import React, { ReactElement, useEffect } from 'react'
import { withStyles, Theme, createStyles } from '@material-ui/core/styles'
import { Tabs, Tab, Box, Typography } from '@material-ui/core'
import CodeBlock from './CodeBlock'

interface TabPanelProps {
  children?: React.ReactNode
  index: number
  value: number
}

interface Props {
  linux: string
  mac: string
  showLineNumbers?: boolean
}

function a11yProps(index: number) {
  return {
    id: `simple-tab-${index}`,
    'aria-controls': `simple-tabpanel-${index}`,
  }
}

function getOS() {
  const userAgent = window.navigator.userAgent
  const platform = window.navigator.platform
  const macosPlatforms = ['Macintosh', 'MacIntel', 'MacPPC', 'Mac68K']
  const windowsPlatforms = ['Win32', 'Win64', 'Windows', 'WinCE']
  const iosPlatforms = ['iPhone', 'iPad', 'iPod']

  if (macosPlatforms.includes(platform)) return 'macOS'

  if (iosPlatforms.includes(platform)) return 'iOS'

  if (windowsPlatforms.includes(platform)) return 'windows'

  if (/Android/.test(userAgent)) return 'android'

  if (/Linux/.test(platform)) return 'linux'

  return null
}

export default function CodeBlockTabs(props: Props): ReactElement {
  const [value, setValue] = React.useState(0)

  const handleChange = (event: React.ChangeEvent<unknown>, newValue: number) => {
    setValue(newValue)
  }

  useEffect(() => {
    const os = getOS()

    if (os === 'windows') {
      setValue(0)
    } else if (os === 'linux') {
      setValue(0)
    } else if (os === 'macOS') {
      setValue(1)
    }
  }, [])

  function TabPanel(props: TabPanelProps) {
    const { children, value, index, ...other } = props

    return (
      <div
        role="tabpanel"
        hidden={value !== index}
        id={`simple-tabpanel-${index}`}
        aria-labelledby={`simple-tab-${index}`}
        {...other}
      >
        {value === index && (
          <Box style={{ marginTop: '-12px' }}>
            <Typography component="div">{children}</Typography>
          </Box>
        )}
      </div>
    )
  }

  const AntTabs = withStyles({
    root: {
      borderBottom: '1px solid #e8e8e8',
    },
    indicator: {
      backgroundColor: '#3f51b5',
    },
  })(Tabs)

  interface StyledTabProps {
    label: string
  }

  const AntTab = withStyles((theme: Theme) =>
    createStyles({
      root: {
        textTransform: 'none',
        minWidth: 72,
        backgroundColor: 'transparent',
        fontWeight: theme.typography.fontWeightRegular,
        marginRight: theme.spacing(4),
        fontFamily: [
          '-apple-system',
          'BlinkMacSystemFont',
          '"Segoe UI"',
          'Roboto',
          '"Helvetica Neue"',
          'Arial',
          'sans-serif',
          '"Apple Color Emoji"',
          '"Segoe UI Emoji"',
          '"Segoe UI Symbol"',
        ].join(','),
        '&:hover': {
          color: '#3f51b5',
          opacity: 1,
        },
        '&$selected': {
          color: '#3f51b5',
          fontWeight: theme.typography.fontWeightMedium,
        },
        '&:focus': {
          color: '#3f51b5',
        },
      },
      selected: {},
    }),
  )((props: StyledTabProps) => <Tab disableRipple {...props} />)

  return (
    <div>
      <AntTabs style={{ marginTop: '12px' }} value={value} onChange={handleChange} aria-label="ant example">
        <AntTab label="Linux" {...a11yProps(0)} />
        <AntTab label="MacOS" {...a11yProps(1)} />
      </AntTabs>
      <TabPanel value={value} index={0}>
        <CodeBlock showLineNumbers={props.showLineNumbers} language="bash" code={props.linux} />
      </TabPanel>
      <TabPanel value={value} index={1}>
        <CodeBlock showLineNumbers={props.showLineNumbers} language="bash" code={props.mac} />
      </TabPanel>
    </div>
  )
}