Show media modal on public pages (#6801)

app/javascript/mastodon/components/media_gallery.js

@@ -14,10 +14,6 @@ const messages = defineMessages({
 
 class Item extends React.PureComponent {
 
-  static contextTypes = {
-    router: PropTypes.object,
-  };
-
   static propTypes = {
     attachment: ImmutablePropTypes.map.isRequired,
     standalone: PropTypes.bool,
@@ -53,7 +49,7 @@ class Item extends React.PureComponent {
   handleClick = (e) => {
     const { index, onClick } = this.props;
 
-    if (this.context.router && e.button === 0) {
+    if (e.button === 0) {
       e.preventDefault();
       onClick(index);
     }

app/javascript/mastodon/components/modal_root.js

@@ -0,0 +1,84 @@
+import React from 'react';
+import PropTypes from 'prop-types';
+
+export default class ModalRoot extends React.PureComponent {
+
+  static propTypes = {
+    children: PropTypes.node,
+    onClose: PropTypes.func.isRequired,
+  };
+
+  state = {
+    revealed: !!this.props.children,
+  };
+
+  activeElement = this.state.revealed ? document.activeElement : null;
+
+  handleKeyUp = (e) => {
+    if ((e.key === 'Escape' || e.key === 'Esc' || e.keyCode === 27)
+         && !!this.props.children) {
+      this.props.onClose();
+    }
+  }
+
+  componentDidMount () {
+    window.addEventListener('keyup', this.handleKeyUp, false);
+  }
+
+  componentWillReceiveProps (nextProps) {
+    if (!!nextProps.children && !this.props.children) {
+      this.activeElement = document.activeElement;
+
+      this.getSiblings().forEach(sibling => sibling.setAttribute('inert', true));
+    } else if (!nextProps.children) {
+      this.setState({ revealed: false });
+    }
+  }
+
+  componentDidUpdate (prevProps) {
+    if (!this.props.children && !!prevProps.children) {
+      this.getSiblings().forEach(sibling => sibling.removeAttribute('inert'));
+      this.activeElement.focus();
+      this.activeElement = null;
+    }
+    if (this.props.children) {
+      requestAnimationFrame(() => {
+        this.setState({ revealed: true });
+      });
+    }
+  }
+
+  componentWillUnmount () {
+    window.removeEventListener('keyup', this.handleKeyUp);
+  }
+
+  getSiblings = () => {
+    return Array(...this.node.parentElement.childNodes).filter(node => node !== this.node);
+  }
+
+  setRef = ref => {
+    this.node = ref;
+  }
+
+  render () {
+    const { children, onClose } = this.props;
+    const { revealed } = this.state;
+    const visible = !!children;
+
+    if (!visible) {
+      return (
+        <div className='modal-root' ref={this.setRef} style={{ opacity: 0 }} />
+      );
+    }
+
+    return (
+      <div className='modal-root' ref={this.setRef} style={{ opacity: revealed ? 1 : 0 }}>
+        <div style={{ pointerEvents: visible ? 'auto' : 'none' }}>
+          <div role='presentation' className='modal-root__overlay' onClick={onClose} />
+          <div role='dialog' className='modal-root__container'>{children}</div>
+        </div>
+      </div>
+    );
+  }
+
+}