import "package:flutter/widgets.dart";
import "package:provider/provider.dart";

import "../providers/chat_provider.dart";
import "message_bubble.dart";

class ChatView extends StatefulWidget {
  const ChatView();

  @override
  State<ChatView> createState() => _ChatViewState();
}

class _ChatViewState extends State<ChatView> {
  late ScrollController _scrollController;

  @override
  void initState() {
    super.initState();
    _scrollController = ScrollController();
  }

  @override
  void dispose() {
    _scrollController.dispose();
    super.dispose();
  }

  void _scrollToBottom() {
    WidgetsBinding.instance.addPostFrameCallback((_) {
      if (_scrollController.hasClients) {
        _scrollController.animateTo(
          _scrollController.position.maxScrollExtent,
          duration: const Duration(milliseconds: 300),
          curve: Curves.easeOut,
        );
      }
    });
  }

  @override
  Widget build(BuildContext context) {
    return Consumer<ChatProvider>(
      builder: (context, chatProvider, _) {
        // scroll to bottom when new messages arrive
        if (chatProvider.messages.isNotEmpty) {
          _scrollToBottom();
        }

        return ListView.builder(
          controller: _scrollController,
          itemCount: chatProvider.messages.length,
          itemBuilder: (context, index) {
            final message = chatProvider.messages[index];
            return MessageBubble(message: message);
          },
        );
      },
    );
  }
}