Function parseJSONStream

frontend/src/hooks/stream/useStreamingJSONParser.ts:174–303

(
    stream: ReadableStream<Uint8Array>,
    options: {
      onChunkParsed?: (chunk: any[], isFirstChunk: boolean) => void;
      onProgress?: (progress: number, stats: StreamingJSONParseStats) => void;
      onComplete?: (result: DataParseResult) => void;
      estimatedTotalBytes?: number;
      sampleLimit?: number;
    } = {}
  )

   * to be parsed in most cases. For very large files, we'll implement progressive loading.
   */
  const parseJSONStream = async (
    stream: ReadableStream<Uint8Array>,
    options: {
      onChunkParsed?: (chunk: any[], isFirstChunk: boolean) => void;
      onProgress?: (progress: number, stats: StreamingJSONParseStats) => void;
      onComplete?: (result: DataParseResult) => void;
      estimatedTotalBytes?: number;
      sampleLimit?: number;
    } = {}
  ): Promise<DataParseResult> => {
    const { 
      onChunkParsed, 
      onProgress, 
      onComplete,
      estimatedTotalBytes,
      sampleLimit = 1000
    } = options;
    
    try {
      setIsLoading(true);
      setError(null);
      setProgress(0);
      
      // Create StreamReader for efficient processing
      const streamReader = new StreamReader(stream);
      
      // Initialize statistics
      const stats: StreamingJSONParseStats = {
        bytesProcessed: 0,
        itemsProcessed: 0,
        chunksProcessed: 0,
        totalBytes: estimatedTotalBytes,
        isNested: false
      };
      
      // JSON parsing requires the entire content in most cases
      // For very large files, we'll implement a streaming JSON parser in future versions
      // For now, we'll read the entire file but in chunks for progress reporting
      
      let jsonText = '';
      
      // Read file in chunks for progress tracking
      await streamReader.readByChunks(chunk => {
        const text = new TextDecoder().decode(chunk, { stream: true });
        jsonText += text;
        
        // Update progress
        stats.bytesProcessed = streamReader.getBytesProcessed();
        stats.chunksProcessed++;
        
        setParseStats({ ...stats });
        
        // Calculate progress percentage
        const progressValue = estimatedTotalBytes 
          ? stats.bytesProcessed / estimatedTotalBytes
          : 0;
        
        setProgress(progressValue);