interface HTMLReportOptions {
  title?: string
  includeCharts?: boolean
  includeSummary?: boolean
  resultsPerPage?: number
}

function generateHTMLReport(
  results: MeasurementResult[],
  options?: HTMLReportOptions
): string {
  // Returns complete HTML as string
  // Simple table format, no JavaScript
  // Single-file, self-contained
  // <2 second render time
}

interface CSVExportOptions {
  includeDetails?: boolean
  separator?: ',' | ';' | '\t'
  encoding?: 'utf-8' | 'utf-8-bom'
}

function exportToCSV(
  results: MeasurementResult[],
  options?: CSVExportOptions
): string {
  // Proper CSV format
  // UTF-8 encoding with BOM (Excel compatibility)
  // Escape quotes, newlines
  // Test with Excel, Google Sheets, LibreOffice
}

interface MarkdownExportOptions {
  includeDetails?: boolean
  groupByLanguage?: boolean
  includeCharts?: boolean
}

function exportToMarkdown(
  results: MeasurementResult[],
  options?: MarkdownExportOptions
): string {
  // GitHub Flavored Markdown
  // Summary section
  // Results by language
  // Severity breakdown
  // Copy-pasteable to issues
}

function exportToJSON(results: MeasurementResult[]): string {
  return JSON.stringify(results, null, 2)
}

class ReportFormatter {
  constructor(results: MeasurementResult[])
  
  toHTML(options?: HTMLReportOptions): string
  toCSV(options?: CSVExportOptions): string
  toMarkdown(options?: MarkdownExportOptions): string
  toJSON(): string
  toConsole(): string
  
  filterByLanguage(language: string): ReportFormatter
  filterBySeverity(severity: MeasurementSeverity): ReportFormatter
  sortByDelta(ascending?: boolean): ReportFormatter
  
  summary(): ReportSummary
  statisticsByLanguage(): Record<string, LanguageStats>
}

// Command structure:
// npm run validator [command] [options]

// Commands:
// - validate [options]    Validate measurements
// - report [options]      Generate reports
// - help                  Show help

// Example usage:
// npm run validator validate --corpus=all --report=csv
// npm run validator report --input=results.json --format=html
// npm run validator validate --language=ar --severity=warning