/**
 * Excel Processor
 *
 * Handles downloading, validating, and processing Excel files (.xlsx, .xls).
 * Uses exceljs library for parsing with streaming support for large files.
 *
 * Key features:
 * - Supports both .xlsx and legacy .xls formats
 * - Extracts worksheet data with headers
 * - Handles complex cell types (formulas, rich text, dates)
 * - Respects configurable row and sheet limits
 * - Provides truncation metadata when limits are exceeded
 *
 * @module processors/document/ExcelProcessor
 *
 * @example
 * ```typescript
 * import { excelProcessor, processExcel, isExcelFile } from "./ExcelProcessor.js";
 *
 * // Check if a file is an Excel file
 * if (isExcelFile(fileInfo.mimetype, fileInfo.name)) {
 *   // Process the Excel file
 *   const result = await processExcel(fileInfo, {
 *     authHeaders: { Authorization: "Bearer token" },
 *   });
 *
 *   if (result.success) {
 *     console.log(`Processed ${result.data.sheetCount} sheets`);
 *     console.log(`Total rows: ${result.data.totalRows}`);
 *
 *     for (const sheet of result.data.worksheets) {
 *       console.log(`Sheet: ${sheet.name}, Rows: ${sheet.rowCount}`);
 *     }
 *   }
 * }
 * ```
 */
import { BaseFileProcessor } from "../base/BaseFileProcessor.js";
import type { FileInfo, ProcessOptions, ProcessedExcel, ProcessorFileProcessingResult } from "../../types/index.js";
/**
 * Excel Processor - handles .xlsx and .xls files.
 * Uses exceljs library for parsing with support for large files.
 *
 * Features:
 * - ZIP format validation (XLSX files are ZIP archives)
 * - Sheet count limiting (MAX_EXCEL_SHEETS)
 * - Row count limiting per sheet (MAX_EXCEL_ROWS)
 * - Cell type handling (text, numbers, formulas, dates, rich text)
 *
 * @example
 * ```typescript
 * const processor = new ExcelProcessor();
 *
 * // Process a file
 * const result = await processor.processFile(fileInfo, {
 *   authHeaders: { Authorization: "Bearer token" },
 * });
 *
 * if (result.success) {
 *   console.log(`Sheets: ${result.data.sheetCount}`);
 *   console.log(`Truncated: ${result.data.truncated}`);
 * }
 * ```
 */
export declare class ExcelProcessor extends BaseFileProcessor<ProcessedExcel> {
    constructor();
    /**
     * Validate downloaded Excel file has correct format.
     * XLSX files are ZIP archives starting with PK signature.
     *
     * @param buffer - Downloaded file content
     * @param _fileInfo - Original file information (unused but required by interface)
     * @returns null if valid, error message if invalid
     */
    protected validateDownloadedFile(buffer: Buffer, _fileInfo: FileInfo): Promise<string | null>;
    /**
     * Build processed result stub.
     * Note: This is a synchronous stub - actual parsing happens in processFile override.
     *
     * @param buffer - Downloaded file content
     * @param fileInfo - Original file information
     * @returns Empty ProcessedExcel structure (populated by processFile)
     */
    protected buildProcessedResult(buffer: Buffer, fileInfo: FileInfo): ProcessedExcel;
    /**
     * Override processFile for async Excel parsing with exceljs.
     * This override is necessary because exceljs uses async parsing.
     *
     * @param fileInfo - File information (can include URL or buffer)
     * @param options - Optional processing options (auth headers, timeout, etc.)
     * @returns Processing result with parsed Excel data or error
     */
    processFile(fileInfo: FileInfo, options?: ProcessOptions): Promise<ProcessorFileProcessingResult<ProcessedExcel>>;
    /**
     * Parse Excel buffer into workbook using exceljs.
     *
     * @param buffer - Excel file content
     * @returns Parsed ExcelJS Workbook
     */
    private parseWorkbook;
    /**
     * Extract worksheet data from workbook with row and sheet limits.
     *
     * @param workbook - Parsed ExcelJS Workbook
     * @returns Extracted worksheets with truncation metadata
     */
    private extractWorksheets;
    /**
     * Convert an Excel cell value to a primitive type.
     * Handles various cell types including formulas, rich text, and dates.
     *
     * @param cell - ExcelJS cell value (can be various types)
     * @returns Primitive value (string, number, boolean, or null)
     */
    private getCellValue;
    /**
     * Extract text from rich text cell format.
     * Rich text cells contain an array of text fragments with formatting.
     *
     * @param richText - Array of rich text fragments
     * @returns Concatenated plain text
     */
    private extractRichText;
    /**
     * Extract a specific range from a spreadsheet.
     *
     * Called by the `extract_file_content` tool for targeted data access.
     * Returns TSV-formatted text for the specified sheet, row range, and columns.
     *
     * @param buffer - Excel file buffer
     * @param sheet - Sheet name or 0-based index (default: first sheet)
     * @param rowStart - Starting row (1-indexed, default: 1)
     * @param rowEnd - Ending row (1-indexed, default: all rows)
     * @param columns - Specific column letters to include (e.g., ["A", "B", "D"])
     * @returns TSV-formatted string with the extracted data
     */
    extractSheetRange(buffer: Buffer, sheet?: string | number, rowStart?: number, rowEnd?: number, columns?: string[]): Promise<string>;
}
/**
 * Singleton Excel processor instance.
 * Use this for standard Excel processing operations.
 *
 * @example
 * ```typescript
 * import { excelProcessor } from "./ExcelProcessor.js";
 *
 * const result = await excelProcessor.processFile(fileInfo);
 * ```
 */
export declare const excelProcessor: ExcelProcessor;
/**
 * Check if a file is an Excel file.
 * Matches by MIME type or file extension.
 *
 * @param mimetype - MIME type of the file
 * @param filename - Filename (for extension-based detection)
 * @returns true if the file is an Excel file
 *
 * @example
 * ```typescript
 * if (isExcelFile("application/vnd.ms-excel", "data.xls")) {
 *   // Process as Excel
 * }
 *
 * if (isExcelFile("", "report.xlsx")) {
 *   // Also matches by extension
 * }
 * ```
 */
export declare function isExcelFile(mimetype: string, filename: string): boolean;
/**
 * Validate Excel file size against configured limit.
 *
 * @param sizeBytes - File size in bytes
 * @returns true if size is within the Excel file limit
 *
 * @example
 * ```typescript
 * if (!validateExcelSize(fileInfo.size)) {
 *   console.error(`File too large: max ${SIZE_LIMITS.EXCEL_MAX_MB}MB`);
 * }
 * ```
 */
export declare function validateExcelSize(sizeBytes: number): boolean;
/**
 * Process a single Excel file.
 * Convenience function that uses the singleton processor.
 *
 * @param fileInfo - File information (can include URL or buffer)
 * @param options - Optional processing options (auth headers, timeout, etc.)
 * @returns Processing result with parsed Excel data or error
 *
 * @example
 * ```typescript
 * import { processExcel } from "./ExcelProcessor.js";
 *
 * const result = await processExcel(fileInfo, {
 *   authHeaders: { Authorization: "Bearer token" },
 *   timeout: 120000, // 2 minutes for large files
 * });
 *
 * if (result.success) {
 *   const { worksheets, totalRows, truncated } = result.data;
 *   console.log(`Extracted ${totalRows} rows from ${worksheets.length} sheets`);
 *
 *   if (truncated) {
 *     console.warn("Some data was truncated due to size limits");
 *   }
 * } else {
 *   console.error(`Processing failed: ${result.error?.userMessage}`);
 * }
 * ```
 */
export declare function processExcel(fileInfo: FileInfo, options?: ProcessOptions): Promise<ProcessorFileProcessingResult<ProcessedExcel>>;
/**
 * Get Excel max size in MB.
 *
 * @returns Maximum Excel file size in megabytes
 *
 * @example
 * ```typescript
 * const maxSize = getExcelMaxSizeMB(); // 10
 * console.log(`Maximum Excel file size: ${maxSize}MB`);
 * ```
 */
export declare function getExcelMaxSizeMB(): number;
/**
 * Get Excel max rows per sheet.
 *
 * @returns Maximum rows to process per worksheet
 *
 * @example
 * ```typescript
 * const maxRows = getExcelMaxRows(); // 5000
 * console.log(`Maximum rows per sheet: ${maxRows}`);
 * ```
 */
export declare function getExcelMaxRows(): number;
/**
 * Get Excel max sheets to process.
 *
 * @returns Maximum number of worksheets to process
 *
 * @example
 * ```typescript
 * const maxSheets = getExcelMaxSheets(); // 10
 * console.log(`Maximum sheets to process: ${maxSheets}`);
 * ```
 */
export declare function getExcelMaxSheets(): number;