import 'package:flutter/material.dart';

import 'claims_overview_scope.dart';

/// Horizontal panel row for dashboard tabs; uses fixed widths during PDF capture.
class ClaimsTabPanelRow extends StatelessWidget {
  final List<ClaimsTabPanel> panels;
  final double gap;
  final CrossAxisAlignment crossAxisAlignment;

  const ClaimsTabPanelRow({
    super.key,
    required this.panels,
    this.gap = 16,
    this.crossAxisAlignment = CrossAxisAlignment.start,
  });

  @override
  Widget build(BuildContext context) {
    final laneWidth = ClaimsPdfExportScope.laneWidthOf(context);
    final isPdf = ClaimsPdfExportScope.of(context) && laneWidth != null;

    if (!isPdf) {
      return Row(
        crossAxisAlignment: crossAxisAlignment,
        children: _withGaps(
          panels
              .map((p) => Expanded(flex: p.flex, child: p.child))
              .toList(),
        ),
      );
    }

    final totalFlex = panels.fold<int>(0, (sum, p) => sum + p.flex);
    final gaps = gap * (panels.length - 1);
    final available = laneWidth! - gaps;

    return Row(
      crossAxisAlignment: crossAxisAlignment,
      children: _withGaps(
        panels.map((p) {
          return SizedBox(
            width: available * p.flex / totalFlex,
            child: p.child,
          );
        }).toList(),
      ),
    );
  }

  List<Widget> _withGaps(List<Widget> children) {
    if (children.isEmpty) return const [];
    final out = <Widget>[children.first];
    for (var i = 1; i < children.length; i++) {
      out.add(SizedBox(width: gap));
      out.add(children[i]);
    }
    return out;
  }
}

class ClaimsTabPanel {
  final int flex;
  final Widget child;

  const ClaimsTabPanel({required this.flex, required this.child});
}

/// Mini grid for metric tiles inside section cards.
class ClaimsTabMiniGrid extends StatelessWidget {
  final List<Widget> items;
  final double gap;
  final int columns;

  const ClaimsTabMiniGrid({
    super.key,
    required this.items,
    this.gap = 8,
    this.columns = 2,
  });

  @override
  Widget build(BuildContext context) {
    assert(items.length == 3 || items.length == 4);
    assert(columns == 2 || (columns == 3 && items.length == 3));

    return LayoutBuilder(
      builder: (context, constraints) {
        final maxW = constraints.maxWidth;
        final isPdf = ClaimsPdfExportScope.of(context);

        Widget cell(int index, {bool fullWidth = false, int? rowColumns}) {
          final child = items[index];
          if (isPdf && maxW.isFinite) {
            final cols = rowColumns ?? columns;
            final width = fullWidth
                ? maxW
                : (maxW - gap * (cols - 1)) / cols;
            return SizedBox(width: width, child: child);
          }
          return Expanded(child: child);
        }

        if (items.length == 3 && columns == 3) {
          return Row(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              cell(0, rowColumns: 3),
              SizedBox(width: gap),
              cell(1, rowColumns: 3),
              SizedBox(width: gap),
              cell(2, rowColumns: 3),
            ],
          );
        }

        if (items.length == 3) {
          return Column(
            mainAxisSize: MainAxisSize.min,
            children: [
              Row(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  cell(0),
                  SizedBox(width: gap),
                  cell(1),
                ],
              ),
              SizedBox(height: gap),
              Row(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [cell(2, fullWidth: true)],
              ),
            ],
          );
        }

        return Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            Row(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                cell(0),
                SizedBox(width: gap),
                cell(1),
              ],
            ),
            SizedBox(height: gap),
            Row(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                cell(2),
                SizedBox(width: gap),
                cell(3),
              ],
            ),
          ],
        );
      },
    );
  }
}