'use client'
import {
  Container,
  Grid,
  Card,
  CardContent,
  Typography,
  Box,
  TextField,
  Button,
  Paper,
  List,
  ListItem,
  Avatar,
  Chip,
  IconButton,
  Divider,
  useTheme,
  CircularProgress,
  Skeleton,
} from '@mui/material'
import {
  Chat,
  Send,
  Person,
  SmartToy,
  ContentCopy,
  ThumbUp,
  ThumbDown,
  Refresh,
} from '@mui/icons-material'
import { useState, useRef, useEffect } from 'react'
import { useTranslations, useLocale } from 'next-intl'

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

export default function ChatPage() {
  const theme = useTheme()
  const t = useTranslations('chat')
  const locale = useLocale()
  const [messages, setMessages] = useState<ChatMessage[]>([
    {
      id: '1',
      role: 'assistant',
      content: t('subtitle'),
      timestamp: new Date(),
    }
  ])
  const [inputMessage, setInputMessage] = useState('')
  const [isLoading, setIsLoading] = useState(false)
  const messagesEndRef = useRef<HTMLDivElement>(null)

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

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

  const handleSendMessage = async () => {
    if (!inputMessage.trim() || isLoading) return

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

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

    try {
      const response = await fetch('/api/chat', {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify({
          message: inputMessage,
          locale,
          history: messages.slice(-5).map(m => ({
            id: m.id,
            role: m.role,
            content: m.content,
            timestamp: m.timestamp.toISOString(),
          })),
        }),
      })

      if (!response.ok) {
        throw new Error('Failed to get response')
      }

      const data = await response.json()

      const assistantMessage: ChatMessage = {
        id: (Date.now() + 1).toString(),
        role: 'assistant',
        content: data.response || t('error') || 'Error',
        timestamp: new Date(),
      }

      setMessages(prev => [...prev, assistantMessage])
    } catch (error) {
      console.error('Error sending message:', error)
      const errorMessage: ChatMessage = {
        id: (Date.now() + 1).toString(),
        role: 'assistant',
        content: t('error') || 'Error',
        timestamp: new Date(),
      }
      setMessages(prev => [...prev, errorMessage])
    } finally {
      setIsLoading(false)
    }
  }

  const handleKeyPress = (event: React.KeyboardEvent) => {
    if (event.key === 'Enter' && !event.shiftKey) {
      event.preventDefault()
      handleSendMessage()
    }
  }

  const copyToClipboard = (text: string) => {
    navigator.clipboard.writeText(text)
  }

  const suggestedQuestions = [
    'Ce spune Biblia despre iubire?',
    'Explică-mi parabola semănătorului',
    'Care sunt fructele Duhului?',
    'Ce înseamnă să fii născut din nou?',
    'Cum pot să mă rog mai bine?',
  ]

  return (
    <Box>

      <Container maxWidth="lg" sx={{ py: 4 }}>
        {/* Header */}
        <Box sx={{ mb: 4, textAlign: 'center' }}>
          <Typography variant="h3" component="h1" gutterBottom>
            <Chat sx={{ fontSize: 40, mr: 2, verticalAlign: 'middle' }} />
            {t('title')}
          </Typography>
          <Typography variant="body1" color="text.secondary">
            {t('subtitle')}
          </Typography>
        </Box>

        <Grid container spacing={4}>
          {/* Suggested Questions Sidebar */}
          <Grid item xs={12} md={3}>
            <Card>
              <CardContent>
                <Typography variant="h6" gutterBottom>
                  {t('suggestions.title')}
                </Typography>
                <Typography variant="body2" color="text.secondary" sx={{ mb: 2 }}>
                  {t('suggestions.title')}
                </Typography>
                { (t.raw('suggestions.questions') as string[]).map((question, index) => (
                  <Chip
                    key={index}
                    label={question}
                    onClick={() => setInputMessage(question)}
                    sx={{
                      mb: 1,
                      mr: 1,
                      cursor: 'pointer',
                      '&:hover': {
                        bgcolor: 'primary.light',
                        color: 'white',
                      },
                    }}
                    variant="outlined"
                    size="small"
                  />
                ))}

                <Divider sx={{ my: 2 }} />

                {/* Tips section can be localized later via messages */}
              </CardContent>
            </Card>
          </Grid>

          {/* Main Chat Area */}
          <Grid item xs={12} md={9}>
            <Card sx={{ height: '70vh', display: 'flex', flexDirection: 'column' }}>
              {/* Chat Messages */}
              <Box sx={{ flexGrow: 1, overflow: 'auto', p: 2 }}>
                {messages.map((message) => (
                  <Box
                    key={message.id}
                    sx={{
                      display: 'flex',
                      justifyContent: message.role === 'user' ? 'flex-end' : 'flex-start',
                      mb: 2,
                    }}
                  >
                    <Box
                      sx={{
                        display: 'flex',
                        flexDirection: message.role === 'user' ? 'row-reverse' : 'row',
                        alignItems: 'flex-start',
                        maxWidth: '80%',
                      }}
                    >
                      <Avatar
                        sx={{
                          bgcolor: message.role === 'user' ? 'primary.main' : 'secondary.main',
                          mx: 1,
                        }}
                      >
                        {message.role === 'user' ? <Person /> : <SmartToy />}
                      </Avatar>

                      <Paper
                        elevation={1}
                        sx={{
                          p: 2,
                          bgcolor: message.role === 'user' ? 'primary.light' : 'background.paper',
                          color: message.role === 'user' ? 'white' : 'text.primary',
                          borderRadius: 2,
                        }}
                      >
                        <Typography variant="body1" sx={{ whiteSpace: 'pre-wrap' }}>
                          {message.content}
                        </Typography>

                        {message.role === 'assistant' && (
                          <Box sx={{ display: 'flex', gap: 1, mt: 1, justifyContent: 'flex-end' }}>
                            <IconButton
                              size="small"
                              onClick={() => copyToClipboard(message.content)}
                              title="Copiază răspunsul"
                            >
                              <ContentCopy fontSize="small" />
                            </IconButton>
                            <IconButton size="small" title="Răspuns util">
                              <ThumbUp fontSize="small" />
                            </IconButton>
                            <IconButton size="small" title="Răspuns neutil">
                              <ThumbDown fontSize="small" />
                            </IconButton>
                          </Box>
                        )}

                        <Typography
                          variant="caption"
                          sx={{
                            display: 'block',
                            textAlign: 'right',
                            mt: 1,
                            opacity: 0.7,
                          }}
                        >
                          {message.timestamp.toLocaleTimeString(locale === 'en' ? 'en-US' : 'ro-RO', {
                            hour: '2-digit',
                            minute: '2-digit',
                          })}
                        </Typography>
                      </Paper>
                    </Box>
                  </Box>
                ))}

                {isLoading && (
                  <Box sx={{ display: 'flex', justifyContent: 'flex-start', mb: 2 }}>
                    <Box sx={{ display: 'flex', alignItems: 'flex-start' }}>
                      <Avatar sx={{ bgcolor: 'secondary.main', mx: 1 }}>
                        <SmartToy />
                      </Avatar>
                      <Paper elevation={1} sx={{ p: 2, borderRadius: 2 }}>
                        <Box sx={{ display: 'flex', alignItems: 'center', gap: 1 }}>
                          <CircularProgress size={16} />
                          <Typography variant="body1">
                            {t('loading')}
                          </Typography>
                        </Box>
                      </Paper>
                    </Box>
                  </Box>
                )}

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

              {/* Message Input */}
              <Box sx={{ p: 2, borderTop: 1, borderColor: 'divider' }}>
                <Box sx={{ display: 'flex', gap: 1 }}>
                  <TextField
                    fullWidth
                    multiline
                    maxRows={4}
                    placeholder={t('placeholder')}
                    value={inputMessage}
                    onChange={(e) => setInputMessage(e.target.value)}
                    onKeyPress={handleKeyPress}
                    disabled={isLoading}
                    variant="outlined"
                  />
                  <Button
                    variant="contained"
                    onClick={handleSendMessage}
                    disabled={!inputMessage.trim() || isLoading}
                    sx={{ minWidth: 'auto', px: 2 }}
                  >
                    <Send />
                  </Button>
                </Box>

                <Typography variant="caption" color="text.secondary" sx={{ mt: 1, display: 'block' }}>
                  {t('enterToSend')}
                </Typography>
              </Box>
            </Card>
          </Grid>
        </Grid>
      </Container>
    </Box>
  )
}