import 'package:flutter/material.dart';
import 'package:patbond_flutter/core/theme/app_theme.dart';
import 'package:patbond_flutter/data/demo_data.dart';
import 'package:patbond_flutter/models/models.dart';
import 'package:patbond_flutter/state/app_state.dart';
import 'package:patbond_flutter/widgets/common.dart';

enum CreationMode { image, video }

class CreatePage extends StatefulWidget {
  const CreatePage({
    required this.appState,
    required this.onPublished,
    super.key,
  });

  final AppState appState;
  final ValueChanged<PostModel> onPublished;

  @override
  State<CreatePage> createState() => _CreatePageState();
}

class _CreatePageState extends State<CreatePage> {
  final titleController = TextEditingController();
  final contentController = TextEditingController();
  CreationMode mode = CreationMode.image;
  CreationStyle selectedStyle = creationStyles.first;
  String selectedModel = 'Patbond-V1';
  String duration = '5 秒';
  String resolution = '1080P';
  bool upscaling = true;
  bool uploaded = false;
  bool uploading = false;
  bool generating = false;
  int generationStep = 0;
  String? resultUrl;
  List<String> tags = ['可爱修勾', 'AI宠物'];

  @override
  void dispose() {
    titleController.dispose();
    contentController.dispose();
    super.dispose();
  }

  Future<void> simulateUpload() async {
    setState(() => uploading = true);
    await Future<void>.delayed(const Duration(milliseconds: 700));
    if (!mounted) return;
    setState(() {
      uploading = false;
      uploaded = true;
      resultUrl = null;
    });
  }

  Future<void> generate() async {
    if (!uploaded) {
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(const SnackBar(content: Text('请先选择一张宠物照片')));
      return;
    }
    setState(() {
      generating = true;
      generationStep = 1;
    });
    for (var step = 2; step <= 4; step++) {
      await Future<void>.delayed(const Duration(milliseconds: 650));
      if (!mounted) return;
      setState(() => generationStep = step);
    }
    await Future<void>.delayed(const Duration(milliseconds: 500));
    if (!mounted) return;
    setState(() {
      generating = false;
      resultUrl = selectedStyle.image;
      titleController.text = mode == CreationMode.image
          ? '豆豆的${selectedStyle.title}冒险'
          : '豆豆的 AI 萌宠短片';
      contentController.text = '刚刚用 Patbond 创作了新作品，快来看看豆豆的新造型吧！✨';
    });
  }

  Future<void> addTag() async {
    final controller = TextEditingController();
    final value = await showDialog<String>(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('添加话题'),
        content: TextField(
          controller: controller,
          autofocus: true,
          decoration: const InputDecoration(hintText: '输入话题名称'),
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context),
            child: const Text('取消'),
          ),
          FilledButton(
            onPressed: () => Navigator.pop(context, controller.text.trim()),
            child: const Text('添加'),
          ),
        ],
      ),
    );
    controller.dispose();
    if (value == null || value.isEmpty || tags.contains(value)) return;
    setState(() => tags = [...tags, value]);
  }

  void publish() {
    if (resultUrl == null || titleController.text.trim().isEmpty) {
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(const SnackBar(content: Text('请先完成生成并填写标题')));
      return;
    }
    final post = PostModel(
      id: 'post_user_${DateTime.now().millisecondsSinceEpoch}',
      authorName: '萌宠新手（我）',
      authorAvatar: userAvatar,
      time: '刚刚',
      breedTag: 'AI创作',
      content:
          '${titleController.text.trim()}\n\n${contentController.text.trim()}',
      mainImage: resultUrl!,
      likes: 1,
      tags: [...tags, mode == CreationMode.image ? 'AI生图' : 'AI视频'],
      comments: const [],
      hasLiked: true,
    );
    widget.appState.publishPost(post);
    setState(() {
      uploaded = false;
      resultUrl = null;
      generationStep = 0;
      titleController.clear();
      contentController.clear();
    });
    widget.onPublished(post);
  }

  @override
  Widget build(BuildContext context) {
    return ListView(
      padding: const EdgeInsets.fromLTRB(16, 12, 16, 28),
      children: [
        SegmentedButton<CreationMode>(
          segments: const [
            ButtonSegment(
              value: CreationMode.image,
              icon: Icon(Icons.image_outlined),
              label: Text('AI 图片'),
            ),
            ButtonSegment(
              value: CreationMode.video,
              icon: Icon(Icons.movie_creation_outlined),
              label: Text('AI 视频'),
            ),
          ],
          selected: {mode},
          showSelectedIcon: false,
          onSelectionChanged: (value) => setState(() {
            mode = value.first;
            resultUrl = null;
          }),
        ),
        const SizedBox(height: 16),
        _UploadCard(
          uploaded: uploaded,
          uploading: uploading,
          imageUrl: widget.appState.pet.avatarUrl,
          onTap: simulateUpload,
          onRemove: () => setState(() {
            uploaded = false;
            resultUrl = null;
          }),
        ),
        const SizedBox(height: 16),
        SectionCard(
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Text('生成设置', style: Theme.of(context).textTheme.titleMedium),
              const SizedBox(height: 14),
              DropdownButtonFormField<String>(
                initialValue: selectedModel,
                decoration: const InputDecoration(labelText: '创作模型'),
                items: ['Patbond-V1', 'Pet-Art Pro', 'Cute Motion']
                    .map(
                      (model) =>
                          DropdownMenuItem(value: model, child: Text(model)),
                    )
                    .toList(),
                onChanged: (value) {
                  if (value != null) setState(() => selectedModel = value);
                },
              ),
              if (mode == CreationMode.video) ...[
                const SizedBox(height: 12),
                _ChoiceRow(
                  title: '视频时长',
                  values: const ['5 秒', '10 秒', '15 秒'],
                  selected: duration,
                  onChanged: (value) => setState(() => duration = value),
                ),
              ],
              const SizedBox(height: 12),
              _ChoiceRow(
                title: '分辨率',
                values: const ['720P', '1080P', '2K'],
                selected: resolution,
                onChanged: (value) => setState(() => resolution = value),
              ),
              SwitchListTile.adaptive(
                contentPadding: EdgeInsets.zero,
                title: const Text('高清增强'),
                subtitle: const Text('提升毛发与眼睛细节'),
                value: upscaling,
                onChanged: (value) => setState(() => upscaling = value),
              ),
            ],
          ),
        ),
        const SizedBox(height: 18),
        Text('热门风格', style: Theme.of(context).textTheme.titleLarge),
        const SizedBox(height: 10),
        SizedBox(
          height: 150,
          child: ListView.separated(
            scrollDirection: Axis.horizontal,
            itemCount: creationStyles.length,
            separatorBuilder: (_, _) => const SizedBox(width: 10),
            itemBuilder: (context, index) {
              final style = creationStyles[index];
              final selected = style.id == selectedStyle.id;
              return InkWell(
                onTap: () => setState(() {
                  selectedStyle = style;
                  resultUrl = null;
                }),
                borderRadius: BorderRadius.circular(20),
                child: Container(
                  width: 125,
                  decoration: BoxDecoration(
                    border: Border.all(
                      color: selected ? AppColors.primary : AppColors.border,
                      width: selected ? 2 : 1,
                    ),
                    borderRadius: BorderRadius.circular(20),
                  ),
                  child: Stack(
                    fit: StackFit.expand,
                    children: [
                      RemoteImage(
                        url: style.image,
                        borderRadius: BorderRadius.circular(18),
                      ),
                      DecoratedBox(
                        decoration: BoxDecoration(
                          borderRadius: BorderRadius.circular(18),
                          gradient: const LinearGradient(
                            begin: Alignment.topCenter,
                            end: Alignment.bottomCenter,
                            colors: [Colors.transparent, Color(0xCC0F172A)],
                          ),
                        ),
                      ),
                      Positioned(
                        left: 12,
                        right: 12,
                        bottom: 10,
                        child: Column(
                          crossAxisAlignment: CrossAxisAlignment.start,
                          children: [
                            Text(
                              style.title,
                              style: const TextStyle(
                                color: Colors.white,
                                fontWeight: FontWeight.w800,
                              ),
                            ),
                            Text(
                              style.subtitle,
                              style: const TextStyle(
                                color: Color(0xFFE2E8F0),
                                fontSize: 10,
                              ),
                            ),
                          ],
                        ),
                      ),
                    ],
                  ),
                ),
              );
            },
          ),
        ),
        const SizedBox(height: 18),
        if (generating) _GenerationProgress(step: generationStep),
        FilledButton.icon(
          style: FilledButton.styleFrom(
            minimumSize: const Size.fromHeight(52),
            backgroundColor: AppColors.ink,
          ),
          onPressed: generating ? null : generate,
          icon: generating
              ? const SizedBox.square(
                  dimension: 18,
                  child: CircularProgressIndicator(
                    strokeWidth: 2,
                    color: Colors.white,
                  ),
                )
              : const Icon(Icons.auto_awesome),
          label: Text(generating ? '正在生成…' : '开始生成'),
        ),
        if (resultUrl != null) ...[
          const SizedBox(height: 18),
          SectionCard(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Row(
                  children: [
                    const Icon(Icons.check_circle, color: AppColors.success),
                    const SizedBox(width: 8),
                    Text(
                      '生成完成',
                      style: Theme.of(context).textTheme.titleMedium,
                    ),
                  ],
                ),
                const SizedBox(height: 14),
                AspectRatio(
                  aspectRatio: 16 / 10,
                  child: RemoteImage(
                    url: resultUrl!,
                    borderRadius: BorderRadius.circular(18),
                  ),
                ),
                const SizedBox(height: 14),
                TextField(
                  controller: titleController,
                  decoration: const InputDecoration(labelText: '发布标题（必填）'),
                ),
                const SizedBox(height: 12),
                TextField(
                  controller: contentController,
                  maxLines: 3,
                  decoration: const InputDecoration(labelText: '分享正文'),
                ),
                const SizedBox(height: 12),
                Wrap(
                  spacing: 8,
                  runSpacing: 8,
                  children: [
                    ...tags.map(
                      (tag) => InputChip(
                        label: Text('#$tag'),
                        onDeleted: () => setState(
                          () =>
                              tags = tags.where((item) => item != tag).toList(),
                        ),
                      ),
                    ),
                    ActionChip(
                      avatar: const Icon(Icons.add, size: 16),
                      label: const Text('话题'),
                      onPressed: addTag,
                    ),
                  ],
                ),
                const SizedBox(height: 14),
                const ListTile(
                  contentPadding: EdgeInsets.zero,
                  leading: Icon(Icons.location_on_outlined),
                  title: Text('北京市 · 朝阳区'),
                  trailing: Icon(Icons.chevron_right),
                ),
                FilledButton.icon(
                  style: FilledButton.styleFrom(
                    minimumSize: const Size.fromHeight(48),
                  ),
                  onPressed: publish,
                  icon: const Icon(Icons.send_rounded),
                  label: const Text('发布到社区'),
                ),
              ],
            ),
          ),
        ],
      ],
    );
  }
}

class _UploadCard extends StatelessWidget {
  const _UploadCard({
    required this.uploaded,
    required this.uploading,
    required this.imageUrl,
    required this.onTap,
    required this.onRemove,
  });

  final bool uploaded;
  final bool uploading;
  final String imageUrl;
  final VoidCallback onTap;
  final VoidCallback onRemove;

  @override
  Widget build(BuildContext context) {
    return SectionCard(
      child: SizedBox(
        height: 190,
        width: double.infinity,
        child: uploading
            ? const Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  CircularProgressIndicator(),
                  SizedBox(height: 12),
                  Text('正在读取宠物照片…'),
                ],
              )
            : uploaded
            ? Stack(
                fit: StackFit.expand,
                children: [
                  RemoteImage(
                    url: imageUrl,
                    borderRadius: BorderRadius.circular(18),
                  ),
                  Positioned(
                    right: 8,
                    top: 8,
                    child: IconButton.filled(
                      tooltip: '移除照片',
                      onPressed: onRemove,
                      icon: const Icon(Icons.close),
                    ),
                  ),
                ],
              )
            : InkWell(
                onTap: onTap,
                borderRadius: BorderRadius.circular(18),
                child: const Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    CircleAvatar(
                      radius: 28,
                      child: Icon(Icons.add_photo_alternate_outlined),
                    ),
                    SizedBox(height: 12),
                    Text(
                      '选择宠物照片',
                      style: TextStyle(fontWeight: FontWeight.w800),
                    ),
                    SizedBox(height: 4),
                    Text('演示模式会读取豆豆的档案头像'),
                  ],
                ),
              ),
      ),
    );
  }
}

class _ChoiceRow extends StatelessWidget {
  const _ChoiceRow({
    required this.title,
    required this.values,
    required this.selected,
    required this.onChanged,
  });

  final String title;
  final List<String> values;
  final String selected;
  final ValueChanged<String> onChanged;

  @override
  Widget build(BuildContext context) {
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text(title, style: Theme.of(context).textTheme.bodySmall),
        const SizedBox(height: 7),
        Wrap(
          spacing: 8,
          children: values
              .map(
                (value) => ChoiceChip(
                  label: Text(value),
                  selected: value == selected,
                  onSelected: (_) => onChanged(value),
                ),
              )
              .toList(),
        ),
      ],
    );
  }
}

class _GenerationProgress extends StatelessWidget {
  const _GenerationProgress({required this.step});

  final int step;

  @override
  Widget build(BuildContext context) {
    const labels = ['分析宠物特征', '加载风格模型', '生成画面细节', '高清增强与合成'];
    return Padding(
      padding: const EdgeInsets.only(bottom: 14),
      child: SectionCard(
        child: Column(
          children: [
            LinearProgressIndicator(value: step / labels.length),
            const SizedBox(height: 12),
            for (var index = 0; index < labels.length; index++)
              ListTile(
                dense: true,
                contentPadding: EdgeInsets.zero,
                leading: Icon(
                  index < step ? Icons.check_circle : Icons.circle_outlined,
                  color: index < step ? AppColors.success : AppColors.muted,
                  size: 20,
                ),
                title: Text(labels[index]),
              ),
          ],
        ),
      ),
    );
  }
}