/**
 * Model fetcher — retrieves available models from each provider's API.
 *
 * Each function returns a sorted list of model IDs.
 * Network errors return empty arrays (non-fatal).
 */

export interface ModelInfo {
  id: string;
  name: string;
  provider: string;
}

const TIMEOUT = 8000;

export async function fetchClaudeModels(): Promise<ModelInfo[]> {
  const apiKey = process.env.ANTHROPIC_API_KEY;
  if (!apiKey) return [];
  try {
    const res = await fetch('https://api.anthropic.com/v1/models', {
      headers: {
        'x-api-key': apiKey,
        'anthropic-version': '2023-06-01',
      },
      signal: AbortSignal.timeout(TIMEOUT),
    });
    if (!res.ok) return [];
    const data = await res.json() as { data?: Array<{ id: string; display_name?: string }> };
    return (data.data ?? [])
      .map(m => ({ id: m.id, name: m.display_name ?? m.id, provider: 'claude' }))
      .sort((a, b) => a.id.localeCompare(b.id));
  } catch {
    return [];
  }
}

export async function fetchCodexModels(): Promise<ModelInfo[]> {
  const apiKey = process.env.OPENAI_API_KEY;
  if (!apiKey) return [];
  try {
    const res = await fetch('https://api.openai.com/v1/models', {
      headers: { 'Authorization': `Bearer ${apiKey}` },
      signal: AbortSignal.timeout(TIMEOUT),
    });
    if (!res.ok) return [];
    const data = await res.json() as { data?: Array<{ id: string }> };
    return (data.data ?? [])
      .map(m => ({ id: m.id, name: m.id, provider: 'codex' }))
      .sort((a, b) => a.id.localeCompare(b.id));
  } catch {
    return [];
  }
}

export async function fetchOllamaModels(): Promise<ModelInfo[]> {
  try {
    const res = await fetch('http://localhost:11434/api/tags', {
      signal: AbortSignal.timeout(TIMEOUT),
    });
    if (!res.ok) return [];
    const data = await res.json() as { models?: Array<{ name: string; model?: string }> };
    return (data.models ?? [])
      .map(m => ({ id: m.name, name: m.name, provider: 'ollama' }))
      .sort((a, b) => a.id.localeCompare(b.id));
  } catch {
    return [];
  }
}

export async function fetchGeminiModels(): Promise<ModelInfo[]> {
  const apiKey = process.env.GEMINI_API_KEY;
  if (!apiKey) return [];
  try {
    const res = await fetch(
      `https://generativelanguage.googleapis.com/v1beta/models?key=${apiKey}`,
      { signal: AbortSignal.timeout(TIMEOUT) },
    );
    if (!res.ok) return [];
    const data = await res.json() as {
      models?: Array<{ name: string; displayName?: string }>;
    };
    return (data.models ?? [])
      .map(m => ({
        id: m.name.replace('models/', ''),
        name: m.displayName ?? m.name,
        provider: 'gemini',
      }))
      .sort((a, b) => a.id.localeCompare(b.id));
  } catch {
    return [];
  }
}

/**
 * Fetch models for a specific provider.
 */
export async function fetchModelsForProvider(
  provider: string,
): Promise<ModelInfo[]> {
  switch (provider) {
    case 'claude': return fetchClaudeModels();
    case 'codex': return fetchCodexModels();
    case 'ollama': return fetchOllamaModels();
    case 'gemini': return fetchGeminiModels();
    default: return [];
  }
}