#pragma once

#include "PluginProcessor.h"

#include <JuceHeader.h>

#include <array>
#include <functional>
#include <memory>
#include <cmath>

namespace MindballColors
{
    inline const juce::Colour bg         { 0xff171718 };
    inline const juce::Colour arcBg      { 0xff292a2b };
    inline const juce::Colour accent     { 0xff6fc1ff };
    inline const juce::Colour textDim    { 0xff757575 };
    inline const juce::Colour textBright { 0xffe6e6e6 };
    inline const juce::Colour meterGreen { 0xff45a9f9 };
    inline const juce::Colour meterRed   { 0xffff2c6d };
}

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

namespace Presets
{
    struct Definition
    {
        const char* name;
        float feedback;
        float loCut;
        float hiCut;
        float timeMs;
        int   timeSyncIndex;
        float dryWet;
        bool  sync;
        int   mode;
        bool  doubleTap;
        bool  center;
        bool  autoPan;
        float panDepth;
    };

    inline constexpr Definition all[] = {
        { "Default",           0.35f,  100.0f, 12000.0f,  300.0f, 4, 0.40f, false, 0, false, false, false, 1.00f },
        { "Slapback",          0.20f,   80.0f, 15000.0f,  120.0f, 4, 0.30f, false, 0, false, false, false, 1.00f },
        { "Analog Echo",       0.45f,  120.0f,  5000.0f,  350.0f, 4, 0.35f, false, 0, false, false, false, 1.00f },
        { "Tape Echo",         0.55f,  100.0f,  3000.0f,  450.0f, 4, 0.40f, false, 0, false, false, false, 1.00f },
        { "Dub Delay",         0.70f,  150.0f,  2000.0f,  600.0f, 4, 0.50f, false, 0, false, false, false, 1.00f },
        { "Ping-Pong",         0.45f,  100.0f, 10000.0f,  400.0f, 4, 0.40f, false, 2, false, false, false, 1.00f },
        { "Wide Ping-Pong",    0.40f,  100.0f, 10000.0f,  500.0f, 4, 0.45f, false, 2, true,  false, false, 1.00f },
        { "SuperPong",         0.50f,  100.0f,  8000.0f,  350.0f, 4, 0.45f, false, 3, false, false, false, 1.00f },
        { "Sync 1/16",         0.35f,  100.0f, 12000.0f,  250.0f, 0, 0.35f, true,  0, false, false, false, 1.00f },
        { "Sync 1/8",          0.40f,  100.0f, 12000.0f,  250.0f, 1, 0.40f, true,  0, false, false, false, 1.00f },
        { "Sync 1/4",          0.45f,  100.0f, 12000.0f,  300.0f, 2, 0.45f, true,  0, false, false, false, 1.00f },
        { "Sync 1/2",          0.50f,  100.0f, 12000.0f,  300.0f, 4, 0.45f, true,  0, false, false, false, 1.00f },
        { "Sync 3/4",          0.55f,  100.0f, 12000.0f,  300.0f, 5, 0.50f, true,  0, false, false, false, 1.00f },
        { "Invert",            0.40f,  100.0f, 12000.0f,  300.0f, 4, 0.40f, false, 1, false, false, false, 1.00f },
        { "Hall Echo",         0.25f,  200.0f,  8000.0f, 1200.0f, 4, 0.30f, false, 0, false, false, false, 1.00f },
        { "Whale Song",        0.15f,  300.0f,  6000.0f, 3000.0f, 4, 0.50f, false, 0, false, false, false, 1.00f },
        { "Filtered Space",    0.55f,  300.0f,  4000.0f,  900.0f, 4, 0.45f, false, 0, false, false, false, 1.00f },
        { "Auto-Pan Delay",    0.35f,  100.0f, 12000.0f,  250.0f, 4, 0.40f, false, 0, false, false, true,  1.00f },
        { "Centered Pong",     0.60f,  100.0f,  8000.0f,  500.0f, 4, 0.45f, false, 2, false, true,  false, 1.00f },
        { "Clean Echo",        0.15f,   60.0f, 16000.0f,  280.0f, 4, 0.25f, false, 0, false, false, false, 1.00f },
    };

    inline constexpr int count = static_cast<int> (std::size (all));
}

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

class Knob final : public juce::Slider
{
public:
    Knob (const juce::String& labelText, double defaultValue)
        : label (labelText)
    {
        setSliderStyle (juce::Slider::SliderStyle::RotaryVerticalDrag);
        setTextBoxStyle (juce::Slider::NoTextBox, false, 0, 0);
        setDoubleClickReturnValue (true, defaultValue);
        setColour (juce::Slider::ColourIds::thumbColourId, MindballColors::accent);
    }

    void setValueTextFunction (std::function<juce::String (double)> fn)
    {
        valueTextFn = std::move (fn);
    }

    void paint (juce::Graphics& g) override
    {
        const auto area = getLocalBounds().toFloat();
        const float cx = area.getCentreX();
        const float cy = area.getCentreY() - 8.0f;
        const float radius = juce::jmin (area.getWidth(), area.getHeight()) * 0.30f;

        const float range = static_cast<float> (getMaximum()) - static_cast<float> (getMinimum());
        const float norm = juce::jlimit (0.0f, 1.0f,
                                         range > 0.0f
                                             ? (static_cast<float> (getValue()) - static_cast<float> (getMinimum())) / range
                                             : 0.0f);

        const float sweep = juce::MathConstants<float>::twoPi * 0.75f;

        // JUCE's addCentredArc measures clockwise from the top, so the arc
        // angles are the screen angles shifted by +90 degrees.
        const float arcStart = juce::degreesToRadians (225.0f); // down-left
        const float arcEnd   = arcStart + sweep;                // down-right

        juce::Path arc;
        arc.addCentredArc (cx, cy, radius, radius, 0.0f, arcStart, arcEnd, true);
        g.setColour (MindballColors::arcBg);
        g.strokePath (arc, juce::PathStrokeType (3.0f,
                       juce::PathStrokeType::JointStyle::curved,
                       juce::PathStrokeType::EndCapStyle::rounded));

        juce::Path valueArc;
        valueArc.addCentredArc (cx, cy, radius, radius, 0.0f, arcStart, arcStart + sweep * norm, true);
        g.setColour (MindballColors::accent);
        g.strokePath (valueArc, juce::PathStrokeType (3.0f,
                            juce::PathStrokeType::JointStyle::curved,
                            juce::PathStrokeType::EndCapStyle::rounded));

        if (valueTextFn != nullptr)
        {
            const juce::String valueText = valueTextFn (getValue());
            if (valueText.isNotEmpty())
            {
                g.setColour (MindballColors::textBright);
                g.setFont (juce::Font (juce::FontOptions (9.0f)));
                g.drawFittedText (valueText, getLocalBounds().removeFromBottom (32).removeFromTop (16),
                                  juce::Justification::centred, 1);
            }
        }

        g.setColour (MindballColors::textDim);
        g.setFont (juce::Font (juce::FontOptions (9.0f)));
        g.drawFittedText (label, getLocalBounds().removeFromBottom (16),
                          juce::Justification::centredBottom, 1);
    }

private:
    juce::String label;
    std::function<juce::String (double)> valueTextFn;
};

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

class LevelMeter final : public juce::Component
{
public:
    explicit LevelMeter (const juce::String& meterName)
        : name (meterName)
    {
    }

    void update (float linL, float linR, float decay)
    {
        const bool changedL = updateChannel (0, linL, decay);
        const bool changedR = updateChannel (1, linR, decay);

        if (changedL || changedR)
            repaint();
    }

    void paint (juce::Graphics& g) override
    {
        constexpr int steps = 15;

        auto b = getLocalBounds().toFloat();
        g.setColour (MindballColors::textDim);
        g.setFont (juce::Font (juce::FontOptions (9.0f)));
        g.drawText (name, b.removeFromTop (13.0f), juce::Justification::centred, false);

        const float rowH = (b.getHeight() - 4.0f) * 0.5f;
        const float segGap = 1.0f;
        const float segW = (b.getWidth() - (steps - 1) * segGap) / static_cast<float> (steps);

        for (int ch = 0; ch < 2; ++ch)
        {
            auto row = b.removeFromTop (rowH);

            for (int s = 0; s < steps; ++s)
            {
                const auto seg = juce::Rectangle<float> (row.getX() + s * (segW + segGap),
                                                         row.getY() + 2.0f, segW, rowH - 4.0f);
                g.setColour (s < lit[ch] ? MindballColors::meterGreen : MindballColors::arcBg);
                g.fillRect (seg);
            }

            if (pk[ch] > 0)
            {
                const int peakSeg = juce::jmin (pk[ch], steps - 1);
                const auto seg = juce::Rectangle<float> (row.getX() + peakSeg * (segW + segGap),
                                                         row.getY() + 2.0f, segW, rowH - 4.0f);
                g.setColour (MindballColors::meterRed);
                g.fillRect (seg);
            }
        }
    }

private:
    bool updateChannel (int ch, float lin, float decay)
    {
        peaks[ch] = std::max (peaks[ch] * decay, lin);

        const int newLit = levelToSteps (lin);
        const int newPk  = levelToSteps (peaks[ch]);

        if (newLit == lit[ch] && newPk == pk[ch])
            return false;

        lit[ch] = newLit;
        pk[ch]  = newPk;
        return true;
    }

    static int levelToSteps (float lin)
    {
        constexpr int steps = 15;
        constexpr float dbMin = -30.0f;
        constexpr float dbPerStep = 2.0f;
        const float db = 20.0f * std::log10 (lin > 0.0f ? lin : 1e-9f);
        return juce::jlimit (0, steps, juce::roundToInt ((db - dbMin) / dbPerStep));
    }

    juce::String name;
    int lit[2]  = { 0, 0 };
    int pk[2]   = { 0, 0 };
    float peaks[2] = { 0.0f, 0.0f };
};

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

class PillToggle final : public juce::Button
{
public:
    explicit PillToggle (const juce::String& text)
        : juce::Button (text)
    {
        setClickingTogglesState (true);
    }

    void setInverted (bool shouldInvert)
    {
        inverted = shouldInvert;
        repaint();
    }

    void paintButton (juce::Graphics& g, bool, bool) override
    {
        const auto b = getLocalBounds().toFloat().reduced (1.0f);
        const bool on = inverted ? ! getToggleState() : getToggleState();

        if (on)
        {
            g.setColour (MindballColors::accent);
            g.fillRoundedRectangle (b, b.getHeight() * 0.5f);
            g.setColour (MindballColors::bg);
        }
        else
        {
            g.setColour (MindballColors::arcBg);
            g.drawRoundedRectangle (b, b.getHeight() * 0.5f, 1.0f);
            g.setColour (MindballColors::textDim);
        }

        g.setFont (juce::Font (juce::FontOptions (9.0f)));
        g.drawText (getButtonText(), getLocalBounds(), juce::Justification::centred, false);
    }

private:
    bool inverted = false;
};

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

class ModeToggle final : public juce::Button, private juce::AudioProcessorParameter::Listener
{
public:
    explicit ModeToggle (juce::AudioProcessorValueTreeState& apvts)
        : juce::Button ("Mode"),
          param (static_cast<juce::AudioParameterChoice*> (apvts.getParameter (ParameterIDs::mode)))
    {
        if (param != nullptr)
            param->addListener (this);
    }

    ~ModeToggle() override
    {
        if (param != nullptr)
            param->removeListener (this);
    }

    void clicked() override
    {
        if (param == nullptr)
            return;

        const int next = (param->getIndex() + 1) % param->choices.size();
        param->beginChangeGesture();
        param->setValueNotifyingHost (param->convertTo0to1 (next));
        param->endChangeGesture();
    }

    void parameterValueChanged (int, float) override
    {
        juce::MessageManager::callAsync ([this] { repaint(); });
    }

    void parameterGestureChanged (int, bool) override {}

    void paintButton (juce::Graphics& g, bool, bool) override
    {
        const auto b = getLocalBounds().toFloat().reduced (1.0f);
        const int mode = param != nullptr ? param->getIndex() : 0;
        const bool on = mode != 0;

        if (on)
        {
            g.setColour (MindballColors::accent);
            g.fillRoundedRectangle (b, b.getHeight() * 0.5f);
            g.setColour (MindballColors::bg);
        }
        else
        {
            g.setColour (MindballColors::arcBg);
            g.drawRoundedRectangle (b, b.getHeight() * 0.5f, 1.0f);
            g.setColour (MindballColors::textDim);
        }

        g.setFont (juce::Font (juce::FontOptions (9.0f)));
        g.drawText (param != nullptr ? param->getCurrentChoiceName() : "Mode",
                    getLocalBounds(), juce::Justification::centred, false);
    }

private:
    juce::AudioParameterChoice* param;
};

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

class ScaleButton final : public juce::Button
{
public:
    explicit ScaleButton (std::function<void (float)> onPick)
        : juce::Button ("UI Scale"), pickCallback (std::move (onPick))
    {
        setScale (1.5f);
    }

    void setScale (float s)
    {
        scale = s;
        setButtonText (juce::String (juce::roundToInt (scale * 100.0f)) + "%");
        repaint();
    }

    void paintButton (juce::Graphics& g, bool, bool) override
    {
        const auto b = getLocalBounds().toFloat().reduced (1.0f);
        g.setColour (MindballColors::arcBg);
        g.drawRoundedRectangle (b, b.getHeight() * 0.5f, 1.0f);
        g.setColour (MindballColors::textBright);
        g.setFont (juce::Font (juce::FontOptions (11.0f)));
        g.drawText (getButtonText(), getLocalBounds(), juce::Justification::centred, false);
    }

    void clicked() override
    {
        const float options[] = { 0.5f, 0.75f, 1.0f, 1.25f, 1.5f, 2.0f, 2.5f, 3.0f };

        juce::PopupMenu menu;
        for (int i = 0; i < 8; ++i)
            menu.addItem (i + 1, juce::String (juce::roundToInt (options[i] * 100.0f)) + "%",
                          true, scale == options[i]);

        menu.showMenuAsync (juce::PopupMenu::Options().withTargetComponent (this),
                            [this, options] (int result)
                            {
                                if (result >= 1 && result <= 8 && pickCallback != nullptr)
                                    pickCallback (options[result - 1]);
                            });
    }

private:
    std::function<void (float)> pickCallback;
    float scale = 1.5f;
};

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

class PresetButton final : public juce::Button
{
public:
    explicit PresetButton (std::function<void (int)> onPick)
        : juce::Button ("Presets"), pickCallback (std::move (onPick))
    {
    }

    void setCurrent (int index)
    {
        current = index;
        setButtonText (juce::String (Presets::all[index].name));
        repaint();
    }

    void setCurrentProvider (std::function<int()> provider)
    {
        currentProvider = std::move (provider);
    }

    void paintButton (juce::Graphics& g, bool, bool) override
    {
        const auto b = getLocalBounds().toFloat().reduced (1.0f);
        g.setColour (MindballColors::arcBg);
        g.drawRoundedRectangle (b, b.getHeight() * 0.5f, 1.0f);
        g.setColour (MindballColors::textBright);
        g.setFont (juce::Font (juce::FontOptions (11.0f)));
        g.drawText (getButtonText(), b, juce::Justification::centred, false);
    }

    void clicked() override
    {
        const int checked = currentProvider != nullptr ? currentProvider() : current;

        juce::PopupMenu menu;
        for (int i = 0; i < Presets::count; ++i)
            menu.addItem (i + 1, juce::String (Presets::all[i].name), true, i == checked);

        menu.showMenuAsync (juce::PopupMenu::Options().withTargetComponent (this),
                            [this] (int result)
                            {
                                if (result >= 1 && result <= Presets::count && pickCallback != nullptr)
                                    pickCallback (result - 1);
                            });
    }

private:
    std::function<void (int)> pickCallback;
    std::function<int()> currentProvider;
    int current = 0;
};

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

class UI;

class MindballAudioProcessorEditor final : public juce::AudioProcessorEditor
{
public:
    explicit MindballAudioProcessorEditor (MindballAudioProcessor& p);
    ~MindballAudioProcessorEditor() override;

    void paint (juce::Graphics&) override;
    void resized() override;

private:
    static constexpr int baseW = 736;
    static constexpr int baseH = 320;

    void setUiScale (float s);
    void applyPreset (int index);
    int findMatchingPreset() const;
    bool presetMatches (const Presets::Definition& p) const;
    void setParam (const char* paramID, float value);
    void setChoiceParam (const char* paramID, int index);

    MindballAudioProcessor& proc;
    std::unique_ptr<UI> ui;
    ScaleButton scaleButton;
    PresetButton presetButton;
    float uiScale = 1.5f;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (MindballAudioProcessorEditor)
};