#include "PluginProcessor.h"
#include "PluginEditor.h"

// ---------------------------------------------------------------------------

class RMX19AudioProcessor::FxEngine
{
public:
    void prepare (double sampleRate, int maxSamples)
    {
        sr = sampleRate;
        chorusL.prepare ({ sampleRate, 1u, (juce::uint32) maxSamples });
        chorusR.prepare ({ sampleRate, 1u, (juce::uint32) maxSamples });
        delL.prepare    ({ sampleRate, 1u, (juce::uint32) maxSamples });
        delR.prepare    ({ sampleRate, 1u, (juce::uint32) maxSamples });

        const int maxDelay = (int) (sampleRate * 1.5);
        chorusL.setMaximumDelayInSamples (maxDelay);
        chorusR.setMaximumDelayInSamples (maxDelay);
        delL.setMaximumDelayInSamples (maxDelay);
        delR.setMaximumDelayInSamples (maxDelay);
    }

    void reset()
    {
        chorusL.reset(); chorusR.reset();
        delL.reset(); delR.reset();
        chPh = 0.0;
    }

    void process (const VParams& p, float* L, float* R, int num)
    {
        const int type = (int) p.fxType;
        if (type == 0) return;

        const float wet = p.fxAmt;
        const float dry = 1.0f - wet * 0.5f;
        const float chBase = 0.008f * (float) sr;          // 8 ms chorus base
        const float chDepth = 0.0035f * (float) sr;        // +-3.5 ms wobble
        const float delSamples = (float) (p.fxTime * sr);
        const float feedback = 0.40f;

        for (int s = 0; s < num; ++s)
        {
            const float inL = L[s], inR = R[s];
            float outL = inL * dry, outR = inR * dry;

            if (type == 1 || type == 3)
            {
                const double rate = type == 3 ? 0.55 : 0.38;
                chPh += rate / sr;
                if (chPh >= 1.0) chPh -= 1.0;
                const float m = 0.5f + 0.5f * (float) std::sin (chPh * 2.0 * juce::MathConstants<double>::pi);

                chorusL.pushSample (0, inL);
                chorusR.pushSample (0, inR);
                const float mL = chorusL.popSample (0, chBase + chDepth * m);
                const float mR = chorusR.popSample (0, chBase + chDepth * (1.0f - m));
                outL += mL * wet * 0.7f;
                outR += mR * wet * 0.7f;
            }

            if (type == 2 || type == 3)
            {
                const float rL = delL.popSample (0, delSamples);
                const float rR = delR.popSample (0, delSamples);
                delL.pushSample (0, inL + rR * feedback);
                delR.pushSample (0, inR + rL * feedback);
                outL += rL * wet;
                outR += rR * wet;
            }

            L[s] = outL;
            R[s] = outR;
        }
    }

private:
    juce::dsp::DelayLine<float> chorusL, chorusR, delL, delR;
    double sr = 48000.0;
    double chPh = 0.0;
};

// ---------------------------------------------------------------------------

RMX19AudioProcessor::RMX19AudioProcessor()
    : AudioProcessor (BusesProperties().withOutput ("Output", juce::AudioChannelSet::stereo(), true))
    , apvts (*this, nullptr, "Params", createParams())
{
}

RMX19AudioProcessor::~RMX19AudioProcessor() {}

juce::AudioProcessorValueTreeState::ParameterLayout RMX19AudioProcessor::createParams()
{
    return prm::createLayout();
}

const juce::String RMX19AudioProcessor::getName() const { return "RMX-19"; }

void RMX19AudioProcessor::prepareToPlay (double sampleRate, int samplesPerBlock)
{
    engine.setSampleRate (sampleRate);
    engine.allNotesOff (true);
    fx = std::make_unique<FxEngine>();
    fx->prepare (sampleRate, samplesPerBlock);
}

void RMX19AudioProcessor::releaseResources()
{
    engine.allNotesOff (true);
    if (fx) fx->reset();
}

void RMX19AudioProcessor::processMidi (juce::MidiBuffer& midi, const VParams& p)
{
    (void) p;
    constexpr double bendSemis = 2.0;

    for (const auto meta : midi)
    {
        const auto msg = meta.getMessage();
        lastMidi = juce::Time::getMillisecondCounter();

        if (msg.isNoteOn())
        {
            engine.noteOn (msg.getNoteNumber(), msg.getFloatVelocity());
        }
        else if (msg.isNoteOff())
        {
            engine.noteOff (msg.getNoteNumber());
        }
        else if (msg.isPitchWheel())
        {
            engine.pitchBend ((float) ((msg.getPitchWheelValue() - 8192) / 8192.0 * bendSemis * 100.0));
        }
        else if (msg.isController())
        {
            const int cc = msg.getControllerNumber();
            const float v = msg.getControllerValue() / 127.0f;
            switch (cc)
            {
                case 64: engine.sustainPedal (msg.getControllerValue() >= 64); break;
                case 1:  engine.modWheel (v); break;
                case 7:  if (auto* par = apvts.getParameter ("vol"))     par->setValueNotifyingHost (v); break;
                case 10: if (auto* par = apvts.getParameter ("pan"))     par->setValueNotifyingHost (v * 2.0f - 1.0f); break;
                case 71: if (auto* par = apvts.getParameter ("fltres"))  par->setValueNotifyingHost (v); break;
                case 72: if (auto* par = apvts.getParameter ("ampR"))    par->setValueNotifyingHost (v); break;
                case 73: if (auto* par = apvts.getParameter ("ampA"))    par->setValueNotifyingHost (v); break;
                case 74: if (auto* par = apvts.getParameter ("fltcut"))  par->setValueNotifyingHost (v); break;
                case 76: if (auto* par = apvts.getParameter ("lforate")) par->setValueNotifyingHost (v); break;
                case 77: if (auto* par = apvts.getParameter ("lfodepth"))par->setValueNotifyingHost (v); break;
                case 91: if (auto* par = apvts.getParameter ("fxamt"))   par->setValueNotifyingHost (v); break;
                default: break;
            }
        }
    }
}

void RMX19AudioProcessor::processBlock (juce::AudioBuffer<float>& buffer, juce::MidiBuffer& midi)
{
    juce::ScopedNoDenormals noDenormals;

    const juce::uint32 start = juce::Time::getMillisecondCounter();
    const int numSamples = buffer.getNumSamples();
    const int numChannels = buffer.getNumChannels();
    if (numSamples == 0) return;

    VParams p;
    p.update (apvts);

    // patch follow
    const int sel = (int) apvts.getRawParameterValue ("patchsel")->load();
    if (sel != lastPatchParam && sel >= 0 && sel < bank.size())
    {
        lastPatchParam = sel;
        patchIndex = sel;
        bank.writeTo (sel, apvts);
    }

    processMidi (midi, p);

    const int chL = 0, chR = 1;
    float* L = buffer.getNumChannels() > 0 ? buffer.getWritePointer (juce::jmin (chL, numChannels - 1)) : nullptr;
    float* R = buffer.getNumChannels() > 1 ? buffer.getWritePointer (juce::jmin (chR, numChannels - 1)) : nullptr;

    for (int c = 0; c < numChannels; ++c)
        buffer.clear (c, 0, numSamples);

    if (L != nullptr && R != nullptr)
    {
        engine.render (p, L, R, numSamples);
        if (fx) fx->process (p, L, R, numSamples);
        if (p.vol != 1.0f) buffer.applyGain (p.vol);
    }
    else if (L != nullptr)
    {
        juce::AudioBuffer<float> dummy (1, numSamples);
        dummy.clear();
        float* dL = dummy.getWritePointer (0);
        float* dR = dummy.getWritePointer (0);
        engine.render (p, dL, dR, numSamples);
        for (int c = 0; c < numChannels; ++c)
            buffer.copyFrom (c, 0, dummy, 0, 0, numSamples);
        buffer.applyGain (p.vol);
    }

    cpu = 0.7f * cpu + 0.3f * (float) (juce::Time::getMillisecondCounter() - start);
}

void RMX19AudioProcessor::selectPatch (int i)
{
    i = juce::jlimit (0, bank.size() - 1, i);
    patchIndex = i;
    lastPatchParam = i;
    if (auto* par = apvts.getParameter ("patchsel"))
        par->setValueNotifyingHost (par->convertTo0to1 ((float) i));
    bank.writeTo (i, apvts);
}

int RMX19AudioProcessor::getNumPrograms()                    { return bank.size(); }
int RMX19AudioProcessor::getCurrentProgram()                 { return patchIndex; }

void RMX19AudioProcessor::setCurrentProgram (int index)      { selectPatch (index); }

const juce::String RMX19AudioProcessor::getProgramName (int index)
{
    if (index >= 0 && index < bank.size()) return bank.get (index).name;
    return {};
}

void RMX19AudioProcessor::changeProgramName (int, const juce::String&) {}

void RMX19AudioProcessor::getStateInformation (juce::MemoryBlock& destData)
{
    auto state = apvts.copyState();
    std::unique_ptr<juce::XmlElement> xml (state.createXml());
    copyXmlToBinary (*xml, destData);
}

void RMX19AudioProcessor::setStateInformation (const void* data, int sizeInBytes)
{
    std::unique_ptr<juce::XmlElement> xml (getXmlFromBinary (data, sizeInBytes));
    if (xml == nullptr) return;

    apvts.replaceState (juce::ValueTree::fromXml (*xml));

    const int sel = juce::jlimit (0, bank.size() - 1,
                                  (int) apvts.getRawParameterValue ("patchsel")->load());
    lastPatchParam = sel;
    patchIndex = sel;
}

juce::AudioProcessorEditor* RMX19AudioProcessor::createEditor()
{
    return new RackEditor (*this);
}

bool RMX19AudioProcessor::hasEditor() const { return true; }

juce::AudioProcessor* JUCE_CALLTYPE createPluginFilter()
{
    return new RMX19AudioProcessor();
}