export const metadata = { title: "@json-render/react API" }

# @json-render/react

React components, providers, and hooks.

## Providers

### StateProvider

```tsx
<StateProvider initialState={object}>
  {children}
</StateProvider>
```

### ActionProvider

```tsx
<ActionProvider handlers={Record<string, ActionHandler>}>
  {children}
</ActionProvider>

type ActionHandler = (params: Record<string, unknown>) => void | Promise<void>;
```

### VisibilityProvider

```tsx
<VisibilityProvider auth={AuthState}>
  {children}
</VisibilityProvider>

interface AuthState {
  isSignedIn: boolean;
  roles?: string[];
}
```

### ValidationProvider

```tsx
<ValidationProvider functions={Record<string, ValidatorFn>}>
  {children}
</ValidationProvider>

type ValidatorFn = (value: unknown, args?: object) => boolean | Promise<boolean>;
```

## defineRegistry

Create a type-safe component registry from a catalog. Components receive `props`, `children`, `emit`, and `loading` with catalog-inferred types.

```tsx
import { defineRegistry } from '@json-render/react';

const { registry } = defineRegistry(catalog, {
  components: {
    Card: ({ props, children }) => <div>{props.title}{children}</div>,
    Button: ({ props, emit }) => (
      <button onClick={() => emit?.("press")}>
        {props.label}
      </button>
    ),
  },
});

// Pass to <Renderer>
<Renderer spec={spec} registry={registry} />
```

## Components

### Renderer

```tsx
<Renderer
  spec={Spec}           // The UI spec to render
  registry={Registry}   // Component registry (from defineRegistry)
  loading={boolean}     // Optional loading state
  fallback={Component}  // Optional fallback for unknown types
/>

type Registry = Record<string, React.ComponentType<ComponentRenderProps>>;
```

### Component Props (via defineRegistry)

```tsx
interface ComponentContext<P> {
  props: P;                    // Typed props from catalog
  children?: React.ReactNode;  // Rendered children (for slot components)
  emit?: (event: string) => void;  // Emit a named event
  loading?: boolean;
}
```

## Hooks

### useUIStream

```typescript
const {
  spec,         // Spec | null - current UI state
  isStreaming,  // boolean - true while streaming
  error,        // Error | null
  send,         // (prompt: string, context?: Record<string, unknown>) => Promise<void>
  clear,        // () => void - reset spec and error
} = useUIStream({
  api: string,                         // API endpoint URL
  onComplete?: (spec: Spec) => void,   // Called when streaming completes
  onError?: (error: Error) => void,    // Called when an error occurs
});
```

### useStateStore

```typescript
const {
  data,      // Record<string, unknown>
  setState,   // (data: object) => void
  getValue,  // (path: string) => unknown
  setValue,  // (path: string, value: unknown) => void
} = useStateStore();
```

### useStateValue

```typescript
const value = useStateValue(path: string);
```

### useStateBinding

```typescript
const [value, setValue] = useStateBinding(path: string);
```

### useActions

```typescript
const { dispatch } = useActions();
// dispatch(actionName: string, params: object)
```

### useAction

```typescript
const submitForm = useAction('submit_form');
// submitForm(params: object)
```

### useIsVisible

```typescript
const isVisible = useIsVisible(condition?: VisibilityCondition);
```

### useFieldValidation

```typescript
const {
  value,     // unknown
  setValue,  // (value: unknown) => void
  errors,    // string[]
  validate,  // () => Promise<boolean>
  isValid,   // boolean
} = useFieldValidation(path: string, checks: ValidationCheck[]);
```