import fs from "fs";
import path from "path";

// Define a simple shape for what a discovered dataset looks like
export interface Wordlist {
  language: string;
  pos: string;
  sourcePath: string;
  outputDir: string;
}

/**
 * Scans the source-data directory to find all available word lists.
 */
export function scanSourceData(baseDir: string): Wordlist[] {
  const sourceBaseDir = path.join(baseDir, "source-data");
  const discoveredWordlists: Wordlist[] = [];

  // Safety check: if there's no source-data folder, return an empty array
  if (!fs.existsSync(sourceBaseDir)) {
    return discoveredWordlists;
  }

  // 1. Read the language directories (e.g., ['english'])
  const languages = fs.readdirSync(sourceBaseDir);

  for (const lang of languages) {
    const langFolderPath = path.join(sourceBaseDir, lang);

    // Make sure it's a directory, not a stray file
    if (!fs.statSync(langFolderPath).isDirectory()) continue;

    // 2. Read the files inside the language folder (e.g., ['nouns'])
    const posFiles = fs.readdirSync(langFolderPath);

    for (const pos of posFiles) {
      const fullSourcePath = path.join(langFolderPath, pos);

      // Make sure it's a file (like your extensionless "nouns" file)
      if (!fs.statSync(fullSourcePath).isFile()) continue;

      // 3. Package everything into a flat item and add it to our array
      discoveredWordlists.push({
        language: lang,
        pos: pos,
        sourcePath: fullSourcePath,
        outputDir: path.join(baseDir, "worddata", lang, pos),
      });
    }
  }

  // show summary
  console.log(
    `✅ Scan complete! Found ${discoveredWordlists.length} wordlist(s):`,
  );
  for (const list of discoveredWordlists) {
    console.log(`   • ${list.language.toUpperCase()} (${list.pos})`);
  }

  return discoveredWordlists;
}