import type {
  ChatMessage,
  ChatResponse,
  ImageResponse,
  ModelsResponse,
  StatsResponse,
  HealthResponse,
  AuthConfig,
  AuthResponse,
  AuthUser,
} from './types'

const BASE_URL = '/api'

// ---------------------------------------------------------------------------
// Token management
// ---------------------------------------------------------------------------

const TOKEN_KEY = 'lp_auth_token'

export function getToken(): string | null {
  return localStorage.getItem(TOKEN_KEY)
}

export function setToken(token: string) {
  localStorage.setItem(TOKEN_KEY, token)
}

export function clearToken() {
  localStorage.removeItem(TOKEN_KEY)
}

function authHeaders(): Record<string, string> {
  const token = getToken()
  return token ? { Authorization: `Bearer ${token}` } : {}
}

// ---------------------------------------------------------------------------
// Generic request helper
// ---------------------------------------------------------------------------

async function request<T>(path: string, options?: RequestInit): Promise<T> {
  const res = await fetch(`${BASE_URL}${path}`, {
    headers: { 'Content-Type': 'application/json', ...authHeaders() },
    ...options,
  })
  if (!res.ok) {
    const err = await res.json().catch(() => ({ detail: res.statusText }))
    throw new Error(err.detail || `HTTP ${res.status}`)
  }
  return res.json()
}

// ---------------------------------------------------------------------------
// Auth
// ---------------------------------------------------------------------------

export async function getAuthConfig(): Promise<AuthConfig> {
  return request('/auth/config')
}

export async function loginWithGoogle(credential: string): Promise<AuthResponse> {
  return request('/auth/google', {
    method: 'POST',
    body: JSON.stringify({ credential }),
  })
}

export async function getMe(): Promise<AuthUser> {
  return request('/auth/me')
}

// ---------------------------------------------------------------------------
// Public API
// ---------------------------------------------------------------------------

export async function getHealth(): Promise<HealthResponse> {
  return request('/health')
}

export async function getModels(): Promise<ModelsResponse> {
  return request('/models')
}

export async function getStats(): Promise<StatsResponse> {
  return request('/stats')
}

// ---------------------------------------------------------------------------
// Protected API
// ---------------------------------------------------------------------------

export async function sendChat(
  message: string,
  model: string,
  history: ChatMessage[],
  lang: string = 'hr',
): Promise<ChatResponse> {
  return request('/chat', {
    method: 'POST',
    body: JSON.stringify({
      message,
      model,
      lang,
      history: history.map((m) => ({ role: m.role, content: m.content })),
    }),
  })
}

export async function analyzeImage(
  imageFile: File,
  question: string,
  model: string,
): Promise<ImageResponse> {
  const formData = new FormData()
  formData.append('image', imageFile)
  formData.append('question', question)
  formData.append('model', model)

  const res = await fetch(`${BASE_URL}/analyze-image`, {
    method: 'POST',
    body: formData,
    headers: authHeaders(),
  })
  if (!res.ok) {
    const err = await res.json().catch(() => ({ detail: res.statusText }))
    throw new Error(err.detail || `HTTP ${res.status}`)
  }
  return res.json()
}