeWaveform = 2, ModeLED = 3 };

    AnalyserComponent (Analyser& analyserToUse,
                       juce::AudioProcessorValueTreeState& paramsToUse,
                       BeamgridLookAndFeel& lookAndFeelToUse)
        : analyser (analyserToUse), params (paramsToUse), lf (lookAndFeelToUse)
    {
        startTimerHz (60);
    }

    ~AnalyserComponent() override
    {
        stopTimer();
    }

    void timerCallback() override
    {
        const double graceMs  = *params.getRawParameterValue ("grace");
        const double falloff  = *params.getRawParameterValue ("falloff");
        const double barfall  = *params.getRawParameterValue ("barfalloff");
        const int    bars     = juce::roundToInt (params.getRawParameterValue ("bars")->load());
        const double hue      = *params.getRawParameterValue ("hue");
        const int    mode     = juce::roundToInt (params.getRawParameterValue ("mode")->load());
        const int    leds     = juce::roundToInt (params.getRawParameterValue ("leds")->load());
        const double smooth   = *params.getRawParameterValue ("smooth");

        analyser.setGraceSeconds (graceMs / 1000.0);
        analyser.setFalloffRate (0.1 + falloff * 5.0);
        // Bar falloff: higher knob -> faster bar descent (smaller release tau).
        analyser.setBarReleaseTau (2.0 - barfall * 1.98);
        analyser.setNumBands (bars);

        // HUE knob: 12 o'clock (0.5) = no rotation; left/right rotate +/- 180 deg.
        lf.setHueTurns (static_cast<float> (hue - 0.5));

        displayMode  = mode;
        ledCount     = leds;
        smoothAmount = static_cast<float> (smooth);

        analyser.update (1.0 / 60.0);
        repaint();
    }

    void paint (juce::Graphics& g) override
    {
        const auto area = getLocalBounds().toFloat().reduced (8.0f);
        const int n = analyser.getNumBands();

        // Reserve margins for the axis legends.
        juce::Rectangle<float> plot = area;
        plot.setLeft (area.getX() + 40.0f);
        plot.setBottom (area.getBottom() - 20.0f);

        const float gap = 2.0f;
        const float bandWidth = (plot.getWidth() - gap * (n + 1)) / static_cast<float> (n);
        const float baseY = plot.getBottom();

        const juce::Colour gridColour  = lf.transform (juce::Colours::grey.brighter (0.2f)).withAlpha (0.32f);
        const juce::Colour labelColour = lf.transform (juce::Colours::grey);

        // --- Gridlines (drawn first; labels drawn last so they stay readable) ---
        const double freqTicks[] = { 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000, 20000 };
        for (double f : freqTicks)
        {
            if (f < analyser.getMinFreq() || f > analyser.getMaxFreq())
                continue;

            const float frac = analyser.freqToFraction (f);
            const float x = plot.getX() + gap + frac * (plot.getWidth() - 2.0f * gap);
            g.setColour (gridColour);
            g.drawVerticalLine (static_cast<int> (x), plot.getY(), plot.getBottom());
        }

        const double dbTicks[] = { 0.0, -6.0, -12.0, -24.0, -36.0, -48.0 };
        for (double db : dbTicks)
        {
            const float frac = analyser.dbToFraction (db);
            const float y = baseY - frac * plot.getHeight();
            g.setColour (gridColour);
            g.drawHorizontalLine (static_cast<int> (y), plot.getX(), plot.getRight());
        }

        // --- Spectrum content (mode dependent) ---
        if (displayMode == ModeWaveform)
            drawWaveform (g, n, plot, gap, bandWidth, baseY, smoothAmount);
        else if (displayMode == ModeLED)
            drawLED (g, n, plot, gap, bandWidth, baseY);
        else
            drawBars (g, n, plot, gap, bandWidth, baseY);

        // --- Axis labels (on top of everything) ---
        g.setFont (juce::FontOptions (10.0f));
        g.setColour (labelColour);
        for (double f : freqTicks)
        {
            if (f < analyser.getMinFreq() || f > analyser.getMaxFreq())
                continue;

            const float frac = analyser.freqToFraction (f);
            const float x = plot.getX() + gap + frac * (plot.getWidth() - 2.0f * gap);
            g.drawText (formatFreq (f), x - 18.0f, plot.getBottom() + 3.0f, 36.0f, 14.0f,
                        juce::Justification::centredTop, false);
        }

        for (double db : dbTicks)
        {
            const float frac = analyser.dbToFraction (db);
            const float y = baseY - frac * plot.getHeight();
            g.drawText (juce::String (db, 0), area.getX(), y - 7.0f, 36.0f, 14.0f,
                        juce::Justification::centredRight, false);
        }
    }

    static juce::String formatFreq (double f)
    {
        if (f >= 1000.0)
            return juce::String (f / 1000.0, 1, false) + "k";
        return juce::String (static_cast<int> (f));
    }

private:
    void drawBars (juce::Graphics& g, int n, const juce::Rectangle<float>& plot,
                   float gap, float bandWidth, float baseY)
    {
        for (int i = 0; i < n; ++i)
        {
            const float level = analyser.getLevel (i);
            const float peak  = analyser.getPeak (i);

            const float x = plot.getX() + gap + i * (bandWidth + gap);
            const float h = level * plot.getHeight();
            const float y = baseY - h;

            g.setColour (lf.getTeal());
            g.fillRect (x, y, bandWidth, h);

            const float peakY = baseY - peak * plot.getHeight();
            g.setColour (lf.getPeak());
            g.fillRect (x, peakY - 2.0f, bandWidth, 3.0f);
        }
    }

    void drawWaveform (juce::Graphics& g, int n, const juce::Rectangle<float>& plot,
                       float gap, float bandWidth, float baseY, float smooth)
    {
        // Gather the band levels and apply 1-2-1 smoothing passes. `smooth`
        // (0..1) blends each pass toward the averaged value, so 0 = untouched
        // (edgy/spiky) and 1 = heavily smoothed.
        const float t = juce::jlimit (0.0f, 1.0f, smooth);

        juce::HeapBlock<float> levels (static_cast<size_t> (n));
        for (int i = 0; i < n; ++i)
            levels[i] = analyser.getLevel (i);

        for (int pass = 0; pass < 4; ++pass)
        {
            juce::HeapBlock<float> tmp (static_cast<size_t> (n));
            for (int i = 0; i < n; ++i)
            {
                const float a = levels[juce::jmax (0, i - 1)];
                const float b = levels[i];
                const float c = levels[juce::jmin (n - 1, i + 1)];
                const float avg = a * 0.25f + b * 0.5f + c * 0.25f;
                tmp[i] = b * (1.0f - t) + avg * t;
            }
            for (int i = 0; i < n; ++i)
                levels[i] = tmp[i];
        }

        // Trace the curve. `smooth` controls how much the band levels are
        // averaged (above); the path itself is straight segments between band
        // centres, so at smooth = 0 it stays raw/edgy and at 1 it is rounded
        // by the heavy level smoothing.
        juce::Path wave;
        wave.startNewSubPath (plot.getX() + gap, baseY);
        for (int i = 0; i < n; ++i)
        {
            const float x = plot.getX() + gap + i * (bandWidth + gap) + bandWidth * 0.5f;
            const float y = baseY - levels[i] * plot.getHeight();
            wave.lineTo (x, y);
        }
        wave.lineTo (plot.getRight() - gap, baseY);
        wave.closeSubPath();

        // Brighter at the top, darker toward the bottom.
        juce::ColourGradient grad (lf.getTeal().brighter (0.35f), 0.0f, plot.getY(),
                                   lf.getTeal().darker (0.85f), 0.0f, plot.getBottom(), false);
        g.setGradientFill (grad);
        g.fillPath (wave);

        // Bright outline tracing the waveform.
        g.setColour (lf.getTeal().brighter (0.5f));
        g.strokePath (wave, juce::PathStrokeType (1.5f));

        // Smooth peak-hold wave: per-band peaks, smoothed with the same
        // amount as the main curve and traced as a matching spline.
        juce::HeapBlock<float> peaks (static_cast<size_t> (n));
        for (int i = 0; i < n; ++i)
            peaks[i] = analyser.getPeak (i);

        for (int pass = 0; pass < 4; ++pass)
        {
            juce::HeapBlock<float> tmp (static_cast<size_t> (n));
            for (int i = 0; i < n; ++i)
            {
                const float a = peaks[juce::jmax (0, i - 1)];
                const float b = peaks[i];
                const float c = peaks[juce::jmin (n - 1, i + 1)];
                const float avg = a * 0.25f + b * 0.5f + c * 0.25f;
                tmp[i] = b * (1.0f - t) + avg * t;
            }
            for (int i = 0; i < n; ++i)
                peaks[i] = tmp[i];
        }

        juce::HeapBlock<juce::Point<float>> ppts (static_cast<size_t> (n));
        for (int i = 0; i < n; ++i)
        {
            const float x = plot.getX() + gap + i * (bandWidth + gap) + bandWidth * 0.5f;
            const float y = baseY - peaks[i] * plot.getHeight();
            ppts[i] = { x, y };
        }

        juce::Path peakWave;
        peakWave.startNewSubPath (ppts[0]);
        for (int i = 0; i < n - 1; ++i)
        {
            const juce::Point<float> mid = { (ppts[i].x + ppts[i + 1].x) * 0.5f,
                                             (ppts[i].y + ppts[i + 1].y) * 0.5f };
            peakWave.quadraticTo (ppts[i], mid);
        }
        peakWave.quadraticTo (ppts[n - 1], ppts[n - 1]);
        g.setColour (lf.getPeak());
        g.strokePath (peakWave, juce::PathStrokeType (2.0f));
    }

    void drawLED (juce::Graphics& g, int n, const juce::Rectangle<float>& plot,
                  float gap, float bandWidth, float baseY)
    {
        const int leds = juce::jmax (1, ledCount);
        const float segH = plot.getHeight() / static_cast<float> (leds);
        const float blockLen = juce::jmax (1.0f, segH - 1.0f);

        for (int i = 0; i < n; ++i)
        {
            const float level = analyser.getLevel (i);
            const float peak  = analyser.getPeak (i);

            const int litCount  = juce::jlimit (0, leds, juce::roundToInt (level * leds));
            const int peakBlock = juce::jlimit (0, leds, juce::roundToInt (peak  * leds)); // top lit block (1-based)

            const float x = plot.getX() + gap + i * (bandWidth + gap);

            for (int b = 0; b < leds; ++b)
            {
                const float blockBottom = baseY - b * segH;
                const float blockTop    = blockBottom - blockLen;

                if (b < litCount)
                {
                    const float frac = (b + 0.5f) / static_cast<float> (leds);
                    g.setColour (lf.getTeal().withMultipliedBrightness (0.35f + 0.65f * frac));
                    g.fillRect (x, blockTop, bandWidth, blockLen);
                }

                // Peak honours the same discrete blocks: draw the peak block in the
                // peak colour (a single, fully-filled block).
                if (b == peakBlock - 1)
                {
                    g.setColour (lf.getPeak());
                    g.fillRect (x, blockTop, bandWidth, blockLen);
                }
            }
        }
    }

    Analyser& analyser;
    juce::AudioProcessorValueTreeState& params;
    BeamgridLookAndFeel& lf;

    int displayMode = ModeBars;
    int ledCount = 16;
    float smoothAmount = 0.35f;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (AnalyserComponent)
};