Class FormulaPostProcessorAsync

js/processing/formula_post_processor_async.js:12–468

* 异步公式后处理器 * 使用 Web Worker 在后台渲染 KaTeX 公式

     * 使用 Web Worker 在后台渲染 KaTeX 公式
     */
    class FormulaPostProcessorAsync {
        constructor() {
            this.worker = null;
            this.workerReady = false;
            this.pendingCallbacks = new Map();
            this.requestId = 0;
            this.initWorker();
        }

        /**
         * 初始化 Web Worker（使用 Blob URL 支持 file:// 协议）
         */
        initWorker() {
            try {
                // 创建内联 Worker 代码（Blob URL 方案，支持 file:// 协议）
                const workerCode = this.getWorkerCode();
                const blob = new Blob([workerCode], { type: 'application/javascript' });
                const workerUrl = URL.createObjectURL(blob);

                this.worker = new Worker(workerUrl);

                // 清理 Blob URL（Worker 已创建，不再需要）
                URL.revokeObjectURL(workerUrl);

                this.worker.onmessage = (e) => {
                    const { type } = e.data;

                    if (type === 'ready') {
                        this.workerReady = true;
                        console.log('[FormulaPostProcessorAsync] Worker ready (Blob URL)');
                        return;
                    }

                    if (type === 'batch_complete') {
                        const { batchId, results } = e.data;
                        const callback = this.pendingCallbacks.get(batchId);
                        if (callback) {
                            callback(results);
                            this.pendingCallbacks.delete(batchId);
                        }
                        return;
                    }

                    if (type === 'error') {
                        console.error('[FormulaPostProcessorAsync] Worker error:', e.data.error);
                        return;
                    }
                };

                this.worker.onerror = (error) => {
                    console.error('[FormulaPostProcessorAsync] Worker error:', error);
                    this.workerReady = false;
                };

            } catch (error) {
                console.warn('[FormulaPostProcessorAsync] Failed to create Worker, falling back to sync:', error);
                this.workerReady = false;
            }