'use client';

import clsx from 'clsx';
import { useEffect, useRef, useState } from 'react';
import { BiDownload } from 'react-icons/bi';
import { toast } from 'react-toastify';

import Button from '@/components/Common/Button';
import Checkbox from '@/components/Common/Checkbox';
import Label from '@/components/Common/Label';
import MiniButton from '@/components/Common/MiniButton';
import Overlay from '@/components/Common/Overlay';
import SubmitButton from '@/components/Common/SubmitButton';
import TextArea from '@/components/Common/TextArea';
import TextInput from '@/components/Common/TextInput';
import InfoError from '@/components/InfoError';
import RequireAuth from '@/components/RequireAuth';
import { useLibrary } from '@/context/LibraryContext';
import { useConceptNavigation } from '@/context/NavigationContext';
import { LibraryItemType } from '@/models/library';
import { IRSFormCreateData } from '@/models/rsform';
import { classnames, EXTEOR_TRS_FILE, limits, patterns } from '@/utils/constants';

function CreateRSFormPage() {
  const router = useConceptNavigation();
  const { createItem, error, setError, processing } = useLibrary();

  const [title, setTitle] = useState('');
  const [alias, setAlias] = useState('');
  const [comment, setComment] = useState('');
  const [common, setCommon] = useState(false);

  const [fileName, setFileName] = useState('');
  const [file, setFile] = useState<File | undefined>();
  const inputRef = useRef<HTMLInputElement | null>(null);

  useEffect(() => {
    setError(undefined);
  }, [title, alias, setError]);

  function handleCancel() {
    if (router.canBack()) {
      router.back();
    } else {
      router.push('/library');
    }
  }

  function handleSubmit(event: React.FormEvent<HTMLFormElement>) {
    event.preventDefault();
    if (processing) {
      return;
    }
    const data: IRSFormCreateData = {
      item_type: LibraryItemType.RSFORM,
      title: title,
      alias: alias,
      comment: comment,
      is_common: common,
      is_canonical: false,
      file: file,
      fileName: file?.name
    };
    createItem(data, newSchema => {
      toast.success('Схема успешно создана');
      router.push(`/rsforms/${newSchema.id}`);
    });
  }

  function handleFileChange(event: React.ChangeEvent<HTMLInputElement>) {
    if (event.target.files && event.target.files.length > 0) {
      setFileName(event.target.files[0].name);
      setFile(event.target.files[0]);
    } else {
      setFileName('');
      setFile(undefined);
    }
  }

  return (
    <RequireAuth>
      <form className={clsx('px-6 py-3', classnames.flex_col)} onSubmit={handleSubmit}>
        <h1>Создание концептуальной схемы</h1>
        <Overlay position='top-[-2.4rem] right-[-1rem]'>
          <input
            ref={inputRef}
            type='file'
            style={{ display: 'none' }}
            accept={EXTEOR_TRS_FILE}
            onChange={handleFileChange}
          />
          <MiniButton
            title='Загрузить из Экстеор'
            icon={<BiDownload size='1.25rem' className='clr-text-primary' />}
            onClick={() => inputRef.current?.click()}
          />
        </Overlay>
        {fileName ? <Label text={`Загружен файл: ${fileName}`} /> : null}

        <TextInput
          required={!file}
          label='Полное название'
          placeholder={file && 'Загрузить из файла'}
          value={title}
          onChange={event => setTitle(event.target.value)}
        />
        <TextInput
          required={!file}
          label='Сокращение'
          placeholder={file && 'Загрузить из файла'}
          className='w-[14rem]'
          pattern={patterns.library_alias}
          title={`не более ${limits.library_alias_len} символов`}
          value={alias}
          onChange={event => setAlias(event.target.value)}
        />
        <TextArea
          label='Комментарий'
          placeholder={file && 'Загрузить из файла'}
          value={comment}
          onChange={event => setComment(event.target.value)}
        />
        <Checkbox label='Общедоступная схема' value={common} setValue={value => setCommon(value ?? false)} />
        <div className='flex justify-around gap-6 py-3'>
          <SubmitButton text='Создать схему' loading={processing} className='min-w-[10rem]' />
          <Button text='Отмена' className='min-w-[10rem]' onClick={() => handleCancel()} />
        </div>
        {error ? <InfoError error={error} /> : null}
      </form>
    </RequireAuth>
  );
}

export default CreateRSFormPage;