import { Injectable, Logger } from '@nestjs/common';
import * as fs from 'fs';
import * as path from 'path';
import { randomUUID } from 'crypto';

const UPLOAD_DIR = path.resolve(process.cwd(), 'uploads', 'media');

const MIME_TO_EXT: Record<string, string> = {
  'image/jpeg':       '.jpg',
  'image/png':        '.png',
  'image/webp':       '.webp',
  'audio/ogg':        '.ogg',
  'audio/mpeg':       '.mp3',
  'audio/mp4':        '.m4a',
  'audio/amr':        '.amr',
  'video/mp4':        '.mp4',
  'video/3gpp':       '.3gp',
  'application/pdf':  '.pdf',
  'application/vnd.openxmlformats-officedocument.wordprocessingml.document':   '.docx',
  'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':         '.xlsx',
  'application/vnd.openxmlformats-officedocument.presentationml.presentation': '.pptx',
};

@Injectable()
export class LocalDiskAdapter {
  private readonly logger = new Logger(LocalDiskAdapter.name);

  constructor() {
    fs.mkdirSync(UPLOAD_DIR, { recursive: true });
  }

  async upload(buffer: Buffer, mimeType: string): Promise<string> {
    const ext = MIME_TO_EXT[mimeType] ?? '.bin';
    const filename = `${randomUUID()}${ext}`;
    const filepath = path.join(UPLOAD_DIR, filename);
    fs.writeFileSync(filepath, buffer);
    this.logger.log(`Mídia salva: ${filepath}`);
    return `/uploads/media/${filename}`;
  }

  delete(relativePath: string): void {
    try {
      fs.unlinkSync(path.join(process.cwd(), relativePath));
    } catch {
      this.logger.warn(`Falha ao deletar mídia: ${relativePath}`);
    }
  }
}