import { NexusError } from '../shared/errors.js';
import type { Capability, MediaProvider, SearchProvider, SttProvider } from './types.js';

/**
 * Registry maps a provider name + capability to the concrete adapter.
 * Adding RouterAI / GPTunnel / OpenRouter / cloud STT means registering a new
 * adapter here — no changes needed in the MCP tool layer.
 */
export class ProviderRegistry {
  private media = new Map<string, MediaProvider>();
  private search = new Map<string, SearchProvider>();
  private stt = new Map<string, SttProvider>();

  registerMedia(provider: MediaProvider): void {
    this.media.set(provider.name, provider);
  }
  registerSearch(provider: SearchProvider): void {
    this.search.set(provider.name, provider);
  }
  registerStt(provider: SttProvider): void {
    this.stt.set(provider.name, provider);
  }

  getMedia(name: string, capability: Capability): MediaProvider {
    const p = this.media.get(name);
    if (!p) {
      throw new NexusError(
        'UNSUPPORTED',
        `Unknown media provider "${name}". Available: ${[...this.media.keys()].join(', ') || 'none'}`
      );
    }
    if (!p.capabilities.includes(capability)) {
      throw new NexusError(
        'UNSUPPORTED',
        `Provider "${name}" does not support capability "${capability}"`
      );
    }
    return p;
  }

  getSearch(name: string): SearchProvider {
    const p = this.search.get(name);
    if (!p) {
      throw new NexusError(
        'UNSUPPORTED',
        `Unknown search provider "${name}". Available: ${[...this.search.keys()].join(', ') || 'none'}`
      );
    }
    return p;
  }

  getStt(name: string): SttProvider {
    const p = this.stt.get(name);
    if (!p) {
      throw new NexusError(
        'UNSUPPORTED',
        `Unknown STT provider "${name}". Available: ${[...this.stt.keys()].join(', ') || 'none'}`
      );
    }
    return p;
  }

  listMediaProviders(): string[] {
    return [...this.media.keys()];
  }
  listSearchProviders(): string[] {
    return [...this.search.keys()];
  }
  listSttProviders(): string[] {
    return [...this.stt.keys()];
  }
}