|  | #include "plugin.hpp"
float aliasSuppressedSaw(const float* phases, float pw) {
	float sawBuffer[3];
	for (int i = 0; i < 3; ++i) {
		float p = 2 * phases[i] - 1.0; 		// range -1 to +1
		float pwp = p + 2 * pw;				// phase after pw (pw in [0, 1])
		pwp += simd::ifelse(pwp > 1, -2, simd::ifelse(pwp < -1, +2, 0));     			// modulo on [-1, +1]
		sawBuffer[i] = (pwp * pwp * pwp - pwp) / 6.0;	// eq 11
	}
	return (sawBuffer[0] - 2.0 * sawBuffer[1] + sawBuffer[2]);
}
float aliasSuppressedOffsetSaw(const float* phases, float pw) {
	float sawOffsetBuff[3];
	for (int i = 0; i < 3; ++i) {
		float pwp = 2 * phases[i] - 2 * pw; 		// range -1 to +1
		
		pwp += simd::ifelse(pwp > 1, -2, 0);     			// modulo on [-1, +1]
		sawOffsetBuff[i] = (pwp * pwp * pwp - pwp) / 6.0;	// eq 11
	}
	return (sawOffsetBuff[0] - 2.0 * sawOffsetBuff[1] + sawOffsetBuff[2]);
}
struct Octaves : Module {
	enum ParamId {
		PWM_CV_PARAM,
		OCTAVE_PARAM,
		TUNE_PARAM,
		PWM_PARAM,
		RANGE_PARAM,
		GAIN_01F_PARAM,
		GAIN_02F_PARAM,
		GAIN_04F_PARAM,
		GAIN_08F_PARAM,
		GAIN_16F_PARAM,
		GAIN_32F_PARAM,
		PARAMS_LEN
	};
	enum InputId {
		VOCT1_INPUT,
		VOCT2_INPUT,
		SYNC_INPUT,
		PWM_INPUT,
		GAIN_01F_INPUT,
		GAIN_02F_INPUT,
		GAIN_04F_INPUT,
		GAIN_08F_INPUT,
		GAIN_16F_INPUT,
		GAIN_32F_INPUT,
		INPUTS_LEN
	};
	enum OutputId {
		OUT_01F_OUTPUT,
		OUT_02F_OUTPUT,
		OUT_04F_OUTPUT,
		OUT_08F_OUTPUT,
		OUT_16F_OUTPUT,
		OUT_32F_OUTPUT,
		OUT_OUTPUT,
		OUT2_OUTPUT,
		OUT_01F_OUTPUT_ALT,
		OUT_02F_OUTPUT_ALT,
		OUT_04F_OUTPUT_ALT,
		OUT_08F_OUTPUT_ALT,
		OUT_16F_OUTPUT_ALT,
		OUT_32F_OUTPUT_ALT,
		OUTPUTS_LEN
	};
	enum LightId {
		LIGHTS_LEN
	};
	bool limitPW = true;
	bool removePulseDC = false;
	int oversamplingIndex = 0;
	Octaves() {
		config(PARAMS_LEN, INPUTS_LEN, OUTPUTS_LEN, LIGHTS_LEN);
		configParam(PWM_CV_PARAM, 0.f, 1.f, 1.f, "PWM CV attenuater");
		auto octParam = configSwitch(OCTAVE_PARAM, 0.f, 6.f, 4.f, "Octave", {"C1", "C2", "C3", "C4", "C5", "C6", "C7"});
		octParam->snapEnabled = true;
		configParam(TUNE_PARAM, -1.f, 1.f, 0.f, "Tune");
		configParam(PWM_PARAM, 0.5f, 0.f, 0.5f, "PWM");
		auto rangeParam = configSwitch(RANGE_PARAM, 0.f, 2.f, 0.f, "Range", {"VCO: Full", "VCO: Octave", "VCO: Semitone"});
		rangeParam->snapEnabled = true;
		configParam(GAIN_01F_PARAM, 0.f, 1.f, 0.f, "Gain Fundamental");
		configParam(GAIN_02F_PARAM, 0.f, 1.f, 0.f, "Gain x2 Fundamental");
		configParam(GAIN_04F_PARAM, 0.f, 1.f, 0.f, "Gain x4 Fundamental");
		configParam(GAIN_08F_PARAM, 0.f, 1.f, 0.f, "Gain x8 Fundamental");
		configParam(GAIN_16F_PARAM, 0.f, 1.f, 0.f, "Gain x16 Fundamental");
		configParam(GAIN_32F_PARAM, 0.f, 1.f, 0.f, "Gain x32 Fundamental");
		configInput(VOCT1_INPUT, "V/Octave 1");
		configInput(VOCT2_INPUT, "V/Octave 2");
		configInput(SYNC_INPUT, "Sync");
		configInput(PWM_INPUT, "PWM");
		configInput(GAIN_01F_INPUT, "Gain x1F CV");
		configInput(GAIN_02F_INPUT, "Gain x1F CV");
		configInput(GAIN_04F_INPUT, "Gain x1F CV");
		configInput(GAIN_08F_INPUT, "Gain x1F CV");
		configInput(GAIN_16F_INPUT, "Gain x1F CV");
		configInput(GAIN_32F_INPUT, "Gain x1F CV");
		configOutput(OUT_01F_OUTPUT, "x1F");
		configOutput(OUT_02F_OUTPUT, "x2F");
		configOutput(OUT_04F_OUTPUT, "x4F");
		configOutput(OUT_08F_OUTPUT, "x8F");
		configOutput(OUT_16F_OUTPUT, "x16F");
		configOutput(OUT_32F_OUTPUT, "x32F");
		configOutput(OUT_OUTPUT, "debug");
	}
	float phase = 0.f;
	float phases[3];
	bool forceNaive = false;
	void process(const ProcessArgs& args) override {
		float pitch = params[TUNE_PARAM].getValue() + inputs[VOCT1_INPUT].getVoltage() + inputs[VOCT2_INPUT].getVoltage();
		pitch += params[OCTAVE_PARAM].getValue() - 3;
		float freq = dsp::FREQ_C4 * dsp::exp2_taylor5(pitch);
		// -1 to +1
		float pwmCV = params[PWM_CV_PARAM].getValue() * clamp(inputs[PWM_INPUT].getVoltage() / 10.f, -1.f, 1.f);
		const float pulseWidthLimit = limitPW ? 0.05f : 0.0f;
		
		// pwm in [-0.25 : +0.25]
		float pwm = clamp(0.5 - params[PWM_PARAM].getValue() + 0.5 * pwmCV, -0.5f + pulseWidthLimit, 0.5f - pulseWidthLimit);
		pwm /= 2.0;
		float deltaPhase = freq * args.sampleTime;
		phase += deltaPhase;
		phase -= std::floor(phase);
		float sum = 0.f;
		float sumNaive = 0.f;
		for (int c = 0; c < 6; c++) {
			// derive phases for higher octaves from base phase (this keeps things in sync!)
			const float n = (float)(1 << c);
			// this is on [0, 1]
			const float effectivePhaseRaw = n * std::fmod(phase, 1 / n);			
			// this is on [0, 1], and offset in time by 0.25
			const float effectivePhase = std::fmod(effectivePhaseRaw + 0.25, 1);
			const float effectiveDeltaPhase = deltaPhase * n;
			const float gainCV = clamp(inputs[GAIN_01F_INPUT + c].getNormalVoltage(10.f) / 10.f, 0.f, 1.0f);
			const float gain = params[GAIN_01F_PARAM + c].getValue() * gainCV;
			// floating point arithmetic doesn't work well at low frequencies, specifically because the finite difference denominator
			// becomes tiny - we check for that scenario and use naive / 1st order waveforms in that frequency regime (as aliasing isn't
			// a problem there). With no oversampling, at 44100Hz, the threshold frequency is 44.1Hz.
			const bool lowFreqRegime = forceNaive; //effectiveDeltaPhase < 1e-3 || forceNaive;
			//float waveTri = 1.0 - 2.0 * std::abs(2.f * effectivePhase - 1.0);
			// float dpwOrder1 = (waveTri > 2 * pwm - 1) ? 1.0 : -1.0;
			float dpwOrder1 = gain * (effectivePhaseRaw > pwm + 0.25 && effectivePhaseRaw < 0.75 - pwm ? -1.0 : +1.0);
			dpwOrder1 -= removePulseDC ? 2.f * (0.5f - pwm) : 0.f;
			// dpwOrder1 = waveTri * gain;
			sumNaive += dpwOrder1;
			outputs[OUT_01F_OUTPUT_ALT + c].setVoltage(dpwOrder1);
			float outForOctave = dpwOrder1;
			if (!lowFreqRegime) {
				phases[0] = effectivePhase - 2 * effectiveDeltaPhase + (effectivePhase < 2 * effectiveDeltaPhase ? 1.f : 0.f);
				phases[1] = effectivePhase - 1 * effectiveDeltaPhase + (effectivePhase < 1 * effectiveDeltaPhase ? 1.f : 0.f);
				phases[2] = effectivePhase;
				float saw = aliasSuppressedSaw(phases, pwm);
				float sawOffset = aliasSuppressedOffsetSaw(phases, pwm);
				float denominatorInv = 0.25 / (effectiveDeltaPhase * effectiveDeltaPhase);
				float dpwOrder3 = gain * (sawOffset - saw) * denominatorInv;
				const float pulseDCOffset = (!removePulseDC) * 4.f * pwm * gain;
				dpwOrder3 += pulseDCOffset;
				outForOctave = dpwOrder3;
			}
			sum += outForOctave;
			sum = clamp(sum, -1.f, 1.f);
			if (outputs[OUT_01F_OUTPUT + c].isConnected()) {
				outputs[OUT_01F_OUTPUT + c].setVoltage(5 * sum);
				sum = 0.f;
			}
			if (c == 0) {
				outputs[OUT_OUTPUT].setVoltage(effectivePhase);
				
				float saw = aliasSuppressedSaw(phases, 2*pwm);
				float sawOffset = aliasSuppressedOffsetSaw(phases, 2*pwm);
				float denominatorInv = 0.25 / (effectiveDeltaPhase * effectiveDeltaPhase);
				float dpwOrder3_ = gain * (-saw) * denominatorInv;
				outputs[OUT2_OUTPUT].setVoltage(dpwOrder3_);
			}
		}
		//outputs[OUT_OUTPUT].setVoltage(sum);
		//outputs[OUT2_OUTPUT].setVoltage(phase > 0.5 ? +5 : -5);
	}
	json_t* dataToJson() override {
		json_t* rootJ = json_object();
		json_object_set_new(rootJ, "removePulseDC", json_boolean(removePulseDC));
		json_object_set_new(rootJ, "limitPW", json_boolean(limitPW));
		json_object_set_new(rootJ, "forceNaive", json_boolean(forceNaive));
		// TODO:
		// json_object_set_new(rootJ, "oversamplingIndex", json_integer(oversampler[0].getOversamplingIndex()));
		return rootJ;
	}
	void dataFromJson(json_t* rootJ) override {
		json_t* removePulseDCJ = json_object_get(rootJ, "removePulseDC");
		if (removePulseDCJ) {
			removePulseDC = json_boolean_value(removePulseDCJ);
		}
		json_t* limitPWJ = json_object_get(rootJ, "limitPW");
		if (limitPWJ) {
			limitPW = json_boolean_value(limitPWJ);
		}
		json_t* forceNaiveJ = json_object_get(rootJ, "forceNaive");
		if (forceNaiveJ) {
			forceNaive = json_boolean_value(forceNaiveJ);
		}
		json_t* oversamplingIndexJ = json_object_get(rootJ, "oversamplingIndex");
		if (oversamplingIndexJ) {
			oversamplingIndex = json_integer_value(oversamplingIndexJ);
			onSampleRateChange();
		}
	}
};
struct OctavesWidget : ModuleWidget {
	OctavesWidget(Octaves* module) {
		setModule(module);
		setPanel(createPanel(asset::plugin(pluginInstance, "res/panels/Octaves.svg")));
		addChild(createWidget<Knurlie>(Vec(RACK_GRID_WIDTH, 0)));
		addChild(createWidget<Knurlie>(Vec(box.size.x - 2 * RACK_GRID_WIDTH, 0)));
		addChild(createWidget<Knurlie>(Vec(RACK_GRID_WIDTH, RACK_GRID_HEIGHT - RACK_GRID_WIDTH)));
		addChild(createWidget<Knurlie>(Vec(box.size.x - 2 * RACK_GRID_WIDTH, RACK_GRID_HEIGHT - RACK_GRID_WIDTH)));
		addParam(createParamCentered<BefacoTinyKnobLightGrey>(mm2px(Vec(52.138, 15.037)), module, Octaves::PWM_CV_PARAM));
		addParam(createParam<CKSSVert7>(mm2px(Vec(22.171, 30.214)), module, Octaves::OCTAVE_PARAM));
		addParam(createParamCentered<BefacoTinyKnobLightGrey>(mm2px(Vec(10.264, 33.007)), module, Octaves::TUNE_PARAM));
		addParam(createParamCentered<Davies1900hLargeRedKnob>(mm2px(Vec(45.384, 40.528)), module, Octaves::PWM_PARAM));
		addParam(createParam<CKSSThreeHorizontal>(mm2px(Vec(6.023, 48.937)), module, Octaves::RANGE_PARAM));
		addParam(createParam<BefacoSlidePotSmall>(mm2px(Vec(2.9830, 60.342)), module, Octaves::GAIN_01F_PARAM));
		addParam(createParam<BefacoSlidePotSmall>(mm2px(Vec(12.967, 60.342)), module, Octaves::GAIN_02F_PARAM));
		addParam(createParam<BefacoSlidePotSmall>(mm2px(Vec(22.951, 60.342)), module, Octaves::GAIN_04F_PARAM));
		addParam(createParam<BefacoSlidePotSmall>(mm2px(Vec(32.936, 60.342)), module, Octaves::GAIN_08F_PARAM));
		addParam(createParam<BefacoSlidePotSmall>(mm2px(Vec(42.920, 60.342)), module, Octaves::GAIN_16F_PARAM));
		addParam(createParam<BefacoSlidePotSmall>(mm2px(Vec(52.905, 60.342)), module, Octaves::GAIN_32F_PARAM));
		addInput(createInputCentered<BefacoInputPort>(mm2px(Vec(5.247, 15.181)), module, Octaves::VOCT1_INPUT));
		addInput(createInputCentered<BefacoInputPort>(mm2px(Vec(15.282, 15.181)), module, Octaves::VOCT2_INPUT));
		addInput(createInputCentered<BefacoInputPort>(mm2px(Vec(25.316, 15.181)), module, Octaves::SYNC_INPUT));
		addInput(createInputCentered<BefacoInputPort>(mm2px(Vec(37.092, 15.135)), module, Octaves::PWM_INPUT));
		addInput(createInputCentered<BefacoInputPort>(mm2px(Vec(5.247, 100.492)), module, Octaves::GAIN_01F_INPUT));
		addInput(createInputCentered<BefacoInputPort>(mm2px(Vec(15.282, 100.492)), module, Octaves::GAIN_02F_INPUT));
		addInput(createInputCentered<BefacoInputPort>(mm2px(Vec(25.316, 100.492)), module, Octaves::GAIN_04F_INPUT));
		addInput(createInputCentered<BefacoInputPort>(mm2px(Vec(35.35, 100.492)), module, Octaves::GAIN_08F_INPUT));
		addInput(createInputCentered<BefacoInputPort>(mm2px(Vec(45.384, 100.492)), module, Octaves::GAIN_16F_INPUT));
		addInput(createInputCentered<BefacoInputPort>(mm2px(Vec(55.418, 100.492)), module, Octaves::GAIN_32F_INPUT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(5.247, 113.508)), module, Octaves::OUT_01F_OUTPUT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(15.282, 113.508)), module, Octaves::OUT_02F_OUTPUT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(25.316, 113.508)), module, Octaves::OUT_04F_OUTPUT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(35.35, 113.508)), module, Octaves::OUT_08F_OUTPUT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(45.384, 113.508)), module, Octaves::OUT_16F_OUTPUT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(55.418, 113.508)), module, Octaves::OUT_32F_OUTPUT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(25.316, 106.508)), module, Octaves::OUT_OUTPUT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(35.316, 106.508)), module, Octaves::OUT2_OUTPUT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(5.247,  120.508)), module, Octaves::OUT_01F_OUTPUT_ALT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(15.282, 120.508)), module, Octaves::OUT_02F_OUTPUT_ALT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(25.316, 120.508)), module, Octaves::OUT_04F_OUTPUT_ALT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(35.35,  120.508)), module, Octaves::OUT_08F_OUTPUT_ALT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(45.384, 120.508)), module, Octaves::OUT_16F_OUTPUT_ALT));
		addOutput(createOutputCentered<BefacoOutputPort>(mm2px(Vec(55.418, 120.508)), module, Octaves::OUT_32F_OUTPUT_ALT));
	}
	void appendContextMenu(Menu* menu) override {
		Octaves* module = dynamic_cast<Octaves*>(this->module);
		assert(module);
		menu->addChild(new MenuSeparator());
		menu->addChild(createSubmenuItem("Hardware compatibility", "",
		[ = ](Menu * menu) {
			menu->addChild(createBoolPtrMenuItem("Limit pulsewidth (5\%-95\%)", "", &module->limitPW));
			menu->addChild(createBoolPtrMenuItem("Remove pulse DC", "", &module->removePulseDC));
		}
		                                ));
		menu->addChild(createIndexSubmenuItem("Oversampling",
		{"Off", "x2", "x4", "x8"},
		[ = ]() {
			return module->oversamplingIndex;
		},
		[ = ](int mode) {
			module->oversamplingIndex = mode;
			module->onSampleRateChange();
		}
		                                     ));
		menu->addChild(createBoolPtrMenuItem("Force naive waveforms", "", &module->forceNaive));
	}
};
Model* modelOctaves = createModel<Octaves, OctavesWidget>("Octaves");
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