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

/*** 进度条：value 信号驱动 0-100 定量态（缺省则不确定态），type='circle' 且传 value 时出环形；满格切 success 色 ***/
export function progress(props: ProgressProps = {}): HTMLElement {
  // —— 状态集中声明 ——
  const value = props.value;                 // 可选：不传即不确定态
  const fill = h('div', { class: 'ua-progress-fill' });
  const track = h('div', { class: 'ua-progress-track' }, fill);
  const text = h('span', { class: 'ua-progress-text' });
  const withText = props.showText !== false && !!value; // 不确定态没有百分比可显示
  const label = props.label;                 // 可访问名：读屏念「上传进度 50%」而不是干巴巴的百分比
  const variant = props.variant ?? 'default'; // 语义色：default 之外都带类名，满格时仍以 variant 为准
  const cls = `ua-progress${variant === 'default' ? '' : ` ua-progress-${variant}`}`;

  if (!value) {
    fill.classList.add('ua-indeterminate');  // 宽度与往复动画交给 CSS
    return h('div', { class: cls, role: 'progressbar', 'aria-label': label ?? '进行中' }, track);
  }
  if (props.type === 'circle') return ring(value, label, variant, withText); // 环形：SVG 版
  effect(() => {
    const v = clamp(value()); // 依赖收集：信号变化自动写回
    fill.style.width = `${v}%`;
    fill.classList.toggle('ua-done', v >= 100); // 满格切语义色
    text.textContent = `${Math.round(v)}%`;
  });
  return h(
    'div',
    {
      class: cls,
      role: 'progressbar',
      'aria-label': label,
      'aria-valuemin': '0',
      'aria-valuemax': '100',
      'aria-valuenow': () => String(Math.round(clamp(value()))),
    },
    track,
    withText ? text : null,
  );
}

/*** 进度钳制到 0-100 ***/
function clamp(v: number): number {
  if (Number.isNaN(v)) return 0; // 卫语句：非法值归零
  return Math.min(100, Math.max(0, v));
}

/*** 环形进度：SVG 双圆用 dashoffset 表达弧长（必须 createElementNS，h() 造不出可渲染的 SVG） ***/
function ring(value: Signal<number>, label: string | undefined, variant: string, withText: boolean): HTMLElement {
  const NS = 'http://www.w3.org/2000/svg'; // SVG 命名空间
  const R = 26;            // 半径：viewBox 64 两侧留出线宽
  const C = 2 * Math.PI * R; // 周长：dasharray 的基准长度
  const svg = document.createElementNS(NS, 'svg');
  svg.setAttribute('viewBox', '0 0 64 64');
  svg.setAttribute('class', `ua-progress-ring${variant === 'default' ? '' : ` is-${variant}`}`);
  svg.setAttribute('role', 'img');
  const base = { cx: '32', cy: '32', r: String(R), fill: 'none', 'stroke-width': '6' }; // 两圆共用几何
  const track = document.createElementNS(NS, 'circle');
  const arc = document.createElementNS(NS, 'circle');
  for (const [k, v] of Object.entries({ ...base, class: 'ua-progress-ring-track' })) track.setAttribute(k, v);
  for (const [k, v] of Object.entries({ ...base, class: 'ua-progress-ring-arc', 'stroke-dasharray': String(C), transform: 'rotate(-90 32 32)' })) arc.setAttribute(k, v); // 从 12 点起画
  svg.append(track, arc);
  const txt = document.createElementNS(NS, 'text');
  txt.setAttribute('x', '32');
  txt.setAttribute('y', '36');
  txt.setAttribute('text-anchor', 'middle');
  txt.setAttribute('class', 'ua-progress-ring-text');
  if (withText) svg.append(txt);
  effect(() => {
    const v = clamp(value());
    arc.setAttribute('stroke-dashoffset', String(C * (1 - v / 100))); // 弧长按比例收缩
    txt.textContent = `${Math.round(v)}%`;
    svg.setAttribute('aria-label', `${label ?? '进度'} ${Math.round(v)}%`); // 环形没有原生 progressbar，名称自己拼
  });
  return h('div', { class: 'ua-progress ua-progress-circle' }, svg as unknown as HTMLElement) as HTMLElement;
}