import { Injectable } from '@nestjs/common';
import * as fs from 'fs';
import * as path from 'path';

@Injectable()
export class FileStorageService {
  read<T>(filepath: string): T | null {
    try {
      if (!fs.existsSync(filepath)) return null;
      const content = fs.readFileSync(filepath, 'utf-8');
      return JSON.parse(content) as T;
    } catch {
      return null;
    }
  }

  write<T>(filepath: string, data: T): void {
    const dir = path.dirname(filepath);
    if (!fs.existsSync(dir)) {
      fs.mkdirSync(dir, { recursive: true });
    }
    fs.writeFileSync(filepath, JSON.stringify(data, null, 2), 'utf-8');
  }
}