import React, { useReducer } from 'react'

import { getDays } from '../lib/dateHelper'

export const WizardContext = React.createContext()

export const ACTIONS = {
  NEXT_STEP: 'nextStep',
  PREV_STEP: 'prevStep',
  SET_MULTIPLE_DAYS: 'setMultipleDays',
  SET_DATE: 'setDate',
  SET_FOCUSED_INPUT: 'setFocusedInput',
  SET_PICKUP_TIME: 'setPickupTime',
  SET_DROPOFF_TIME: 'setDropoffTime',
  SUBMIT: 'submit',
}

function reducer(state, action) {
  switch (action.type) {
    case ACTIONS.NEXT_STEP:
      return {
        ...state,
        currentStep: state.currentStep + 1, // wizards steps unkown here
      }
    case ACTIONS.PREV_STEP:
      return {
        ...state,
        currentStep: Math.max(0, state.currentStep - 1),
      }
    case ACTIONS.SET_MULTIPLE_DAYS:
      return {
        ...state,
        multipleDays: action.payload,
        focusedInput: undefined,
        startDate: undefined,
        endDate: undefined,
        days: [],
      }
    case ACTIONS.SET_DATE:
      return {
        ...state,
        startDate: action.payload.startDate,
        endDate: action.payload.endDate,
        days: getDays({
          startDate: action.payload.startDate || state.startDate,
          endDate: action.payload.endDate || state.endDate,
          multipleDays: state.multipleDays,
        }),
      }
    case ACTIONS.SET_FOCUSED_INPUT:
      return { ...state, focusedInput: action.payload }
    case ACTIONS.SET_PICKUP_TIME:
      return { ...state, pickupTime: action.payload }
    case ACTIONS.SET_DROPOFF_TIME:
      return { ...state, dropoffTime: action.payload }
    case ACTIONS.SUBMIT:
      // TODO: should probably not kick this off here, that sucks
      createBooking(state)
      return { ...state }
    default:
      throw new Error(`Unkown Action type ${action.type}`)
  }
}

function debugReducer(state, action) {
  console.debug('applying action', action)
  const newState = reducer(state, action)
  console.debug(newState)
  return newState
}

async function createBooking(state) {
  const { name, email, days } = state
  const response = await fetch('/api/booking', {
    method: 'POST',
    mode: 'cors',
    cache: 'no-cache',
    credentials: 'same-origin',
    headers: {
      'Content-Type': 'application/json',
    },
    referrerPolicy: 'no-referrer',
    body: JSON.stringify({ name, email, days }),
  })

  return response.json()
}

const initialState = {
  name: 'Thomas Ruoff',
  email: 'thomasruoff@gmail.com',
  currentStep: 0,
  multipleDays: null,
  bookedOn: [
    '2020-07-10',
    '2020-07-11',
    '2020-07-12',
    '2020-07-23',
    '2020-08-01',
  ],
}

export default function WizardStore({ children }) {
  const [state, dispatch] = useReducer(debugReducer, initialState)

  return (
    <WizardContext.Provider value={{ state, dispatch }}>
      {children}
    </WizardContext.Provider>
  )
}