reasampler/tests/test_deck_groups.cpp

// Standalone tests for reasampler::instrument::ui::deck_groups — no VST3, no REAPER, no
// framework. knob_deck's own tests pin how a descriptor list LAYS OUT; these pin WHICH
// descriptors the Sample face carries: the signal-flow group order (pitch -> filter -> amp),
// the Filter group's contents, the wrapped deck height at the editor's two pinned widths, the
// hit-test reaching the new filter controls, and the bipolar knob law's inverse pair.

#include "../src/core/instrument/ui/deck_groups.h"

#include <cmath>
#include <cstdio>
#include <vector>

using namespace reasampler;
using namespace reasampler::instrument::ui;

static int g_fail = 0;
#define CHECK(cond) do { if(!(cond)) { \
    std::printf("FAIL line %d: %s\n", __LINE__, #cond); ++g_fail; } } while(0)

// The editor's two pinned client widths (checkSizeConstraint's 560 floor, the 840 default),
// less the band allocator's kPad inset on each side.
static constexpr int kAvailAtMinWidth = 560 - 16;
static constexpr int kAvailAtDefaultWidth = 840 - 16;

static int indexOfGroup(const std::vector<DeckGroupDesc>& g, int id) {
    for (std::size_t i = 0; i < g.size(); ++i) {
        if (g[i].id == id) return static_cast<int>(i);
    }
    return -1;
}

static int cell(DeckParam p) { return static_cast<int>(p); }

static void testDeckReadsPitchThenFilterThenAmpLeftToRight() {
    for (PlayMode mode : {PlayMode::Gate, PlayMode::Trigger}) {
        const std::vector<DeckGroupDesc> g = sampleDeckGroups(mode);
        const int pitch  = indexOfGroup(g, kGroupPitch);
        const int penv   = indexOfGroup(g, kGroupPitchEnv);
        const int filt   = indexOfGroup(g, kGroupFilter);
        const int fenv   = indexOfGroup(g, kGroupFilterEnv);
        const int amp    = indexOfGroup(g, kGroupAmpEnv);
        CHECK(pitch >= 0 && penv >= 0 && filt >= 0 && fenv >= 0 && amp >= 0);
        // The signal flow, left to right. Each envelope group trails its own stage.
        CHECK(pitch < penv);
        CHECK(penv < filt);
        CHECK(filt < fenv);
        CHECK(fenv < amp);
        // The two instance-wide groups stay at the end.
        CHECK(amp < indexOfGroup(g, kGroupVoice));
        CHECK(indexOfGroup(g, kGroupVoice) < indexOfGroup(g, kGroupMaster));
    }
}

static void testFilterGroupCarriesItsFiveToneControlsPlusModulation() {
    const std::vector<DeckGroupDesc>& g = sampleDeckGroups(PlayMode::Gate);
    const DeckGroupDesc& f = g[static_cast<std::size_t>(indexOfGroup(g, kGroupFilter))];
    const std::vector<int> expected = {
        cell(DeckParam::kFilterMorph),  cell(DeckParam::kFilterCutoff),
        cell(DeckParam::kFilterQ),      cell(DeckParam::kFilterDrive),
        cell(DeckParam::kFilterModAmt), cell(DeckParam::kFilterVel),
        cell(DeckParam::kFilterKeyTrack)};
    CHECK(f.cellIds == expected);
    // Off by default is a state question, but reachability is a layout one: the enable
    // toggle is in the caption row and the morph law in the knob row.
    CHECK(f.captionToggle.id == cell(DeckParam::kFilterEnable));
    CHECK(f.rowToggle.id == cell(DeckParam::kFilterLaw));

    const DeckGroupDesc& fe = g[static_cast<std::size_t>(indexOfGroup(g, kGroupFilterEnv))];
    const std::vector<int> env = {
        cell(DeckParam::kFilterEnvAttack), cell(DeckParam::kFilterEnvHold),
        cell(DeckParam::kFilterEnvDecay),  cell(DeckParam::kFilterEnvSustain),
        cell(DeckParam::kFilterEnvRelease)};
    CHECK(fe.cellIds == env);
    // The filter envelope has no enable of its own — the FILTER group's toggle governs both.
    CHECK(fe.captionToggle.id == -1);
    CHECK(fe.rowToggle.id == -1);
}

static void testAmpGroupWidthSurvivesAGateTriggerFlip() {
    // The reserved blanks are what stop a mode flip reflowing the groups beside AMP.
    const std::vector<DeckGroupDesc> gate = sampleDeckGroups(PlayMode::Gate);
    const std::vector<DeckGroupDesc> trig = sampleDeckGroups(PlayMode::Trigger);
    const DeckGroupDesc& a = gate[static_cast<std::size_t>(indexOfGroup(gate, kGroupAmpEnv))];
    const DeckGroupDesc& b = trig[static_cast<std::size_t>(indexOfGroup(trig, kGroupAmpEnv))];
    CHECK(deckGroupWidth(a) == deckGroupWidth(b));
    CHECK(a.cellIds.size() == b.cellIds.size());
    CHECK(b.cellIds[3] == -1 && b.cellIds[4] == -1);
    // Every other group is mode-independent, so the whole deck's height is too.
    CHECK(deckHeight(gate, kAvailAtDefaultWidth) == deckHeight(trig, kAvailAtDefaultWidth));
    CHECK(deckHeight(gate, kAvailAtMinWidth) == deckHeight(trig, kAvailAtMinWidth));
}

static void testWrappedDeckHeightAtThePinnedEditorWidths() {
    const std::vector<DeckGroupDesc> g = sampleDeckGroups(PlayMode::Gate);
    // At the default 840 the deck takes two rows: PITCH + PITCH ENV + FILTER fill the first,
    // the remaining four fit the second.
    CHECK(deckRowCount(g, kAvailAtDefaultWidth) == 2);
    CHECK(deckHeight(g, kAvailAtDefaultWidth) == 2 * kDeckGroupH + kDeckRowGap);
    // At the 560 floor it takes four; FILTER is wider than the row on its own.
    CHECK(deckRowCount(g, kAvailAtMinWidth) == 4);
    CHECK(deckHeight(g, kAvailAtMinWidth) == 4 * kDeckGroupH + 3 * kDeckRowGap);

    // Whole groups only, never split: every group's box lies inside the available width or is
    // the first of its row.
    const DeckLayout dl = layoutDeck(g, 8, 0, kAvailAtDefaultWidth);
    CHECK(dl.groups.size() == g.size());
    for (const DeckGroupLayout& gl : dl.groups) {
        CHECK(gl.box.x >= 8);
        CHECK(gl.box.height == kDeckGroupH);
    }
}

static void testHitTestResolvesTheNewFilterControls() {
    const std::vector<DeckGroupDesc> g = sampleDeckGroups(PlayMode::Gate);
    const DeckLayout dl = layoutDeck(g, 8, 40, kAvailAtDefaultWidth);
    const DeckGroupLayout& f =
        dl.groups[static_cast<std::size_t>(indexOfGroup(g, kGroupFilter))];

    // Every knob cell resolves to its own id, from the centre of its cell.
    for (const DeckCellLayout& c : f.cells) {
        const DeckHit hit = hitTestDeck(dl, c.cell.x + c.cell.width / 2,
                                        c.cell.y + c.cell.height / 2);
        CHECK(hit.kind == DeckHitKind::Knob);
        CHECK(hit.id == c.id);
    }
    CHECK(f.cells.size() == 7);
    CHECK(f.cells[1].id == cell(DeckParam::kFilterCutoff));

    // The enable toggle's two segments and the morph-law row toggle's two.
    const DeckHit off = hitTestDeck(dl, f.captionToggle.seg0.x + 2,
                                    f.captionToggle.seg0.y + 2);
    CHECK(off.kind == DeckHitKind::CaptionToggle);
    CHECK(off.id == cell(DeckParam::kFilterEnable) && off.segment == 0);
    const DeckHit on = hitTestDeck(dl, f.captionToggle.seg1.x + 2,
                                   f.captionToggle.seg1.y + 2);
    CHECK(on.id == cell(DeckParam::kFilterEnable) && on.segment == 1);

    const DeckHit band = hitTestDeck(dl, f.rowToggle.seg0.x + 2, f.rowToggle.seg0.y + 2);
    CHECK(band.kind == DeckHitKind::RowToggle);
    CHECK(band.id == cell(DeckParam::kFilterLaw) && band.segment == 0);
    const DeckHit notch = hitTestDeck(dl, f.rowToggle.seg1.x + 2, f.rowToggle.seg1.y + 2);
    CHECK(notch.id == cell(DeckParam::kFilterLaw) && notch.segment == 1);

    // The filter-envelope knobs resolve too, and are distinct ids from the amp's.
    const DeckGroupLayout& fe =
        dl.groups[static_cast<std::size_t>(indexOfGroup(g, kGroupFilterEnv))];
    const DeckHit attack = hitTestDeck(dl, fe.cells[0].cell.x + 4, fe.cells[0].cell.y + 4);
    CHECK(attack.kind == DeckHitKind::Knob);
    CHECK(attack.id == cell(DeckParam::kFilterEnvAttack));
    CHECK(attack.id != cell(DeckParam::kAttack));
}

static void testBipolarKnobLawRoundTripsAndIsExactAtCentre() {
    // Centre is EXACT in both directions: a knob parked at 0.5 stores 0, and 0 reads back
    // 0.5 — no residual modulation from a rounding hair.
    CHECK(deckBipolarFromNorm(0.5) == 0.0);
    CHECK(deckNormFromBipolar(0.0) == 0.5);
    CHECK(deckBipolarFromNorm(0.0) == -1.0);
    CHECK(deckBipolarFromNorm(1.0) == 1.0);
    for (int i = 0; i <= 200; ++i) {
        const double norm = static_cast<double>(i) / 200.0;
        CHECK(std::fabs(deckNormFromBipolar(deckBipolarFromNorm(norm)) - norm) < 1e-12);
        const double value = -1.0 + static_cast<double>(i) / 100.0;
        CHECK(std::fabs(deckBipolarFromNorm(deckNormFromBipolar(value)) - value) < 1e-12);
    }
    // Out of range clamps rather than extrapolating.
    CHECK(deckBipolarFromNorm(-3.0) == -1.0);
    CHECK(deckBipolarFromNorm(3.0) == 1.0);
    CHECK(deckNormFromBipolar(-3.0) == 0.0);
    CHECK(deckNormFromBipolar(3.0) == 1.0);
}

int main() {
    testDeckReadsPitchThenFilterThenAmpLeftToRight();
    testFilterGroupCarriesItsFiveToneControlsPlusModulation();
    testAmpGroupWidthSurvivesAGateTriggerFlip();
    testWrappedDeckHeightAtThePinnedEditorWidths();
    testHitTestResolvesTheNewFilterControls();
    testBipolarKnobLawRoundTripsAndIsExactAtCentre();
    if (g_fail == 0) std::printf("deck_groups: all tests passed\n");
    return g_fail == 0 ? 0 : 1;
}