import axios, { AxiosError } from 'axios'
import type {
  QueryResponse,
  Report,
  SearchFilters,
  FeedbackPayload,
  GraphData,
  StreamEvent,
} from '@/types'
import { useAuthStore } from '@/stores/auth'

const API_BASE = import.meta.env.VITE_API_URL || '/api'

const client = axios.create({
  baseURL: API_BASE,
  timeout: 60000,
  headers: {
    'Content-Type': 'application/json',
  },
  withCredentials: true,
})

// Inject the JWT on every request
client.interceptors.request.use((config) => {
  const auth = useAuthStore()
  if (auth.accessToken) {
    config.headers.Authorization = `Bearer ${auth.accessToken}`
  }
  return config
})

// Track rate-limit headers + show the auth modal on 429
client.interceptors.response.use(
  (response) => {
    const auth = useAuthStore()
    auth.updateRateFromHeaders(response.headers as unknown as Headers)
    return response
  },
  (error: AxiosError) => {
    const auth = useAuthStore()

    // Feed any rate headers we DID get back into the store
    if (error.response?.headers) {
      try {
        auth.updateRateFromHeaders(error.response.headers as unknown as Headers)
      } catch {
        // axios headers are not always Headers — that's fine
      }
    }

    if (error.response?.status === 429) {
      // Open the signup modal so the user can convert
      auth.openAuthModal()
      throw new Error('Daily limit reached. Sign up for 25× more queries.')
    }
    if (error.response?.status === 401) {
      // Token rejected — clear it and force re-auth
      auth.$reset?.()
      throw new Error('Your session has expired. Please sign in again.')
    }
    throw error
  }
)

export const api = {
  // Health
  health: () => client.get('/health'),

  // RAG query (non-streaming)
  query: async (
    query: string,
    filters?: SearchFilters,
    language: string = 'en',
    mode: string = 'concise'
  ) => {
    const response = await client.post<QueryResponse>('/query', {
      query,
      language,
      mode,
      filters,
    })
    return response.data
  },

  // Streaming query (SSE)
  queryStream: (
    query: string,
    onEvent: (event: StreamEvent) => void,
    filters?: SearchFilters
  ): EventSource => {
    const auth = useAuthStore()
    const url = new URL(`${API_BASE}/agent/stream`, window.location.origin)

    // EventSource doesn't support custom headers, so we pass the JWT
    // as a query param fallback (the server may ignore if it prefers headers).
    if (auth.accessToken) {
      url.searchParams.set('access_token', auth.accessToken)
    }

    const eventSource = new EventSource(url.toString())

    eventSource.onmessage = (event) => {
      try {
        const data = JSON.parse(event.data)
        onEvent(data)
      } catch {
        onEvent({ event: 'error', data: { message: 'Bad event payload' } })
      }
    }

    eventSource.onerror = () => {
      onEvent({ event: 'error', data: { message: 'Stream connection failed' } })
      eventSource.close()
    }

    return eventSource
  },

  // Documents
  getDocuments: async (params?: {
    auditee?: string
    fy?: string
    limit?: number
    offset?: number
  }) => {
    const response = await client.get<Report[]>('/documents', { params })
    return response.data
  },

  getReport: async (id: string) => {
    const response = await client.get<Report>(`/documents/${id}`)
    return response.data
  },

  // Graph
  graphQuery: async (cypher: string) => {
    const response = await client.post<GraphData>('/graph/query', {
      cypher,
      read_only: true,
    })
    return response.data
  },

  getEntityGraph: async (entityId: string) => {
    const response = await client.get<GraphData>(`/graph/entity/${entityId}`)
    return response.data
  },

  // Feedback
  submitFeedback: async (payload: FeedbackPayload) => {
    const response = await client.post('/feedback', payload)
    return response.data
  },

  // Suggestions
  getSuggestions: async (query: string) => {
    const response = await client.get<string[]>('/suggestions', {
      params: { q: query },
    })
    return response.data
  },
}

export default api