import { Story, Meta, html } from '@open-wc/demoing-storybook';
import { loadDefaultFeedbackMessages, Required, Validator } from '@lion/validate';

import '../lion-radio-group.js';
import '../lion-radio.js';

<Meta title="Forms/Radio Group" parameters={{ component: 'lion-radio-group' }} />

# Radio Group

You should use `<lion-radio>`s inside this element.

<Story name="Default">
  {html`
    <lion-radio-group name="dinos" label="What are your favourite dinosaurs?">
      <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
      <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'}></lion-radio>
      <lion-radio label="diplodocus" .choiceValue=${'diplodocus'}></lion-radio>
    </lion-radio-group>
  `}
</Story>

```html
<lion-radio-group name="dinos" label="What are your favourite dinosaurs?">
  <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
  <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'}></lion-radio>
  <lion-radio label="diplodocus" .choiceValue=${'diplodocus'}></lion-radio>
</lion-radio-group>
```

- Make sure that to use a name attribute as it is necessary for the [lion-form](?path=/docs/forms-form-overview--page)'s serialization result.
- If you have many options for a user to pick from, consider using [lion-select](?path=/docs/forms-select--default-story) instead

## Features

Since it extends from [lion-fieldset](?path=/docs/forms-fieldset-overview--page), it has all the features a fieldset has.

- Get or set the checked value of the group:
  - modelValue (default) - `checkedValue()`
  - formattedValue - `formattedValue()`
  - serializedValue - `serializedValue()`

## How to use

### Installation

```sh
npm i --save @lion/radio-group
```

```js
import '@lion/radio-group/lion-radio-group.js';
import '@lion/radio-group/lion-radio.js';
```


### Model value

The `modelValue` of a `lion-radio-group` is string equal to the `choiceValue` of the `lion-radio` element that has been checked.

Given the dinosaur example above, say that we were to select the last option (diplodocus).

Then the `modelValue` of the `lion-radio-group` will look as follows:

```js
const groupElement = [parent].querySelector('lion-radio-group');
groupElement.modelValue;
  => "diplodocus";
```

### The `name` attribute

The `name` attribute of a `lion-radio-group` automatically gets assigned to its `lion-radio` children. You can also specify names for the `lion-radio` elements, but if this name is different from the name assigned to `lion-radio-group`, then an exception will be thrown.

Our recommendation would be to set the `name` attribute only on the `lion-radio-group` and not on the `lion-checkbox` elements.

## Examples

### Pre-select

You can pre-select an option by adding the checked attribute to the selected `lion-radio`.

<Story name="Pre-select">
  {html`
    <lion-radio-group name="dinos" label="What are your favourite dinosaurs?">
      <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
      <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'} checked></lion-radio>
      <lion-radio label="diplodocus" .choiceValue=${'diplodocus'}></lion-radio>
    </lion-radio-group>
  `}
</Story>

```html
<lion-radio-group name="dinos" label="What are your favourite dinosaurs?">
  <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
  <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'} checked></lion-radio>
  <lion-radio label="diplodocus" .choiceValue=${'diplodocus'}></lion-radio>
</lion-radio-group>
```

### Disabled

You can disable a specific `lion-radio` option by adding the `disabled` attribute.

<Story name="Disabled radio">
  {html`
    <lion-radio-group name="dinos" label="What are your favourite dinosaurs?">
      <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
      <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'} disabled></lion-radio>
      <lion-radio label="diplodocus" .choiceValue=${'diplodocus'}></lion-radio>
    </lion-radio-group>
  `}
</Story>

```html
<lion-radio-group name="dinos" label="What are your favourite dinosaurs?">
  <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
  <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'} disabled></lion-radio>
  <lion-radio label="diplodocus" .choiceValue=${'diplodocus'}></lion-radio>
</lion-radio-group>
```

You can do the same thing for the entire group by setting the `disabled` attribute on the `lion-radio-group` element.

<Story name="Disabled group">
  {html`
    <lion-radio-group name="dinos" label="What are your favourite dinosaurs?" disabled>
      <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
      <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'}></lion-radio>
      <lion-radio label="diplodocus" .choiceValue=${'diplodocus'}></lion-radio>
    </lion-radio-group>
  `}
</Story>

```html
<lion-radio-group name="dinos" label="What are your favourite dinosaurs?">
  <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
  <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'} disabled></lion-radio>
  <lion-radio label="diplodocus" .choiceValue=${'diplodocus'}></lion-radio>
</lion-radio-group>
```

### Validation

<Story name="Validation">
  {() => {
    loadDefaultFeedbackMessages();
    const validate = () => {
      const radioGroup = document.querySelector('#dinos');
      radioGroup.submitted = !radioGroup.submitted;
    };
    return html`
      <lion-radio-group
        id="dinos"
        name="dinos"
        label="Favourite dinosaur"
        .validators=${[new Required()]}
      >
        <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
        <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'}></lion-radio>
        <lion-radio label="diplodocus" .choiceValue="${'diplodocus'}"></lion-radio>
      </lion-radio-group>
      <button @click="${() => validate()}">Validate</button>
    `;
  }}
</Story>

```js
import { loadDefaultFeedbackMessages, Required } from '@lion/validate';
loadDefaultFeedbackMessages();
const validate = () => {
  const radioGroup = document.querySelector('#dinosGroup');
  radioGroup.submitted = !radioGroup.submitted;
};
```

```html
<lion-radio-group
  id="dinos"
  name="dinos"
  label="Favourite dinosaur"
  .validators=${[new Required()]}
>
  <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
  <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'}></lion-radio>
  <lion-radio label="diplodocus" .choiceValue="${'diplodocus'}"></lion-radio>
</lion-radio-group>
<button @click="${() => validate()}">Validate</button>
```

You can also create a validator that validates whether a certain option is checked.

<Story name="Validate item">
  {() => {
    class IsBrontosaurus extends Validator {
      static get validatorName() {
        return 'IsBrontosaurus';
      }
      execute(value) {
        return value === 'brontosaurus';
      }
      static async getMessage() {
        return 'You need to select "brontosaurus"';
      }
    }
    const validate = () => {
      const radioGroup = document.querySelector('#dinosTwo');
      radioGroup.submitted = !radioGroup.submitted;
    };
    return html`
      <lion-radio-group
        id="dinosTwo"
        name="dinos"
        label="Favourite dinosaur"
        .validators=${[new Required(), new IsBrontosaurus()]}
      >
        <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
        <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'}></lion-radio>
        <lion-radio label="diplodocus" .choiceValue=${'diplodocus'}></lion-radio>
      </lion-radio-group>
      <button @click="${() => validate()}">Validate</button>
    `;
  }}
</Story>

```js
import { loadDefaultFeedbackMessages, Required, Validator } from '@lion/validate';

class IsBrontosaurus extends Validator {
  static get validatorName() {
    return 'IsBrontosaurus';
  }
  execute(value) {
    return value === 'brontosaurus';
  }
  static async getMessage() {
    return 'You need to select "brontosaurus"';
  }
}
const validate = () => {
  const radioGroup = document.querySelector('#dinosGroupTwo');
  radioGroup.submitted = !radioGroup.submitted;
};
```

```html
<lion-radio-group
  id="dinosGroupTwo"
  name="dinos"
  label="Favourite dinosaur"
  .validators=${[new Required(), new IsBrontosaurus()]}
>
  <lion-radio label="allosaurus" .choiceValue=${'allosaurus'}></lion-radio>
  <lion-radio label="brontosaurus" .choiceValue=${'brontosaurus'}></lion-radio>
  <lion-radio label="diplodocus" .choiceValue=${'diplodocus'}></lion-radio>
</lion-radio-group>
<button @click="${() => validate()}">Validate</button>
```
