import { useMemo, useRef, useState, useCallback } from "react";
import { useNavigate } from "react-router-dom";

import { useCourses } from "@/contexts/AdminCoursesContext";
import { useAuth } from "@/contexts/AuthContext";

import DataTable from "@/components/generic/Table/DataTable";
import { FilterSheet } from "@/components/generic/Sheet/FilterSheet";
import { ArchiveDialog } from "@/components/generic/Dialogs/ArchiveDialog";

import { buildDataColumns, columnPinning } from "../../config/courses/units/columns.config";
import { buildToolbarActions } from "../../config/courses/units/toolbar.config";
import { buildSelectionActions } from "../../config/courses/units/selection.config";
import { buildRowActions } from "../../config/courses/units/rowActions.config";

import { getTimestamp } from "@/utils/timestamp.util";

export default function UnitsTable({ courseId }) {
  const [archiveTarget, setArchiveTarget] = useState(null);
  const [archiveIds, setArchiveIds] = useState(null);

  const tableRefsRef = useRef({
    getFilters: () => [],
    getSort: () => [],
    resetSelection: () => { },
    setFilters: () => { },
  });

  const navigate = useNavigate();

  const {
    course, units, attributes, pagination, setPagination, loading,
    fetchUnits, archiveUnit, archiveUnits, fetchUnitFieldValues
  } = useCourses();

  const handleRefsReady = (refs) => {
    tableRefsRef.current = refs;
  };

  const exportConfig = {
    allData: units,
    attributes,
    filename: `${getTimestamp()}_${course?.title}_Units`,
    sheetName: "Units",
  };

  const handleFetch = useCallback(
    (params) => fetchUnits(courseId, params),
    [courseId]
  );

  const rowActions = useMemo(() => buildRowActions({
    onQuiz: (row) => navigate(`/admin/courses/${courseId}/units/${row.unit_id}/quiz`),
    onViewLessons: (row) => navigate(`/admin/courses/${courseId}/units/${row.unit_id}/lessons`),
    onView: (row) => navigate(`/admin/courses/${courseId}/units/${row.unit_id}/view`),
    onEdit: (row) => navigate(`/admin/courses/${courseId}/units/${row.unit_id}/edit`),
    onArchive: (row) => setArchiveTarget(row),
  }), [courseId]);

  const toolbarActions = buildToolbarActions({
    fetchUnits: (params) => fetchUnits(courseId, params),
    pagination,
    exportConfig,
    navigate,
    courseId,
    getFilters: () => tableRefsRef.current.getFilters(),
    getSort: () => tableRefsRef.current.getSort(),
    getTableInstance: () => tableRefsRef.current.tableInstance,
  });

  const selectionActions = buildSelectionActions({
    exportConfig,
    onArchive: (row) => setArchiveTarget(row),
    onArchiveMany: (ids) => setArchiveIds(ids),
    getTableInstance: () => tableRefsRef.current.tableInstance,
  });

  const columns = useMemo(
    () => buildDataColumns(attributes, rowActions),
    [attributes, rowActions]
  );

  const handleArchiveSuccess = () => {
    setArchiveTarget(null);
    setArchiveIds(null);
    tableRefsRef.current.resetSelection?.();
    fetchUnits(courseId, { page: 1, limit: pagination?.limit ?? 10 });
  };

  return (
    <>
      <DataTable
        title="Units"
        data={units}
        columns={columns}
        attributes={attributes}
        pagination={pagination}
        setPagination={setPagination}
        loading={loading}
        onFetch={handleFetch}
        onFetchFilterData={(field) => fetchUnitFieldValues(courseId, field)}
        onRefsReady={handleRefsReady}
        renderFilterSheet={({ open, onOpenChange, column, attr, data, loading }) => (
          <FilterSheet
            open={open}
            onOpenChange={onOpenChange}
            column={column}
            attr={attr}
            data={data}
            loading={loading}
          />
        )}
        columnPinning={columnPinning}
        toolbarActions={toolbarActions}
        selectionActions={selectionActions}
        recordLabel="unit"
        emptyMessage="No units found."
      />

      {/* ── Single archive ── */}
      <ArchiveDialog
        open={!!archiveTarget}
        onOpenChange={(v) => !v && setArchiveTarget(null)}
        entity={archiveTarget}
        entityLabel="Unit"
        getName={(c) => c?.title}
        onArchive={(c) => archiveUnit(courseId, c?.unit_id)}
        loading={loading}
        onSuccess={handleArchiveSuccess}
      />

      {/* ── Bulk archive ── */}
      <ArchiveDialog
        open={!!archiveIds}
        onOpenChange={(v) => !v && setArchiveIds(null)}
        ids={archiveIds ?? []}
        entityLabel="Unit"
        onArchive={(ids) => archiveUnits(courseId, ids)}
        loading={loading}
        onSuccess={handleArchiveSuccess}
      />
    </>
  );
}