import OpenAI from "openai";
import type {
  Message,
  ModelEvent,
  ModelPort,
  ModelRequest,
} from "@great-agent/agent-core";

export type DeepSeekModelOptions = Readonly<{
  apiKey: string;
  baseURL: string;
  model: string;
}>;

export class DeepSeekModelAdapter implements ModelPort {
  private readonly client: OpenAI;

  constructor(private readonly options: DeepSeekModelOptions) {
    this.client = new OpenAI({
      apiKey: options.apiKey,
      baseURL: options.baseURL,
    });
  }

  async *stream(
    request: ModelRequest,
    signal: AbortSignal,
  ): AsyncIterable<ModelEvent> {
    const response = await this.client.chat.completions.create(
      {
        model: request.model === "default" ? this.options.model : request.model,
        messages: request.messages.map(toModelMessage),
        stream: true,
      },
      { signal },
    );
    for await (const chunk of response) {
      const delta = chunk.choices[0]?.delta.content;
      if (delta) yield { type: "text.delta", delta };
    }
    yield { type: "response.completed" };
  }
}

function toModelMessage(
  message: Message,
): OpenAI.Chat.Completions.ChatCompletionMessageParam {
  return { role: message.role, content: message.content };
}