import { useLayoutEffect, useMemo, useRef, useState } from "react";
import { Table } from "antd";
import Icon, { FilterFilled, FilterOutlined } from "@ant-design/icons";
import type { ColumnGroupType, ColumnsType, ColumnType } from "antd/es/table";
import type { TableProps } from "antd";
import { CustomFilterDropdown } from "./CustomFilterDropdown";
import { Highlight } from "./Highlight";
import {
  isGroup,
  LeafColumnDef,
  type ColumnFilters,
  type FilterOption,
  type SortState,
  type TableConfig,
} from "./tableTypes";
type ExtraColumn<T> = ColumnType<T> & {
  position?: number | "start" | "end";
  afterKey?: Extract<keyof T, string>;
};
interface DataTableProps<T extends Record<string, any>> {
  config: TableConfig<T>;
  rows: T[];
  allRows: T[];
  loading?: boolean;
  visibleKeys: Array<Extract<keyof T, string>>;
  globalQuery?: string;
  columnFilters: ColumnFilters<T>;
  onColumnFiltersChange: (next: ColumnFilters<T>) => void;
  sortState: SortState<T>;
  onSortChange: (next: SortState<T>) => void;
  extraColumns?: ColumnsType<T>;
  rowSelection?: TableProps<T>["rowSelection"];
  scrollY?: number | string;
  onRow?: TableProps<T>["onRow"];
}

export function DataTable<T extends Record<string, any>>({
  config,
  rows,
  allRows,
  loading,
  visibleKeys,
  globalQuery = "",
  columnFilters,
  onColumnFiltersChange,
  sortState,
  onSortChange,
  extraColumns = [],
  rowSelection,
  scrollY = 480,
  onRow,
}: DataTableProps<T>) {
  const { columns: defs, searchableKeys = [], rowKey } = config;
  const normalizedQuery = globalQuery.trim().toLowerCase();
  const hasGlobalSearch =
    searchableKeys.length > 0 && normalizedQuery.length > 0;

  const getOptions = (key: Extract<keyof T, string>): FilterOption[] => {
    const seen = new Set<string | number>();
    const opts: FilterOption[] = [];
    for (const r of allRows) {
      const v = r[key];
      if (!seen.has(v)) {
        seen.add(v);
        opts.push({ label: String(v), value: v });
      }
    }
    return opts;
  };

  const buildLeaf = (def: LeafColumnDef<T>): ColumnType<T> => {
    const { key, title, features = {}, render, width, fixed } = def;
    const hasDropdown =
      features.multiselect || features.search || features.sort;
    const isSearchable = searchableKeys.includes(key);
    return {
      key,
      title,
      dataIndex: key,
      width,
      fixed,
      render: (value: T[keyof T], row: T) => {
        if (render) return render(value, row);
        const text = String(value ?? "");
        return isSearchable && hasGlobalSearch ? (
          <Highlight text={text} query={globalQuery.trim()} />
        ) : (
          text
        );
      },
      ...(hasDropdown
        ? {
            filterIcon: () => {
              const active =
                (columnFilters[key]?.length ?? 0) > 0 || sortState?.key === key;
              return (
                <span
                  style={{
                    display: "inline-flex",
                    alignItems: "center",
                    justifyContent: "center",
                    padding: "4px 6px",
                    borderRadius: 6,
                    background: active
                      ? "rgba(245, 158, 11, 0.14)"
                      : "transparent",
                    color: active ? "rgb(22, 101, 52)" : "#bfbfbf",
                    transition: "background 0.15s",
                  }}
                >
                  <FilterOutlined style={{ fontSize: 12 }} />
                </span>
              );
            },
            filterDropdown: ({ confirm, clearFilters }) => (
              <CustomFilterDropdown
                selectedKeys={(columnFilters[key] ?? []) as React.Key[]}
                setSelectedKeys={(keys) =>
                  onColumnFiltersChange({
                    ...columnFilters,
                    [key]: keys as (string | number)[],
                  })
                }
                confirm={confirm}
                clearFilters={clearFilters}
                features={features}
                options={
                  features.multiselect || features.search ? getOptions(key) : []
                }
                sortDirection={sortState?.key === key ? sortState.dir : null}
                onSort={(dir) => onSortChange(dir ? { key, dir } : null)}
              />
            ),
          }
        : {}),
    };
  };
  const columns: ColumnsType<T> = useMemo(() => {
    const built: ColumnsType<T> = [];
    for (const def of defs) {
      if (isGroup(def)) {
        const visibleChildren = def.children.filter((c) =>
          visibleKeys.includes(c.key),
        );
        if (visibleChildren.length === 0) continue;
        built.push({
          key: def.groupKey,
          title: def.title,
          fixed: def.fixed,
          children: visibleChildren.map(buildLeaf),
        } as ColumnGroupType<T>);
      } else {
        if (!visibleKeys.includes(def.key)) continue;
        built.push(buildLeaf(def));
      }
    }
    for (const col of extraColumns) {
      const { position, afterKey, ...rest } = col as ExtraColumn<T> & {
        position?: any;
        afterKey?: any;
      };
      let idx: number;
      if (afterKey) {
        const f = built.findIndex(
          (c: any) => c.key === afterKey || c.dataIndex === afterKey,
        );
        idx = f === -1 ? built.length : f + 1;
      } else if (position === "start") idx = 0;
      else if (position === "end" || position === undefined) idx = built.length;
      else idx = Math.max(0, Math.min(position, built.length));
      built.splice(idx, 0, rest as ColumnsType<T>[number]);
    }
    return built;
  }, [
    defs,
    visibleKeys,
    sortState,
    allRows,
    searchableKeys,
    globalQuery,
    hasGlobalSearch,
    columnFilters,
    onColumnFiltersChange,
    onSortChange,
    extraColumns,
  ]);

  const wrapperRef = useRef<HTMLDivElement>(null);
  const [appliedScrollY, setAppliedScrollY] = useState(scrollY);

  useLayoutEffect(() => {
    const wrapper = wrapperRef.current;
    if (!wrapper) return;

    const update = () => {
      const total = wrapper.clientHeight;

      const header = wrapper.querySelector<HTMLElement>(".ant-table-thead");
      const headerH = header?.offsetHeight ?? 55;
      setAppliedScrollY(Math.max(0, total - headerH));
    };

    update();
    const ro = new ResizeObserver(update);
    ro.observe(wrapper);
    return () => ro.disconnect();
  }, []);

  return (
    <div ref={wrapperRef} style={{ flex: 1, height: "100%" }}>
      <Table<T>
        rowKey={rowKey}
        loading={loading}
        columns={columns}
        dataSource={rows}
        rowSelection={rowSelection}
        pagination={false}
        scroll={{ x: "max-content", y: appliedScrollY }}
        onRow={onRow}
      />
    </div>
  );
}