feat(ui): add surface layout primitives

packages/ui/src/components/Surface.tsx

@@ -0,0 +1,100 @@
+import * as React from 'react';
+import { clsx } from 'clsx';
+
+export interface SurfaceProps extends React.HTMLAttributes<HTMLElement> {
+  as?: 'section' | 'aside' | 'article' | 'div';
+  variant?: 'default' | 'muted' | 'elevated' | 'outline' | 'plain';
+  padding?: 'none' | 'sm' | 'md' | 'lg';
+}
+
+const surfaceVariants: Record<NonNullable<SurfaceProps['variant']>, string> = {
+  default: 'border border-[var(--bl-border)] bg-[var(--bl-surface-card)]',
+  muted: 'border border-[var(--bl-border)] bg-[var(--bl-surface-muted)]',
+  elevated: 'border border-[var(--bl-border)] bg-[var(--bl-bg-elevated)] shadow-sm',
+  outline: 'border border-[var(--bl-border)] bg-transparent',
+  plain: 'border-transparent bg-transparent',
+};
+
+const surfacePadding: Record<NonNullable<SurfaceProps['padding']>, string> = {
+  none: '',
+  sm: 'p-3',
+  md: 'p-4',
+  lg: 'p-6',
+};
+
+export function Surface({
+  as: Comp = 'section',
+  variant = 'default',
+  padding = 'md',
+  className,
+  children,
+  ...props
+}: SurfaceProps) {
+  return (
+    <Comp
+      className={clsx(
+        'rounded-lg text-[var(--bl-text-primary)]',
+        surfaceVariants[variant],
+        surfacePadding[padding],
+        className
+      )}
+      {...props}
+    >
+      {children}
+    </Comp>
+  );
+}
+
+export interface SurfaceListProps extends React.HTMLAttributes<HTMLDivElement> {
+  density?: 'compact' | 'normal' | 'spacious';
+  divided?: boolean;
+}
+
+const listDensity: Record<NonNullable<SurfaceListProps['density']>, string> = {
+  compact: 'gap-1',
+  normal: 'gap-2',
+  spacious: 'gap-3',
+};
+
+export function SurfaceList({
+  density = 'normal',
+  divided,
+  className,
+  children,
+  ...props
+}: SurfaceListProps) {
+  return (
+    <div
+      className={clsx(
+        'grid',
+        listDensity[density],
+        divided &&
+          'divide-y divide-[var(--bl-border)] overflow-hidden rounded-lg border border-[var(--bl-border)]',
+        className
+      )}
+      {...props}
+    >
+      {children}
+    </div>
+  );
+}
+
+export interface SurfaceListItemProps extends React.HTMLAttributes<HTMLDivElement> {
+  selected?: boolean;
+}
+
+export function SurfaceListItem({ selected, className, children, ...props }: SurfaceListItemProps) {
+  return (
+    <div
+      data-selected={selected ? 'true' : undefined}
+      className={clsx(
+        'rounded-md border border-[var(--bl-border)] bg-[var(--bl-surface-muted)] p-3 text-[var(--bl-text-primary)]',
+        selected && 'border-[var(--bl-accent)] bg-[var(--bl-accent-muted,var(--bl-surface-card))]',
+        className
+      )}
+      {...props}
+    >
+      {children}
+    </div>
+  );
+}

packages/ui/src/index.ts

@@ -33,6 +33,14 @@ export {
   type PanelProps,
   type PanelTitleProps,
 } from './components/Panel';
+export {
+  Surface,
+  SurfaceList,
+  SurfaceListItem,
+  type SurfaceListItemProps,
+  type SurfaceListProps,
+  type SurfaceProps,
+} from './components/Surface';
 export { ListItemButton, type ListItemButtonProps } from './components/ListItemButton';
 export { Timeline, type TimelineItem, type TimelineProps } from './components/Timeline';
 export { DiffCard, type DiffCardProps } from './components/DiffCard';