// SonicForge VSTi Autosample Service
// Live playback 100% client-side (không Carla): VSTi note → SF2 autosampled
// (backend pedalboard, render 1 lần / plugin+preset) → FluidSynth WASM qua
// masterBus → mastering → main out. ensure() dedup in-flight request + cooldown
// lỗi (404/501/no pedalboard) để không spam server.
window.SonicVstiAutosample = window.SonicVstiAutosample || {};

(function () {
    var LS_MAP_KEY = 'sf_vsti_autosample_map';
    var LS_FAIL_KEY = 'sf_vsti_autosample_fail';
    var FAIL_COOLDOWN_MS = 60000;

    function readMap() {
        try { return JSON.parse(localStorage.getItem(LS_MAP_KEY) || '{}') || {}; } catch (e) { return {}; }
    }
    function writeMap(map) {
        try { localStorage.setItem(LS_MAP_KEY, JSON.stringify(map)); } catch (e) {}
    }
    function readFails() {
        try { return JSON.parse(localStorage.getItem(LS_FAIL_KEY) || '{}') || {}; } catch (e) { return {}; }
    }

    // Key = plugin + preset → autosample lại khi đổi preset (âm preset mới).
    function keyFor(synthEngine) {
        if (!synthEngine) return '';
        return String(synthEngine.plugin_id || '') + '|' + String(synthEngine.preset_id || synthEngine.presetId || '');
    }

    // SF id đã autosample cho engine (cache localStorage) — đồng bộ, không request.
    function sfIdFor(synthEngine) {
        var k = keyFor(synthEngine);
        if (!k) return null;
        var map = readMap();
        return (map[k] && map[k].sf_id) ? map[k].sf_id : null;
    }

    function entryFor(synthEngine) {
        var k = keyFor(synthEngine);
        if (!k) return null;
        return readMap()[k] || null;
    }

    var _inFlight = {}; // key → Promise<sf_id|null> — nhiều note cùng lúc chỉ 1 request

    // Đảm bảo SF2 autosampled tồn tại. Trả Promise<sf_id|null>; null =
    // không autosample được → caller fallback (oscillator / không phát).
    function ensure(synthEngine) {
        var k = keyFor(synthEngine);
        if (!k) return Promise.resolve(null);
        var cached = sfIdFor(synthEngine);
        if (cached) return Promise.resolve(cached);
        if (_inFlight[k]) return _inFlight[k];
        var fails = readFails();
        if (fails[k] && (Date.now() - fails[k]) < FAIL_COOLDOWN_MS) {
            return Promise.resolve(null);
        }
        if (!window.SonicAPI || !window.SonicAPI.autosampleVsti) {
            return Promise.resolve(null);
        }
        _inFlight[k] = new Promise(function (resolve) {
            var payload = {
                instrument_id: synthEngine.plugin_id,
                preset_id: synthEngine.preset_id || synthEngine.presetId || null,
                preset_path: synthEngine.preset_path || null,
                preset_data: synthEngine.preset_data || null
            };
            window.SonicAPI.autosampleVsti(payload).then(function (res) {
                delete _inFlight[k];
                if (res && res.success && res.sf_id) {
                    var map = readMap();
                    map[k] = { sf_id: res.sf_id, size_bytes: res.size_bytes || 0, note_count: res.note_count || 0, plugin_id: synthEngine.plugin_id, preset_id: synthEngine.preset_id || synthEngine.presetId || '', ts: Date.now() };
                    writeMap(map);
                    resolve(res.sf_id);
                } else {
                    resolve(null);
                }
            }).catch(function () {
                delete _inFlight[k];
                var fails2 = readFails();
                fails2[k] = Date.now();
                try { localStorage.setItem(LS_FAIL_KEY, JSON.stringify(fails2)); } catch (e) {}
                resolve(null);
            });
        });
        return _inFlight[k];
    }

    // Xoá cache + cooldown — cho phép re-sample (đổi preset/plugin hoặc debug).
    function clearCache() {
        try { localStorage.removeItem(LS_MAP_KEY); } catch (e) {}
        try { localStorage.removeItem(LS_FAIL_KEY); } catch (e) {}
    }

    window.SonicVstiAutosample = {
        keyFor: keyFor,
        sfIdFor: sfIdFor,
        entryFor: entryFor,
        ensure: ensure,
        clearCache: clearCache
    };
})();