Add bot-driven room app UI via im.paarrot.ui state.

Bots can publish a declarative panel UI that takes over a room; user
actions are sent as im.paarrot.ui.action timeline events.

src/app/features/room-app/RoomAppSchema.tsx

@@ -0,0 +1,205 @@
+import React, { useCallback, useMemo, useState } from 'react';
+import { Box, Button, Input, Text, config } from 'folds';
+import { MatrixClient } from 'matrix-js-sdk';
+import {
+  PaarrotUiActionContent,
+  PaarrotUiButtonNode,
+  PaarrotUiContent,
+  PaarrotUiNode,
+} from '../../../types/matrix/room';
+import { mxcUrlToHttp } from '../../utils/matrix';
+import { isAllowedRoomAppImageSrc, scopeRoomAppCss } from './sanitizeRoomAppCss';
+import * as css from './RoomAppView.css';
+
+const SCOPE = '[data-room-app]';
+
+type RoomAppSchemaProps = {
+  mx: MatrixClient;
+  content: PaarrotUiContent;
+  uiEventId?: string;
+  useAuthentication: boolean;
+  onAction: (payload: PaarrotUiActionContent) => void | Promise<void>;
+};
+
+function fieldName(node: { id: string; name?: string }): string {
+  return node.name || node.id;
+}
+
+function spacerSize(size?: number): 'sm' | 'md' | 'lg' {
+  if (typeof size === 'number' && size <= 8) return 'sm';
+  if (typeof size === 'number' && size >= 24) return 'lg';
+  return 'md';
+}
+
+export function RoomAppSchema({
+  mx,
+  content,
+  uiEventId,
+  useAuthentication,
+  onAction,
+}: RoomAppSchemaProps) {
+  const [values, setValues] = useState<Record<string, string>>({});
+  const [sending, setSending] = useState(false);
+
+  const scopedCss = useMemo(
+    () => (content.css ? scopeRoomAppCss(content.css, SCOPE) : ''),
+    [content.css]
+  );
+
+  const setField = useCallback((name: string, value: string) => {
+    setValues((prev) => ({ ...prev, [name]: value }));
+  }, []);
+
+  const handleButton = useCallback(
+    async (node: PaarrotUiButtonNode) => {
+      if (node.disabled || sending) return;
+      setSending(true);
+      try {
+        await onAction({
+          action: node.action,
+          component_id: node.id,
+          value: node.value,
+          values: { ...values },
+          ui_event_id: uiEventId,
+        });
+      } finally {
+        setSending(false);
+      }
+    },
+    [onAction, sending, uiEventId, values]
+  );
+
+  const renderNode = (node: PaarrotUiNode): React.ReactNode => {
+    switch (node.type) {
+      case 'panel':
+        return (
+          <div key={node.id} className={css.Panel} data-room-app-node={node.id}>
+            {node.children?.map((child) => renderNode(child))}
+          </div>
+        );
+      case 'row':
+        return (
+          <div key={node.id} className={css.Row} data-room-app-node={node.id}>
+            {node.children?.map((child) => renderNode(child))}
+          </div>
+        );
+      case 'text':
+        return (
+          <Text
+            key={node.id}
+            as="p"
+            size="T400"
+            className={node.className}
+            data-room-app-node={node.id}
+          >
+            {node.text ?? ''}
+          </Text>
+        );
+      case 'button': {
+        const variant = node.variant ?? 'Primary';
+        return (
+          <Button
+            key={node.id}
+            type="button"
+            size="400"
+            variant={variant}
+            radii="300"
+            disabled={node.disabled || sending}
+            onClick={() => handleButton(node)}
+            data-room-app-node={node.id}
+          >
+            <Text size="B400">{node.label}</Text>
+          </Button>
+        );
+      }
+      case 'input': {
+        const name = fieldName(node);
+        const current = values[name] ?? node.value ?? '';
+        return (
+          <div key={node.id} className={css.Field} data-room-app-node={node.id}>
+            {node.label && (
+              <Text as="label" size="L400" htmlFor={`room-app-${node.id}`}>
+                {node.label}
+              </Text>
+            )}
+            <Input
+              id={`room-app-${node.id}`}
+              name={name}
+              variant="Background"
+              radii="300"
+              type={node.inputType ?? 'text'}
+              placeholder={node.placeholder}
+              value={current}
+              onChange={(evt) => setField(name, evt.currentTarget.value)}
+            />
+          </div>
+        );
+      }
+      case 'select': {
+        const name = fieldName(node);
+        const current = values[name] ?? node.value ?? '';
+        return (
+          <div key={node.id} className={css.Field} data-room-app-node={node.id}>
+            {node.label && (
+              <Text as="label" size="L400" htmlFor={`room-app-${node.id}`}>
+                {node.label}
+              </Text>
+            )}
+            <Box as="span" grow="Yes" style={{ position: 'relative' }}>
+              <select
+                id={`room-app-${node.id}`}
+                name={name}
+                value={current}
+                onChange={(evt) => setField(name, evt.currentTarget.value)}
+                style={{
+                  width: '100%',
+                  padding: `${config.space.S200} ${config.space.S300}`,
+                  borderRadius: config.radii.R300,
+                  border: '1px solid var(--bq-border, CurrentColor)',
+                  background: 'transparent',
+                  color: 'inherit',
+                  font: 'inherit',
+                }}
+              >
+                {(node.options ?? []).map((opt) => (
+                  <option key={opt.value} value={opt.value}>
+                    {opt.label}
+                  </option>
+                ))}
+              </select>
+            </Box>
+          </div>
+        );
+      }
+      case 'image': {
+        if (!isAllowedRoomAppImageSrc(node.src)) return null;
+        const httpSrc = node.src.startsWith('mxc://')
+          ? mxcUrlToHttp(mx, node.src, useAuthentication) ?? undefined
+          : node.src;
+        if (!httpSrc) return null;
+        return (
+          <img
+            key={node.id}
+            className={css.Image}
+            src={httpSrc}
+            alt={node.alt ?? ''}
+            width={node.width}
+            height={node.height}
+            data-room-app-node={node.id}
+          />
+        );
+      }
+      case 'spacer':
+        return <div key={node.id} className={css.Spacer({ size: spacerSize(node.size) })} />;
+      default:
+        return null;
+    }
+  };
+
+  return (
+    <div data-room-app="">
+      {scopedCss ? <style>{scopedCss}</style> : null}
+      {renderNode(content.root)}
+    </div>
+  );
+}