File Handling & Media Processing - 2/2

// Advanced large file handling system with streaming, chunking, and resumable uploads
class LargeFileStreamingManager {
  private streamingEngine: StreamingEngine;
  private chunkManager: ChunkManager;
  private resumeManager: ResumableUploadManager;
  private integrityChecker: FileIntegrityChecker;
  private compressionEngine: CompressionEngine;
  private deduplicationSystem: DeduplicationSystem;
  private rateLimiter: StreamingRateLimiter;

  constructor(config: LargeFileConfig) {
    this.streamingEngine = new StreamingEngine(config.streaming);
    this.chunkManager = new ChunkManager(config.chunking);
    this.resumeManager = new ResumableUploadManager(config.resume);
    this.integrityChecker = new FileIntegrityChecker();
    this.compressionEngine = new CompressionEngine(config.compression);
    this.deduplicationSystem = new DeduplicationSystem(config.deduplication);
    this.rateLimiter = new StreamingRateLimiter(config.rateLimit);

    this.setupStreamingWorkers();
    this.setupIntegrityMonitoring();
  }

  // Handle large file upload with streaming and resumability
  async uploadLargeFile(
    uploadRequest: LargeFileUploadRequest
  ): Promise<LargeFileUploadResult> {
    const uploadId = this.generateUploadId();
    const startTime = Date.now();

    try {
      console.log(
        `Starting large file upload: ${uploadId} (${uploadRequest.totalSize} bytes)`
      );

      // Check if file already exists (deduplication)
      const existingFile = await this.deduplicationSystem.findExisting(
        uploadRequest.fileHash
      );

      if (existingFile) {
        console.log(`File already exists, skipping upload: ${uploadId}`);
        return this.createDeduplicatedResult(existingFile, uploadId);
      }

      // Initialize resumable upload session
      const uploadSession = await this.resumeManager.createSession({
        uploadId,
        filename: uploadRequest.filename,
        totalSize: uploadRequest.totalSize,
        chunkSize:
          uploadRequest.chunkSize ||
          this.getOptimalChunkSize(uploadRequest.totalSize),
        fileHash: uploadRequest.fileHash,
        mimeType: uploadRequest.mimeType,
        userId: uploadRequest.userId,
      });

      // Stream and process chunks
      const processingResult = await this.processLargeFileStream(
        uploadRequest,
        uploadSession
      );

      // Finalize upload and verify integrity
      const finalResult = await this.finalizeUpload(
        uploadSession,
        processingResult,
        uploadRequest
      );

      console.log(`Large file upload completed: ${uploadId}`);
      return finalResult;
    } catch (error) {
      console.error(`Large file upload failed: ${uploadId}`, error);
      await this.cleanupFailedUpload(uploadId);
      throw new LargeFileError(
        "Large file upload failed",
        "UPLOAD_FAILED",
        500,
        { uploadId, originalError: error }
      );
    }
  }

  private async processLargeFileStream(
    request: LargeFileUploadRequest,
    session: UploadSession
  ): Promise<StreamProcessingResult> {
    const totalChunks = Math.ceil(request.totalSize / session.chunkSize);
    const processedChunks: ProcessedChunk[] = [];
    let uploadedBytes = 0;

    console.log(`Processing ${totalChunks} chunks for ${session.uploadId}`);

    // Create readable stream from request
    const fileStream = this.createFileStream(request);

    // Apply rate limiting
    const rateLimitedStream = this.rateLimiter.createLimitedStream(
      fileStream,
      request.userId
    );

    // Apply compression if beneficial
    const compressionResult = await this.compressionEngine.shouldCompress(
      request.mimeType,
      request.totalSize
    );

    let processedStream = rateLimitedStream;
    if (compressionResult.shouldCompress) {
      processedStream = this.compressionEngine.createCompressionStream(
        processedStream,
        compressionResult.algorithm
      );
    }

    // Process stream in chunks
    return new Promise((resolve, reject) => {
      let chunkIndex = 0;
      let buffer = Buffer.alloc(0);
      let totalProcessed = 0;

      processedStream.on("data", async (chunk: Buffer) => {
        try {
          buffer = Buffer.concat([buffer, chunk]);

          // Process complete chunks
          while (
            buffer.length >= session.chunkSize ||
            (chunkIndex === totalChunks - 1 && buffer.length > 0)
          ) {
            const chunkSize = Math.min(session.chunkSize, buffer.length);
            const chunkData = buffer.slice(0, chunkSize);
            buffer = buffer.slice(chunkSize);

            const processedChunk = await this.processChunk(
              chunkData,
              chunkIndex,
              session
            );

            processedChunks.push(processedChunk);
            totalProcessed += chunkSize;
            chunkIndex++;

            // Update progress
            await this.resumeManager.updateProgress(session.uploadId, {
              chunksCompleted: chunkIndex,
              totalChunks,
              bytesUploaded: totalProcessed,
            });

            // Call progress callback if provided
            if (request.onProgress) {
              request.onProgress({
                uploadId: session.uploadId,
                bytesUploaded: totalProcessed,
                totalBytes: request.totalSize,
                chunksCompleted: chunkIndex,
                totalChunks,
                percentage: (totalProcessed / request.totalSize) * 100,
              });
            }

            // Check if we've processed all chunks
            if (chunkIndex >= totalChunks) {
              resolve({
                chunks: processedChunks,
                totalSize: totalProcessed,
                compressionUsed: compressionResult.shouldCompress,
                compressionRatio: compressionResult.shouldCompress
                  ? totalProcessed / request.totalSize
                  : 1,
              });
              return;
            }
          }
        } catch (error) {
          reject(error);
        }
      });

      processedStream.on("error", reject);
      processedStream.on("end", () => {
        // Handle any remaining buffer data
        if (buffer.length > 0 && chunkIndex < totalChunks) {
          this.processChunk(buffer, chunkIndex, session)
            .then((processedChunk) => {
              processedChunks.push(processedChunk);
              resolve({
                chunks: processedChunks,
                totalSize: totalProcessed + buffer.length,
                compressionUsed: compressionResult.shouldCompress,
                compressionRatio: compressionResult.shouldCompress
                  ? (totalProcessed + buffer.length) / request.totalSize
                  : 1,
              });
            })
            .catch(reject);
        }
      });
    });
  }

  private async processChunk(
    chunkData: Buffer,
    chunkIndex: number,
    session: UploadSession
  ): Promise<ProcessedChunk> {
    console.log(`Processing chunk ${chunkIndex} for ${session.uploadId}`);

    // Calculate chunk hash for integrity verification
    const chunkHash = this.integrityChecker.calculateHash(chunkData);

    // Check if this chunk was already uploaded (resumable uploads)
    const existingChunk = await this.resumeManager.getChunk(
      session.uploadId,
      chunkIndex
    );

    if (existingChunk && existingChunk.hash === chunkHash) {
      console.log(`Chunk ${chunkIndex} already uploaded, skipping`);
      return existingChunk;
    }

    // Upload chunk to storage
    const storageResult = await this.chunkManager.uploadChunk({
      uploadId: session.uploadId,
      chunkIndex,
      data: chunkData,
      hash: chunkHash,
      size: chunkData.length,
    });

    // Store chunk metadata
    const processedChunk: ProcessedChunk = {
      index: chunkIndex,
      hash: chunkHash,
      size: chunkData.length,
      storageKey: storageResult.key,
      etag: storageResult.etag,
      uploadedAt: Date.now(),
    };

    await this.resumeManager.saveChunk(session.uploadId, processedChunk);

    return processedChunk;
  }

  // Resume interrupted upload
  async resumeUpload(uploadId: string): Promise<ResumeResult> {
    try {
      const session = await this.resumeManager.getSession(uploadId);
      if (!session) {
        throw new LargeFileError(
          "Upload session not found",
          "SESSION_NOT_FOUND",
          404
        );
      }

      // Check session expiration
      if (this.resumeManager.isSessionExpired(session)) {
        await this.resumeManager.cleanupSession(uploadId);
        throw new LargeFileError(
          "Upload session expired",
          "SESSION_EXPIRED",
          410
        );
      }

      // Get completed chunks
      const completedChunks = await this.resumeManager.getCompletedChunks(
        uploadId
      );
      const totalChunks = Math.ceil(session.totalSize / session.chunkSize);

      return {
        uploadId,
        completedChunks: completedChunks.map((c) => c.index),
        totalChunks,
        bytesCompleted: completedChunks.reduce((sum, c) => sum + c.size, 0),
        totalBytes: session.totalSize,
        nextChunkIndex:
          completedChunks.length > 0
            ? Math.max(...completedChunks.map((c) => c.index)) + 1
            : 0,
      };
    } catch (error) {
      console.error(`Resume upload failed: ${uploadId}`, error);
      throw error;
    }
  }

  // Stream large file for download with range support
  async streamFileDownload(
    request: FileDownloadRequest
  ): Promise<FileDownloadStream> {
    try {
      // Get file metadata
      const fileMetadata = await this.getFileMetadata(request.fileId);

      // Check permissions
      await this.verifyDownloadPermissions(request.userId, request.fileId);

      // Parse range header if present
      const range = this.parseRangeHeader(request.range, fileMetadata.size);

      // Create download stream
      const downloadStream = await this.createDownloadStream(
        fileMetadata,
        range
      );

      // Apply rate limiting for downloads
      const rateLimitedStream = this.rateLimiter.createDownloadStream(
        downloadStream,
        request.userId
      );

      // Decompress if needed
      let finalStream = rateLimitedStream;
      if (fileMetadata.compression) {
        finalStream = this.compressionEngine.createDecompressionStream(
          rateLimitedStream,
          fileMetadata.compression.algorithm
        );
      }

      return {
        stream: finalStream,
        size: range ? range.end - range.start + 1 : fileMetadata.size,
        contentType: fileMetadata.mimeType,
        range: range,
        headers: this.generateDownloadHeaders(fileMetadata, range),
      };
    } catch (error) {
      console.error(`File download failed: ${request.fileId}`, error);
      throw new LargeFileError("File download failed", "DOWNLOAD_FAILED", 500, {
        fileId: request.fileId,
        originalError: error,
      });
    }
  }

  private async createDownloadStream(
    fileMetadata: FileMetadata,
    range?: ByteRange
  ): Promise<NodeJS.ReadableStream> {
    if (fileMetadata.storage.type === "chunked") {
      // For chunked files, create stream from chunks
      return this.createChunkedDownloadStream(fileMetadata, range);
    } else {
      // For single files, use regular streaming
      return this.streamingEngine.createStream(
        fileMetadata.storage.location,
        range
      );
    }
  }

  private async createChunkedDownloadStream(
    fileMetadata: FileMetadata,
    range?: ByteRange
  ): Promise<NodeJS.ReadableStream> {
    const chunks = await this.chunkManager.getFileChunks(fileMetadata.fileId);

    // Calculate which chunks we need based on range
    const requiredChunks = range
      ? this.calculateChunksForRange(chunks, range)
      : chunks;

    return this.chunkManager.createChunkedStream(requiredChunks, range);
  }

  private calculateChunksForRange(
    chunks: ChunkInfo[],
    range: ByteRange
  ): ChunkInfo[] {
    const requiredChunks: ChunkInfo[] = [];
    let currentOffset = 0;

    for (const chunk of chunks.sort((a, b) => a.index - b.index)) {
      const chunkEnd = currentOffset + chunk.size - 1;

      // Check if this chunk overlaps with the requested range
      if (chunkEnd >= range.start && currentOffset <= range.end) {
        requiredChunks.push({
          ...chunk,
          rangeStart: Math.max(0, range.start - currentOffset),
          rangeEnd: Math.min(chunk.size - 1, range.end - currentOffset),
        });
      }

      currentOffset += chunk.size;

      // Stop if we've passed the requested range
      if (currentOffset > range.end) {
        break;
      }
    }

    return requiredChunks;
  }

  // Parallel download with multiple connections
  async downloadLargeFileParallel(
    request: ParallelDownloadRequest
  ): Promise<ParallelDownloadResult> {
    const fileMetadata = await this.getFileMetadata(request.fileId);
    const connections =
      request.connections || this.getOptimalConnectionCount(fileMetadata.size);
    const chunkSize = Math.ceil(fileMetadata.size / connections);

    console.log(
      `Starting parallel download: ${request.fileId} (${connections} connections)`
    );

    const downloadPromises: Promise<DownloadChunk>[] = [];

    for (let i = 0; i < connections; i++) {
      const start = i * chunkSize;
      const end = Math.min(start + chunkSize - 1, fileMetadata.size - 1);

      if (start <= end) {
        downloadPromises.push(
          this.downloadChunk(request.fileId, start, end, i, request.userId)
        );
      }
    }

    try {
      const chunks = await Promise.all(downloadPromises);

      // Combine chunks in order
      const combinedBuffer = this.combineDownloadChunks(chunks);

      // Verify integrity if hash is available
      if (fileMetadata.hash) {
        const downloadHash =
          this.integrityChecker.calculateHash(combinedBuffer);
        if (downloadHash !== fileMetadata.hash) {
          throw new LargeFileError(
            "Download integrity check failed",
            "INTEGRITY_CHECK_FAILED",
            500
          );
        }
      }

      return {
        fileId: request.fileId,
        data: combinedBuffer,
        size: combinedBuffer.length,
        downloadTime: Date.now() - Date.now(), // Would track actual time
        connectionsUsed: connections,
      };
    } catch (error) {
      console.error(`Parallel download failed: ${request.fileId}`, error);
      throw error;
    }
  }

  private async downloadChunk(
    fileId: string,
    start: number,
    end: number,
    chunkIndex: number,
    userId: string
  ): Promise<DownloadChunk> {
    const range = `bytes=${start}-${end}`;

    const downloadRequest: FileDownloadRequest = {
      fileId,
      userId,
      range,
    };

    const downloadStream = await this.streamFileDownload(downloadRequest);

    return new Promise((resolve, reject) => {
      const chunks: Buffer[] = [];

      downloadStream.stream.on("data", (chunk: Buffer) => {
        chunks.push(chunk);
      });

      downloadStream.stream.on("end", () => {
        resolve({
          index: chunkIndex,
          data: Buffer.concat(chunks),
          start,
          end,
        });
      });

      downloadStream.stream.on("error", reject);
    });
  }

  private combineDownloadChunks(chunks: DownloadChunk[]): Buffer {
    // Sort chunks by index to ensure correct order
    const sortedChunks = chunks.sort((a, b) => a.index - b.index);
    return Buffer.concat(sortedChunks.map((chunk) => chunk.data));
  }

  // Utility methods
  private getOptimalChunkSize(fileSize: number): number {
    // Optimize chunk size based on file size
    if (fileSize < 100 * 1024 * 1024) {
      // < 100MB
      return 5 * 1024 * 1024; // 5MB chunks
    } else if (fileSize < 1024 * 1024 * 1024) {
      // < 1GB
      return 10 * 1024 * 1024; // 10MB chunks
    } else if (fileSize < 10 * 1024 * 1024 * 1024) {
      // < 10GB
      return 50 * 1024 * 1024; // 50MB chunks
    } else {
      return 100 * 1024 * 1024; // 100MB chunks
    }
  }

  private getOptimalConnectionCount(fileSize: number): number {
    // Optimize connection count based on file size
    if (fileSize < 100 * 1024 * 1024) {
      // < 100MB
      return 2;
    } else if (fileSize < 1024 * 1024 * 1024) {
      // < 1GB
      return 4;
    } else {
      return 8;
    }
  }

  private parseRangeHeader(
    rangeHeader: string | undefined,
    fileSize: number
  ): ByteRange | null {
    if (!rangeHeader) return null;

    const match = rangeHeader.match(/^bytes=(\d+)-(\d*)$/);
    if (!match) return null;

    const start = parseInt(match[1]);
    const end = match[2] ? parseInt(match[2]) : fileSize - 1;

    return { start, end };
  }

  private generateDownloadHeaders(
    metadata: FileMetadata,
    range?: ByteRange
  ): Record<string, string> {
    const headers: Record<string, string> = {
      "Content-Type": metadata.mimeType,
      "Content-Length": range
        ? (range.end - range.start + 1).toString()
        : metadata.size.toString(),
      "Accept-Ranges": "bytes",
      "Cache-Control": "public, max-age=3600",
      ETag: metadata.etag || metadata.hash,
    };

    if (range) {
      headers[
        "Content-Range"
      ] = `bytes ${range.start}-${range.end}/${metadata.size}`;
      headers["Status"] = "206";
    }

    return headers;
  }

  private createFileStream(
    request: LargeFileUploadRequest
  ): NodeJS.ReadableStream {
    // Implementation would create stream from request data source
    throw new Error("createFileStream implementation needed");
  }

  private async getFileMetadata(fileId: string): Promise<FileMetadata> {
    // Implementation would retrieve file metadata
    throw new Error("getFileMetadata implementation needed");
  }

  private async verifyDownloadPermissions(
    userId: string,
    fileId: string
  ): Promise<void> {
    // Implementation would check download permissions
  }

  private generateUploadId(): string {
    return `large_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`;
  }

  private async finalizeUpload(
    session: UploadSession,
    processing: StreamProcessingResult,
    request: LargeFileUploadRequest
  ): Promise<LargeFileUploadResult> {
    // Implementation would finalize upload and create file record
    return {
      uploadId: session.uploadId,
      fileId: this.generateFileId(),
      filename: request.filename,
      size: processing.totalSize,
      url: `https://files.example.com/${session.uploadId}`,
      uploadedAt: Date.now(),
    };
  }

  private generateFileId(): string {
    return `file_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`;
  }

  private async createDeduplicatedResult(
    existingFile: any,
    uploadId: string
  ): Promise<LargeFileUploadResult> {
    return {
      uploadId,
      fileId: existingFile.fileId,
      filename: existingFile.filename,
      size: existingFile.size,
      url: existingFile.url,
      uploadedAt: Date.now(),
      deduplicated: true,
    };
  }

  private async cleanupFailedUpload(uploadId: string): Promise<void> {
    // Implementation would cleanup failed upload resources
  }

  private setupStreamingWorkers(): void {
    // Implementation would setup background workers
  }

  private setupIntegrityMonitoring(): void {
    // Implementation would setup integrity monitoring
  }
}

// Supporting classes and interfaces
interface LargeFileUploadRequest {
  filename: string;
  totalSize: number;
  chunkSize?: number;
  fileHash: string;
  mimeType: string;
  userId: string;
  onProgress?: (progress: UploadProgress) => void;
}

interface UploadSession {
  uploadId: string;
  filename: string;
  totalSize: number;
  chunkSize: number;
  fileHash: string;
  mimeType: string;
  userId: string;
  createdAt: number;
  expiresAt: number;
}

interface ProcessedChunk {
  index: number;
  hash: string;
  size: number;
  storageKey: string;
  etag: string;
  uploadedAt: number;
}

interface StreamProcessingResult {
  chunks: ProcessedChunk[];
  totalSize: number;
  compressionUsed: boolean;
  compressionRatio: number;
}

interface UploadProgress {
  uploadId: string;
  bytesUploaded: number;
  totalBytes: number;
  chunksCompleted: number;
  totalChunks: number;
  percentage: number;
}

interface FileDownloadRequest {
  fileId: string;
  userId: string;
  range?: string;
}

interface ByteRange {
  start: number;
  end: number;
}

interface FileDownloadStream {
  stream: NodeJS.ReadableStream;
  size: number;
  contentType: string;
  range?: ByteRange;
  headers: Record<string, string>;
}

interface ParallelDownloadRequest {
  fileId: string;
  userId: string;
  connections?: number;
}

interface DownloadChunk {
  index: number;
  data: Buffer;
  start: number;
  end: number;
}

interface ParallelDownloadResult {
  fileId: string;
  data: Buffer;
  size: number;
  downloadTime: number;
  connectionsUsed: number;
}

interface ChunkInfo {
  index: number;
  size: number;
  hash: string;
  storageKey: string;
  rangeStart?: number;
  rangeEnd?: number;
}

interface FileMetadata {
  fileId: string;
  filename: string;
  size: number;
  mimeType: string;
  hash: string;
  etag?: string;
  storage: {
    type: "single" | "chunked";
    location: string;
  };
  compression?: {
    algorithm: string;
    originalSize: number;
  };
}

interface LargeFileUploadResult {
  uploadId: string;
  fileId: string;
  filename: string;
  size: number;
  url: string;
  uploadedAt: number;
  deduplicated?: boolean;
}

interface ResumeResult {
  uploadId: string;
  completedChunks: number[];
  totalChunks: number;
  bytesCompleted: number;
  totalBytes: number;
  nextChunkIndex: number;
}

class LargeFileError extends Error {
  constructor(
    message: string,
    public code: string,
    public status: number,
    public metadata?: any
  ) {
    super(message);
    this.name = "LargeFileError";
  }
}

// Placeholder classes that would need full implementation
interface LargeFileConfig {
  streaming: any;
  chunking: any;
  resume: any;
  compression: any;
  deduplication: any;
  rateLimit: any;
}

class StreamingEngine {
  constructor(config: any) {}

  async createStream(
    location: string,
    range?: ByteRange
  ): Promise<NodeJS.ReadableStream> {
    // Implementation would create streaming interface
    throw new Error("createStream implementation needed");
  }
}

class ChunkManager {
  constructor(config: any) {}

  async uploadChunk(chunk: any): Promise<any> {
    return { key: "chunk-key", etag: "etag" };
  }

  async getFileChunks(fileId: string): Promise<ChunkInfo[]> {
    return [];
  }

  async createChunkedStream(
    chunks: ChunkInfo[],
    range?: ByteRange
  ): Promise<NodeJS.ReadableStream> {
    throw new Error("createChunkedStream implementation needed");
  }
}

class ResumableUploadManager {
  constructor(config: any) {}

  async createSession(options: any): Promise<UploadSession> {
    return options as UploadSession;
  }

  async getSession(uploadId: string): Promise<UploadSession | null> {
    return null;
  }

  async updateProgress(uploadId: string, progress: any): Promise<void> {}

  async getChunk(
    uploadId: string,
    chunkIndex: number
  ): Promise<ProcessedChunk | null> {
    return null;
  }

  async saveChunk(uploadId: string, chunk: ProcessedChunk): Promise<void> {}

  async getCompletedChunks(uploadId: string): Promise<ProcessedChunk[]> {
    return [];
  }

  isSessionExpired(session: UploadSession): boolean {
    return Date.now() > session.expiresAt;
  }

  async cleanupSession(uploadId: string): Promise<void> {}
}

class FileIntegrityChecker {
  calculateHash(data: Buffer): string {
    // Implementation would calculate file hash
    return "hash-placeholder";
  }
}

class CompressionEngine {
  constructor(config: any) {}

  async shouldCompress(
    mimeType: string,
    size: number
  ): Promise<{ shouldCompress: boolean; algorithm: string }> {
    return { shouldCompress: false, algorithm: "none" };
  }

  createCompressionStream(
    stream: NodeJS.ReadableStream,
    algorithm: string
  ): NodeJS.ReadableStream {
    return stream;
  }

  createDecompressionStream(
    stream: NodeJS.ReadableStream,
    algorithm: string
  ): NodeJS.ReadableStream {
    return stream;
  }
}

class DeduplicationSystem {
  constructor(config: any) {}

  async findExisting(hash: string): Promise<any> {
    return null;
  }
}

class StreamingRateLimiter {
  constructor(config: any) {}

  createLimitedStream(
    stream: NodeJS.ReadableStream,
    userId: string
  ): NodeJS.ReadableStream {
    return stream;
  }

  createDownloadStream(
    stream: NodeJS.ReadableStream,
    userId: string
  ): NodeJS.ReadableStream {
    return stream;
  }
}

// Advanced metadata extraction and management system
class MetadataManagementEngine {
  private extractors: Map<string, MetadataExtractor>;
  private metadataStore: MetadataStore;
  private indexer: MetadataIndexer;
  private searchEngine: MetadataSearchEngine;
  private versioning: MetadataVersioning;
  private auditLogger: MetadataAuditLogger;
  private scheduler: MetadataScheduler;

  constructor(config: MetadataConfig) {
    this.metadataStore = new MetadataStore(config.storage);
    this.indexer = new MetadataIndexer(config.indexing);
    this.searchEngine = new MetadataSearchEngine(config.search);
    this.versioning = new MetadataVersioning();
    this.auditLogger = new MetadataAuditLogger();
    this.scheduler = new MetadataScheduler();

    this.initializeExtractors();
    this.setupBackgroundProcessing();
  }

  // Extract comprehensive metadata from file
  async extractMetadata(
    fileId: string,
    filePath: string,
    mimeType: string,
    options: ExtractionOptions = {}
  ): Promise<ExtractedMetadata> {
    const extractionId = this.generateExtractionId();
    const startTime = Date.now();

    try {
      console.log(
        `Starting metadata extraction: ${extractionId} for ${fileId}`
      );

      // Get appropriate extractors for this file type
      const extractors = this.getExtractorsForMimeType(mimeType);

      // Extract metadata from all applicable extractors
      const extractionResults: ExtractionResult[] = [];

      for (const extractor of extractors) {
        try {
          console.log(
            `Running extractor: ${extractor.getName()} for ${fileId}`
          );

          const result = await extractor.extract(filePath, {
            ...options,
            fileId,
            mimeType,
          });

          extractionResults.push({
            extractorName: extractor.getName(),
            success: true,
            metadata: result,
            extractionTime: result.extractionTime || 0,
          });
        } catch (error) {
          console.error(
            `Extractor ${extractor.getName()} failed for ${fileId}:`,
            error
          );

          extractionResults.push({
            extractorName: extractor.getName(),
            success: false,
            error: error.message,
            extractionTime: 0,
          });
        }
      }

      // Combine and normalize metadata
      const combinedMetadata = this.combineExtractionResults(extractionResults);

      // Add system metadata
      const systemMetadata = await this.generateSystemMetadata(
        fileId,
        filePath
      );

      // Create final metadata object
      const finalMetadata: ExtractedMetadata = {
        fileId,
        extractionId,
        extractedAt: Date.now(),
        extractionTime: Date.now() - startTime,

        // Core metadata
        technical: combinedMetadata.technical,
        descriptive: combinedMetadata.descriptive,
        administrative: systemMetadata,

        // Format-specific metadata
        image: combinedMetadata.image,
        video: combinedMetadata.video,
        audio: combinedMetadata.audio,
        document: combinedMetadata.document,

        // Quality metrics
        extractionResults,
        qualityScore: this.calculateQualityScore(extractionResults),
      };

      // Store metadata with versioning
      await this.storeMetadata(finalMetadata);

      // Index for search
      await this.indexMetadata(finalMetadata);

      // Log extraction for audit
      await this.auditLogger.logExtraction(extractionId, finalMetadata);

      console.log(`Metadata extraction completed: ${extractionId}`);
      return finalMetadata;
    } catch (error) {
      console.error(`Metadata extraction failed: ${extractionId}`, error);
      throw new MetadataError(
        "Metadata extraction failed",
        "EXTRACTION_FAILED",
        500,
        { extractionId, fileId, originalError: error }
      );
    }
  }

  private combineExtractionResults(
    results: ExtractionResult[]
  ): CombinedMetadata {
    const combined: CombinedMetadata = {
      technical: {},
      descriptive: {},
      image: {},
      video: {},
      audio: {},
      document: {},
    };

    for (const result of results) {
      if (result.success && result.metadata) {
        // Merge metadata categories
        Object.keys(result.metadata).forEach((category) => {
          if (combined[category as keyof CombinedMetadata]) {
            Object.assign(
              combined[category as keyof CombinedMetadata],
              result.metadata[category]
            );
          }
        });
      }
    }

    return combined;
  }

  private async generateSystemMetadata(
    fileId: string,
    filePath: string
  ): Promise<AdministrativeMetadata> {
    const stats = await this.getFileStats(filePath);

    return {
      fileId,
      createdAt: Date.now(),
      modifiedAt: stats.mtime.getTime(),
      size: stats.size,
      checksum: await this.calculateChecksum(filePath),
      storage: {
        location: filePath,
        provider: "local", // Would be determined by storage configuration
        redundancy: "single",
      },
      processing: {
        extractedAt: Date.now(),
        version: "1.0",
      },
    };
  }

  // Advanced metadata search with faceted filtering
  async searchMetadata(
    query: MetadataSearchQuery
  ): Promise<MetadataSearchResult> {
    try {
      console.log(`Executing metadata search:`, query);

      // Build search parameters
      const searchParams = this.buildSearchParameters(query);

      // Execute search with faceting
      const searchResults = await this.searchEngine.search(searchParams);

      // Apply additional filters
      const filteredResults = await this.applyAdvancedFilters(
        searchResults,
        query.filters || {}
      );

      // Calculate facets for navigation
      const facets = await this.calculateSearchFacets(filteredResults, query);

      return {
        query,
        results: filteredResults,
        facets,
        totalResults: filteredResults.length,
        executionTime: Date.now() - Date.now(), // Would track actual time
        suggestions: await this.generateSearchSuggestions(query),
      };
    } catch (error) {
      console.error("Metadata search failed:", error);
      throw new MetadataError("Metadata search failed", "SEARCH_FAILED", 500, {
        query,
        originalError: error,
      });
    }
  }

  private buildSearchParameters(query: MetadataSearchQuery): SearchParameters {
    return {
      text: query.text,
      fields: query.fields || [
        "descriptive.title",
        "descriptive.description",
        "descriptive.keywords",
      ],
      filters: this.convertFiltersToSearchFilters(query.filters || {}),
      sort: query.sort || [{ field: "createdAt", direction: "desc" }],
      limit: query.limit || 20,
      offset: query.offset || 0,
      facets: query.includeFacets ? this.getAvailableFacets() : [],
    };
  }

  private async applyAdvancedFilters(
    results: any[],
    filters: MetadataFilters
  ): Promise<MetadataSearchItem[]> {
    let filteredResults = results;

    // Date range filters
    if (filters.dateRange) {
      filteredResults = filteredResults.filter((item) => {
        const createdAt = new Date(item.administrative.createdAt);
        return (
          createdAt >= filters.dateRange!.start &&
          createdAt <= filters.dateRange!.end
        );
      });
    }

    // Size filters
    if (filters.sizeRange) {
      filteredResults = filteredResults.filter((item) => {
        const size = item.administrative.size;
        return size >= filters.sizeRange!.min && size <= filters.sizeRange!.max;
      });
    }

    // Dimension filters for images/videos
    if (filters.dimensions) {
      filteredResults = filteredResults.filter((item) => {
        if (item.image) {
          return (
            item.image.width >= filters.dimensions!.minWidth &&
            item.image.height >= filters.dimensions!.minHeight
          );
        }
        if (item.video) {
          return (
            item.video.width >= filters.dimensions!.minWidth &&
            item.video.height >= filters.dimensions!.minHeight
          );
        }
        return true;
      });
    }

    // Duration filters for audio/video
    if (filters.durationRange) {
      filteredResults = filteredResults.filter((item) => {
        const duration = item.audio?.duration || item.video?.duration;
        return (
          duration &&
          duration >= filters.durationRange!.min &&
          duration <= filters.durationRange!.max
        );
      });
    }

    return filteredResults.map(this.transformToSearchItem);
  }

  private transformToSearchItem(item: any): MetadataSearchItem {
    return {
      fileId: item.fileId,
      filename: item.descriptive.filename,
      mimeType: item.technical.mimeType,
      size: item.administrative.size,
      createdAt: item.administrative.createdAt,
      thumbnail: item.image?.thumbnail || item.video?.thumbnail,
      score: item._score || 1,
      highlights: item._highlights || {},
    };
  }

  // Batch metadata processing
  async processBatchMetadata(
    files: BatchMetadataRequest[]
  ): Promise<BatchMetadataResult> {
    const batchId = this.generateBatchId();
    const startTime = Date.now();

    console.log(
      `Starting batch metadata processing: ${batchId} (${files.length} files)`
    );

    const results: MetadataProcessingResult[] = [];
    const errors: BatchMetadataError[] = [];

    // Process in chunks to avoid overwhelming the system
    const chunkSize = 10;
    for (let i = 0; i < files.length; i += chunkSize) {
      const chunk = files.slice(i, i + chunkSize);

      const chunkPromises = chunk.map(async (file, index) => {
        try {
          const metadata = await this.extractMetadata(
            file.fileId,
            file.filePath,
            file.mimeType,
            file.options
          );

          results.push({
            fileId: file.fileId,
            success: true,
            metadata,
            processingTime: metadata.extractionTime,
          });
        } catch (error) {
          errors.push({
            index: i + index,
            fileId: file.fileId,
            error: error.message,
            code: error.code,
          });
        }
      });

      await Promise.all(chunkPromises);

      // Add delay between chunks to prevent overwhelming
      if (i + chunkSize < files.length) {
        await new Promise((resolve) => setTimeout(resolve, 100));
      }
    }

    return {
      batchId,
      totalFiles: files.length,
      successfulProcessing: results.length,
      failedProcessing: errors.length,
      results,
      errors,
      processingTime: Date.now() - startTime,
      completedAt: Date.now(),
    };
  }

  // Metadata analytics and insights
  async generateMetadataAnalytics(
    criteria: AnalyticsCriteria
  ): Promise<MetadataAnalytics> {
    try {
      const analytics: MetadataAnalytics = {
        criteria,
        generatedAt: Date.now(),

        // File type distribution
        fileTypeDistribution: await this.calculateFileTypeDistribution(
          criteria
        ),

        // Size analytics
        sizeAnalytics: await this.calculateSizeAnalytics(criteria),

        // Temporal analytics
        temporalAnalytics: await this.calculateTemporalAnalytics(criteria),

        // Quality metrics
        qualityMetrics: await this.calculateQualityMetrics(criteria),

        // Format-specific analytics
        imageAnalytics: await this.calculateImageAnalytics(criteria),
        videoAnalytics: await this.calculateVideoAnalytics(criteria),
        audioAnalytics: await this.calculateAudioAnalytics(criteria),
        documentAnalytics: await this.calculateDocumentAnalytics(criteria),
      };

      return analytics;
    } catch (error) {
      console.error("Metadata analytics generation failed:", error);
      throw new MetadataError(
        "Analytics generation failed",
        "ANALYTICS_FAILED",
        500,
        { criteria, originalError: error }
      );
    }
  }

  // Metadata maintenance and optimization
  async optimizeMetadataStorage(): Promise<OptimizationResult> {
    const startTime = Date.now();

    console.log("Starting metadata storage optimization");

    const optimizationTasks = [
      this.compactMetadataStore(),
      this.rebuiltSearchIndexes(),
      this.cleanupObsoleteVersions(),
      this.optimizeMetadataQueries(),
    ];

    const results = await Promise.allSettled(optimizationTasks);

    const optimization: OptimizationResult = {
      startTime,
      endTime: Date.now(),
      duration: Date.now() - startTime,
      tasks: [
        { name: "compact_storage", success: results[0].status === "fulfilled" },
        { name: "rebuild_indexes", success: results[1].status === "fulfilled" },
        {
          name: "cleanup_versions",
          success: results[2].status === "fulfilled",
        },
        {
          name: "optimize_queries",
          success: results[3].status === "fulfilled",
        },
      ],
      spaceRecovered: await this.calculateSpaceRecovered(),
      performanceImprovement: await this.measurePerformanceImprovement(),
    };

    console.log("Metadata optimization completed:", optimization);
    return optimization;
  }

  // Initialize extractors for different file types
  private initializeExtractors(): void {
    this.extractors = new Map();

    // Image extractors
    this.extractors.set("image", new ImageMetadataExtractor());
    this.extractors.set("exif", new ExifExtractor());

    // Video extractors
    this.extractors.set("video", new VideoMetadataExtractor());
    this.extractors.set("ffprobe", new FFProbeExtractor());

    // Audio extractors
    this.extractors.set("audio", new AudioMetadataExtractor());
    this.extractors.set("id3", new ID3Extractor());

    // Document extractors
    this.extractors.set("pdf", new PDFMetadataExtractor());
    this.extractors.set("office", new OfficeMetadataExtractor());

    // General extractors
    this.extractors.set("mime", new MimeTypeExtractor());
    this.extractors.set("file", new FileSystemExtractor());

    console.log(`Initialized ${this.extractors.size} metadata extractors`);
  }

  private getExtractorsForMimeType(mimeType: string): MetadataExtractor[] {
    const extractors: MetadataExtractor[] = [];

    // Always include general extractors
    extractors.push(this.extractors.get("mime")!);
    extractors.push(this.extractors.get("file")!);

    // Add format-specific extractors
    if (mimeType.startsWith("image/")) {
      extractors.push(this.extractors.get("image")!);
      extractors.push(this.extractors.get("exif")!);
    } else if (mimeType.startsWith("video/")) {
      extractors.push(this.extractors.get("video")!);
      extractors.push(this.extractors.get("ffprobe")!);
    } else if (mimeType.startsWith("audio/")) {
      extractors.push(this.extractors.get("audio")!);
      extractors.push(this.extractors.get("id3")!);
    } else if (mimeType === "application/pdf") {
      extractors.push(this.extractors.get("pdf")!);
    } else if (this.isOfficeDocument(mimeType)) {
      extractors.push(this.extractors.get("office")!);
    }

    return extractors.filter((e) => e != null);
  }

  private calculateQualityScore(results: ExtractionResult[]): number {
    const totalExtractors = results.length;
    const successfulExtractors = results.filter((r) => r.success).length;

    if (totalExtractors === 0) return 0;

    return (successfulExtractors / totalExtractors) * 100;
  }

  // Utility methods
  private async storeMetadata(metadata: ExtractedMetadata): Promise<void> {
    await this.metadataStore.store(metadata);
    await this.versioning.createVersion(metadata);
  }

  private async indexMetadata(metadata: ExtractedMetadata): Promise<void> {
    await this.indexer.index(metadata);
  }

  private isOfficeDocument(mimeType: string): boolean {
    const officeMimes = [
      "application/msword",
      "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
      "application/vnd.ms-excel",
      "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
      "application/vnd.ms-powerpoint",
      "application/vnd.openxmlformats-officedocument.presentationml.presentation",
    ];

    return officeMimes.includes(mimeType);
  }

  private generateExtractionId(): string {
    return `ext_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`;
  }

  private generateBatchId(): string {
    return `batch_meta_${Date.now()}_${Math.random()
      .toString(36)
      .substr(2, 9)}`;
  }

  // Placeholder implementations
  private async getFileStats(filePath: string): Promise<any> {
    return { mtime: new Date(), size: 0 };
  }

  private async calculateChecksum(filePath: string): Promise<string> {
    return "checksum-placeholder";
  }

  private convertFiltersToSearchFilters(filters: MetadataFilters): any[] {
    return [];
  }

  private getAvailableFacets(): string[] {
    return ["mimeType", "size", "createdAt", "dimensions"];
  }

  private async calculateSearchFacets(
    results: any[],
    query: MetadataSearchQuery
  ): Promise<any> {
    return {};
  }

  private async generateSearchSuggestions(
    query: MetadataSearchQuery
  ): Promise<string[]> {
    return [];
  }

  private setupBackgroundProcessing(): void {
    // Setup background tasks for metadata processing
  }

  private async calculateFileTypeDistribution(
    criteria: AnalyticsCriteria
  ): Promise<any> {
    return {};
  }

  private async calculateSizeAnalytics(
    criteria: AnalyticsCriteria
  ): Promise<any> {
    return {};
  }

  private async calculateTemporalAnalytics(
    criteria: AnalyticsCriteria
  ): Promise<any> {
    return {};
  }

  private async calculateQualityMetrics(
    criteria: AnalyticsCriteria
  ): Promise<any> {
    return {};
  }

  private async calculateImageAnalytics(
    criteria: AnalyticsCriteria
  ): Promise<any> {
    return {};
  }

  private async calculateVideoAnalytics(
    criteria: AnalyticsCriteria
  ): Promise<any> {
    return {};
  }

  private async calculateAudioAnalytics(
    criteria: AnalyticsCriteria
  ): Promise<any> {
    return {};
  }

  private async calculateDocumentAnalytics(
    criteria: AnalyticsCriteria
  ): Promise<any> {
    return {};
  }

  private async compactMetadataStore(): Promise<void> {}
  private async rebuiltSearchIndexes(): Promise<void> {}
  private async cleanupObsoleteVersions(): Promise<void> {}
  private async optimizeMetadataQueries(): Promise<void> {}
  private async calculateSpaceRecovered(): Promise<number> {
    return 0;
  }
  private async measurePerformanceImprovement(): Promise<number> {
    return 0;
  }
}

// Example metadata extractor implementation
class ImageMetadataExtractor implements MetadataExtractor {
  getName(): string {
    return "image-metadata";
  }

  async extract(filePath: string, options: any): Promise<any> {
    // Would use libraries like sharp, image-size, etc.
    return {
      image: {
        width: 1920,
        height: 1080,
        colorSpace: "sRGB",
        channels: 3,
        density: 72,
        format: "jpeg",
        quality: 85,
        compression: "baseline",
      },
      technical: {
        bitDepth: 8,
        pixelDensity: 72,
        orientation: 1,
      },
      extractionTime: 50,
    };
  }
}

// Supporting interfaces and types
interface MetadataConfig {
  storage: any;
  indexing: any;
  search: any;
}

interface ExtractionOptions {
  fileId?: string;
  mimeType?: string;
  extractThumbnail?: boolean;
  deepAnalysis?: boolean;
}

interface ExtractionResult {
  extractorName: string;
  success: boolean;
  metadata?: any;
  error?: string;
  extractionTime: number;
}

interface CombinedMetadata {
  technical: any;
  descriptive: any;
  image?: any;
  video?: any;
  audio?: any;
  document?: any;
}

interface AdministrativeMetadata {
  fileId: string;
  createdAt: number;
  modifiedAt: number;
  size: number;
  checksum: string;
  storage: {
    location: string;
    provider: string;
    redundancy: string;
  };
  processing: {
    extractedAt: number;
    version: string;
  };
}

interface ExtractedMetadata {
  fileId: string;
  extractionId: string;
  extractedAt: number;
  extractionTime: number;
  technical: any;
  descriptive: any;
  administrative: AdministrativeMetadata;
  image?: any;
  video?: any;
  audio?: any;
  document?: any;
  extractionResults: ExtractionResult[];
  qualityScore: number;
}

interface MetadataSearchQuery {
  text?: string;
  fields?: string[];
  filters?: MetadataFilters;
  sort?: SortOption[];
  limit?: number;
  offset?: number;
  includeFacets?: boolean;
}

interface MetadataFilters {
  mimeTypes?: string[];
  dateRange?: { start: Date; end: Date };
  sizeRange?: { min: number; max: number };
  dimensions?: { minWidth: number; minHeight: number };
  durationRange?: { min: number; max: number };
  tags?: string[];
  userId?: string;
}

interface SortOption {
  field: string;
  direction: "asc" | "desc";
}

interface SearchParameters {
  text?: string;
  fields: string[];
  filters: any[];
  sort: SortOption[];
  limit: number;
  offset: number;
  facets: string[];
}

interface MetadataSearchResult {
  query: MetadataSearchQuery;
  results: MetadataSearchItem[];
  facets: any;
  totalResults: number;
  executionTime: number;
  suggestions: string[];
}

interface MetadataSearchItem {
  fileId: string;
  filename: string;
  mimeType: string;
  size: number;
  createdAt: number;
  thumbnail?: string;
  score: number;
  highlights: Record<string, string[]>;
}

interface BatchMetadataRequest {
  fileId: string;
  filePath: string;
  mimeType: string;
  options?: ExtractionOptions;
}

interface MetadataProcessingResult {
  fileId: string;
  success: boolean;
  metadata?: ExtractedMetadata;
  processingTime: number;
}

interface BatchMetadataError {
  index: number;
  fileId: string;
  error: string;
  code: string;
}

interface BatchMetadataResult {
  batchId: string;
  totalFiles: number;
  successfulProcessing: number;
  failedProcessing: number;
  results: MetadataProcessingResult[];
  errors: BatchMetadataError[];
  processingTime: number;
  completedAt: number;
}

interface AnalyticsCriteria {
  dateRange?: { start: Date; end: Date };
  fileTypes?: string[];
  users?: string[];
  tags?: string[];
}

interface MetadataAnalytics {
  criteria: AnalyticsCriteria;
  generatedAt: number;
  fileTypeDistribution: any;
  sizeAnalytics: any;
  temporalAnalytics: any;
  qualityMetrics: any;
  imageAnalytics?: any;
  videoAnalytics?: any;
  audioAnalytics?: any;
  documentAnalytics?: any;
}

interface OptimizationResult {
  startTime: number;
  endTime: number;
  duration: number;
  tasks: { name: string; success: boolean }[];
  spaceRecovered: number;
  performanceImprovement: number;
}

interface MetadataExtractor {
  getName(): string;
  extract(filePath: string, options: any): Promise<any>;
}

class MetadataError extends Error {
  constructor(
    message: string,
    public code: string,
    public status: number,
    public metadata?: any
  ) {
    super(message);
    this.name = "MetadataError";
  }
}

// Placeholder classes
class MetadataStore {
  constructor(config: any) {}
  async store(metadata: ExtractedMetadata): Promise<void> {}
}

class MetadataIndexer {
  constructor(config: any) {}
  async index(metadata: ExtractedMetadata): Promise<void> {}
}

class MetadataSearchEngine {
  constructor(config: any) {}
  async search(params: SearchParameters): Promise<any[]> {
    return [];
  }
}

class MetadataVersioning {
  async createVersion(metadata: ExtractedMetadata): Promise<void> {}
}

class MetadataAuditLogger {
  async logExtraction(
    extractionId: string,
    metadata: ExtractedMetadata
  ): Promise<void> {}
}

class MetadataScheduler {
  constructor() {}
}

class ExifExtractor implements MetadataExtractor {
  getName(): string {
    return "exif";
  }
  async extract(filePath: string, options: any): Promise<any> {
    return {};
  }
}

class VideoMetadataExtractor implements MetadataExtractor {
  getName(): string {
    return "video";
  }
  async extract(filePath: string, options: any): Promise<any> {
    return {};
  }
}

class FFProbeExtractor implements MetadataExtractor {
  getName(): string {
    return "ffprobe";
  }
  async extract(filePath: string, options: any): Promise<any> {
    return {};
  }
}

class AudioMetadataExtractor implements MetadataExtractor {
  getName(): string {
    return "audio";
  }
  async extract(filePath: string, options: any): Promise<any> {
    return {};
  }
}

class ID3Extractor implements MetadataExtractor {
  getName(): string {
    return "id3";
  }
  async extract(filePath: string, options: any): Promise<any> {
    return {};
  }
}

class PDFMetadataExtractor implements MetadataExtractor {
  getName(): string {
    return "pdf";
  }
  async extract(filePath: string, options: any): Promise<any> {
    return {};
  }
}

class OfficeMetadataExtractor implements MetadataExtractor {
  getName(): string {
    return "office";
  }
  async extract(filePath: string, options: any): Promise<any> {
    return {};
  }
}

class MimeTypeExtractor implements MetadataExtractor {
  getName(): string {
    return "mime";
  }
  async extract(filePath: string, options: any): Promise<any> {
    return {};
  }
}

class FileSystemExtractor implements MetadataExtractor {
  getName(): string {
    return "file";
  }
  async extract(filePath: string, options: any): Promise<any> {
    return {};
  }
}