import React, { Fragment } from 'react';
import { useDispatch, useSelector } from 'react-redux';
import { makeStyles } from '@material-ui/core/styles';
import Avatar from '@material-ui/core/Avatar';
import Divider from '@material-ui/core/Divider';
import List from '@material-ui/core/List';
import ListItem from '@material-ui/core/ListItem';
import ListItemAvatar from '@material-ui/core/ListItemAvatar';
import ListItemSecondaryAction from '@material-ui/core/ListItemSecondaryAction';
import Grid from '@material-ui/core/Grid';
import ListItemText from '@material-ui/core/ListItemText';
import { FixedSizeList } from 'react-window';
import AutoSizer from 'react-virtualized-auto-sizer';
import BatteryFullIcon from '@material-ui/icons/BatteryFull';
import VpnKeyIcon from '@material-ui/icons/VpnKey';

import { devicesActions } from './store';
import EditCollectionView from './EditCollectionView';
import { useEffectAsync } from './reactHelper';
import { formatPosition } from './common/formatter';

const useStyles = makeStyles(theme => ({
  list: {
    maxHeight: '100%',
  },
  icon: {
    width: '25px',
    height: '25px',
    filter: 'brightness(0) invert(1)',
  },
  batteryText: {
    fontSize: '0.75rem',
    fontWeight: 'normal',
    lineHeight: '0.875rem'
  },
  green: {
    color: theme.palette.common.green,
  },
  red: {
    color: theme.palette.common.red,
  },
  gray: {
    color: theme.palette.common.gray
  }
}));

const OnlineStatus =({ status }) => {
  
  const classes = useStyles();

  switch (status) {
    case 'online':
      return <span className={classes.green}>{status}</span>
    case 'offline':
      return <span className={classes.red}>{status}</span>
    case 'unknown':
    default:
      return <span className={classes.gray}>{status}</span>
  }
}

const DeviceStatus = ({ deviceId }) => {
  const classes = useStyles();
  let batteryClass = '';
  
  const position = useSelector(state => state.positions.items[deviceId]);
  if (!position) {
    return null;
  }
  const batteryLevel = position.attributes.hasOwnProperty('batteryLevel') ? position.attributes.batteryLevel : 'undefined';

  if (batteryLevel >= 70) {
    batteryClass = classes.green;
  } else if (batteryLevel > 30) {
    batteryClass = classes.gray;
  } else {
    batteryClass = classes.red;
  }
  return (
    <Grid container direction="row" alignItems="center" alignContent="center" spacing={1}>
      {position.attributes.hasOwnProperty('ignition') && <Grid item>
        <VpnKeyIcon className={`${position.attributes.ignition ? classes.green : classes.gray}`}/>
      </Grid>}
      {batteryLevel !== 'undefined' && <Grid item container xs alignItems="center" alignContent="center">
        <Grid item> 
          <span className={classes.batteryText}>{formatPosition(batteryLevel, 'batteryLevel')}</span>
        </Grid>      
        <Grid item> 
          <BatteryFullIcon className={batteryClass} />
        </Grid>
      </Grid>}
    </Grid>
  );
}

const DeviceRow = ({ data, index, style }) => {
  const classes = useStyles();
  const dispatch = useDispatch();

  const { items, onMenuClick } = data;
  const item = items[index];

  return (
    <div style={style}>
      <Fragment key={index}>
        <ListItem button key={item.id} onClick={() => dispatch(devicesActions.select(item))}>
          <ListItemAvatar>
            <Avatar>
              <img className={classes.icon} src={`images/icon/${item.category || 'default'}.svg`} alt="" />
            </Avatar>
          </ListItemAvatar>
          <ListItemText primary={item.name} secondary={<OnlineStatus status={item.status} />} />
          <ListItemSecondaryAction>
            <DeviceStatus deviceId={item.id} />
          </ListItemSecondaryAction>
        </ListItem>
        {index < items.length - 1 ? <Divider /> : null}
      </Fragment>
    </div>
  );
};

const DeviceView = ({ updateTimestamp, onMenuClick }) => {
  const classes = useStyles();
  const dispatch = useDispatch();

  const items = useSelector((state) => Object.values(state.devices.items));

  useEffectAsync(async () => {
    const response = await fetch('/api/devices');
    if (response.ok) {
      dispatch(devicesActions.refresh(await response.json()));
    }
  }, [updateTimestamp]);

  return (
    <AutoSizer className={classes.list}>
      {({ height, width }) => (
        <List disablePadding>
          <FixedSizeList
            width={width}
            height={height}
            itemCount={items.length}
            itemData={{ items, onMenuClick }}
            itemSize={72 + 1}
          >
            {DeviceRow}
          </FixedSizeList>
        </List>
      )}
    </AutoSizer>
  );
};

const DevicesList = () => (
  <EditCollectionView content={DeviceView} editPath="/device" endpoint="devices" />
);

export default DevicesList;