'use client';

import { useState, useRef, useEffect } from 'react';
import {
  Box,
  TextField,
  IconButton,
  Paper,
  Typography,
  Avatar,
  CircularProgress,
  Chip,
} from '@mui/material';
import { Send, SmartToy, Person, AutoAwesome } from '@mui/icons-material';
import { motion, AnimatePresence } from 'framer-motion';
import { useAuth } from '@/lib/auth/AuthContext';
import apiClient from '@/lib/api/client';

interface Message {
  id: string;
  role: 'user' | 'assistant';
  content: string;
  timestamp: Date;
}

const suggestedQuestions = [
  'How much should my baby sleep at 3 months?',
  'What are normal feeding patterns?',
  'When should I introduce solid foods?',
  'Tips for better sleep routine',
];

export const AIChatInterface: React.FC = () => {
  const [messages, setMessages] = useState<Message[]>([]);
  const [input, setInput] = useState('');
  const [isLoading, setIsLoading] = useState(false);
  const messagesEndRef = useRef<HTMLDivElement>(null);
  const { user } = useAuth();

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

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

  const handleSend = async (message?: string) => {
    const messageText = message || input.trim();
    if (!messageText || isLoading) return;

    const userMessage: Message = {
      id: Date.now().toString(),
      role: 'user',
      content: messageText,
      timestamp: new Date(),
    };

    setMessages((prev) => [...prev, userMessage]);
    setInput('');
    setIsLoading(true);

    try {
      const response = await apiClient.post('/api/v1/ai/chat', {
        message: messageText,
        conversationId: null,
      });

      const assistantMessage: Message = {
        id: (Date.now() + 1).toString(),
        role: 'assistant',
        content: response.data.data.message,
        timestamp: new Date(),
      };

      setMessages((prev) => [...prev, assistantMessage]);
    } catch (error) {
      console.error('AI chat error:', error);
      const errorMessage: Message = {
        id: (Date.now() + 1).toString(),
        role: 'assistant',
        content: 'Sorry, I encountered an error. Please try again.',
        timestamp: new Date(),
      };
      setMessages((prev) => [...prev, errorMessage]);
    } finally {
      setIsLoading(false);
    }
  };

  const handleSuggestedQuestion = (question: string) => {
    handleSend(question);
  };

  return (
    <Box
      sx={{
        height: 'calc(100vh - 200px)',
        display: 'flex',
        flexDirection: 'column',
        background: 'linear-gradient(135deg, #FFF5F5 0%, #FFE4E1 100%)',
        borderRadius: 2,
        overflow: 'hidden',
      }}
    >
      {/* Header */}
      <Paper
        elevation={0}
        sx={{
          p: 2,
          borderRadius: 0,
          background: 'rgba(255, 255, 255, 0.95)',
          backdropFilter: 'blur(10px)',
          borderBottom: '1px solid',
          borderColor: 'divider',
        }}
      >
        <Box sx={{ display: 'flex', alignItems: 'center', gap: 2 }}>
          <Avatar sx={{ bgcolor: 'primary.main' }}>
            <SmartToy />
          </Avatar>
          <Box>
            <Typography variant="h6" fontWeight="600">
              AI Parenting Assistant
            </Typography>
            <Typography variant="caption" color="text.secondary">
              Ask me anything about parenting and childcare
            </Typography>
          </Box>
        </Box>
      </Paper>

      {/* Messages Container */}
      <Box
        sx={{
          flex: 1,
          overflowY: 'auto',
          p: 2,
          display: 'flex',
          flexDirection: 'column',
          gap: 2,
        }}
      >
        {messages.length === 0 && (
          <Box
            sx={{
              flex: 1,
              display: 'flex',
              flexDirection: 'column',
              alignItems: 'center',
              justifyContent: 'center',
              gap: 3,
            }}
          >
            <AutoAwesome sx={{ fontSize: 64, color: 'primary.main', opacity: 0.5 }} />
            <Typography variant="h6" color="text.secondary" textAlign="center">
              Hi {user?.name}! How can I help you today?
            </Typography>
            <Box
              sx={{
                display: 'flex',
                flexWrap: 'wrap',
                gap: 1,
                justifyContent: 'center',
                maxWidth: 600,
              }}
            >
              {suggestedQuestions.map((question, index) => (
                <Chip
                  key={index}
                  label={question}
                  onClick={() => handleSuggestedQuestion(question)}
                  sx={{
                    borderRadius: 3,
                    '&:hover': {
                      bgcolor: 'primary.light',
                      color: 'white',
                    },
                  }}
                />
              ))}
            </Box>
          </Box>
        )}

        <AnimatePresence>
          {messages.map((message) => (
            <motion.div
              key={message.id}
              initial={{ opacity: 0, y: 20 }}
              animate={{ opacity: 1, y: 0 }}
              exit={{ opacity: 0 }}
              transition={{ duration: 0.3 }}
            >
              <Box
                sx={{
                  display: 'flex',
                  gap: 2,
                  justifyContent: message.role === 'user' ? 'flex-end' : 'flex-start',
                }}
              >
                {message.role === 'assistant' && (
                  <Avatar sx={{ bgcolor: 'primary.main', mt: 1 }}>
                    <SmartToy />
                  </Avatar>
                )}
                <Paper
                  elevation={0}
                  sx={{
                    p: 2,
                    maxWidth: '70%',
                    borderRadius: 3,
                    bgcolor:
                      message.role === 'user'
                        ? 'primary.main'
                        : 'rgba(255, 255, 255, 0.95)',
                    color: message.role === 'user' ? 'white' : 'text.primary',
                    backdropFilter: 'blur(10px)',
                  }}
                >
                  <Typography variant="body1" sx={{ whiteSpace: 'pre-wrap' }}>
                    {message.content}
                  </Typography>
                  <Typography
                    variant="caption"
                    sx={{
                      mt: 1,
                      display: 'block',
                      opacity: 0.7,
                    }}
                  >
                    {message.timestamp.toLocaleTimeString()}
                  </Typography>
                </Paper>
                {message.role === 'user' && (
                  <Avatar sx={{ bgcolor: 'secondary.main', mt: 1 }}>
                    <Person />
                  </Avatar>
                )}
              </Box>
            </motion.div>
          ))}
        </AnimatePresence>

        {isLoading && (
          <Box sx={{ display: 'flex', gap: 2 }}>
            <Avatar sx={{ bgcolor: 'primary.main' }}>
              <SmartToy />
            </Avatar>
            <Paper
              elevation={0}
              sx={{
                p: 2,
                borderRadius: 3,
                bgcolor: 'rgba(255, 255, 255, 0.95)',
                display: 'flex',
                alignItems: 'center',
                gap: 1,
              }}
            >
              <CircularProgress size={20} />
              <Typography variant="body2" color="text.secondary">
                Thinking...
              </Typography>
            </Paper>
          </Box>
        )}

        <div ref={messagesEndRef} />
      </Box>

      {/* Input Area */}
      <Paper
        elevation={0}
        sx={{
          p: 2,
          borderRadius: 0,
          background: 'rgba(255, 255, 255, 0.95)',
          backdropFilter: 'blur(10px)',
          borderTop: '1px solid',
          borderColor: 'divider',
        }}
      >
        <Box sx={{ display: 'flex', gap: 1, alignItems: 'flex-end' }}>
          <TextField
            fullWidth
            multiline
            maxRows={4}
            placeholder="Ask me anything..."
            value={input}
            onChange={(e) => setInput(e.target.value)}
            onKeyPress={(e) => {
              if (e.key === 'Enter' && !e.shiftKey) {
                e.preventDefault();
                handleSend();
              }
            }}
            disabled={isLoading}
            sx={{
              '& .MuiOutlinedInput-root': {
                borderRadius: 3,
              },
            }}
          />
          <IconButton
            color="primary"
            onClick={() => handleSend()}
            disabled={!input.trim() || isLoading}
            sx={{
              width: 48,
              height: 48,
              bgcolor: 'primary.main',
              color: 'white',
              '&:hover': {
                bgcolor: 'primary.dark',
              },
              '&:disabled': {
                bgcolor: 'action.disabledBackground',
              },
            }}
          >
            <Send />
          </IconButton>
        </Box>
        <Typography variant="caption" color="text.secondary" sx={{ mt: 1, display: 'block' }}>
          This AI assistant provides general information. Always consult healthcare professionals
          for medical advice.
        </Typography>
      </Paper>
    </Box>
  );
};