/** Auto-detect available LLM providers from environment variables */

import type { DetectedProvider } from './types.js';

const PROVIDER_ENV_MAP: Record<string, {
  keys: string[];
  label: string;
  model: string;
}> = {
  openai:      { keys: ['OPENAI_API_KEY'],                    label: 'OpenAI GPT-5.4',       model: 'gpt-5.4' },
  anthropic:   { keys: ['ANTHROPIC_API_KEY'],                 label: 'Claude Sonnet 4.6',     model: 'claude-sonnet-4-6' },
  xai:         { keys: ['XAI_API_KEY', 'GROK_API_KEY'],      label: 'xAI Grok 4',           model: 'grok-4' },
  mistral:     { keys: ['MISTRAL_API_KEY'],                   label: 'Mistral Large',         model: 'mistral-large-latest' },
  cohere:      { keys: ['COHERE_API_KEY'],                    label: 'Cohere Command R+',     model: 'command-r-plus-08-2024' },
  gemini:      { keys: ['GEMINI_API_KEY'],                    label: 'Google Gemini 2.5',     model: 'gemini-2.5-flash' },
  perplexity:  { keys: ['PERPLEXITY_API_KEY'],                label: 'Perplexity Sonar Pro',  model: 'sonar-pro' },
  groq:        { keys: ['GROQ_API_KEY'],                      label: 'Groq',                  model: 'llama-3.3-70b-versatile' },
  huggingface: { keys: ['HF_API_KEY', 'HUGGINGFACE_API_KEY'], label: 'HuggingFace Qwen 3.5',  model: 'Qwen/Qwen3.5-9B' },
};

/**
 * Scan process.env for provider API keys and return detected providers.
 * Also checks for Ollama at localhost:11434 if reachable.
 */
export function detectProviders(): DetectedProvider[] {
  const found: DetectedProvider[] = [];

  for (const [name, config] of Object.entries(PROVIDER_ENV_MAP)) {
    for (const envKey of config.keys) {
      if (process.env[envKey]) {
        found.push({
          name,
          label: config.label,
          model: config.model,
          envKey,
        });
        break; // Only need one key per provider
      }
    }
  }

  return found;
}

/**
 * Check if Ollama is reachable. Call separately since it's async.
 */
export async function checkOllama(host = 'http://localhost:11434'): Promise<DetectedProvider | null> {
  try {
    const controller = new AbortController();
    const timeout = setTimeout(() => controller.abort(), 1500);
    const res = await fetch(`${host}/api/tags`, { signal: controller.signal });
    clearTimeout(timeout);
    if (res.ok) {
      return { name: 'ollama', label: 'Ollama (Local)', model: 'llama3.2:3b', envKey: '' };
    }
  } catch {
    // Not reachable
  }
  return null;
}

/** Resolve the API key for a provider from env */
export function resolveApiKey(provider: string): string {
  const config = PROVIDER_ENV_MAP[provider];
  if (!config) return '';
  for (const envKey of config.keys) {
    if (process.env[envKey]) return process.env[envKey]!;
  }
  return '';
}