Merge pS-w1-t3-state: persist preview-trigger velocity as ComponentState v6 (S-VIEW-4 core)

tests/test_sample_map.cpp

@@ -1026,6 +1026,85 @@ static void testComponentStateV5TruncatedMarker() {
     CHECK(back.selectionId.empty() && back.map.zones.empty());
 }
 
+// --- v6 component state: the S-VIEW-4 preview-trigger velocity ------------------
+
+static void testComponentStatePreviewVelocityRoundTrip() {
+    // The preview velocity round-trips through the v6 envelope alongside selection + mode + marker
+    // + zones. A non-default value (not 64) proves the byte is actually read back, not defaulted.
+    ComponentState s;
+    s.selectionId = "pick";
+    s.channelMode = ChannelMode::Stereo;
+    s.lastConsumedAssignGeneration = 1700000123456LL;
+    s.previewVelocity = 111;                                    // non-default
+    s.map.zones.push_back(zone("z0", 0, 127, /*override=*/std::nullopt));
+    const ComponentState back = deserializeComponentState(serializeComponentState(s), 44100.0);
+    CHECK(back.previewVelocity == 111);                         // velocity survives
+    CHECK(back.channelMode == ChannelMode::Stereo);             // envelope neighbours intact
+    CHECK(back.lastConsumedAssignGeneration == 1700000123456LL);
+    CHECK(back.selectionId == "pick");
+    CHECK(back.map.zones.size() == 1 && back.map.zones[0].sampleId == "z0");
+}
+
+static void testComponentStateDefaultPreviewVelocityIsMid() {
+    // A default-constructed state carries the mid velocity default and round-trips it.
+    const ComponentState back = deserializeComponentState(serializeComponentState(ComponentState{}), 44100.0);
+    CHECK(back.previewVelocity == kPreviewVelocityDefault);
+    CHECK(kPreviewVelocityDefault == 64);
+}
+
+static void testComponentStatePreviewVelocityExtremes() {
+    // The full MIDI velocity range round-trips: 1 (softest audible) and 127 (max) both survive the
+    // single-byte field without clamping or overflow.
+    for (std::uint8_t v : {std::uint8_t{1}, std::uint8_t{127}}) {
+        ComponentState s;
+        s.previewVelocity = v;
+        const ComponentState back = deserializeComponentState(serializeComponentState(s), 44100.0);
+        CHECK(back.previewVelocity == v);
+    }
+}
+
+static void testComponentStateV5LiftsVelocityToMid() {
+    // A GENUINE v5 blob (version tag 5: mode byte, 8-byte marker, then id + zones — NO velocity
+    // byte) must lift previewVelocity to kPreviewVelocityDefault, its mode/marker/selection/zones
+    // intact. Build it by hand (serializeComponentState now emits v6, so it cannot make a v5 blob).
+    // This proves an already-saved pre-S-VIEW-4 instance restores at the mid default.
+    std::vector<std::uint8_t> v5;
+    v5.push_back(5); v5.push_back(0); v5.push_back(0); v5.push_back(0);    // version 5
+    v5.push_back(1);                                                        // channel mode = stereo
+    for (int i = 0; i < 8; ++i) v5.push_back(0);                           // marker = 0
+    const std::string id = "saved";
+    v5.push_back(static_cast<std::uint8_t>(id.size())); v5.push_back(0); v5.push_back(0); v5.push_back(0);
+    v5.insert(v5.end(), id.begin(), id.end());
+    v5.push_back(0); v5.push_back(0); v5.push_back(0); v5.push_back(0);    // zone count 0
+    const ComponentState back = deserializeComponentState(v5, 44100.0);
+    CHECK(back.previewVelocity == kPreviewVelocityDefault);   // no velocity byte in v5 -> mid default
+    CHECK(back.channelMode == ChannelMode::Stereo);           // v5 mode byte honored
+    CHECK(back.selectionId == "saved");
+    CHECK(back.map.zones.empty());
+}
+
+static void testComponentStateV4LiftsVelocityToMid() {
+    // A pre-S8/S9 v4 blob (mode byte, then id + zones — no marker, no velocity) also lifts
+    // previewVelocity to the mid default. Proves the older-than-v5 lift path defaults the field too.
+    std::vector<std::uint8_t> v4;
+    v4.push_back(4); v4.push_back(0); v4.push_back(0); v4.push_back(0);    // version 4
+    v4.push_back(0);                                                        // channel mode = mono
+    v4.push_back(0); v4.push_back(0); v4.push_back(0); v4.push_back(0);    // id length 0
+    v4.push_back(0); v4.push_back(0); v4.push_back(0); v4.push_back(0);    // zone count 0
+    const ComponentState back = deserializeComponentState(v4, 44100.0);
+    CHECK(back.previewVelocity == kPreviewVelocityDefault);
+}
+
+static void testComponentStateV6TruncatedVelocity() {
+    // A v6 blob truncated inside the header before the velocity byte (mode + full marker present,
+    // velocity byte cut) -> empty, with the mid velocity default holding (bounded read, never throws).
+    std::vector<std::uint8_t> t{6, 0, 0, 0, 1};                            // version 6, mode byte
+    for (int i = 0; i < 8; ++i) t.push_back(0);                            // full marker, no velocity byte
+    const ComponentState back = deserializeComponentState(t, 44100.0);
+    CHECK(back.previewVelocity == kPreviewVelocityDefault);
+    CHECK(back.selectionId.empty() && back.map.zones.empty());
+}
+
 // --- MERGE COMPOSITION (S9 v5 marker envelope x S15/S16 v3 play-param payload) ----------------
 //
 // The merge of ps-w9-t1-sync (envelope v5, adds the consumed-assignment marker) and
@@ -1574,6 +1653,12 @@ int main() {
     testComponentStateDefaultMarkerIsZero();
     testComponentStateV4LiftsMarkerToZero();
     testComponentStateV5TruncatedMarker();
+    testComponentStatePreviewVelocityRoundTrip();
+    testComponentStateDefaultPreviewVelocityIsMid();
+    testComponentStatePreviewVelocityExtremes();
+    testComponentStateV5LiftsVelocityToMid();
+    testComponentStateV4LiftsVelocityToMid();
+    testComponentStateV6TruncatedVelocity();
     testV5EnvelopeWithMarkerAndPlayParamsRoundTrip();
     testV4BlobWithPlayParamsLiftsMarkerZeroKeepsPlay();