import { effect, h } from '@ui-arch/frame';
import type { SwitchProps } from './types.js';

/*** 开关：checked 信号双向绑定，disabled 支持布尔或信号禁用，轨道 + 滑块的纯 CSS 实现 ***/
export function switchButton(props: SwitchProps): HTMLElement {
  const input = h('input', {
    type: 'checkbox',
    class: 'ua-switch-input',
    role: 'switch', // 用开关语义而非复选框：读屏播报「开关」并跟随选中态
    'aria-label': props.ariaLabel ?? props.label, // 无可见文案时也要有可访问名
    disabled: props.disabled, // false/undefined 移除属性，Signal 走响应式
  }) as HTMLInputElement;
  if (props.checked) {
    const checked = props.checked;
    input.addEventListener('change', () => checked(input.checked)); // 用户切换写回信号
    effect(() => {
      if (input.checked !== checked()) input.checked = checked(); // 外部变化写回开关
    });
  }
  if (props.onChange) input.addEventListener('change', () => props.onChange!(input.checked));
  const track = h('span', { class: 'ua-switch-track' }, h('span', { class: 'ua-switch-thumb' }));
  const el = h('label', { class: 'ua-switch' }, input, track);
  if (props.label) el.append(h('span', { class: 'ua-switch-label' }, props.label));
  return el;
}