import 'package:flutter/material.dart';
import '../about/internal/application/TextType.dart';

import '../about/internal/application/DeploymentRecord.dart';
import '../utils/Colors.dart';
import 'text/Text.dart';

enum _Range { week, month, year }

class _Bucket {
  final String label;
  final int count;
  _Bucket(this.label, this.count);
}

/// "Compute Activity" style card: a bar chart of deployment counts over time,
/// with the peak column highlighted, and a Week / Month / Year toggle.
class ActivityChart extends StatefulWidget {
  final List<DeploymentRecord> history;
  const ActivityChart({super.key, required this.history});

  @override
  State<ActivityChart> createState() => _ActivityChartState();
}

class _ActivityChartState extends State<ActivityChart> {
  _Range _range = _Range.week;

  List<_Bucket> _buckets() {
    final now = DateTime.now();
    final h = widget.history;
    int between(DateTime a, DateTime b) =>
        h.where((r) => !r.time.isBefore(a) && r.time.isBefore(b)).length;
    const wd = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun'];
    const mo = [
      'Jan',
      'Feb',
      'Mar',
      'Apr',
      'May',
      'Jun',
      'Jul',
      'Aug',
      'Sep',
      'Oct',
      'Nov',
      'Dec',
    ];
    switch (_range) {
      case _Range.week:
        final today = DateTime(now.year, now.month, now.day);
        return List.generate(7, (i) {
          final d = today.subtract(Duration(days: 6 - i));
          return _Bucket(
            wd[d.weekday - 1],
            between(d, d.add(const Duration(days: 1))),
          );
        });
      case _Range.month:
        // last 6 weeks
        final startOfWeek = DateTime(
          now.year,
          now.month,
          now.day,
        ).subtract(Duration(days: now.weekday - 1));
        return List.generate(6, (i) {
          final s = startOfWeek.subtract(Duration(days: (5 - i) * 7));
          final e = s.add(const Duration(days: 7));
          return _Bucket('${s.month}/${s.day}', between(s, e));
        });
      case _Range.year:
        // last 6 months
        return List.generate(6, (i) {
          final m = DateTime(now.year, now.month - (5 - i), 1);
          final next = DateTime(m.year, m.month + 1, 1);
          return _Bucket(mo[m.month - 1], between(m, next));
        });
    }
  }

  @override
  Widget build(BuildContext context) {
    final jp = context.jp;
    final buckets = _buckets();
    final max = buckets.fold(0, (m, b) => b.count > m ? b.count : m);
    final peakIdx = buckets.indexWhere((b) => b.count == max && max > 0);
    final total = buckets.fold(0, (n, b) => n + b.count);
    return Container(
      padding: const EdgeInsets.all(18),
      decoration: PeachTheme.panel(context),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            children: [
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    text(
                      'Deployment activity',
                      16,
                      TextType.Bold,
                      color: jp.text,
                      weight: FontWeight.w800,
                    ),
                    const SizedBox(height: 2),
                    text(
                      '$total deploys this period',
                      12.5,
                      TextType.Regular,
                      color: jp.textDim,
                      weight: FontWeight.w400,
                    ),
                  ],
                ),
              ),
              _toggle(jp),
            ],
          ),
          const SizedBox(height: 20),
          SizedBox(
            height: 190,
            child: Row(
              crossAxisAlignment: CrossAxisAlignment.end,
              children: [
                for (var i = 0; i < buckets.length; i++)
                  Expanded(child: _bar(jp, buckets[i], max, i == peakIdx)),
              ],
            ),
          ),
        ],
      ),
    );
  }

  Widget _bar(JpColors jp, _Bucket b, int max, bool peak) {
    final frac = max == 0 ? 0.0 : b.count / max;
    final h = 12 + frac * 130;
    return Column(
      mainAxisAlignment: MainAxisAlignment.end,
      children: [
        text(
          '${b.count}',
          12,
          TextType.Regular,
          color: peak ? PeachTheme.seed : jp.textDim,
          weight: FontWeight.w800,
        ),
        const SizedBox(height: 6),
        Container(
          width: 26,
          height: h,
          decoration: BoxDecoration(
            gradient: peak ? PeachTheme.brandGradient : null,
            color: peak ? null : jp.surface2,
            borderRadius: BorderRadius.circular(9),
            boxShadow: peak
                ? PeachTheme.glow(PeachTheme.seed, opacity: 0.35, blur: 16)
                : null,
          ),
        ),
        const SizedBox(height: 8),
        text(
          b.label,
          11,
          TextType.Regular,
          color: peak ? jp.text : jp.textFaint,
          maxLines: 1,
          overflow: TextOverflow.clip,
          weight: peak ? FontWeight.w700 : FontWeight.w500,
        ),
      ],
    );
  }

  Widget _toggle(JpColors jp) {
    Widget seg(_Range r, String label) {
      final active = _range == r;
      return GestureDetector(
        onTap: () => setState(() => _range = r),
        child: Container(
          padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 7),
          decoration: BoxDecoration(
            color: active ? jp.surface : Colors.transparent,
            borderRadius: BorderRadius.circular(9),
            boxShadow: active
                ? [
                    BoxShadow(
                      color: Colors.black.withValues(alpha: 0.08),
                      blurRadius: 6,
                      offset: const Offset(0, 2),
                    ),
                  ]
                : null,
          ),
          child: text(
            label,
            12.5,
            TextType.Regular,
            color: active ? jp.text : jp.textDim,
            weight: active ? FontWeight.w700 : FontWeight.w500,
          ),
        ),
      );
    }

    return Container(
      padding: const EdgeInsets.all(4),
      decoration: BoxDecoration(
        color: jp.surface2,
        borderRadius: BorderRadius.circular(12),
      ),
      child: Row(
        mainAxisSize: MainAxisSize.min,
        children: [
          seg(_Range.week, 'Week'),
          seg(_Range.month, 'Month'),
          seg(_Range.year, 'Year'),
        ],
      ),
    );
  }
}