import React, { FormEvent } from 'react'
import {MdFileUpload} from 'react-icons/md'
import {MdAddCircleOutline} from 'react-icons/md'
import FileReaderInput, { Result } from 'react-file-reader-input'

import ModalLoading from './ModalLoading'
import Modal from './Modal'
import InputButton from './InputButton'
import InputUrl from './InputUrl'

import style from '../libs/style'
import publicStyles from '../config/styles.json'

type PublicStyleProps = {
  url: string
  thumbnailUrl: string
  title: string
  onSelect(...args: unknown[]): unknown
};

class PublicStyle extends React.Component<PublicStyleProps> {
  render() {
    return <div className="maputnik-public-style">
      <InputButton
        className="maputnik-public-style-button"
        aria-label={this.props.title}
        onClick={() => this.props.onSelect(this.props.url)}
      >
        <div className="maputnik-public-style-header">
          <div>{this.props.title}</div>
          <span className="maputnik-space" />
          <MdAddCircleOutline />
        </div>
        <div
          className="maputnik-public-style-thumbnail"
          style={{
            backgroundImage: `url(${this.props.thumbnailUrl})`
          }}
        ></div>
      </InputButton>
    </div>
  }
}

type ModalOpenProps = {
  isOpen: boolean
  onOpenToggle(...args: unknown[]): unknown
  onStyleOpen(...args: unknown[]): unknown
};

type ModalOpenState = {
  styleUrl: string
  error?: string | null
  activeRequest?: any
  activeRequestUrl?: string | null
};

export default class ModalOpen extends React.Component<ModalOpenProps, ModalOpenState> {
  constructor(props: ModalOpenProps) {
    super(props);
    this.state = {
      styleUrl: ""
    };
  }

  clearError() {
    this.setState({
      error: null
    })
  }

  onCancelActiveRequest(e: Event) {
    // Else the click propagates to the underlying modal
    if(e) e.stopPropagation();

    if(this.state.activeRequest) {
      this.state.activeRequest.abort();
      this.setState({
        activeRequest: null,
        activeRequestUrl: null
      });
    }
  }

  onStyleSelect = (styleUrl: string) => {
    this.clearError();

    let canceled: boolean = false;

    fetch(styleUrl, {
      mode: 'cors',
      credentials: "same-origin"
    })
      .then(function(response) {
        return response.json();
      })
      .then((body) => {
        if(canceled) {
          return;
        }

        this.setState({
          activeRequest: null,
          activeRequestUrl: null
        });

        const mapStyle = style.ensureStyleValidity(body)
        console.log('Loaded style ', mapStyle.id)
        this.props.onStyleOpen(mapStyle)
        this.onOpenToggle()
      })
      .catch((err) => {
        this.setState({
          error: `Failed to load: '${styleUrl}'`,
          activeRequest: null,
          activeRequestUrl: null
        });
        console.error(err);
        console.warn('Could not open the style URL', styleUrl)
      })

    this.setState({
      activeRequest: {
        abort: function() {
          canceled = true;
        }
      },
      activeRequestUrl: styleUrl
    })
  }

  onSubmitUrl = (e: FormEvent<HTMLFormElement>) => {
    e.preventDefault();
    this.onStyleSelect(this.state.styleUrl);
  }

  onUpload = (_: any, files: Result[]) => {
    const [, file] = files[0];
    const reader = new FileReader();

    this.clearError();

    reader.readAsText(file, "UTF-8");
    reader.onload = e => {
      let mapStyle;
      try {
        mapStyle = JSON.parse(e.target?.result as string)
      }
      catch(err) {
        this.setState({
          error: (err as Error).toString()
        });
        return;
      }
      mapStyle = style.ensureStyleValidity(mapStyle)
      this.props.onStyleOpen(mapStyle);
      this.onOpenToggle();
    }
    reader.onerror = e => console.log(e.target);
  }

  onOpenToggle() {
    this.setState({
      styleUrl: ""
    });
    this.clearError();
    this.props.onOpenToggle();
  }

  onChangeUrl = (url: string) => {
    this.setState({
      styleUrl: url,
    });
  }

  render() {
    const styleOptions = publicStyles.map(style => {
      return <PublicStyle
        key={style.id}
        url={style.url}
        title={style.title}
        thumbnailUrl={style.thumbnail}
        onSelect={this.onStyleSelect}
      />
    })

    let errorElement;
    if(this.state.error) {
      errorElement = (
        <div className="maputnik-modal-error">
          {this.state.error}
          <a href="#" onClick={() => this.clearError()} className="maputnik-modal-error-close">×</a>
        </div>
      );
    }

    return  (
      <div>
        <Modal
          data-wd-key="modal:open"
          isOpen={this.props.isOpen}
          onOpenToggle={() => this.onOpenToggle()}
          title={'Open Style'}
        >
          {errorElement}
          <section className="maputnik-modal-section">
            <h1>Upload Style</h1>
            <p>Upload a JSON style from your computer.</p>
            <FileReaderInput onChange={this.onUpload} tabIndex={-1} aria-label="Style file">
              <InputButton className="maputnik-upload-button"><MdFileUpload /> Upload</InputButton>
            </FileReaderInput>
          </section>

          <section className="maputnik-modal-section">
            <form onSubmit={this.onSubmitUrl}>
              <h1>Load from URL</h1>
              <p>
                Load from a URL. Note that the URL must have <a href="https://enable-cors.org" target="_blank" rel="noopener noreferrer">CORS enabled</a>.
              </p>
              <InputUrl
                aria-label="Style URL"
                data-wd-key="modal:open.url.input"
                type="text"
                className="maputnik-input"
                default="Enter URL..."
                value={this.state.styleUrl}
                onInput={this.onChangeUrl}
                onChange={this.onChangeUrl}
              />
              <div>
                <InputButton
                  data-wd-key="modal:open.url.button"
                  type="submit"
                  className="maputnik-big-button"
                  disabled={this.state.styleUrl.length < 1}
                >Load from URL</InputButton>
              </div>
            </form>
          </section>

          <section className="maputnik-modal-section maputnik-modal-section--shrink">
            <h1>Gallery Styles</h1>
            <p>
              Open one of the publicly available styles to start from.
            </p>
            <div className="maputnik-style-gallery-container">
              {styleOptions}
            </div>
          </section>
        </Modal>

        <ModalLoading
          isOpen={!!this.state.activeRequest}
          title={'Loading style'}
          onCancel={(e: Event) => this.onCancelActiveRequest(e)}
          message={"Loading: "+this.state.activeRequestUrl}
        />
      </div>
    )
  }
}