Prompt Composer

import 'package:flutter/material.dart';

class PromptComposer extends StatefulWidget {
  const PromptComposer({super.key});

  @override
  State<PromptComposer> createState() => _PromptComposerState();
}

class _PromptComposerState extends State<PromptComposer> {
  final _controller = TextEditingController();

  final _suggestions = const [
    'Summarize this article',
    'Write a product description',
    'Explain like I\'m five',
    'Draft a follow-up email',
  ];

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

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final scheme = theme.colorScheme;

    return Scaffold(
      appBar: AppBar(title: const Text('New prompt')),
      body: Column(
        children: [
          Expanded(
            child: ListView(
              padding: const EdgeInsets.all(16),
              children: [
                Text('Try one of these',
                    style: theme.textTheme.labelLarge
                        ?.copyWith(color: scheme.onSurfaceVariant)),
                const SizedBox(height: 12),
                Wrap(
                  spacing: 8,
                  runSpacing: 8,
                  children: [
                    for (final s in _suggestions)
                      ActionChip(
                        avatar: const Icon(Icons.auto_awesome, size: 16),
                        label: Text(s),
                        onPressed: () => _controller.text = s,
                      ),
                  ],
                ),
              ],
            ),
          ),
          SafeArea(
            top: false,
            child: Container(
              margin: const EdgeInsets.all(12),
              padding: const EdgeInsets.fromLTRB(12, 8, 8, 8),
              decoration: BoxDecoration(
                color: scheme.surfaceContainerHighest,
                borderRadius: BorderRadius.circular(24),
              ),
              child: Column(
                children: [
                  TextField(
                    controller: _controller,
                    maxLines: 5,
                    minLines: 1,
                    decoration: const InputDecoration(
                      hintText: 'Ask anything…',
                      border: InputBorder.none,
                      isCollapsed: true,
                    ),
                  ),
                  const SizedBox(height: 8),
                  Row(
                    children: [
                      IconButton(
                          tooltip: 'Add image',
                          onPressed: () => _showDemo(context, 'Add image (demo)'),
                          icon: const Icon(Icons.add_photo_alternate_outlined)),
                      IconButton(
                          tooltip: 'Attach file',
                          onPressed: () => _showDemo(context, 'Attach file (demo)'),
                          icon: const Icon(Icons.attach_file)),
                      IconButton(
                          tooltip: 'Voice input',
                          onPressed: () => _showDemo(context, 'Voice input (demo)'), icon: const Icon(Icons.mic_none)),
                      const Spacer(),
                      Container(
                        padding: const EdgeInsets.symmetric(
                            horizontal: 10, vertical: 4),
                        decoration: BoxDecoration(
                          border: Border.all(color: scheme.outlineVariant),
                          borderRadius: BorderRadius.circular(20),
                        ),
                        child: const Row(
                          mainAxisSize: MainAxisSize.min,
                          children: [
                            Text('GPT-4o'),
                            Icon(Icons.expand_more, size: 18),
                          ],
                        ),
                      ),
                      const SizedBox(width: 8),
                      IconButton.filled(
                          tooltip: 'Send prompt',
                          onPressed: () => _showDemo(context, 'Send prompt (demo)'),
                          icon: const Icon(Icons.arrow_upward)),
                    ],
                  ),
                ],
              ),
            ),
          ),
        ],
      ),
    );
  }
}

void _showDemo(BuildContext context, String message) {
  ScaffoldMessenger.of(context)
    ..hideCurrentSnackBar()
    ..showSnackBar(SnackBar(content: Text(message)));
}