import type { CospendProject, Group, Item, Member, Receipt, SubmitResult } from './types'

const BASE = import.meta.env.VITE_API_BASE_URL ?? ''

async function req<T>(path: string, init?: RequestInit): Promise<T> {
  const res = await fetch(`${BASE}/api${path}`, {
    ...init,
    headers: init?.body instanceof FormData ? init.headers : { 'Content-Type': 'application/json', ...init?.headers },
  })
  if (!res.ok) {
    const body = await res.json().catch(() => ({}))
    throw new Error(body.error || `${res.status} ${res.statusText}`)
  }
  return res.json()
}

export const api = {
  uploadReceipt(
    file: File | Blob,
  ): Promise<{ id: string; items: Item[]; store_name: string | null; date: string }> {
    const form = new FormData()
    form.append('image', file, 'receipt.jpg')
    return req('/receipts', { method: 'POST', body: form })
  },

  getReceipt(id: string): Promise<Receipt> {
    return req(`/receipts/${id}`)
  },

  updateItems(id: string, items: Item[]): Promise<Receipt> {
    return req(`/receipts/${id}/items`, { method: 'PATCH', body: JSON.stringify({ items }) })
  },

  updateMeta(id: string, meta: { store_name?: string; date?: string }): Promise<Receipt> {
    return req(`/receipts/${id}/meta`, { method: 'PATCH', body: JSON.stringify(meta) })
  },

  getProjects(): Promise<{ projects: CospendProject[]; default_project_id: string | null }> {
    return req('/cospend/projects')
  },

  getMembers(projectId: string): Promise<Member[]> {
    return req(`/cospend/projects/${projectId}/members`)
  },

  createGroup(
    receiptId: string,
    group: {
      name: string
      cospend_project_id: string
      payer_member_id: string
      member_ids: string[]
      item_ids: string[]
    },
  ): Promise<{ id: string }> {
    return req(`/receipts/${receiptId}/groups`, { method: 'POST', body: JSON.stringify(group) })
  },

  submitGroup(receiptId: string, groupId: string): Promise<SubmitResult> {
    return req(`/receipts/${receiptId}/groups/${groupId}/submit`, { method: 'POST' })
  },

  listGroups(receiptId: string): Promise<Group[]> {
    return req(`/receipts/${receiptId}/groups`)
  },
}