// Theirs
import React from 'react'
import Link from 'next/link'
import Router from 'next/router'
import formatDistanceToNow from 'date-fns/formatDistanceToNow'
import { useAsyncCallback } from '@dawnlabs/tacklebox'

import Button from '../components/Button'
import LoginButton from '../components/LoginButton'
import { useAuth } from '../components/AuthContext'
import { useAPI } from '../components/ApiContext'

import { MetaLinks } from '../components/Meta'
import Carbon from '../components/Carbon'

import { COLORS, DEFAULT_SETTINGS } from '../lib/constants'

// Ours
import Page from '../components/Page'

function correctTimestamp(n) {
  if (n < 9e12) {
    return n * 1000
  }
  return n
}

function Snippet(props) {
  const config = { ...DEFAULT_SETTINGS, ...props, fontSize: '2px', windowControls: false }

  return (
    <Link prefetch={false} href={`/${props.id}`}>
      <a href={`/${props.id}`}>
        <div className="snippet">
          <div className="column">
            <div className="carbon-container">
              <Carbon key={config.language} readOnly={true} config={config} loading={props.loading}>
                {props.code}
              </Carbon>
            </div>
            <div className="id">{props.title || props.id}</div>
            <div className="meta">
              Edited {formatDistanceToNow(correctTimestamp(props.updatedAt), { addSuffix: true })}
            </div>
          </div>
        </div>
        <style jsx>
          {`
            .snippet {
              position: relative;
              width: 266px;
              height: 266px;
              border: 1px solid ${COLORS.SECONDARY};
              border-radius: 3px;
              cursor: pointer !important;
              overflow: hidden;
            }
            .snippet:hover {
              background: ${COLORS.HOVER};
            }
            .snippet:hover:after {
              position: absolute;
              content: '↗';
              display: flex;
              align-items: center;
              justify-content: center;
              background: ${COLORS.HOVER};
              opacity: 0.8;
              top: 0px;
              right: 0px;
              bottom: 0px;
              left: 0px;
              font-size: 48px;
              z-index: 999;
            }
            .column {
              display: flex;
              flex-direction: column;
              justify-content: space-between;
              height: 100%;
              overflow: hidden;
            }
            .id {
              position: absolute;
              top: 0.25rem;
              right: 0.125rem;
              border-radius: 3px;
              background: ${COLORS.SECONDARY};
              color: ${COLORS.BLACK};
              font-size: 10px;
              padding: 0.125rem;
              max-width: 80%;
              text-overflow: ellipsis;
              white-space: nowrap;
              overflow: hidden;
              z-index: 200;
            }
            .carbon-container {
              width: 100%;
              height: 100%;

              overflow: hidden;
              color: ${COLORS.SECONDARY};
              width: 266px;
            }
            .carbon-container :global(.CodeMirror__container .CodeMirror span) {
              font-size: 2px !important;
            }
            .meta {
              background: ${COLORS.SECONDARY};
              color: ${COLORS.DARK_GRAY};
              width: 100%;
              font-size: 10px;
              padding: 0.24rem;
              bottom: 0px;
            }
          `}
        </style>
      </a>
    </Link>
  )
}

function ActionButton(props) {
  return (
    <Button
      border
      center
      margin="0.5rem"
      flex="0 0 266px"
      color={COLORS.GRAY}
      style={{ minHeight: 266 }}
      {...props}
    />
  )
}

function useOnMount() {
  const [mounted, mount] = React.useState(false)
  React.useEffect(() => {
    mount(true)
  }, [])

  return mounted
}

function SnippetsPage() {
  const user = useAuth()
  const api = useAPI()

  const [snippets, setSnippets] = React.useState([])
  const [page, setPage] = React.useState(0)

  const mounted = useOnMount()

  const [loadMore, { loading, data: previousRes }] = useAsyncCallback(api.snippet.list)

  React.useEffect(() => {
    if (user) {
      const authorization = user.ra
      loadMore(page, { authorization }).then(newSnippets =>
        setSnippets(curr => curr.concat(newSnippets))
      )
    }
  }, [loadMore, page, user])

  if (!user) {
    return <LoginButton />
  }

  return (
    <div className="container">
      {snippets.map(snippet => (
        <Snippet key={snippet.id} {...snippet} loading={!mounted} />
      ))}
      {snippets.length && previousRes && previousRes.length < 10 ? null : (
        <ActionButton
          disabled={loading}
          onClick={() => {
            if (snippets.length) return setPage(p => p + 1)

            Router.push('/')
          }}
        >
          <h4>{loading ? 'Loading...' : !snippets.length ? 'Create snippet +' : 'Load more +'}</h4>
        </ActionButton>
      )}
      <style jsx>
        {`
          .container {
            max-width: 872px;
            min-width: ${266 + 32 + 8}px;
            border: 3px solid ${COLORS.SECONDARY};
            border-radius: 8px;
            padding: 0.5rem;
            display: flex;
            flex-wrap: wrap;
          }
          .container :global(.snippet) {
            margin: 0.5rem;
          }
        `}
      </style>
    </div>
  )
}

export default () => (
  <Page enableHeroText={true}>
    <MetaLinks />
    <SnippetsPage />
  </Page>
)