import {useState} from 'react'

import Link from 'next/link'
import AdminToolbar from '~/components/admin/actionBar'
import {Button as RButton} from '@rmwc/button'
import {FormController, Input, IntegerInput, Button} from '~/components/form'
import Table from '~/components/table'
import axios from 'axios'
import router from 'next/router'

NewShipment.getInitialProps = async ({ctx: {axios}}) => {
  const {data: allItems} = await axios.get('/api/items')
  return {allItems}
}

export default function NewShipment({allItems}){
  const [currentView, setView] = useState('description')
  const [description, setDescription] = useState()
  const [items,       setItems] = useState([])
  const [currentItem, setCurrentItem] = useState()

  const currentUUIDs = items.map(({item}) => item.uuid)
  const addableItems = allItems.filter(({uuid}) => !currentUUIDs.includes(uuid))

  const handleRemoveItem = item => {
    setItems(items => items.filter(listItem => item.uuid !== listItem.item.uuid))
  }

  const handleAddItem = ({count}) => {
    const newItem = {
      count,
      item: currentItem
    }

    setCurrentItem(null)

    setItems(items => [...items.filter(listItem => currentItem.uuid !== listItem.item.uuid), newItem])
    setView('summary')
  }

  const saveShipment = async () => {
    const {data: shipment} = await axios.post('/api/shipments', {
      description,
      items: items.map(listItem => ({count: listItem.count, uuid: listItem.item.uuid}))
    })

    router.push(`/admin/shipments/${shipment.uuid}`)
  }

  switch(currentView){
    case 'description':
      return (
        <>
          <AdminToolbar title="Add Shipment"/>
          <Link href={`/admin/shipments`}><a><RButton icon="arrow_left">Cancel Shipment</RButton></a></Link>
          <FormController afterSubmit={({description}) => {setDescription(description); setView('summary')}}>
            <h2>Set shipment description</h2>
            <Input label="Description" type="text" name="description" initialValue={description || undefined} validate={value=>value.length > 0} hint="Enter a shipment description" />
            <Button type="submit">Next</Button>
          </FormController>
        </>
      )

    case 'summary':
      return (
        <>
          <AdminToolbar title={`Add Shipment`}/>
          <div style={{margin: '0 16px', marginBottom: '16px', display: 'flex', flexDirection: 'row', justifyContent: 'space-between'}}>
            <RButton icon="arrow_left" onClick={()=>setView('description')}>Edit Description</RButton>
            <RButton icon="add" onClick={() => setView('selectItem')}>Add Item</RButton>
          </div>
          <Table
            columns={[
              {name: 'Item', extractor: item => item.item.name},
              {name: 'Count', extractor: item => item.count},
              {name: '', extractor: ({item}) => (
                <span>
                  <button onClick={()=>{setCurrentItem(item); setView('addItem')}} className="buttonLink">Adjust count</button>
                  <button onClick={()=>{handleRemoveItem(item)}} className="buttonLink">Remove</button>
                </span>
              )}
            ]}
            // Map in an id property so the table can use array.map
            rows={items.map(listItem => ({...listItem, id: listItem.item.uuid}))}
          />

          <FormController afterSubmit={saveShipment}>
            <Button enabled={items.length > 0}>Create Shipment</Button>
          </FormController>
        </>
      )

    case 'selectItem':
      return (
        <>
          <AdminToolbar title={`Add Shipment`}/>

          <div style={{margin: '0 16px', display: 'flex', flexDirection: 'row', justifyContent: 'space-between'}}>
            <RButton icon="arrow_left" onClick={()=>setView('summary')}>Cancel Adding Item</RButton>
          </div>

          <h2 style={{textAlign: 'center'}}>Select Item</h2>
          <Table
            columns={[
              {name: 'Name', extractor: item => item.name},
              {name: '', extractor: item => (
                <span>
                  <button onClick={()=>{setCurrentItem(item); setView('addItem')}} className="buttonLink">Use this item</button>
                </span>
              )}
            ]}

            rows={addableItems}
          />
        </>
      )

    case 'addItem':
      if(currentItem === null){
        setView('selectItem')
        return null
      }

      const currentValue = items.find(listItem => currentItem.uuid === listItem.item.uuid)?.count

      return (
        <>
          <AdminToolbar title={`Add Shipment`}/>

          <div style={{margin: '0 16px', display: 'flex', flexDirection: 'row', justifyContent: 'space-between'}}>
            <RButton icon="arrow_left" onClick={()=>setView('summary')}>Cancel Adding Item</RButton>
          </div>

          <FormController afterSubmit={handleAddItem}>
            <h2 style={{textAlign: 'center'}}>{currentValue !== undefined ? 'Adjust Item' : 'Add Item'}</h2>
            <p>How many of &ldquo;{currentItem.name}&rdquo; are in this shipment?</p>
            <IntegerInput initialValue={currentValue || 1} label="Count" name="count" minimum={1}/>
            <Button type="submit">Add Item</Button>
          </FormController>
        </>
      )


    default:
      return (
        <>
          <AdminToolbar title="Add Shipment"/>
          <Link href={`/admin/shipments`}><a><RButton icon="arrow_left">Cancel Shipment</RButton></a></Link>
          <p>An error occurred trying to create this shipment.  Please refresh the page.</p>
        </>
      )
  }
}