/**
 * Composable for API calls to the FastAPI backend.
 */
export function useApi() {
  const config = useRuntimeConfig()
  const baseURL = config.public.apiBase as string

  function getToken(): string | null {
    if (import.meta.client) {
      return localStorage.getItem('sejeteralo_token')
    }
    return null
  }

  async function apiFetch<T>(
    path: string,
    options: RequestInit = {},
  ): Promise<T> {
    const headers: Record<string, string> = {
      ...(options.headers as Record<string, string> || {}),
    }

    const token = getToken()
    if (token) {
      headers['Authorization'] = `Bearer ${token}`
    }

    if (options.body && !(options.body instanceof FormData)) {
      headers['Content-Type'] = 'application/json'
    }

    let response: Response
    try {
      response = await fetch(`${baseURL}${path}`, {
        ...options,
        headers,
      })
    } catch (err) {
      throw new Error(`Impossible de contacter le serveur (${baseURL}). Vérifiez que le backend est lancé.`)
    }

    if (!response.ok) {
      const error = await response.json().catch(() => ({ detail: response.statusText }))
      throw new Error(error.detail || `Erreur API ${response.status}`)
    }

    const text = await response.text()
    if (!text) return {} as T
    return JSON.parse(text)
  }

  return {
    get: <T>(path: string) => apiFetch<T>(path),
    post: <T>(path: string, body?: unknown) =>
      apiFetch<T>(path, {
        method: 'POST',
        body: body instanceof FormData ? body : JSON.stringify(body),
      }),
    put: <T>(path: string, body?: unknown) =>
      apiFetch<T>(path, {
        method: 'PUT',
        body: JSON.stringify(body),
      }),
    delete: <T>(path: string) =>
      apiFetch<T>(path, { method: 'DELETE' }),
  }
}