import 'dart:io';
import 'dart:math' as math;
import 'package:flutter/material.dart';
import 'package:carousel_slider/carousel_slider.dart';
import '../services/sake_recommendation_service.dart';
import '../screens/sake_detail_screen.dart';
import 'package:lucide_icons/lucide_icons.dart';

/// 3D風カルーセルウィジェット（推薦理由付き）
/// 円形配置で左右対称、奥行き感のあるローリングスライダー
/// 
/// v2.0: よりスムーズで3D的な奥行き表現に改善
class Sake3DCarouselWithReason extends StatefulWidget {
  final List<RecommendedSake> recommendations;
  final double height;

  const Sake3DCarouselWithReason({
    super.key,
    required this.recommendations,
    this.height = 260,
  });

  @override
  State<Sake3DCarouselWithReason> createState() => _Sake3DCarouselWithReasonState();
}

class _Sake3DCarouselWithReasonState extends State<Sake3DCarouselWithReason> {
  int _currentIndex = 0;
  final CarouselSliderController _carouselController = CarouselSliderController();

  @override
  Widget build(BuildContext context) {
    if (widget.recommendations.isEmpty) {
      return SizedBox(
        height: widget.height,
        child: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              Icon(LucideIcons.info, color: Colors.grey[400], size: 32),
              const SizedBox(height: 8),
              Text(
                '関連する日本酒を追加すると\nおすすめが表示されます',
                textAlign: TextAlign.center,
                style: TextStyle(color: Colors.grey[600], fontSize: 12),
              ),
            ],
          ),
        ),
      );
    }

    return Column(
      children: [
        SizedBox(
          height: widget.height - 30,
          child: CarouselSlider.builder(
            carouselController: _carouselController,
            itemCount: widget.recommendations.length,
            options: CarouselOptions(
              height: widget.height - 30,
              enlargeCenterPage: true,
              enlargeFactor: 0.35, // より強い拡大効果
              enlargeStrategy: CenterPageEnlargeStrategy.zoom, // ズーム戦略
              viewportFraction: 0.42, // 左右のカードをより見せる
              enableInfiniteScroll: widget.recommendations.length > 2,
              autoPlay: false,
              scrollPhysics: const BouncingScrollPhysics(), // よりスムーズなスクロール
              onPageChanged: (index, reason) {
                setState(() {
                  _currentIndex = index;
                });
              },
            ),
            itemBuilder: (context, index, realIndex) {
              final rec = widget.recommendations[index];
              // 奥行き計算
              final distance = (_currentIndex - index).abs();
              final depth = distance == 0 ? 1.0 : math.max(0.6, 1.0 - (distance * 0.2));
              
              return _buildCarouselCard(rec, index == _currentIndex, depth);
            },
          ),
        ),
        const SizedBox(height: 12),
        // スムーズなインジケーター
        _buildSmoothIndicator(),
      ],
    );
  }

  Widget _buildSmoothIndicator() {
    return Row(
      mainAxisAlignment: MainAxisAlignment.center,
      children: List.generate(
        widget.recommendations.length,
        (index) {
          final isActive = _currentIndex == index;
          return GestureDetector(
            onTap: () {
              _carouselController.animateToPage(index);
            },
            child: AnimatedContainer(
              duration: const Duration(milliseconds: 300),
              curve: Curves.easeOutCubic,
              width: isActive ? 20 : 8,
              height: 8,
              margin: const EdgeInsets.symmetric(horizontal: 3),
              decoration: BoxDecoration(
                borderRadius: BorderRadius.circular(4),
                color: isActive
                    ? Theme.of(context).colorScheme.secondary
                    : Colors.grey[400],
                boxShadow: isActive
                    ? [
                        BoxShadow(
                          color: Theme.of(context).colorScheme.secondary.withValues(alpha: 0.4),
                          blurRadius: 4,
                          spreadRadius: 1,
                        ),
                      ]
                    : null,
              ),
            ),
          );
        },
      ),
    );
  }

  Widget _buildCarouselCard(RecommendedSake rec, bool isCurrent, double depth) {
    return GestureDetector(
      onTap: () {
        Navigator.push(
          context,
          MaterialPageRoute(
            builder: (_) => SakeDetailScreen(sake: rec.item),
          ),
        );
      },
      child: AnimatedContainer(
        duration: const Duration(milliseconds: 400),
        curve: Curves.easeOutCubic, // よりスムーズなカーブ
        margin: EdgeInsets.symmetric(
          vertical: isCurrent ? 0 : 16 * (1 - depth + 0.4),
          horizontal: 6,
        ),
        // 3D変形効果（perspective + scale）
        transform: Matrix4.diagonal3Values(depth, depth, 1.0)
          ..setEntry(3, 2, 0.001), // パースペクティブ
        transformAlignment: Alignment.center,
        child: Card(
          elevation: isCurrent ? 16 : 4 * depth,
          shadowColor: Colors.black.withValues(alpha: 0.3),
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(isCurrent ? 20 : 16),
          ),
          clipBehavior: Clip.antiAliasWithSaveLayer,
          child: Stack(
            fit: StackFit.expand,
            children: [
              // 背景画像
              rec.item.displayData.imagePaths.isNotEmpty
                  ? Image.file(
                      File(rec.item.displayData.imagePaths.first),
                      fit: BoxFit.cover,
                    )
                  : Container(
                      color: Colors.grey[300],
                      child: Icon(
                        LucideIcons.image,
                        size: 50,
                        color: Colors.grey[600],
                      ),
                    ),

              // グラデーションオーバーレイ（より滑らか）
              Container(
                decoration: BoxDecoration(
                  gradient: LinearGradient(
                    begin: Alignment.topCenter,
                    end: Alignment.bottomCenter,
                    stops: const [0.3, 0.7, 1.0],
                    colors: [
                      Colors.transparent,
                      Colors.black.withValues(alpha: 0.3),
                      Colors.black.withValues(alpha: 0.85),
                    ],
                  ),
                ),
              ),

              // テキスト情報
              Positioned(
                bottom: 14,
                left: 10,
                right: 10,
                child: AnimatedOpacity(
                  duration: const Duration(milliseconds: 300),
                  opacity: isCurrent ? 1.0 : 0.7,
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.center,
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      Text(
                        rec.item.displayData.displayName,
                        maxLines: 2,
                        overflow: TextOverflow.ellipsis,
                        textAlign: TextAlign.center,
                        style: TextStyle(
                          color: Colors.white,
                          fontSize: isCurrent ? 15 : 13,
                          fontWeight: FontWeight.bold,
                          shadows: const [
                            Shadow(color: Colors.black, blurRadius: 6),
                          ],
                        ),
                      ),
                      const SizedBox(height: 4),
                      Text(
                        rec.item.displayData.displayPrefecture,
                        style: TextStyle(
                          color: Colors.white.withValues(alpha: 0.9),
                          fontSize: isCurrent ? 11 : 10,
                          shadows: const [
                            Shadow(color: Colors.black, blurRadius: 4),
                          ],
                        ),
                      ),
                      const SizedBox(height: 8),
                      // 推薦理由（中央カードのみ完全表示）
                      AnimatedContainer(
                        duration: const Duration(milliseconds: 300),
                        padding: EdgeInsets.symmetric(
                          horizontal: isCurrent ? 10 : 6,
                          vertical: isCurrent ? 5 : 3,
                        ),
                        decoration: BoxDecoration(
                          color: Theme.of(context).colorScheme.secondary.withValues(alpha: isCurrent ? 0.95 : 0.7),
                          borderRadius: BorderRadius.circular(6),
                          boxShadow: isCurrent
                              ? [
                                  BoxShadow(
                                    color: Theme.of(context).colorScheme.secondary.withValues(alpha: 0.3),
                                    blurRadius: 4,
                                    offset: const Offset(0, 2),
                                  ),
                                ]
                              : null,
                        ),
                        child: Text(
                          rec.reason,
                          style: TextStyle(
                            color: Colors.white,
                            fontSize: isCurrent ? 11 : 9,
                            fontWeight: FontWeight.w600,
                          ),
                          maxLines: isCurrent ? 2 : 1,
                          overflow: TextOverflow.ellipsis,
                          textAlign: TextAlign.center,
                        ),
                      ),
                    ],
                  ),
                ),
              ),

              // 中央のカードにグロー効果
              if (isCurrent)
                Positioned(
                  top: 0,
                  left: 0,
                  right: 0,
                  height: 3,
                  child: Container(
                    decoration: BoxDecoration(
                      gradient: LinearGradient(
                        colors: [
                          Colors.transparent,
                          Theme.of(context).colorScheme.secondary.withValues(alpha: 0.8),
                          Colors.transparent,
                        ],
                      ),
                    ),
                  ),
                ),
            ],
          ),
        ),
      ),
    );
  }
}