G2.0: StateStore (JSON state file + atomic write)

2026-08-16 07:08:37 +07:00
parent af9a285974
commit 1fe2d261fd
4 changed files with 371 additions and 0 deletions
@@ -0,0 +1,44 @@
+// native_bridge/include/StateStore.h
+// G2: persist bridge instrument state to a JSON file so a bridge respawn
+// (crash, kill, restart) can reload instruments and continue playing.
+#ifndef STATE_STORE_H
+#define STATE_STORE_H
+
+#include <cstdint>
+#include <string>
+#include <vector>
+
+// One instrument slot persisted to disk.
+struct InstrumentStateEntry {
+    uint32_t channel = 0;
+    int type = 0;                 // InstrumentType as int (0=VST3, 1=VST2, 2=SF2/SF3, 3=SFZ)
+    std::string path;             // absolute plugin/soundfont path
+    std::string presetBase64;     // VST3 serialized preset (empty for non-VST)
+    uint32_t bank = 0;            // last bank select (SF2/SF3)
+    uint32_t program = 0;         // last program change
+};
+
+// Whole-bridge snapshot written to disk.
+struct BridgeStateSnapshot {
+    std::vector<InstrumentStateEntry> instruments;
+    bool playing = false;
+    double playhead = 0.0;
+};
+
+// Hand-rolled JSON persistence (no external JSON dependency).
+// File format: {"version":1,"playing":bool,"playhead":num,"instruments":[...]}
+// Writes are atomic: temp file + rename (crash mid-write never corrupts state).
+class StateStore {
+public:
+    // %APPDATA%/SonicForgeDAW/state/bridge_state.json (UTF-8).
+    static std::string defaultPath();
+
+    // Serialize snapshot to `path` (atomic). Returns false on IO error.
+    static bool save(const BridgeStateSnapshot& snap, const std::string& path);
+    // Read `path` into `out`; returns false if missing or unparsable.
+    static bool load(BridgeStateSnapshot& out, const std::string& path);
+    // Remove the state file (and any stale .tmp). Returns false if missing.
+    static bool clear(const std::string& path);
+};
+
+#endif // STATE_STORE_H