// @flow
import React, { Component } from 'react';
import get from 'lodash/get';
import styled from 'styled-components';
import { observer } from 'mobx-react';
import { withRouter, Prompt } from 'react-router';
import { Flex } from 'reflexbox';

import DocumentStore from './DocumentStore';
import Breadcrumbs from './components/Breadcrumbs';
import Menu from './components/Menu';
import Editor from 'components/Editor';
import Layout, { HeaderAction, SaveAction } from 'components/Layout';
import PublishingInfo from 'components/PublishingInfo';
import AtlasPreviewLoading from 'components/AtlasPreviewLoading';
import CenteredContent from 'components/CenteredContent';

const DISCARD_CHANGES = `
You have unsaved changes.
Are you sure you want to discard them?
`;

const Container = styled.div`
  position: relative;
  font-weight: 400;
  font-size: 1em;
  line-height: 1.5em;
  padding: 0 3em;
  width: 50em;
`;

const Meta = styled.div`
  position: absolute;
  top: 12px;
`;

type Props = {
  match: Object,
  history: Object,
  keydown: Object,
  newChildDocument?: boolean,
};

@observer class Document extends Component {
  store: DocumentStore;
  props: Props;

  constructor(props: Props) {
    super(props);
    this.store = new DocumentStore({ history: this.props.history });
  }

  componentDidMount = () => {
    if (this.props.newDocument) {
      this.store.collectionId = this.props.match.params.id;
      this.store.newDocument = true;
    } else if (this.props.match.params.edit) {
      this.store.documentId = this.props.match.params.id;
      this.store.fetchDocument();
    } else if (this.props.newChildDocument) {
      this.store.documentId = this.props.match.params.id;
      this.store.newChildDocument = true;
      this.store.fetchDocument();
    } else {
      this.store.documentId = this.props.match.params.id;
      this.store.newDocument = false;
      this.store.fetchDocument();
    }
  };

  onEdit = () => {
    const url = `${this.store.document.url}/edit`;
    this.props.history.push(url);
  };

  onSave = (options: { redirect?: boolean } = {}) => {
    if (this.store.newDocument || this.store.newChildDocument) {
      this.store.saveDocument(options);
    } else {
      this.store.updateDocument(options);
    }
  };

  onImageUploadStart = () => {
    this.store.updateUploading(true);
  };

  onImageUploadStop = () => {
    this.store.updateUploading(false);
  };

  onCancel = () => {
    this.props.history.goBack();
  };

  render() {
    const isNew = this.props.newDocument || this.props.newChildDocument;
    const isEditing = this.props.match.params.edit;
    const title = (
      <Breadcrumbs
        document={this.store.document}
        pathToDocument={this.store.pathToDocument}
      />
    );

    const titleText =
      this.store.document &&
      `${get(this.store, 'document.collection.name')} - ${get(this.store, 'document.title')}`;

    const actions = (
      <Flex>
        <HeaderAction>
          {isEditing
            ? <SaveAction
                onClick={this.onSave}
                disabled={this.store.isSaving}
                isNew={!!isNew}
              />
            : <a onClick={this.onEdit}>Edit</a>}
        </HeaderAction>
        <Menu
          store={this.store}
          document={this.store.document}
          collectionTree={this.store.collectionTree}
        />
      </Flex>
    );

    return (
      <Layout
        actions={actions}
        title={title}
        titleText={titleText}
        loading={this.store.isSaving || this.store.isUploading}
        search={false}
        fixed
      >
        <Prompt when={this.store.hasPendingChanges} message={DISCARD_CHANGES} />
        {this.store.isFetching &&
          <CenteredContent>
            <AtlasPreviewLoading />
          </CenteredContent>}
        {this.store.document &&
          <Container>
            {!isEditing &&
              <Meta>
                <PublishingInfo
                  collaborators={this.store.document.collaborators}
                  createdAt={this.store.document.createdAt}
                  createdBy={this.store.document.createdBy}
                  updatedAt={this.store.document.updatedAt}
                  updatedBy={this.store.document.updatedBy}
                />
              </Meta>}
            <Editor
              text={this.store.document.text}
              onImageUploadStart={this.onImageUploadStart}
              onImageUploadStop={this.onImageUploadStop}
              onChange={this.store.updateText}
              onSave={this.onSave}
              onCancel={this.onCancel}
              readOnly={!isEditing}
            />
          </Container>}
      </Layout>
    );
  }
}

export default withRouter(Document);