// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'package:flutter/material.dart';
import 'package:two_dimensional_scrollables/two_dimensional_scrollables.dart';

/// The class demonstrating merged cells in TableView.
class MergedTableExample extends StatefulWidget {
  /// Creates a screen that shows a color palette in the TableView widget.
  const MergedTableExample({super.key});

  @override
  State<MergedTableExample> createState() => _MergedTableExampleState();
}

class _MergedTableExampleState extends State<MergedTableExample> {
  @override
  Widget build(BuildContext context) {
    final Size screenSize = MediaQuery.sizeOf(context);
    return Scaffold(
      body: Padding(
        padding: EdgeInsets.symmetric(horizontal: screenSize.width * 0),
        child: TableView.builder(
          cellBuilder: _buildCell,
          columnCount: 1000,
          pinnedColumnCount: 1,
          columnBuilder: _buildColumnSpan,
          rowCount: 51,
          rowBuilder: _buildRowSpan,
        ),
      ),
    );
  }

  TableViewCell _buildCell(BuildContext context, TableVicinity vicinity) {
    final int colorIndex = (vicinity.row / 3).floor();
    final TextStyle style = TextStyle(
      color: Colors.black,
      fontSize: 18.0,
      fontWeight: vicinity.column == 0 ? FontWeight.bold : null,
    );
    return TableViewCell(
      rowMergeStart: vicinity.column == 0 ? colorIndex * 3 : null,
      rowMergeSpan: vicinity.column == 0 ? 3 : null,
      columnMergeStart: vicinity.column == 1 ? vicinity.column : null,
      columnMergeSpan: vicinity.column == 1 ? 3 : null,
      child: ColoredBox(
        color: Colors.grey,
        child: Center(child: Text('cell.name', style: style)),
      ),
    );
  }

  TableSpan _buildColumnSpan(int index) {
    return TableSpan(
      extent: FixedTableSpanExtent(index == 0 ? 220 : 50),
      foregroundDecoration: index == 0
          ? const TableSpanDecoration(
              border: TableSpanBorder(
                trailing: BorderSide(width: 5, color: Colors.white),
              ),
            )
          : null,
    );
  }

  TableSpan _buildRowSpan(int index) {
    return TableSpan(
      extent: const FixedTableSpanExtent(120),
      padding: index % 3 == 0 ? const TableSpanPadding(leading: 5.0) : null,
    );
  }
}