import { Component } from 'react';
import Alert from '@mui/material/Alert';
import Box from '@mui/material/Box';
import Button from '@mui/material/Button';
import CircularProgress from '@mui/material/CircularProgress';
import Dialog from '@mui/material/Dialog';
import DialogContent from '@mui/material/DialogContent';
import DialogTitle from '@mui/material/DialogTitle';
import Divider from '@mui/material/Divider';
import FormControl from '@mui/material/FormControl';
import FormLabel from '@mui/material/FormLabel';
import InputAdornment from '@mui/material/InputAdornment';
import List from '@mui/material/List';
import ListItemButton from '@mui/material/ListItemButton';
import ListItemText from '@mui/material/ListItemText';
import Stack from '@mui/material/Stack';
import TextField from '@mui/material/TextField';
import ToggleButton from '@mui/material/ToggleButton';
import ToggleButtonGroup from '@mui/material/ToggleButtonGroup';
import Typography from '@mui/material/Typography';
import BusinessIcon from '@mui/icons-material/Business';
import BackendError from './BackendError';
import { company } from '../api';
import { StorageManagerContext } from '../api/storageManagerContext';
import authAutomat from '../automats/authAutomat';
import {
  defaultIso639,
  ISO639_OPTIONS,
  parseTaxRate,
} from '../utils/companyForm';
import { backendErrorFrom, isBackendFailure } from '../utils/backendError';

class CompanySetupDialog extends Component {
  static contextType = StorageManagerContext;

  constructor(props) {
    super(props);
    this.state = {
      companies: [],
      loading: true,
      busy: false,
      error: null,
      name: '',
      iso639: defaultIso639(),
      taxrate: '19',
      reducedtaxrate: '7',
    };
    this.handleSelect = this.handleSelect.bind(this);
    this.handleCreate = this.handleCreate.bind(this);
    this.handleLogout = this.handleLogout.bind(this);
    this.handleClose = this.handleClose.bind(this);
  }

  componentDidMount() {
    void this.loadCompanies();
  }

  async loadCompanies() {
    this.setState({ loading: true });
    try {
      const data = await company.list();
      this.setState({ companies: data.companies ?? [] });
    } catch {
      this.setState({ companies: [] });
    } finally {
      this.setState({ loading: false });
    }
  }

  async handleSelect(companyId) {
    this.setState({ busy: true, error: null });
    try {
      await authAutomat.actions.selectCompany(companyId);
      await this.context.updateAuthMe();
    } catch (err) {
      this.setState({ error: backendErrorFrom(err) });
    } finally {
      this.setState({ busy: false });
    }
  }

  async handleCreate(event) {
    event.preventDefault();
    const { name, iso639, taxrate, reducedtaxrate } = this.state;
    const parsedTaxrate = parseTaxRate(taxrate);
    const parsedReducedtaxrate = parseTaxRate(reducedtaxrate);
    const canCreate =
      name.trim() !== '' &&
      ISO639_OPTIONS.includes(iso639) &&
      parsedTaxrate != null &&
      parsedReducedtaxrate != null;

    if (!canCreate) {
      this.setState({ error: 'Bitte alle Pflichtfelder ausfüllen.' });
      return;
    }

    this.setState({ busy: true, error: null });
    try {
      await authAutomat.actions.createCompany({
        name: name.trim(),
        iso639,
        taxrate: parsedTaxrate,
        reducedtaxrate: parsedReducedtaxrate,
      });
      await this.context.updateAuthMe();
      await this.context.updateCompany();
    } catch (err) {
      this.setState({ error: backendErrorFrom(err) });
    } finally {
      this.setState({ busy: false });
    }
  }

  async handleLogout() {
    try {
      await authAutomat.actions.logout();
      await this.context.updateAuthMe();
    } catch (err) {
      this.setState({ error: backendErrorFrom(err) });
    }
  }

  handleClose(_event, reason) {
    if (reason === 'backdropClick' || reason === 'escapeKeyDown') return;
  }

  render() {
    const { companies, loading, busy, error, name, iso639, taxrate, reducedtaxrate } =
      this.state;
    const hasCompanies = companies.length > 0;
    const parsedTaxrate = parseTaxRate(taxrate);
    const parsedReducedtaxrate = parseTaxRate(reducedtaxrate);
    const canCreate =
      name.trim() !== '' &&
      ISO639_OPTIONS.includes(iso639) &&
      parsedTaxrate != null &&
      parsedReducedtaxrate != null;

    return (
      <Dialog open onClose={this.handleClose} maxWidth="sm" fullWidth>
        <DialogTitle>
          {loading
            ? 'Unternehmen'
            : hasCompanies
              ? 'Unternehmen auswählen'
              : 'Unternehmen anlegen'}
        </DialogTitle>
        <DialogContent>
          {!loading ? (
            <Typography variant="body2" color="text.secondary" sx={{ mb: 2 }}>
              {hasCompanies
                ? 'Wählen Sie ein bestehendes Unternehmen oder legen Sie ein neues an.'
                : 'Legen Sie Ihr Unternehmen an, um fortzufahren.'}
            </Typography>
          ) : null}

          {error ? (
            isBackendFailure(error) ? (
              <BackendError error={error} sx={{ mb: 2 }} />
            ) : (
              <Alert severity="error" sx={{ mb: 2 }}>
                {typeof error === 'string' ? error : error.message}
              </Alert>
            )
          ) : null}

          {loading ? (
            <Box sx={{ display: 'flex', justifyContent: 'center', py: 4 }}>
              <CircularProgress />
            </Box>
          ) : (
            <Stack spacing={3}>
              {hasCompanies ? (
                <Box>
                  <List disablePadding sx={{ bgcolor: 'background.paper', borderRadius: 1 }}>
                    {companies.map((item) => (
                      <ListItemButton
                        key={item.id}
                        disabled={busy}
                        onClick={() => this.handleSelect(item.id)}
                      >
                        <BusinessIcon sx={{ mr: 1.5, color: 'primary.main' }} />
                        <ListItemText primary={item.name} />
                      </ListItemButton>
                    ))}
                  </List>
                </Box>
              ) : null}

              {hasCompanies ? <Divider>oder</Divider> : null}

              <Box component="form" onSubmit={this.handleCreate} noValidate>
                <Stack spacing={2}>
                  {hasCompanies ? (
                    <Typography variant="subtitle2">Neues Unternehmen anlegen</Typography>
                  ) : null}

                  <TextField
                    fullWidth
                    required
                    size="small"
                    label="Name"
                    value={name}
                    disabled={busy}
                    onChange={(e) => this.setState({ name: e.target.value })}
                    autoComplete="organization"
                    autoFocus={!hasCompanies}
                  />

                  <FormControl required>
                    <FormLabel sx={{ mb: 0.5 }}>Sprache</FormLabel>
                    <ToggleButtonGroup
                      exclusive
                      required
                      size="small"
                      value={iso639}
                      disabled={busy}
                      onChange={(_event, value) => {
                        if (value) this.setState({ iso639: value });
                      }}
                    >
                      <ToggleButton value="de">Deutsch</ToggleButton>
                      <ToggleButton value="en">English</ToggleButton>
                    </ToggleButtonGroup>
                  </FormControl>

                  <Stack direction="row" spacing={1}>
                    <TextField
                      fullWidth
                      required
                      size="small"
                      type="number"
                      label="Normalsatz"
                      value={taxrate}
                      disabled={busy}
                      onChange={(e) => this.setState({ taxrate: e.target.value })}
                      error={taxrate !== '' && parsedTaxrate == null}
                      slotProps={{
                        input: {
                          endAdornment: <InputAdornment position="end">%</InputAdornment>,
                        },
                        htmlInput: { min: 0, max: 100, step: 0.01, required: true },
                      }}
                    />
                    <TextField
                      fullWidth
                      required
                      size="small"
                      type="number"
                      label="Ermäßigter Satz"
                      value={reducedtaxrate}
                      disabled={busy}
                      onChange={(e) => this.setState({ reducedtaxrate: e.target.value })}
                      error={reducedtaxrate !== '' && parsedReducedtaxrate == null}
                      slotProps={{
                        input: {
                          endAdornment: <InputAdornment position="end">%</InputAdornment>,
                        },
                        htmlInput: { min: 0, max: 100, step: 0.01, required: true },
                      }}
                    />
                  </Stack>

                  <Button type="submit" variant="contained" disabled={busy || !canCreate}>
                    Anlegen
                  </Button>
                </Stack>
              </Box>

              <Button
                type="button"
                variant="text"
                color="inherit"
                disabled={busy}
                onClick={this.handleLogout}
                sx={{ alignSelf: 'center' }}
              >
                Abmelden
              </Button>
            </Stack>
          )}
        </DialogContent>
      </Dialog>
    );
  }
}

export default CompanySetupDialog;