import SftpClient from "ssh2-sftp-client";
import { localStorageGet } from "./localStorage";
import { getUserSettings } from "./db";

export interface SftpConfig {
  host: string;
  port: number;
  username: string;
  password: string;
  remotePath: string;
}

/**
 * Test SFTP connection
 */
export async function testSftpConnection(config: SftpConfig): Promise<boolean> {
  const sftp = new SftpClient();
  
  try {
    await sftp.connect({
      host: config.host,
      port: config.port,
      username: config.username,
      password: config.password,
    });
    
    console.log("[SFTP] Connection successful");
    return true;
  } catch (error) {
    console.error("[SFTP] Connection failed:", error);
    return false;
  } finally {
    await sftp.end();
  }
}

/**
 * Export invoice files (PDF + JSON) to SFTP server
 */
export async function exportInvoiceToSftp(
  config: SftpConfig,
  pdfFileKey: string,
  jsonFileKey: string | null,
  invoiceDate: Date
): Promise<void> {
  const sftp = new SftpClient();
  
  try {
    // Connect to SFTP
    await sftp.connect({
      host: config.host,
      port: config.port,
      username: config.username,
      password: config.password,
    });
    
    console.log("[SFTP] Connected successfully");
    
    // Create directory structure: remotePath/YYYY/MM/DD
    const year = invoiceDate.getFullYear();
    const month = String(invoiceDate.getMonth() + 1).padStart(2, "0");
    const day = String(invoiceDate.getDate()).padStart(2, "0");
    
    const targetDir = `${config.remotePath}/${year}/${month}/${day}`.replace(/\/+/g, "/");
    
    // Ensure directory exists
    await sftp.mkdir(targetDir, true);
    
    console.log(`[SFTP] Created directory: ${targetDir}`);
    
    // Upload PDF file
    const pdfBuffer = await localStorageGet(pdfFileKey);
    const pdfFileName = pdfFileKey.split("/").pop() || "invoice.pdf";
    const pdfRemotePath = `${targetDir}/${pdfFileName}`;
    
    await sftp.put(pdfBuffer, pdfRemotePath);
    console.log(`[SFTP] Uploaded PDF: ${pdfRemotePath}`);
    
    // Upload JSON metadata file if exists
    if (jsonFileKey) {
      const jsonBuffer = await localStorageGet(jsonFileKey);
      const jsonFileName = jsonFileKey.split("/").pop() || "metadata.json";
      const jsonRemotePath = `${targetDir}/${jsonFileName}`;
      
      await sftp.put(jsonBuffer, jsonRemotePath);
      console.log(`[SFTP] Uploaded JSON: ${jsonRemotePath}`);
    }
    
    console.log("[SFTP] Export completed successfully");
  } catch (error) {
    console.error("[SFTP] Export failed:", error);
    throw error;
  } finally {
    await sftp.end();
  }
}

/**
 * Get SFTP configuration for a user
 */
export async function getUserSftpConfig(userId: number): Promise<SftpConfig | null> {
  const settings = await getUserSettings(userId);
  
  if (!settings || !settings.sftpHost || !settings.sftpUsername || !settings.sftpPassword) {
    return null;
  }
  
  return {
    host: settings.sftpHost,
    port: settings.sftpPort || 22,
    username: settings.sftpUsername,
    password: settings.sftpPassword,
    remotePath: settings.sftpRemotePath || "/",
  };
}