import {
  createTable,
  filterPlugin,
  paginationPlugin,
  selectionPlugin,
  sortPlugin,
  type RowKey,
} from '@ui-arch/table-core';
import { iconSearch } from './icons.js'; import { computed, effect, h, renderList, signal } from '@ui-arch/frame';
import { attachResize } from './columnResize.js';
import { exportButton } from './csv.js';
import { skeleton } from './skeleton.js';
import { textField } from './textField.js';
import { emptyRow } from './tableEmpty.js';
import { tablePager } from './tablePager.js';
import { attachDataSource, readRows } from './tableDataSource.js';
import { bridgePage, bridgeSelection } from './tableBridge.js';
import { columnPicker } from './tableColumns.js';
import type { DataTableProps, TableApi } from './types.js';

/*** 数据表格：粘性表头 + 行选择 + 排序 + 筛选 + 分页 + 空状态；状态由 table-core 持有，信号只做桥接渲染 ***/
export function dataTable<T extends { id: RowKey }>(props: DataTableProps<T>): HTMLElement {
  const selectable = props.selectable ?? false; // 状态集中声明：行选择开关
  const keyword = signal(''); // 筛选框关键字：受控信号，空状态里的「清除筛选」靠它一键还原
  const table = createTable({
    data: readRows(props.data), // 信号数据源先取当前值，后续靠 attachDataSource 换
    columns: props.columns,
    rowKey: 'id',
    plugins: [filterPlugin<T>(), sortPlugin<T>(), paginationPlugin<T>(), selectionPlugin<T>()],
    initialState: { pagination: { page: 1, pageSize: props.pageSize ?? 5 } },
  });
  const api = table as unknown as TableApi<T>; // 用到的两个取数方法在类型别名里声明
  const version = signal(0); // 桥接信号：table-core 订阅通知 → 递增 → 派生统一重算
  table.subscribe(() => version(version() + 1)); attachDataSource(table, props.data); // 信号数据源变化即换源（静态数组直接返回）

  // —— 派生：全部由 version 单一来源推导，语义与内核一致 ——
  const visible = computed(() => {
    version();
    return table.getVisibleRows();
  });
  const state = computed(() => {
    version();
    return table.getState();
  });
  const info = computed(() => {
    visible();
    return api.getPageInfo();
  });
  const selectedCount = computed(() => state().selection.length);
  // 加载态读取器：布尔直接读，信号则保持响应性（供 renderList 依赖收集）
  const busy = (): boolean => (typeof props.loading === 'function' ? props.loading() : props.loading === true);
  // —— 受控桥接：页码与选中都走 tableBridge，外部信号与内核状态双向收敛 ——
  if (props.page) bridgePage({ page: props.page, info, onPage: (page) => table.dispatch({ type: 'setPage', page }) });
  if (props.selected) bridgeSelection({ selected: props.selected, selection: () => state().selection, onSelection: (keys) => table.dispatch({ type: 'setSelection', keys }) });

  const filterKey = props.filterKey ?? props.columns[0].key;
  const hidden = props.hiddenColumns ?? signal<string[]>([]); // 隐藏列键集：外部没给就自己持有
  const shown = computed(() => props.columns.filter((c) => !hidden().includes(c.key))); // 可见列：表头 / 单元格 / 导出 / colspan 全从这一处派生
  const span = (): number => shown().length + (selectable ? 1 : 0); // 跨列数随可见列变化

  // —— 表头全选框：checked / indeterminate 三态跟随当页选中情况 ——
  const headCheck = h('input', { type: 'checkbox', class: 'ua-checkbox' }) as HTMLInputElement;
  headCheck.addEventListener('change', () => {
    if (headCheck.checked) api.selectAllVisible();
    else table.dispatch({ type: 'clearSelection' });
  });
  effect(() => {
    const keys = visible().keys;
    const sel = state().selection;
    const onPage = keys.filter((k) => sel.includes(k)).length;
    headCheck.checked = keys.length > 0 && onPage === keys.length;
    headCheck.indeterminate = onPage > 0 && onPage < keys.length;
  });

  /*** 排序标记：升 ↑ / 降 ↓ / 未排序 ↕（可点击提示） ***/
  const sortMark = (key: string) =>
    h(
      'span',
      { class: 'ua-sort-mark' },
      () => {
        const rule = state().sorting.find((r) => r.key === key);
        return rule ? (rule.dir === 'asc' ? '↑' : '↓') : '↕';
      },
    );

  const th = (col: (typeof props.columns)[number]) => {
    const toggle = () => col.sortable && table.dispatch({ type: 'toggleSort', key: col.key }); // 鼠标与键盘共用的排序入口
    const el = h(
      'th',
      {
        class: `${col.sortable ? 'ua-sortable' : ''}${col.align ? ` ua-align-${col.align}` : ''}`.trim(),
        scope: 'col', // 表头单元格语义：读屏据此把列标题与数据格关联
        tabindex: col.sortable ? '0' : null, // 可排序表头进 Tab 序，不可排序的不抢焦点
        onClick: toggle,
        onKeydown: (e: KeyboardEvent) => {
          if (e.key === 'Enter' || e.key === ' ') { e.preventDefault(); toggle(); } // Enter / 空格 等价鼠标点击
        },
      },
      col.header ?? col.key,
      col.sortable ? sortMark(col.key) : null,
    );
    if (typeof col.width === 'number') attachResize(el, colEls.get(col.key)!, col.width, String(col.header ?? col.key)); // 定宽列可拖拽
    if (col.sortable) {
      effect(() => {
        const rule = state().sorting.find((r) => r.key === col.key); // 与视觉箭头同源
        el.setAttribute('aria-sort', rule ? (rule.dir === 'asc' ? 'ascending' : 'descending') : 'none');
      });
    }
    return el;
  };

  /*** 骨架行：列宽与表头对齐，行数取当前每页条数（上限 6 行防过长） ***/
  const skeletonRows = (): Node[] => {
    const count = Math.min(props.pageSize ?? 5, 6);
    const cell = () => h('td', null, skeleton({ variant: 'text', rows: 1 }));
    return Array.from({ length: count }, () => h('tr', { class: 'ua-loading-row' }, ...Array.from({ length: span() }, cell)));
  };

  const tbody = h('tbody');
  renderList(tbody, () => {
    if (busy()) return skeletonRows(); // 加载态优先：不看数据，避免闪出旧行
    const sel = state().selection; // 读入依赖：选择变化即整表重绘（行数 = pageSize，代价可控）
    const rows = visible().rows;
    if (!rows.length) return [emptyRow(span(), keyword, () => table.dispatch({ type: 'setFilter', key: filterKey, value: '' }), props.emptyText)]; // 空状态：筛选词与内核筛选一起清
    return rows.map((row, i) => {
      const key = visible().keys[i];
      const selected = sel.includes(key);
      const cells = shown().map((col) => {
        const raw = table.getCellValue(row, col.key);
        const text = col.format ? col.format(raw, row) : String(raw); // format 只产出纯文本，天然免注入
        return h('td', col.align ? { class: `ua-align-${col.align}` } : null, text);
      });
      if (selectable) {
        const check = h('input', { type: 'checkbox', class: 'ua-checkbox' }) as HTMLInputElement; // 受控：选中态由内核 selection 决定
        check.checked = selected;
        check.addEventListener('change', () => table.dispatch({ type: 'toggleSelect', key }));
        cells.unshift(h('td', { class: 'ua-cell-check' }, check));
      }
      const rowProps = props.onRowClick // 传了才把整行做成可聚焦按钮语义（Tab 进入、Enter / 空格触发）
        ? { tabindex: '0', class: `ua-row-clickable${selected ? ' ua-row-selected' : ''}`, onclick: () => props.onRowClick?.(row), onkeydown: (e: KeyboardEvent) => { if (e.key === 'Enter' || e.key === ' ') { e.preventDefault(); props.onRowClick?.(row); } } }
        : selected ? { class: 'ua-row-selected' } : null;
      return h('tr', rowProps, ...cells);
    });
  });
  // —— 列宽：数字落成 <col> 固定宽度，'flex' 或未设置交给浏览器自适应；按列键建一次，显隐只切换是否挂进 colgroup ——
  const colEls = new Map(props.columns.map((col) => [col.key, typeof col.width === 'number' ? h('col', { style: `width:${col.width}px` }) : h('col')])); // 复用同一批 <col>，拖拽改的宽度不因显隐丢失
  const colgroup = h('colgroup');
  renderList(colgroup, () => [...(selectable ? [h('col', { style: 'width:44px' })] : []), ...shown().map((c) => colEls.get(c.key)!)]);

  const filterInput = textField({
    placeholder: `筛选 ${filterKey}…`,
    prefix: iconSearch(),
    value: keyword, // 受控信号：空状态里的「清除筛选」能同时清掉输入框内容
    disabled: props.loading, // 加载中禁止筛选，避免与在途结果竞争
    onInput: (value) => {
      table.dispatch({ type: 'setFilter', key: filterKey, value });
      table.dispatch({ type: 'setPage', page: 1 }); // 筛选变化回第 1 页
    },
  });

  // —— 表头：随可见列重绘（隐藏列既不占表头也不占单元格） ——
  const thead = h('thead');
  renderList(thead, () => [h('tr', null, ...(selectable ? [headCheck] : []), ...shown().map(th))]);

  return h(
    'section',
    { class: 'ua-table', 'aria-busy': () => String(busy()) },
    h(
      'div',
      { class: 'ua-table-toolbar' },
      filterInput,
      selectable ? h('span', { class: 'ua-sel-count' }, () => (selectedCount() ? `已选 ${selectedCount()} 行` : '')) : null,
      props.columnToggle ? columnPicker({ columns: props.columns, hidden, disabled: busy }) : null, // 列显隐面板：勾选即重绘表头与单元格
      props.exportable ? exportButton(table, () => shown(), props.exportName ?? 'table.csv') : null, // 导出筛选+排序后的全量行，列跟随当前可见列
    ),
    h('div', { class: 'ua-table-scroll' }, h('table', null, colgroup, thead, tbody)),
    tablePager({
      info,
      total: () => visible().total,
      loading: busy,
      pageSizes: props.pageSizes,
      onPage: (page) => table.dispatch({ type: 'setPage', page }),
      onPageSize: (pageSize) => table.dispatch({ type: 'setPageSize', pageSize }),
    }),
  );
}