import { remote } from 'electron';
import {
  React,
  ReactDOM,
  localized,
  PropTypes,
  Utils,
  Actions,
  DraftStore,
  AttachmentStore,
} from 'mailspring-exports';
import {
  DropZone,
  RetinaImg,
  ScrollRegion,
  TabGroupRegion,
  AttachmentItem,
  KeyCommandsRegion,
  ImageAttachmentItem,
  InjectedComponentSet,
  ComposerEditor,
  ComposerSupport,
} from 'mailspring-component-kit';
import { History } from 'slate';
import ComposerHeader from './composer-header';
import SendActionButton from './send-action-button';
import ActionBarPlugins from './action-bar-plugins';
import Fields from './fields';

const {
  hasBlockquote,
  hasNonTrailingBlockquote,
  hideQuotedTextByDefault,
  removeQuotedText,
} = ComposerSupport.BaseBlockPlugins;

// The ComposerView is a unique React component because it (currently) is a
// singleton. Normally, the React way to do things would be to re-render the
// Composer with new props.
export default class ComposerView extends React.Component {
  static displayName = 'ComposerView';

  static propTypes = {
    session: PropTypes.object.isRequired,
    draft: PropTypes.object.isRequired,
    className: PropTypes.string,
  };

  constructor(props) {
    super(props);

    this._els = {};
    this._mounted = false;

    this._keymapHandlers = {
      'composer:send-message': () => this._onPrimarySend(),
      'composer:delete-empty-draft': () => this.props.draft.pristine && this._onDestroyDraft(),
      'composer:show-and-focus-bcc': () => this._els.header.showAndFocusField(Fields.Bcc),
      'composer:show-and-focus-cc': () => this._els.header.showAndFocusField(Fields.Cc),
      'composer:focus-to': () => this._els.header.showAndFocusField(Fields.To),
      'composer:show-and-focus-from': () => {},
      'composer:select-attachment': () => this._onSelectAttachment(),
    };

    const draft = props.session.draft();
    this.state = {
      isDropping: false,
      quotedTextPresent: hasBlockquote(draft.bodyEditorState),
      quotedTextHidden: hideQuotedTextByDefault(draft),
    };
  }

  componentDidMount() {
    this._mounted = true;
    this.props.draft.files.forEach(file => {
      if (Utils.shouldDisplayAsImage(file)) {
        Actions.fetchFile(file);
      }
    });

    const isBrandNew = Date.now() - this.props.draft.date < 3 * 1000;
    if (isBrandNew) {
      ReactDOM.findDOMNode(this).scrollIntoView(false);
      window.requestAnimationFrame(() => {
        this.focus();
      });
    }
  }

  componentDidUpdate() {
    const { draft } = this.props;

    // If the user has added an inline blockquote, show all the quoted text
    // note: this is necessary because it's hidden with CSS that can't be
    // made more specific.
    if (this.state.quotedTextHidden && hasNonTrailingBlockquote(draft.bodyEditorState)) {
      this.setState({ quotedTextHidden: false });
    }
  }

  componentWillUnmount() {
    this._mounted = false;

    // In the future, we should clean up the draft session entirely, or give it
    // the same lifecycle as the composer view. For now, just make sure we free
    // up all the memory used for undo/redo.
    const { draft, session } = this.props;
    session.changes.add({ bodyEditorState: draft.bodyEditorState.set('history', new History()) });
  }

  focus() {
    if (!this._mounted) return;

    // If something within us already has focus, don't change it. Never, ever
    // want to pull the cursor out from under the user while typing
    const node = ReactDOM.findDOMNode(this._els.composerWrap);
    if (node.contains(document.activeElement)) {
      return;
    }

    if (this.props.draft.to.length === 0 || this.props.draft.subject.length === 0) {
      this._els.header.focus();
    } else {
      this._els[Fields.Body].focus();
    }
  }

  _renderContentScrollRegion() {
    if (AppEnv.isComposerWindow()) {
      return (
        <ScrollRegion
          className="compose-body-scroll"
          ref={el => {
            if (el) {
              this._els.scrollregion = el;
            }
          }}
        >
          {this._renderContent()}
        </ScrollRegion>
      );
    }
    return this._renderContent();
  }

  _renderContent() {
    return (
      <div className="composer-centered">
        <ComposerHeader
          ref={el => {
            if (el) {
              this._els.header = el;
            }
          }}
          draft={this.props.draft}
          session={this.props.session}
          initiallyFocused={this.props.draft.to.length === 0}
        />
        <div
          className="compose-body"
          ref={el => {
            if (el) {
              this._els.composeBody = el;
            }
          }}
          onMouseUp={this._onMouseUpComposerBody}
          onMouseDown={this._onMouseDownComposerBody}
        >
          {this._renderBodyRegions()}
          {this._renderFooterRegions()}
        </div>
      </div>
    );
  }

  _renderBodyRegions() {
    return (
      <div className="composer-body-wrap">
        {this._renderEditor()}
        {this._renderQuotedTextControl()}
        {this._renderAttachments()}
      </div>
    );
  }

  _renderQuotedTextControl() {
    if (!this.state.quotedTextPresent || !this.state.quotedTextHidden) {
      return false;
    }
    return (
      <a
        className="quoted-text-control"
        onMouseDown={e => {
          if (e.target.closest('.remove-quoted-text')) return;
          e.preventDefault();
          e.stopPropagation();
          this.setState({ quotedTextHidden: false });
        }}
      >
        <span className="dots">&bull;&bull;&bull;</span>
        <span
          className="remove-quoted-text"
          onMouseUp={e => {
            e.preventDefault();
            e.stopPropagation();
            const { draft, session } = this.props;
            const change = removeQuotedText(draft.bodyEditorState);
            session.changes.add({ bodyEditorState: change.value });
            this.setState({ quotedTextHidden: false });
          }}
        >
          <RetinaImg
            title={localized('Remove quoted text')}
            name="image-cancel-button.png"
            mode={RetinaImg.Mode.ContentPreserve}
          />
        </span>
      </a>
    );
  }

  _renderEditor() {
    return (
      <ComposerEditor
        ref={el => {
          if (el) {
            this._els[Fields.Body] = el;
          }
        }}
        className={this.state.quotedTextHidden && 'hiding-quoted-text'}
        propsForPlugins={{ draft: this.props.draft, session: this.props.session }}
        value={this.props.draft.bodyEditorState}
        onFileReceived={this._onFileReceived}
        onDrop={e => this._dropzone._onDrop(e)}
        onChange={change => {
          // We minimize thrashing and support editors in multiple windows by ensuring
          // non-value changes (eg focus) to the editorState don't trigger database saves
          const skipSaving = change.operations.every(
            ({ type, properties }) =>
              type === 'set_selection' ||
              (type === 'set_value' && Object.keys(properties).every(k => k === 'decorations'))
          );
          this.props.session.changes.add({ bodyEditorState: change.value }, { skipSaving });
        }}
      />
    );
  }

  _renderFooterRegions() {
    return (
      <div className="composer-footer-region">
        <InjectedComponentSet
          deferred
          matching={{ role: 'Composer:Footer' }}
          exposedProps={{
            draft: this.props.draft,
            threadId: this.props.draft.threadId,
            headerMessageId: this.props.draft.headerMessageId,
            session: this.props.session,
          }}
          direction="column"
        />
      </div>
    );
  }

  _renderAttachments() {
    const { files, headerMessageId } = this.props.draft;

    const nonImageFiles = files
      .filter(f => !Utils.shouldDisplayAsImage(f))
      .map(file => (
        <AttachmentItem
          key={file.id}
          className="file-upload"
          draggable={false}
          filePath={AttachmentStore.pathForFile(file)}
          displayName={file.filename}
          fileIconName={`file-${file.extension}.png`}
          onRemoveAttachment={() => Actions.removeAttachment(headerMessageId, file)}
        />
      ));
    const imageFiles = files
      .filter(f => Utils.shouldDisplayAsImage(f))
      .filter(f => !f.contentId)
      .map(file => (
        <ImageAttachmentItem
          key={file.id}
          draggable={false}
          className="file-upload"
          filePath={AttachmentStore.pathForFile(file)}
          displayName={file.filename}
          onRemoveAttachment={() => Actions.removeAttachment(headerMessageId, file)}
        />
      ));

    return <div className="attachments-area">{nonImageFiles.concat(imageFiles)}</div>;
  }

  _renderActionsWorkspaceRegion() {
    return (
      <InjectedComponentSet
        deferred
        matching={{ role: 'Composer:ActionBarWorkspace' }}
        exposedProps={{
          draft: this.props.draft,
          threadId: this.props.draft.threadId,
          headerMessageId: this.props.draft.headerMessageId,
          session: this.props.session,
        }}
      />
    );
  }

  _renderActionsRegion() {
    return (
      <div className="composer-action-bar-content">
        <ActionBarPlugins
          draft={this.props.draft}
          session={this.props.session}
          isValidDraft={this._isValidDraft}
        />

        <button
          tabIndex={-1}
          className="btn btn-toolbar btn-trash"
          style={{ order: 100 }}
          title={localized('Delete Draft')}
          onClick={this._onDestroyDraft}
        >
          <RetinaImg name="icon-composer-trash.png" mode={RetinaImg.Mode.ContentIsMask} />
        </button>

        <button
          tabIndex={-1}
          className="btn btn-toolbar btn-attach"
          style={{ order: 50 }}
          title={localized('Attach File')}
          onClick={this._onSelectAttachment}
        >
          <RetinaImg name="icon-composer-attachment.png" mode={RetinaImg.Mode.ContentIsMask} />
        </button>

        <div style={{ order: 0, flex: 1 }} />

        <SendActionButton
          ref={el => {
            if (el) {
              this._els.sendActionButton = el;
            }
          }}
          tabIndex={-1}
          style={{ order: -100 }}
          draft={this.props.draft}
          headerMessageId={this.props.draft.headerMessageId}
          session={this.props.session}
          isValidDraft={this._isValidDraft}
        />
      </div>
    );
  }

  // This lets us click outside of the `contenteditable`'s `contentBody`
  // and simulate what happens when you click beneath the text *in* the
  // contentEditable.

  // Unfortunately, we need to manually keep track of the "click" in
  // separate mouseDown, mouseUp events because we need to ensure that the
  // start and end target are both not in the contenteditable. This ensures
  // that this behavior doesn't interfear with a click and drag selection.
  _onMouseDownComposerBody = event => {
    if (ReactDOM.findDOMNode(this._els[Fields.Body]).contains(event.target)) {
      this._mouseDownTarget = null;
    } else {
      this._mouseDownTarget = event.target;
    }
  };

  _inFooterRegion(el) {
    return el.closest && el.closest('.composer-footer-region');
  }

  _onMouseUpComposerBody = event => {
    if (event.target === this._mouseDownTarget && !this._inFooterRegion(event.target)) {
      // We don't set state directly here because we want the native
      // contenteditable focus behavior. When the contenteditable gets focused
      const bodyRect = ReactDOM.findDOMNode(this._els[Fields.Body]).getBoundingClientRect();
      if (event.pageY < bodyRect.top) {
        this._els[Fields.Body].focus();
      } else {
        if (this.state.quotedTextHidden) {
          this._els[Fields.Body].focusEndReplyText();
        } else {
          this._els[Fields.Body].focusEndAbsolute();
        }
      }
    }
    this._mouseDownTarget = null;
  };

  _shouldAcceptDrop = event => {
    // Ensure that you can't pick up a file and drop it on the same draft
    const nonNativeFilePath = this._nonNativeFilePathForDrop(event);

    const hasNativeFile = event.dataTransfer.types.includes('Files');
    const hasNonNativeFilePath = nonNativeFilePath !== null;

    return hasNativeFile || hasNonNativeFilePath;
  };

  _nonNativeFilePathForDrop = event => {
    if (event.dataTransfer.types.includes('text/nylas-file-url')) {
      const downloadURL = event.dataTransfer.getData('text/nylas-file-url');
      const downloadFilePath = downloadURL.split('file://')[1];
      if (downloadFilePath) {
        return downloadFilePath;
      }
    }

    // Accept drops of images from within the app
    if (event.dataTransfer.types.includes('text/uri-list')) {
      const uri = event.dataTransfer.getData('text/uri-list');
      if (uri.indexOf('file://') === 0) {
        return decodeURI(uri.split('file://')[1]);
      }
    }
    return null;
  };

  _onDrop = event => {
    // Accept drops of real files from other applications
    for (const file of Array.from(event.dataTransfer.files)) {
      this._onFileReceived(file.path);
      event.preventDefault();
    }

    // Accept drops from attachment components / images within the app
    const uri = this._nonNativeFilePathForDrop(event);
    if (uri) {
      this._onFileReceived(uri);
      event.preventDefault();
    }
  };

  _onFileReceived = filePath => {
    // called from onDrop and onFilePaste - assume images should be inline
    Actions.addAttachment({
      filePath: filePath,
      headerMessageId: this.props.draft.headerMessageId,
      onCreated: file => {
        if (!this._mounted) return;
        if (Utils.shouldDisplayAsImage(file)) {
          const { draft, session } = this.props;
          const match = draft.files.find(f => f.id === file.id);
          if (!match) {
            return;
          }
          match.contentId = Utils.generateContentId();
          session.changes.add({
            files: [].concat(draft.files),
          });

          this._els[Fields.Body].insertInlineAttachment(file);
        }
      },
    });
  };

  _isValidDraft = (options = {}) => {
    // We need to check the `DraftStore` because the `DraftStore` is
    // immediately and synchronously updated as soon as this function
    // fires. Since `setState` is asynchronous, if we used that as our only
    // check, then we might get a false reading.
    if (DraftStore.isSendingDraft(this.props.draft.headerMessageId)) {
      return false;
    }

    const dialog = remote.dialog;
    const { session } = this.props;
    const { errors, warnings } = session.validateDraftForSending();

    if (errors.length > 0) {
      dialog.showMessageBox(remote.getCurrentWindow(), {
        type: 'warning',
        buttons: [localized('Edit Message'), localized('Cancel')],
        message: localized('Cannot send message'),
        detail: errors[0],
      });
      return false;
    }

    if (warnings.length > 0 && !options.force) {
      const response = dialog.showMessageBox(remote.getCurrentWindow(), {
        type: 'warning',
        buttons: [localized('Send Anyway'), localized('Cancel')],
        message: localized('Are you sure?'),
        detail: warnings.join('. '),
      });
      if (response === 0) {
        // response is button array index
        return this._isValidDraft({ force: true });
      }
      return false;
    }
    return true;
  };

  _onPrimarySend = () => {
    this._els.sendActionButton.primarySend();
  };

  _onDestroyDraft = () => {
    Actions.destroyDraft(this.props.draft);
  };

  _onSelectAttachment = () => {
    Actions.selectAttachment({ headerMessageId: this.props.draft.headerMessageId });
  };

  render() {
    const dropCoverDisplay = this.state.isDropping ? 'block' : 'none';

    return (
      <div className={this.props.className}>
        <KeyCommandsRegion
          localHandlers={this._keymapHandlers}
          className={'message-item-white-wrap composer-outer-wrap'}
          ref={el => {
            if (el) {
              this._els.composerWrap = el;
            }
          }}
          tabIndex="-1"
        >
          <TabGroupRegion className="composer-inner-wrap">
            <DropZone
              ref={cm => (this._dropzone = cm)}
              className="composer-inner-wrap"
              shouldAcceptDrop={this._shouldAcceptDrop}
              onDragStateChange={({ isDropping }) => this.setState({ isDropping })}
              onDrop={this._onDrop}
            >
              <div className="composer-drop-cover" style={{ display: dropCoverDisplay }}>
                <div className="centered">
                  <RetinaImg
                    name="composer-drop-to-attach.png"
                    mode={RetinaImg.Mode.ContentIsMask}
                  />
                  {localized(`Drop to Attach`)}
                </div>
              </div>

              <div className="composer-content-wrap">{this._renderContentScrollRegion()}</div>

              <div className="composer-action-bar-workspace-wrap">
                {this._renderActionsWorkspaceRegion()}
              </div>

              <div className="composer-action-bar-wrap" data-tooltips-anchor>
                <div className="tooltips-container" />
                {this._renderActionsRegion()}
              </div>
            </DropZone>
          </TabGroupRegion>
        </KeyCommandsRegion>
      </div>
    );
  }
}