import { getLlamacppUrl, getLlamacppApiKey, getLlamacppPreamble } from '../config.js';

interface LlamaRequest {
  messages: Array<{ role: string; content: string }>;
}

interface LlamaChatChoice {
  message: {
    content: string;
  };
}

interface LlamaResponse {
  choices?: LlamaChatChoice[];
}

export const llamacppService = {
  async chat(messages: Array<{ role: string; content: string }>): Promise<string> {
    const apiUrl = getLlamacppUrl();
    if (!apiUrl) {
      return '';
    }

    const apiKey = getLlamacppApiKey();
    const headers: Record<string, string> = { 'Content-Type': 'application/json' };
    if (apiKey) {
      headers['Authorization'] = `Bearer ${apiKey}`;
    }

    const response = await fetch(apiUrl, {
      method: 'POST',
      headers,
      body: JSON.stringify({ messages } satisfies LlamaRequest),
    });

    if (!response.ok) {
      const text = await response.text().catch(() => '');
      throw new Error(`llama.cpp request failed (${response.status}): ${text.slice(0, 300)}`);
    }

    const data = (await response.json()) as LlamaResponse;
    const content = data.choices?.[0]?.message?.content?.trim() ?? '';
    return content;
  },

  async chatWithPreamble(userText: string): Promise<string> {
    const preamble = getLlamacppPreamble();
    const messages = preamble ? [
      { role: 'system', content: preamble },
      { role: 'user', content: userText },
    ] : [{ role: 'user', content: userText }];
    return this.chat(messages);
  },
};