// Author: fruit.com.cn

import 'dart:async';

import 'package:flutter/material.dart';

import '../../core/data/models/reward.dart';
import '../../core/data/services/reward_controller.dart';
import '../../core/theme/app_colors.dart';
import '../../core/theme/app_dimens.dart';
import '../../l10n/app_localizations.dart';
import 'reward_checkin_card.dart';
import 'reward_visuals.dart';

const double _balanceLabelFont = 18;
const double _balanceFont = 36;
const double _sectionTitleFont = 20;
const double _sectionSubtitleFont = 13;
const double _taskRowMinHeight = 68;
const double _taskTitleFont = 15;
const double _taskSubtitleFont = 12;
const double _taskRewardFont = 14;
const double _taskButtonHeight = 36;
const double _taskButtonMinWidth = 80;
const double _taskButtonFont = 13;
const double _taskCardRadius = 14;
const double _taskCardBorderWidth = 1;
const Color _taskCardStart = Color(0xFF1A1A1C);
const Color _taskCardEnd = Color(0xFF101010);
const Color _taskCardBorder = Color(0xFF29292B);
const Color _mutedActionStart = Color(0xFF3C171C);
const Color _divider = Color(0xFF333336);
const String _checkInSectionCode = 'CHECK_IN';

/// 奖励任务内容，负责余额、签到卡与可配置任务列表。
class RewardTasksView extends StatelessWidget {
  const RewardTasksView({
    super.key,
    required this.l10n,
    required this.rewards,
    required this.overview,
    required this.onRefresh,
    required this.onCheckIn,
    required this.onTaskAction,
    this.onOpenWallet,
    this.onBoostCheckIn,
  });

  final AppLocalizations l10n;
  final RewardController rewards;
  final RewardOverview overview;
  final Future<void> Function() onRefresh;
  final Future<void> Function() onCheckIn;
  final Future<void> Function(RewardTask task) onTaskAction;
  final VoidCallback? onOpenWallet;
  final VoidCallback? onBoostCheckIn;

  @override
  Widget build(BuildContext context) {
    return RefreshIndicator(
      color: AppColors.brandRed,
      backgroundColor: AppColors.contentCard,
      onRefresh: onRefresh,
      child: ListView(
        physics: const AlwaysScrollableScrollPhysics(),
        padding: const EdgeInsets.fromLTRB(
          AppDimens.pageHorizontal,
          AppDimens.spaceLg,
          AppDimens.pageHorizontal,
          AppDimens.spaceXl,
        ),
        children: [
          _Balance(
            key: const Key('reward-balance'),
            balance: overview.coinBalance,
            onOpenWallet: onOpenWallet,
          ),
          const SizedBox(height: AppDimens.spaceLg),
          RewardCheckinCard(
            l10n: l10n,
            rewards: rewards,
            checkin: overview.checkin,
            onCheckIn: onCheckIn,
            onBoost: onBoostCheckIn ?? () {},
          ),
          for (final section in overview.sections)
            if (_isVisibleSection(section)) ...[
              const SizedBox(height: AppDimens.spaceXl),
              _SectionHeader(
                key: Key('reward-section-${section.code}'),
                l10n: l10n,
                section: section,
              ),
              const SizedBox(height: AppDimens.spaceMd),
              _TaskGroupCard(
                key: Key('reward-task-card-${section.code}'),
                l10n: l10n,
                rewards: rewards,
                section: section,
                onTaskAction: onTaskAction,
              ),
            ],
          if (!overview.sections.any(_isVisibleSection))
            _Empty(label: l10n.rewardEmptyTasks),
        ],
      ),
    );
  }
}

bool _isVisibleSection(RewardSection section) {
  return section.code.toUpperCase() != _checkInSectionCode &&
      section.tasks.isNotEmpty;
}

class _Balance extends StatelessWidget {
  const _Balance({super.key, required this.balance, this.onOpenWallet});

  final int balance;
  final VoidCallback? onOpenWallet;

  @override
  Widget build(BuildContext context) {
    final content = Row(
      crossAxisAlignment: CrossAxisAlignment.center,
      children: [
        Flexible(
          child: FittedBox(
            fit: BoxFit.scaleDown,
            alignment: Alignment.centerLeft,
            child: Text(
              AppLocalizations.of(context)!.rewardMyCoins,
              style: const TextStyle(
                color: AppColors.textSecondary,
                fontSize: _balanceLabelFont,
                fontWeight: FontWeight.w500,
              ),
            ),
          ),
        ),
        const SizedBox(width: AppDimens.spaceMd),
        Text(
          '$balance',
          style: const TextStyle(
            color: AppColors.textPrimary,
            fontSize: _balanceFont,
            fontWeight: FontWeight.w800,
            height: 1,
          ),
        ),
        const SizedBox(width: AppDimens.spaceSm),
        const RewardCoinIcon(key: Key('reward-balance-coin-icon'), size: 32),
      ],
    );
    if (onOpenWallet == null) return content;
    return InkWell(
      onTap: onOpenWallet,
      borderRadius: BorderRadius.circular(AppDimens.cardRadius),
      child: Padding(
        padding: const EdgeInsets.symmetric(vertical: AppDimens.spaceXs),
        child: content,
      ),
    );
  }
}

class _SectionHeader extends StatelessWidget {
  const _SectionHeader({super.key, required this.l10n, required this.section});

  final AppLocalizations l10n;
  final RewardSection section;

  @override
  Widget build(BuildContext context) {
    final subtitle = _sectionSubtitle(l10n, section.code);
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text(
          section.title,
          style: const TextStyle(
            color: AppColors.textPrimary,
            fontSize: _sectionTitleFont,
            fontWeight: FontWeight.w800,
          ),
        ),
        if (subtitle.isNotEmpty) ...[
          const SizedBox(height: AppDimens.spaceXs),
          Text(
            subtitle,
            style: const TextStyle(
              color: AppColors.textSecondary,
              fontSize: _sectionSubtitleFont,
            ),
          ),
        ],
      ],
    );
  }
}

String _sectionSubtitle(AppLocalizations l10n, String code) {
  return switch (code.toUpperCase()) {
    'DAILY' => l10n.rewardDailySectionSubtitle,
    'NEWBIE' => l10n.rewardNewbieSectionSubtitle,
    'INVITE' || 'INVITATION' => l10n.rewardInviteSectionSubtitle,
    _ => '',
  };
}

class _TaskGroupCard extends StatelessWidget {
  const _TaskGroupCard({
    super.key,
    required this.l10n,
    required this.rewards,
    required this.section,
    required this.onTaskAction,
  });

  final AppLocalizations l10n;
  final RewardController rewards;
  final RewardSection section;
  final Future<void> Function(RewardTask task) onTaskAction;

  @override
  Widget build(BuildContext context) {
    return Container(
      key: Key('reward-task-surface-${section.code}'),
      decoration: BoxDecoration(
        gradient: const LinearGradient(colors: [_taskCardStart, _taskCardEnd]),
        borderRadius: BorderRadius.circular(_taskCardRadius),
        border: Border.all(color: _taskCardBorder, width: _taskCardBorderWidth),
      ),
      child: Column(
        children: [
          for (var index = 0; index < section.tasks.length; index++) ...[
            _TaskRow(
              l10n: l10n,
              rewards: rewards,
              sectionCode: section.code,
              task: section.tasks[index],
              onTaskAction: onTaskAction,
            ),
            if (index < section.tasks.length - 1)
              const Divider(
                color: _divider,
                height: 1,
                indent: 16,
                endIndent: 16,
              ),
          ],
        ],
      ),
    );
  }
}

class _TaskRow extends StatelessWidget {
  const _TaskRow({
    required this.l10n,
    required this.rewards,
    required this.sectionCode,
    required this.task,
    required this.onTaskAction,
  });

  final AppLocalizations l10n;
  final RewardController rewards;
  final String sectionCode;
  final RewardTask task;
  final Future<void> Function(RewardTask task) onTaskAction;

  @override
  Widget build(BuildContext context) {
    return ConstrainedBox(
      constraints: const BoxConstraints(minHeight: _taskRowMinHeight),
      child: Padding(
        padding: const EdgeInsets.all(AppDimens.cardPadding),
        child: Row(
          crossAxisAlignment: CrossAxisAlignment.center,
          children: [
            RewardTaskLeading(task: task),
            const SizedBox(width: AppDimens.spaceMd),
            Expanded(child: _copy()),
            const SizedBox(width: AppDimens.spaceMd),
            _TaskButton(
              l10n: l10n,
              rewards: rewards,
              sectionCode: sectionCode,
              task: task,
              onTaskAction: onTaskAction,
            ),
          ],
        ),
      ),
    );
  }

  Widget _copy() {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      mainAxisAlignment: MainAxisAlignment.center,
      children: [
        Text(
          task.title,
          maxLines: 1,
          overflow: TextOverflow.ellipsis,
          style: const TextStyle(
            color: AppColors.textPrimary,
            fontSize: _taskTitleFont,
            fontWeight: FontWeight.w600,
          ),
        ),
        if (task.subtitle.isNotEmpty) ...[
          const SizedBox(height: AppDimens.spaceXs),
          Text(
            task.subtitle,
            maxLines: 1,
            overflow: TextOverflow.ellipsis,
            style: const TextStyle(
              color: AppColors.textSecondary,
              fontSize: _taskSubtitleFont,
            ),
          ),
        ],
        if (task.rewardCoin > 0) ...[
          const SizedBox(height: AppDimens.spaceXs),
          Row(
            mainAxisSize: MainAxisSize.min,
            children: [
              Text(
                '+${task.rewardCoin}',
                style: const TextStyle(
                  color: AppColors.brandRed,
                  fontSize: _taskRewardFont,
                  fontWeight: FontWeight.w700,
                ),
              ),
              const SizedBox(width: AppDimens.spaceXs),
              const RewardCoinIcon(size: 20),
            ],
          ),
        ],
      ],
    );
  }
}

class _TaskButton extends StatelessWidget {
  const _TaskButton({
    required this.l10n,
    required this.rewards,
    required this.sectionCode,
    required this.task,
    required this.onTaskAction,
  });

  final AppLocalizations l10n;
  final RewardController rewards;
  final String sectionCode;
  final RewardTask task;
  final Future<void> Function(RewardTask task) onTaskAction;

  @override
  Widget build(BuildContext context) {
    final loading = rewards.claimingTaskId == task.id;
    final dark = sectionCode.toUpperCase() == 'NEWBIE' && !task.claimable;
    final label = task.claimed
        ? l10n.rewardClaimed
        : task.claimable
        ? l10n.rewardClaimAction
        : (task.ctaText.isEmpty ? l10n.rewardGoAction : task.ctaText);
    return ConstrainedBox(
      key: Key('reward-task-action-${task.id}'),
      constraints: const BoxConstraints(
        minWidth: _taskButtonMinWidth,
        minHeight: _taskButtonHeight,
      ),
      child: FilledButton(
        onPressed: task.claimed || loading
            ? null
            : () => unawaited(onTaskAction(task)),
        style: FilledButton.styleFrom(
          backgroundColor: dark ? _mutedActionStart : AppColors.brandRed,
          disabledBackgroundColor: AppColors.contentChip,
          minimumSize: const Size(_taskButtonMinWidth, _taskButtonHeight),
          tapTargetSize: MaterialTapTargetSize.shrinkWrap,
          padding: const EdgeInsets.symmetric(horizontal: AppDimens.spaceSm),
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(AppDimens.pillRadius),
          ),
        ),
        child: loading
            ? const SizedBox.square(
                dimension: 16,
                child: CircularProgressIndicator(strokeWidth: 2),
              )
            : Text(label, style: const TextStyle(fontSize: _taskButtonFont)),
      ),
    );
  }
}

class _Empty extends StatelessWidget {
  const _Empty({required this.label});

  final String label;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: AppDimens.spaceXl),
      child: Center(
        child: Text(
          label,
          style: const TextStyle(color: AppColors.textTertiary),
        ),
      ),
    );
  }
}