import { BasicTests } from "test/helper/Basic";
import { CompareToFile } from "test/helper/CompareToFile";
import { connectTo } from "test/helper/Connect";
import { PassAudio } from "test/helper/PassAudio";
import { connect } from "Tone/core/context/ToneAudioNode";
import { Subtract } from "Tone/signal/Subtract";
import { PhaseShiftAllpass } from "./PhaseShiftAllpass";

describe("PhaseShiftAllpass", () => {

	BasicTests(PhaseShiftAllpass);

	context("PhaseShiftAllpass", () => {

		it("handles output connections", () => {
			const phaseShifter = new PhaseShiftAllpass();
			phaseShifter.connect(connectTo());
			phaseShifter.offset90.connect(connectTo());
			phaseShifter.dispose();
		});

		it("passes the incoming signal through", () => {
			return PassAudio((input) => {
				const phaseShifter = new PhaseShiftAllpass().toDestination();
				input.connect(phaseShifter);
			});
		});

		it("generates correct values with the phase shifted channel", () => {
			return CompareToFile((context) => {
				// create impulse with 5 samples offset
				const constantNode = context.createConstantSource();
				constantNode.start(0);
				const oneSampleDelay = context.createIIRFilter([0.0, 1.0], [1.0, 0.0]);
				const fiveSampleDelay = context.createIIRFilter([0.0, 0.0, 0.0, 0.0, 0.0, 1.0], [1.0, 0.0, 0.0, 0.0, 0.0, 0.0]);
				const sub = new Subtract();

				connect(constantNode, oneSampleDelay);
				connect(constantNode, sub);
				connect(oneSampleDelay, sub.subtrahend);
				connect(sub, fiveSampleDelay);

				const phaseShifter = new PhaseShiftAllpass();
				connect(fiveSampleDelay, phaseShifter);
				phaseShifter.toDestination();

			}, "phaseShiftAllpass.wav", 0.001);
		});

		it("generates correct values with the offset90 channel", () => {
			return CompareToFile((context) => {
				// create impulse with 5 samples offset
				const constantNode = context.createConstantSource();
				constantNode.start(0);
				const oneSampleDelay = context.createIIRFilter([0.0, 1.0], [1.0, 0.0]);
				const fiveSampleDelay = context.createIIRFilter([0.0, 0.0, 0.0, 0.0, 0.0, 1.0], [1.0, 0.0, 0.0, 0.0, 0.0, 0.0]);
				const sub = new Subtract();

				connect(constantNode, oneSampleDelay);
				connect(constantNode, sub);
				connect(oneSampleDelay, sub.subtrahend);
				connect(sub, fiveSampleDelay);

				const phaseShifter = new PhaseShiftAllpass();
				connect(fiveSampleDelay, phaseShifter);
				phaseShifter.offset90.toDestination();

			}, "phaseShiftAllpass1.wav", 0.001);
		});
	});
});