#!/usr/bin/env tsx
/**
 * Downloads official XRechnung Schematron validation rules
 * from the KoSIT repositories
 */

import * as fs from 'fs';
import * as path from 'path';
import { execSync } from 'child_process';

const XRECHNUNG_VERSION = '3.0.2'; // Latest version as of 2025
const VALIDATOR_VERSION = '2025-07-31'; // Next release date

const REPOS = {
  schematron: {
    url: 'https://github.com/itplr-kosit/xrechnung-schematron/archive/refs/tags/release-3.0.2.zip',
    dir: 'xrechnung-schematron'
  },
  validator: {
    url: 'https://github.com/itplr-kosit/validator-configuration-xrechnung/releases/download/release-2024-07-31/validator-configuration-xrechnung_3.0.1_2024-07-31.zip',
    dir: 'xrechnung-validator'
  }
};

const ASSETS_DIR = path.join(process.cwd(), 'assets', 'schematron', 'xrechnung');

async function downloadFile(url: string, destination: string): Promise<void> {
  console.log(`Downloading ${url}...`);
  
  try {
    // Use curl to download the file
    execSync(`curl -L -o "${destination}" "${url}"`, { stdio: 'inherit' });
    console.log(`Downloaded to ${destination}`);
  } catch (error) {
    console.error(`Failed to download ${url}:`, error);
    throw error;
  }
}

async function extractZip(zipFile: string, destination: string): Promise<void> {
  console.log(`Extracting ${zipFile}...`);
  
  try {
    // Create destination directory if it doesn't exist
    fs.mkdirSync(destination, { recursive: true });
    
    // Extract using unzip
    execSync(`unzip -o "${zipFile}" -d "${destination}"`, { stdio: 'inherit' });
    console.log(`Extracted to ${destination}`);
  } catch (error) {
    console.error(`Failed to extract ${zipFile}:`, error);
    throw error;
  }
}

async function downloadXRechnungRules(): Promise<void> {
  console.log('Starting XRechnung Schematron rules download...\n');
  
  // Create assets directory
  fs.mkdirSync(ASSETS_DIR, { recursive: true });
  
  const tempDir = path.join(ASSETS_DIR, 'temp');
  fs.mkdirSync(tempDir, { recursive: true });
  
  // Download and extract Schematron rules
  console.log('1. Downloading XRechnung Schematron rules...');
  const schematronZip = path.join(tempDir, 'xrechnung-schematron.zip');
  await downloadFile(REPOS.schematron.url, schematronZip);
  
  const schematronDir = path.join(ASSETS_DIR, REPOS.schematron.dir);
  await extractZip(schematronZip, schematronDir);
  
  // Find the actual Schematron files
  const schematronExtractedDir = path.join(schematronDir, `xrechnung-schematron-release-${XRECHNUNG_VERSION}`);
  const schematronValidationDir = path.join(schematronExtractedDir, 'validation', 'schematron');
  
  if (fs.existsSync(schematronValidationDir)) {
    console.log('\nFound Schematron validation files:');
    
    // List UBL Schematron files
    const ublDir = path.join(schematronValidationDir, 'ubl-inv');
    if (fs.existsSync(ublDir)) {
      const ublFiles = fs.readdirSync(ublDir).filter(f => f.endsWith('.sch') || f.endsWith('.xsl'));
      console.log('  UBL Invoice Schematron:', ublFiles.join(', '));
    }
    
    // List CII Schematron files
    const ciiDir = path.join(schematronValidationDir, 'cii');
    if (fs.existsSync(ciiDir)) {
      const ciiFiles = fs.readdirSync(ciiDir).filter(f => f.endsWith('.sch') || f.endsWith('.xsl'));
      console.log('  CII Schematron:', ciiFiles.join(', '));
    }
    
    // Copy to final location
    const finalUblDir = path.join(ASSETS_DIR, 'ubl');
    const finalCiiDir = path.join(ASSETS_DIR, 'cii');
    
    fs.mkdirSync(finalUblDir, { recursive: true });
    fs.mkdirSync(finalCiiDir, { recursive: true });
    
    // Copy UBL files
    if (fs.existsSync(ublDir)) {
      const ublFiles = fs.readdirSync(ublDir);
      for (const file of ublFiles) {
        if (file.endsWith('.sch') || file.endsWith('.xsl')) {
          fs.copyFileSync(
            path.join(ublDir, file),
            path.join(finalUblDir, file)
          );
        }
      }
      console.log(`\nCopied UBL Schematron files to ${finalUblDir}`);
    }
    
    // Copy CII files
    if (fs.existsSync(ciiDir)) {
      const ciiFiles = fs.readdirSync(ciiDir);
      for (const file of ciiFiles) {
        if (file.endsWith('.sch') || file.endsWith('.xsl')) {
          fs.copyFileSync(
            path.join(ciiDir, file),
            path.join(finalCiiDir, file)
          );
        }
      }
      console.log(`Copied CII Schematron files to ${finalCiiDir}`);
    }
  }
  
  // Download validator configuration (contains additional rules and scenarios)
  console.log('\n2. Downloading XRechnung validator configuration...');
  const validatorZip = path.join(tempDir, 'xrechnung-validator.zip');
  await downloadFile(REPOS.validator.url, validatorZip);
  
  const validatorDir = path.join(ASSETS_DIR, REPOS.validator.dir);
  await extractZip(validatorZip, validatorDir);
  
  // Create metadata file
  const metadata = {
    version: XRECHNUNG_VERSION,
    validatorVersion: VALIDATOR_VERSION,
    downloadDate: new Date().toISOString(),
    sources: {
      schematron: REPOS.schematron.url,
      validator: REPOS.validator.url
    },
    files: {
      ubl: fs.existsSync(path.join(ASSETS_DIR, 'ubl')) 
        ? fs.readdirSync(path.join(ASSETS_DIR, 'ubl')).filter(f => f.endsWith('.sch'))
        : [],
      cii: fs.existsSync(path.join(ASSETS_DIR, 'cii'))
        ? fs.readdirSync(path.join(ASSETS_DIR, 'cii')).filter(f => f.endsWith('.sch'))
        : []
    }
  };
  
  fs.writeFileSync(
    path.join(ASSETS_DIR, 'metadata.json'),
    JSON.stringify(metadata, null, 2)
  );
  
  // Clean up temp directory
  console.log('\n3. Cleaning up...');
  fs.rmSync(tempDir, { recursive: true, force: true });
  
  console.log('\n✅ XRechnung Schematron rules downloaded successfully!');
  console.log(`📁 Files are located in: ${ASSETS_DIR}`);
  console.log('\nNext steps:');
  console.log('1. Run Saxon-JS to compile .sch files to SEF format');
  console.log('2. Integrate with SchematronValidator');
  console.log('3. Add XRechnung-specific TypeScript validators');
}

// Run if executed directly
if (import.meta.url === `file://${process.argv[1]}`) {
  downloadXRechnungRules().catch(error => {
    console.error('Failed to download XRechnung rules:', error);
    process.exit(1);
  });
}

export default downloadXRechnungRules;