// SonicForge TrackInstrument Service
// Bọc FluidSynth channel per-track: playNote/noteOff theo TrackInstrumentCtx
// (ch/program/synthEngine/sfId/bank/prog/dest) — dùng cho preview mọi nguồn
// (keybed, piano roll, draw, hardware MIDI, click) qua UnifiedMidiRouter.
// Tạo mới mỗi note-on (overwrite registry) — voice cũ giữ engine cũ trong
// tracker nên note-off luôn stop đúng channel.
window.TrackInstrument = window.TrackInstrument || {};

(function () {
    function TrackInstrument(trackId, ctx) {
        this.trackId = trackId;
        this.ch = ctx ? (ctx.ch != null ? ctx.ch : 0) : 0;
        this.program = ctx ? ctx.program : undefined;
        this.synthEngine = ctx ? ctx.synthEngine : undefined;
        this.sfId = ctx ? ctx.sfId : undefined;
        this.bank = ctx ? (ctx.bank || 0) : 0;
        this.prog = ctx ? (ctx.prog || 0) : 0;
        this.dest = ctx ? (ctx.dest || null) : null;
    }

    // Đảm bảo channel đã select đúng instrument trước khi play (fire-and-forget:
    // playNote tự load + retry nếu SF chưa load xong — dedup trong loadSoundFont).
    TrackInstrument.prototype._ensure = function () {
        try {
            if (!window.SonicSF || !window.SonicSF.selectInstrument) return;
            if (this.sfId) {
                window.SonicSF.selectInstrument(this.ch, this.bank, this.prog, this.sfId);
            } else if (this.program !== undefined) {
                window.SonicSF.selectInstrument(this.ch, 0, this.program, null);
            }
        } catch (e) {
            console.warn('[TrackInstrument] selectInstrument error:', e);
        }
    };

    TrackInstrument.prototype.playNote = function (pitch, velocity, durationMs, startTime) {
        try {
            if (!window.SonicSF || !window.SonicSF.playNote) return;
            this._ensure();
            var dur = (durationMs != null ? durationMs : 500) || 500;
            window.SonicSF.playNote(pitch, velocity != null ? velocity : 0.8, dur, startTime, this.program, this.dest, this.ch, this.synthEngine);
        } catch (e) {
            console.warn('[TrackInstrument] playNote error:', e);
        }
    };

    TrackInstrument.prototype.noteOff = function (pitch) {
        try {
            if (window.SonicSF && window.SonicSF.stopNote) window.SonicSF.stopNote(this.ch, pitch);
        } catch (e) {}
    };

    window.TrackInstrument = TrackInstrument;
})();