/**
 * Export utilities for downloading data in various formats
 */

/**
 * Export data as JSON file
 */
export function exportJSON(data: any, filename: string) {
  const json = JSON.stringify(data, null, 2);
  const blob = new Blob([json], { type: "application/json" });
  downloadBlob(blob, `${filename}.json`);
}

/**
 * Export data as CSV file
 */
export function exportCSV(data: any[], filename: string, headers?: string[]) {
  if (data.length === 0) {
    throw new Error("No data to export");
  }

  // Get headers from first object if not provided
  const csvHeaders = headers || Object.keys(data[0]);
  
  // Create CSV content
  const csvRows = [
    csvHeaders.join(","), // Header row
    ...data.map(row => 
      csvHeaders.map(header => {
        const value = row[header];
        // Escape quotes and wrap in quotes if contains comma or quote
        const stringValue = String(value ?? "");
        if (stringValue.includes(",") || stringValue.includes('"') || stringValue.includes("\n")) {
          return `"${stringValue.replace(/"/g, '""')}"`;
        }
        return stringValue;
      }).join(",")
    )
  ];

  const csv = csvRows.join("\n");
  const blob = new Blob([csv], { type: "text/csv" });
  downloadBlob(blob, `${filename}.csv`);
}

/**
 * Export data as text file
 */
export function exportText(text: string, filename: string) {
  const blob = new Blob([text], { type: "text/plain" });
  downloadBlob(blob, `${filename}.txt`);
}

/**
 * Download a blob as a file
 */
function downloadBlob(blob: Blob, filename: string) {
  const url = URL.createObjectURL(blob);
  const link = document.createElement("a");
  link.href = url;
  link.download = filename;
  document.body.appendChild(link);
  link.click();
  document.body.removeChild(link);
  URL.revokeObjectURL(url);
}

/**
 * Copy text to clipboard
 */
export async function copyToClipboard(text: string): Promise<boolean> {
  try {
    await navigator.clipboard.writeText(text);
    return true;
  } catch (err) {
    // Fallback for older browsers
    const textarea = document.createElement("textarea");
    textarea.value = text;
    textarea.style.position = "fixed";
    textarea.style.opacity = "0";
    document.body.appendChild(textarea);
    textarea.select();
    const success = document.execCommand("copy");
    document.body.removeChild(textarea);
    return success;
  }
}

/**
 * Format data for export with timestamps
 */
export function prepareExportData(data: any[], includeTimestamp = true) {
  if (!includeTimestamp) return data;

  return data.map(item => ({
    ...item,
    exported_at: new Date().toISOString(),
  }));
}

/**
 * Generate filename with timestamp
 */
export function generateFilename(base: string, extension?: string): string {
  const timestamp = new Date().toISOString().replace(/[:.]/g, "-").slice(0, -5);
  const ext = extension ? `.${extension}` : "";
  return `${base}_${timestamp}${ext}`;
}