suaveplan/packages/media/audio-fx/audio-fx-plugin-spessasynth/tests/automation.test.ts

import type { BlockContext, ProcessorConfig } from "@suaveplan/audio-core";
import type {
    ChainContext,
    ChainHandle,
} from "@suaveplan/audio-fx-plugin-base/base";
import { defaultAmbientState } from "@suaveplan/audio-fx-plugin-base/chain";
import { describe, expect, it } from "@suaveplan/testing/runner";
import { SpessaSynthPlugin } from "../src/plugin/spessasynth-plugin.js";
import { buildFakeSf2Bytes, makeStubModule } from "./stub-module.js";

const SR = 48_000;
const BLOCK = 64;

function newCtx(): ChainContext {
    const chain: ChainHandle = {
        id: "auto",
        name: "auto",
        channels: 2,
        sampleRate: SR,
        blockSize: BLOCK,
        slotCount: 1,
    };
    return {
        chain,
        position: { index: 0, total: 1 },
        predecessors: [],
        successors: [],
        ambient: defaultAmbientState(),
        buses: { get: () => undefined, list: () => [] },
    };
}

describe("automation: master gain ramp affects rendered output", () => {
    it("master gain set to 0 produces silence; set to 2 produces louder output", {
        timeout: 5_000,
    }, async () => {
        const mod = makeStubModule();
        const plugin = new SpessaSynthPlugin({
            moduleLoader: async () => mod,
        });
        await plugin.init({
            soundFontBytes: buildFakeSf2Bytes(64),
            sampleRate: SR,
        });
        const config: ProcessorConfig = {
            sampleRate: SR,
            channels: 2,
            blockSize: BLOCK,
        };
        await plugin.setup(config, newCtx());

        plugin.sendMidi({
            type: "noteOn",
            channel: 0,
            note: 60,
            velocity: 100,
        });

        const ctx: BlockContext = {
            blockOffsetSamples: 0,
            sampleRate: SR,
            channels: 2,
            opts: {},
        };

        // Render with master gain 1 (default).
        const outBaseline: Float32Array[] = [
            new Float32Array(BLOCK),
            new Float32Array(BLOCK),
        ];
        plugin.process([], outBaseline, ctx);
        let baselineRms = 0;
        for (let i = 0; i < BLOCK; i++) baselineRms += outBaseline[0]![i]! ** 2;
        baselineRms = Math.sqrt(baselineRms / BLOCK);
        expect(baselineRms).toBeGreaterThan(0);

        // Silence: master 0.
        plugin.setParameter("master/gain", 0);
        const outSilent: Float32Array[] = [
            new Float32Array(BLOCK),
            new Float32Array(BLOCK),
        ];
        plugin.process([], outSilent, ctx);
        let silentRms = 0;
        for (let i = 0; i < BLOCK; i++) {
            silentRms += outSilent[0]![i]! ** 2;
        }
        expect(silentRms).toBe(0);

        // Loud: master 2.
        plugin.setParameter("master/gain", 2);
        const outLoud: Float32Array[] = [
            new Float32Array(BLOCK),
            new Float32Array(BLOCK),
        ];
        plugin.process([], outLoud, ctx);
        let loudRms = 0;
        for (let i = 0; i < BLOCK; i++) loudRms += outLoud[0]![i]! ** 2;
        loudRms = Math.sqrt(loudRms / BLOCK);
        // Should be roughly 2× the baseline.
        expect(loudRms).toBeGreaterThan(baselineRms);
    });

    it("channel volume parameter flushes to CC#7 each block", {
        timeout: 5_000,
    }, async () => {
        const mod = makeStubModule();
        const plugin = new SpessaSynthPlugin({
            moduleLoader: async () => mod,
        });
        await plugin.init({
            soundFontBytes: buildFakeSf2Bytes(64),
            sampleRate: SR,
        });
        await plugin.setup(
            { sampleRate: SR, channels: 2, blockSize: BLOCK },
            newCtx()
        );
        plugin.setParameter("channel/0/volume", 1);
        const out: Float32Array[] = [
            new Float32Array(BLOCK),
            new Float32Array(BLOCK),
        ];
        plugin.process([], out, {
            blockOffsetSamples: 0,
            sampleRate: SR,
            channels: 2,
            opts: {},
        });
        plugin.setParameter("channel/0/volume", 0);
        plugin.process([], out, {
            blockOffsetSamples: 0,
            sampleRate: SR,
            channels: 2,
            opts: {},
        });
        const proc = (
            mod as {
                lastProcessor?: {
                    observer: {
                        cc: Array<{
                            channel: number;
                            controller: number;
                            value: number;
                        }>;
                    };
                };
            }
        ).lastProcessor!;
        const ch0Vol = proc.observer.cc.filter(
            (e) => e.channel === 0 && e.controller === 7
        );
        // First flush wrote 127 (volume=1), second wrote 0.
        expect(ch0Vol[0]?.value).toBe(127);
        expect(ch0Vol[ch0Vol.length - 1]?.value).toBe(0);
    });
});