import { PureComponent } from 'react';
import Autocomplete from '@mui/material/Autocomplete';
import Box from '@mui/material/Box';
import Button from '@mui/material/Button';
import Stack from '@mui/material/Stack';
import TextField from '@mui/material/TextField';
import { enqueueSnackbar } from 'notistack';
import BackendError from '../../components/BackendError';
import SingleLineTextEdit from '../../components/SingleLineTextEdit';
import { PanelTile, PanelTileGrid } from '../../components/panels';
import { StorageManagerContext } from '../../api/storageManagerContext';
import { router } from '../../appRouter';
import { requireDefined, requireObject } from '../../utils/apiShape';
import { backendErrorFrom } from '../../utils/backendError';
import { notifyError } from '../../utils/notify';

function sortGroups(groups) {
  return [...groups].sort((a, b) => {
    const bySort = a.sort - b.sort;
    if (bySort !== 0) return bySort;
    const byName = String(a.name).localeCompare(String(b.name), 'de');
    if (byName !== 0) return byName;
    return a.id - b.id;
  });
}

class KundeNeuPage extends PureComponent {
  static contextType = StorageManagerContext;

  constructor(props) {
    super(props);
    this.state = {
      status: 'loading',
      error: null,
      groups: [],
      customergroupId: null,
      name: '',
      firstName: '',
      saving: false,
    };
    this._cancelled = false;
    this.handleRetry = this.handleRetry.bind(this);
    this.handleGroupChange = this.handleGroupChange.bind(this);
    this.handleSave = this.handleSave.bind(this);
  }

  componentDidMount() {
    this._cancelled = false;
    void this.loadGroups();
  }

  componentWillUnmount() {
    this._cancelled = true;
  }

  async loadGroups() {
    this.setState({ status: 'loading', error: null });
    try {
      const list =
        this.context.customergroups ??
        (await this.context.customergroupPromise);
      if (this._cancelled) return;
      this.setState({
        status: 'ready',
        groups: sortGroups(list),
      });
    } catch (err) {
      if (this._cancelled) return;
      this.setState({
        status: 'failed',
        error: backendErrorFrom(err),
      });
    }
  }

  handleRetry() {
    void this.loadGroups();
  }

  handleGroupChange(_event, option) {
    this.setState({ customergroupId: option?.id ?? null });
  }

  async handleSave() {
    if (this.state.saving) return;
    const { customergroupId, name, firstName } = this.state;
    const trimmedName = name.trim();
    const trimmedFirst = firstName.trim();

    if (customergroupId == null) {
      notifyError(new Error('Kundengruppe fehlt.'));
      return;
    }
    if (!trimmedName) {
      notifyError(new Error('Name fehlt.'));
      return;
    }

    const body = {
      customergroupId,
      name: trimmedName,
    };
    if (trimmedFirst) body.firstName = trimmedFirst;

    this.setState({ saving: true });
    try {
      const data = await this.context.entity.create(body);
      requireObject(data, 'POST /api/entity');
      requireObject(data.entity, 'entity');
      requireDefined(data.entity.id, 'entity.id');
      await this.context.updateEntity();
      if (this._cancelled) return;
      enqueueSnackbar('Kunde angelegt.', { variant: 'success' });
      void router.navigate(`/kunde/${data.entity.id}`);
    } catch (err) {
      if (this._cancelled) return;
      notifyError(err);
      this.setState({ saving: false });
    }
  }

  render() {
    const {
      status,
      error,
      groups,
      customergroupId,
      name,
      firstName,
      saving,
    } = this.state;

    if (status === 'failed') {
      return <BackendError error={error} onRetry={this.handleRetry} />;
    }

    const selected =
      groups.find((row) => row.id === customergroupId) ?? null;
    const canSave =
      customergroupId != null && name.trim() !== '' && !saving;

    return (
      <PanelTileGrid>
        <PanelTile wide={2} minHeight={220} color="#bfdbfe" title="Neuer Kunde">
          <Stack spacing={2}>
            <Autocomplete
              size="small"
              options={groups}
              value={selected}
              loading={status === 'loading'}
              disabled={saving || status === 'loading'}
              getOptionLabel={(option) => String(option.name ?? '')}
              isOptionEqualToValue={(option, value) => option.id === value.id}
              onChange={this.handleGroupChange}
              renderInput={(params) => (
                <TextField
                  {...params}
                  label="Kundengruppe"
                  required
                  slotProps={{
                    ...params.slotProps,
                    htmlInput: {
                      ...params.slotProps?.htmlInput,
                      spellCheck: false,
                      autoComplete: 'off',
                    },
                  }}
                />
              )}
            />
            <SingleLineTextEdit
              size="small"
              label="Name"
              required
              value={name}
              disabled={saving}
              onChange={(next) => this.setState({ name: next })}
            />
            <SingleLineTextEdit
              size="small"
              label="Vorname"
              value={firstName}
              disabled={saving}
              onChange={(next) => this.setState({ firstName: next })}
            />
            <Box sx={{ display: 'flex', justifyContent: 'flex-end' }}>
              <Button
                variant="contained"
                size="small"
                disabled={!canSave}
                onClick={() => void this.handleSave()}
              >
                {saving ? 'Speichern…' : 'Speichern'}
              </Button>
            </Box>
          </Stack>
        </PanelTile>
      </PanelTileGrid>
    );
  }
}

export default KundeNeuPage;