WeatherMaster/lib/widgets/rain_block.dart

import 'package:flutter/material.dart';
import 'package:intl/intl.dart';
import 'package:fl_chart/fl_chart.dart';
import '../notifiers/unit_settings_notifier.dart';
import '../utils/unit_converter.dart';
import 'package:provider/provider.dart';

class RainBlock extends StatelessWidget {
  final List<String> hourlyTime;
  final List<double> hourlyPrecp;
  final List<dynamic> hourlyPrecpProb;
  final int selectedContainerBgIndex;
 final String timezone;
 final String utcOffsetSeconds;

  const RainBlock({
    super.key,
    required this.hourlyTime,
    required this.hourlyPrecp,
    required this.selectedContainerBgIndex,
    required this.timezone,
    required this.utcOffsetSeconds,
    required this.hourlyPrecpProb
  });

  

int get _currentIndex {
    int offsetSeconds = int.parse(utcOffsetSeconds);
    DateTime utcNow = DateTime.now().toUtc();
    DateTime now = utcNow.add(Duration(seconds: offsetSeconds));


    now = DateTime(
      now.year,
      now.month,
      now.day,
      now.hour,
      now.minute,
      now.second,
      now.millisecond,
      now.microsecond,
    );


  for (int i = 0; i < hourlyTime.length; i++) {
    final dt = DateTime.parse(hourlyTime[i]);
    if (!dt.isBefore(now)) return i;
  }
  return 0; // fallback if all are in the past
}

List<String> get next12Time => hourlyTime.skip(_currentIndex).take(12).toList();
List<double> get next12Precp => hourlyPrecp.skip(_currentIndex).take(12).toList();

List<String> get next12TimeProb => hourlyTime.skip(_currentIndex).take(12).toList();
List get next12PrecpProb => hourlyPrecpProb.skip(_currentIndex).take(12).toList();


  double get maxRain {
    final r = next12Precp.reduce((a, b) => a > b ? a : b);
    return (r < 3) ? 3 : (r * 1.3).ceilToDouble();
  }

(int?, int?) getRainPeriod() {
  int? bestStart;
  int? bestEnd;
  int longestLength = 0;

  int? currentStart;

  for (int i = 0; i < next12Precp.length; i++) {
     final double precp = next12Precp[i];
     final int prob = next12PrecpProb[i] ?? 0;
    if (precp > 0.2 && prob >= 40) {
      currentStart ??= i;
    } else {
      if (currentStart != null) {
        final length = i - currentStart;
        if (length >= 2 && length > longestLength) {
          bestStart = currentStart;
          bestEnd = i - 1;
          longestLength = length;
        }
        currentStart = null; // reset
      }
    }
  }

  if (currentStart != null) {
    final length = next12Precp.length - currentStart;
    if (length >= 2 && length > longestLength) {
      bestStart = currentStart;
      bestEnd = next12Precp.length - 1;
    }
  }

  return (bestStart, bestEnd);
}

String _generateTitle(int? start) {
  if (start == null) return "No rain expected";

  if (start == 0 && next12Precp[0] > 0.2) {
    return willRainStopSoon() ? "Rain will stop soon" : "It's currently raining";
  }

  final hour = DateTime.parse(next12Time[start]).hour;

  if (hour >= 0 && hour <= 5) return "Rain expected overnight";
  if (hour >= 6 && hour < 12) return "Rain expected this morning";
  if (hour >= 12 && hour < 17) return "Rain expected this afternoon";
  if (hour >= 17 && hour <= 22) return "Rain expected this evening";

  return "Rain expected later today";
}



bool willRainStopSoon() {
  if (next12Precp[0] <= 0.2 || (next12PrecpProb[0] ?? 0) < 30) return false;

  int dryCount = 0;
  for (int i = 1; i < next12Precp.length; i++) {
    final double precp = next12Precp[i];
    final int prob = next12PrecpProb[i] ?? 0;

    if (precp <= 0.2 || prob < 30) {
      dryCount++;
      if (dryCount >= 2) return true;
    } else {
      dryCount = 0;
    }
  }
  return false;
}



  Color _barColor(double mm, context) {
    if (mm > 5) return Theme.of(context).colorScheme.error;
    if (mm > 2) return Theme.of(context).colorScheme.tertiary;
    if (mm > 0.2) return Theme.of(context).colorScheme.primary;
    return Theme.of(context).colorScheme.primary;
  }

  @override
  Widget build(BuildContext context) {

  String? generateSummary(int? start, int? end) {
    if (start == null || end == null) return null;

    final segment = next12Precp.sublist(start, end + 1);
    final max = segment.reduce((a, b) => a > b ? a : b);

    String label = switch (max) {
      > 5 => "Heavy rain",
      > 2 => "Moderate rain",
      _ => "Light rain"
    };

    final timeUnit = context.watch<UnitSettingsNotifier>().timeUnit;


    final startStr = timeUnit == '24 hr' ? DateFormat.Hm().format(DateTime.parse(next12Time[start])) :  DateFormat.jm().format(DateTime.parse(next12Time[start]));
    final endStr = timeUnit == '24 hr' ? DateFormat.Hm().format(DateTime.parse(next12Time[end])) :  DateFormat.jm().format(DateTime.parse(next12Time[end]));

    return "$label from $startStr to $endStr";
  }


    final (start, end) = getRainPeriod();
    final title = _generateTitle(start);
    final subtitle = generateSummary(start, end);
    final rain = next12Precp;
    final unitSettings = Provider.of<UnitSettingsNotifier>(context, listen: false);
    final precipitationUnit = unitSettings.precipitationUnit;


    return Container(
      margin: const EdgeInsets.only(bottom: 0, left: 12, right: 12, top: 0),
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: Color(selectedContainerBgIndex),
        borderRadius: BorderRadius.circular(18),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(title, style: TextStyle(color: Theme.of(context).colorScheme.onSurface, fontSize: 16, fontWeight: FontWeight.w500)),
          if (subtitle != null)
            Padding(
              padding: const EdgeInsets.only(top: 2),
              child: Text(subtitle, style: TextStyle(color: Theme.of(context).colorScheme.onSurfaceVariant, fontSize: 13)),
            ),
          const SizedBox(height: 16),

  SizedBox(
  height: 90,
  child: BarChart(
    
    BarChartData(
      alignment: BarChartAlignment.start,
      maxY: maxRain,
      barTouchData: BarTouchData(enabled: true,
      touchTooltipData: BarTouchTooltipData(
        tooltipBorderRadius: BorderRadius.circular(50),
        getTooltipColor: (group) => Theme.of(context).colorScheme.primaryContainer,
        tooltipPadding: EdgeInsets.only(left: 5, right: 5),
        getTooltipItem: (group, groupIndex, rod, rodIndex) {
      final convertedPrecip = precipitationUnit == 'cm'
          ? UnitConverter.mmToCm(rod.toY)
          : precipitationUnit == 'in'
              ? UnitConverter.mmToIn(rod.toY)
              : rod.toY;
        return BarTooltipItem(
          '${convertedPrecip.toStringAsFixed(1)} $precipitationUnit',
           TextStyle(color: Theme.of(context).colorScheme.onPrimaryContainer, fontWeight: FontWeight.w500),
           
        );
      },
    ),
  ),
      
      borderData: FlBorderData(
      show: true,
      border: Border(
      bottom: BorderSide(
        color: Theme.of(context).colorScheme.outlineVariant, 
        width: 1,        
      ),
    ),
    ),
      gridData: FlGridData(
        show: true,
        drawHorizontalLine: true,
      
        drawVerticalLine: false,
        horizontalInterval: maxRain / 3,
        getDrawingHorizontalLine: (_) => FlLine(
          color: Theme.of(context).colorScheme.outlineVariant,
          strokeWidth: 1,
        ),

      ),
      titlesData: FlTitlesData(
        topTitles: AxisTitles(sideTitles: SideTitles(showTitles: false)),
        rightTitles: AxisTitles(sideTitles: SideTitles(showTitles: false)),
        
        leftTitles: AxisTitles(
          sideTitles: SideTitles(
            showTitles: true,
            
            reservedSize: 50,
          getTitlesWidget: (value, _) {
            final roundedMax = maxRain;
            final step = roundedMax / 2;
            final convertedPrecip = precipitationUnit == 'cm'
                ? UnitConverter.mmToCm(value)
                : precipitationUnit == 'in'
                    ? UnitConverter.mmToIn(value)
                    : value;

              if (value == 0 || value == step || value == roundedMax) {
                return Text(
                  '${double.parse(convertedPrecip.toStringAsFixed(1))} $precipitationUnit',
                  style: TextStyle(fontSize: 10, color: Theme.of(context).colorScheme.onSurfaceVariant),
                );
              }
              return const SizedBox.shrink();
            },
            interval: maxRain / 2,
          ),
        ),
        bottomTitles: AxisTitles(
          sideTitles: SideTitles(
            showTitles: true,
            reservedSize: 18,
            
            getTitlesWidget: (value, _) {
              final idx = value.toInt();
              if (idx % 3 != 0 || idx >= next12Time.length) return const SizedBox.shrink();
              final dt = DateTime.parse(next12Time[idx]);
              return
              Padding(padding: EdgeInsets.only(left: 8),
              child: Text(
                unitSettings.timeUnit == '24 hr' ? DateFormat.Hm().format(dt) : DateFormat.jm().format(dt),
                
                style: TextStyle(color: Theme.of(context).colorScheme.onSurfaceVariant, fontSize: 9),
              )
              );
            },
          ),
        ),
      ),
      barGroups: List.generate(rain.length, (i) {
        return BarChartGroupData(
          x: i,
          barRods: [
            BarChartRodData(
              toY: rain[i],
              width: 15,
              color: _barColor(rain[i], context),
              borderRadius: BorderRadius.only(topLeft: Radius.circular(50), topRight: Radius.circular(50)),
            ),
          ],
        );
      }),
    ),
  ),
),

          // ),
        ],
      ),
    );
  }
}