frontend/src/ChatInterface.tsx

import React, { useState, useEffect, useRef } from 'react';
import axios from 'axios';

interface ChatInterfaceProps {
    onCommand: (cmd: { task: string; type: '3d' | 'pcb' }) => void;
}

const ChatInterface: React.FC<ChatInterfaceProps> = ({ onCommand: _onCommand }) => {
    const [messages, setMessages] = useState([
        { role: 'assistant', content: 'Welcome to QuLab Infinite. I am ECH0, your R&D Navigator. What are we building today?' }
    ]);
    const [input, setInput] = useState('');
    const [isLoading, setIsLoading] = useState(false);
    const endRef = useRef<HTMLDivElement>(null);

    const scrollToBottom = () => {
        endRef.current?.scrollIntoView({ behavior: 'smooth' });
    };

    useEffect(() => {
        scrollToBottom();
    }, [messages]);

    const handleSend = async () => {
        if (!input.trim() || isLoading) return;

        const newMsg = { role: 'user', content: input };
        setMessages(prev => [...prev, newMsg]);
        setInput('');
        setIsLoading(true);

        try {
            const res = await axios.post('http://localhost:8000/chat', { message: newMsg.content });
            const data = res.data;
            const assistantMsg = { role: 'assistant', content: data.response };

            setMessages(prev => [...prev, assistantMsg]);

            if (data.action_result) {
                // If ECH0 performed a simulation, we can log it or show it.
                // For now, we print it as a system message.
                const sysMsg = {
                    role: 'system',
                    content: `[SIMULATION OUTPUT]: ${JSON.stringify(data.action_result.products)} produced. ${data.action_result.observations[0]}`
                };
                setMessages(prev => [...prev, sysMsg]);

                // If it was a PCB/3D task (legacy check), we could still trigger onCommand
                // But generally ECH0Service handles universal lab now.
                // We'll leave the prop just in case we want to force UI switches, 
                // but for now relying on the chat response is cleaner.
            }

        } catch (error) {
            console.error("Chat Error", error);
            setMessages(prev => [...prev, { role: 'assistant', content: "Communication Application Error. Is the backend or Ollama online?" }]);
        } finally {
            setIsLoading(false);
        }
    };

    const handleKeyDown = (e: React.KeyboardEvent) => {
        if (e.key === 'Enter') handleSend();
    };

    return (
        <div className="glass-panel" style={{
            width: '90%',
            maxWidth: '800px',
            height: '80vh',
            display: 'flex',
            flexDirection: 'column',
            overflow: 'hidden'
        }}>
            <div style={{
                padding: '1.5rem',
                background: 'rgba(0, 240, 255, 0.05)',
                borderBottom: '1px solid var(--glass-border)',
                display: 'flex',
                alignItems: 'center',
                gap: '1rem'
            }}>
                <div style={{
                    width: '40px', height: '40px', borderRadius: '50%',
                    background: 'var(--accent-cyan)',
                    boxShadow: '0 0 15px var(--accent-cyan)',
                    display: 'flex', alignItems: 'center', justifyContent: 'center',
                    fontWeight: 'bold', fontSize: '1.2rem', color: '#000'
                }}>
                    AI
                </div>
                <div>
                    <h2 style={{ fontSize: '1.2rem' }}>ECH0 COMMAND</h2>
                    <span style={{ fontSize: '0.8rem', color: isLoading ? 'var(--accent-purple)' : 'var(--accent-green)' }}>
                        ● {isLoading ? 'THINKING...' : 'ONLINE'}
                    </span>
                </div>
            </div>

            <div style={{ flexGrow: 1, padding: '1.5rem', overflowY: 'auto', display: 'flex', flexDirection: 'column', gap: '1.5rem' }}>
                {messages.map((msg, i) => (
                    <div key={i} style={{
                        display: 'flex',
                        justifyContent: msg.role === 'user' ? 'flex-end' : 'flex-start'
                    }}>
                        <div style={{
                            maxWidth: '70%',
                            padding: '1rem',
                            borderRadius: '12px',
                            background: msg.role === 'user' ? 'linear-gradient(135deg, var(--accent-purple), #8800ff)' : (msg.role === 'system' ? 'rgba(255,100,0,0.2)' : 'var(--bg-tertiary)'),
                            border: msg.role === 'assistant' ? '1px solid var(--glass-border)' : (msg.role === 'system' ? '1px dashed var(--accent-cyan)' : 'none'),
                            color: msg.role === 'system' ? 'var(--accent-cyan)' : 'white',
                            boxShadow: '0 4px 10px rgba(0,0,0,0.2)',
                            fontFamily: msg.role === 'system' ? 'var(--font-mono)' : 'inherit'
                        }}>
                            {msg.content}
                        </div>
                    </div>
                ))}
                <div ref={endRef} />
            </div>

            <div style={{ padding: '1.5rem', background: 'rgba(0,0,0,0.2)' }}>
                <div style={{
                    display: 'flex',
                    background: 'var(--bg-secondary)',
                    border: '1px solid var(--glass-border)',
                    borderRadius: '8px',
                    padding: '0.5rem'
                }}>
                    <input
                        type="text"
                        value={input}
                        onChange={(e) => setInput(e.target.value)}
                        onKeyDown={handleKeyDown}
                        placeholder="Type a command (e.g., 'Combine Sodium and Water')..."
                        disabled={isLoading}
                        style={{
                            flexGrow: 1,
                            background: 'transparent',
                            border: 'none',
                            color: 'white',
                            padding: '0.5rem',
                            outline: 'none',
                            fontFamily: 'var(--font-main)',
                            fontSize: '1rem',
                            opacity: isLoading ? 0.5 : 1
                        }}
                    />
                    <button onClick={handleSend} style={{ width: 'auto', padding: '0 1.5rem' }} disabled={isLoading}>SEND</button>
                </div>
            </div>
        </div>
    );
};


export default ChatInterface;