import 'package:flutter/material.dart';
import 'package:liquid_glass_widgets/liquid_glass_widgets.dart';

class ChatMessage {
  final String text;
  final bool isMe;
  final String? avatar;

  ChatMessage({required this.text, required this.isMe, this.avatar});
}

class ChatPage extends StatefulWidget {
  final String contactName;
  final String avatarUrl;

  const ChatPage({
    super.key,
    required this.contactName,
    required this.avatarUrl,
  });

  @override
  State<ChatPage> createState() => _ChatPageState();
}

class _ChatPageState extends State<ChatPage> {
  final TextEditingController _controller = TextEditingController();
  final ScrollController _scrollController = ScrollController();

  late List<ChatMessage> _messages;

  @override
  void initState() {
    super.initState();

    _messages = [
      ChatMessage(text: '在吗？', isMe: false, avatar: widget.avatarUrl),
      ChatMessage(text: '在的，怎么啦 😊', isMe: true),
      ChatMessage(text: '今晚一起吃饭吗？', isMe: false, avatar: widget.avatarUrl),
    ];
  }

  void _sendMessage() {
    final text = _controller.text.trim();
    if (text.isEmpty) return;

    setState(() {
      _messages.add(ChatMessage(text: text, isMe: true));
    });

    _controller.clear();

    Future.delayed(const Duration(milliseconds: 100), () {
      _scrollController.animateTo(
        _scrollController.position.maxScrollExtent,
        duration: const Duration(milliseconds: 300),
        curve: Curves.easeOut,
      );
    });
  }

  Widget _buildAvatar(String? url) {
    return Padding(
      padding: const EdgeInsets.only(right: 8, top: 4),
      child: CircleAvatar(
        radius: 18,
        backgroundColor: Colors.grey[200],
        backgroundImage: url != null ? NetworkImage(url) : null,
        child:
            url == null
                ? const Icon(Icons.person, size: 18, color: Colors.grey)
                : null,
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: _buildAppBar(),
      body: SafeArea(
        child: Padding(
          padding: const EdgeInsets.all(10),
          child: Column(
            children: [
              Expanded(child: _buildMessage()),
              SizedBox(height: 10),
              _buildInput(),
            ],
          ),
        ),
      ),
    );
  }

  PreferredSizeWidget _buildAppBar() {
    return AppBar(
      backgroundColor: Color(0xFF120D25),
      foregroundColor: Colors.white,
      title: Text(
        widget.contactName,
        style: TextStyle(
          fontSize: 18,
          fontWeight: FontWeight.w600,
          color: Colors.white,
        ),
      ),
      centerTitle: true,
    );
  }

  Widget _buildMessage() {
    return GlassCard(
      child: ListView.separated(
        controller: _scrollController,
        separatorBuilder: (BuildContext context, int index) {
          return SizedBox(height: 10);
        },
        itemCount: _messages.length,
        itemBuilder: (context, index) {
          final msg = _messages[index];

          return Row(
            mainAxisAlignment:
                msg.isMe ? MainAxisAlignment.end : MainAxisAlignment.start,
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              if (!msg.isMe) _buildAvatar(msg.avatar),
              Flexible(
                child: GlassCard(
                  padding: const EdgeInsets.symmetric(
                    horizontal: 12,
                    vertical: 10,
                  ),
                  child: Text(
                    msg.text,
                    style: const TextStyle(fontSize: 16, color: Colors.white),
                  ),
                ),
              ),
              const SizedBox(width: 8),
              if (msg.isMe) _buildAvatar("https://picsum.photos/id/1027/200"),
            ],
          );
        },
      ),
    );
  }

  Widget _buildInput() {
    return SafeArea(
      child: GlassContainer(
        width: double.infinity,
        padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
        child: Row(
          children: [
            Expanded(
              child: TextField(
                controller: _controller,
                onSubmitted: (_) => _sendMessage(),
                style: const TextStyle(color: Colors.white),
                decoration: const InputDecoration(
                  hintText: '输入消息...',
                  hintStyle: TextStyle(color: Colors.white),
                  border: InputBorder.none,
                ),
              ),
            ),
            IconButton(
              onPressed: _sendMessage,
              icon: const Icon(Icons.send, color: Colors.green),
            ),
          ],
        ),
      ),
    );
  }
}