import fs from 'node:fs/promises';
import path from 'node:path';
import type { PackageFacts, RepoKind } from '../types.js';
export async function classifyRepository(
  repoPath: string,
  facts: PackageFacts
): Promise<RepoKind> {
  const hasCdsDep = Boolean(
    facts.dependencies['@sap/cds'] ??
    facts.dependencies.cds ??
    facts.dependencies['cds-routing-handlers']
  );
  const cdsFiles = await findFiles(repoPath, '.cds');
  const serverFiles = await Promise.all(
    ['srv/server.ts', 'srv/server.js', 'src/server.ts', 'src/server.js'].map(
      async (f) =>
        fs
          .access(path.join(repoPath, f))
          .then(() => true)
          .catch(() => false)
    )
  );
  const helper =
    Object.keys(facts.dependencies).includes('cds-routing-handlers') ||
    facts.packageName?.includes('helper') === true;
  if (helper && cdsFiles.length > 0) return 'mixed';
  if (helper) return 'helper-package';
  if (hasCdsDep && (cdsFiles.length > 0 || serverFiles.some(Boolean)))
    return 'cap-service';
  if (cdsFiles.length > 0)
    return serverFiles.some(Boolean) ? 'cap-service' : 'cap-db-model';
  return 'unknown';
}

async function findFiles(root: string, suffix: string): Promise<string[]> {
  const out: string[] = [];
  async function walk(dir: string): Promise<void> {
    const entries = await fs
      .readdir(dir, { withFileTypes: true })
      .catch(() => []);
    for (const e of entries) {
      if (e.isDirectory()) {
        if (!['node_modules', 'dist', 'gen', '.git'].includes(e.name))
          await walk(path.join(dir, e.name));
      } else if (e.name.endsWith(suffix)) out.push(path.join(dir, e.name));
    }
  }
  await walk(root);
  return out;
}