import React, { useState, useEffect, useLayoutEffect, useContext } from 'react';
import { useNavigate } from 'react-router-dom';
import { Grid, Card, CardContent, Typography, Box, CardMedia, IconButton, Snackbar, Alert } from '@mui/material';
import { UserContext } from '../contexts/UserContext';
import PersonAddIcon from '@mui/icons-material/PersonAdd';
import RemoveCircleOutlineIcon from '@mui/icons-material/RemoveCircleOutline';
import axios from 'axios';

import ConfirmDialog from './ConfirmDialog';

const Dashboard = () => {
  const { user, setUser } = useContext(UserContext);
  const [guilds, setGuilds] = useState([]);
  const [botStatus, setBotStatus] = useState({});
  const [snackbarOpen, setSnackbarOpen] = useState(false);
  const [snackbarMessage, setSnackbarMessage] = useState('');
  const [dialogOpen, setDialogOpen] = useState(false);
  const [selectedGuild, setSelectedGuild] = useState(null);
  const navigate = useNavigate();

  useEffect(() => {
    const urlParams = new URLSearchParams(window.location.search);
    const userParam = urlParams.get('user');
    const guildsParam = urlParams.get('guilds');

    if (userParam && guildsParam) {
      const parsedUser = JSON.parse(decodeURIComponent(userParam));
      const parsedGuilds = JSON.parse(decodeURIComponent(guildsParam));
      localStorage.setItem('user', JSON.stringify(parsedUser));
      localStorage.setItem('guilds', JSON.stringify(parsedGuilds));
      setUser(parsedUser);
      setGuilds(parsedGuilds);
      // Clean the URL
      window.history.replaceState({}, document.title, "/dashboard");
    } else {
      const storedUser = localStorage.getItem('user');
      const storedGuilds = localStorage.getItem('guilds');
      if (storedUser && storedGuilds) {
        setUser(JSON.parse(storedUser));
        setGuilds(JSON.parse(storedGuilds));
      }
    }
  }, [setUser]);

  useEffect(() => {
    const fetchBotStatus = async () => {
      const statusPromises = guilds.map(async (guild) => {
        try {
          const response = await axios.get(`http://localhost:3002/api/servers/${guild.id}/bot-status`);
          return { guildId: guild.id, isBotInServer: response.data.isBotInServer };
        } catch (error) {
          console.error(`Error fetching bot status for guild ${guild.id}:`, error);
          return { guildId: guild.id, isBotInServer: false };
        }
      });
      const results = await Promise.all(statusPromises);
      const newBotStatus = results.reduce((acc, curr) => {
        acc[curr.guildId] = curr.isBotInServer;
        return acc;
      }, {});
      setBotStatus(newBotStatus);
    };

    if (guilds.length > 0) {
      fetchBotStatus();
    }
  }, [guilds]);

  useLayoutEffect(() => {
    const scrollPosition = sessionStorage.getItem('scrollPosition');
    if (scrollPosition) {
      window.scrollTo(0, parseInt(scrollPosition));
      sessionStorage.removeItem('scrollPosition');
    }
  }, []);

  const handleCardClick = (guild) => {
    sessionStorage.setItem('scrollPosition', window.scrollY);
    navigate(`/server/${guild.id}`, { state: { guild } });
  };

  const handleInviteBot = async (e, guild) => {
    e.stopPropagation();
    const clientId = '1423377662055026840'; // Hardcoded client ID from user request
    const permissions = 8; // Administrator
    const inviteUrl = `https://discord.com/api/oauth2/authorize?client_id=${clientId}&permissions=${permissions}&scope=bot%20applications.commands&guild_id=${guild.id}&disable_guild_select=true`;
    window.open(inviteUrl, '_blank', 'noopener,noreferrer');
  };

  const handleLeaveBot = (e, guild) => {
    e.stopPropagation();
    setSelectedGuild(guild);
    setDialogOpen(true);
  };

  const handleConfirmLeave = async () => {
    if (!selectedGuild) return;
    try {
      await axios.post(`http://localhost:3002/api/servers/${selectedGuild.id}/leave`);
      setBotStatus(prevStatus => ({ ...prevStatus, [selectedGuild.id]: false }));
      setSnackbarMessage('Bot has left the server.');
      setSnackbarOpen(true);
    } catch (error) {
      console.error('Error leaving server:', error);
      setSnackbarMessage('Failed to make the bot leave the server.');
      setSnackbarOpen(true);
    }
    setDialogOpen(false);
    setSelectedGuild(null);
  };

  const handleSnackbarClose = (event, reason) => {
    if (reason === 'clickaway') {
      return;
    }
    setSnackbarOpen(false);
  };

  return (
    <div style={{ padding: '20px' }}>
      {/* UserSettings moved to NavBar */}
      <Typography variant="h4" gutterBottom>
        Dashboard
      </Typography>
      {user && (
        <Typography variant="h5" gutterBottom>
          Welcome, {user.username}
        </Typography>
      )}
      <Typography variant="h6" gutterBottom>
        Your Admin Servers:
      </Typography>
      <Grid container spacing={3}>
        {guilds.map(guild => (
          <Grid item xs={12} sm={6} md={4} lg={3} key={guild.id}>
            <Card 
              onClick={() => handleCardClick(guild)} 
              sx={{
                cursor: 'pointer',
                borderRadius: '20px',
                boxShadow: '0 8px 16px 0 rgba(0,0,0,0.2)',
                transition: 'transform 0.3s',
                height: '250px',
                display: 'flex',
                flexDirection: 'column',
                justifyContent: 'space-between',
                '&:hover': {
                  transform: 'scale(1.05)'
                }
              }}
            >
              <CardMedia
                component="img"
                sx={{ height: '60%', objectFit: 'cover' }}
                image={guild.icon ? `https://cdn.discordapp.com/icons/${guild.id}/${guild.icon}.png` : 'https://cdn.discordapp.com/embed/avatars/0.png'}
                alt={guild.name}
              />
              <CardContent>
                <Box sx={{ display: 'flex', alignItems: 'center', justifyContent: 'space-between', gap: 1, flexDirection: { xs: 'column', sm: 'row' } }}>
                  <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, width: '100%', justifyContent: { xs: 'center', sm: 'flex-start' } }}>
                    <Box
                      title={guild.name}
                      sx={{
                        px: 2,
                        py: 0.5,
                        borderRadius: '999px',
                        fontWeight: 'bold',
                        bgcolor: 'rgba(0,0,0,0.06)',
                        maxWidth: '100%',
                        overflow: 'hidden',
                        textOverflow: 'ellipsis',
                        whiteSpace: 'nowrap',
                        textAlign: { xs: 'center', sm: 'left' }
                      }}
                    >
                      {guild.name}
                    </Box>
                  </Box>
                  {botStatus[guild.id] ? (
                    <IconButton
                      aria-label={`Make bot leave ${guild.name}`}
                      size="small"
                      onClick={(e) => handleLeaveBot(e, guild)}
                    >
                      <RemoveCircleOutlineIcon />
                    </IconButton>
                  ) : (
                    <IconButton
                      aria-label={`Invite bot to ${guild.name}`}
                      size="small"
                      onClick={(e) => handleInviteBot(e, guild)}
                    >
                      <PersonAddIcon />
                    </IconButton>
                  )}
                </Box>
              </CardContent>
            </Card>
          </Grid>
        ))}
      </Grid>
      <Snackbar open={snackbarOpen} autoHideDuration={6000} onClose={handleSnackbarClose}>
        <Alert onClose={handleSnackbarClose} severity="info" sx={{ width: '100%' }}>
          {snackbarMessage}
        </Alert>
      </Snackbar>
      <ConfirmDialog
        open={dialogOpen}
        onClose={() => setDialogOpen(false)}
        onConfirm={handleConfirmLeave}
        title="Confirm Leave"
        message={`Are you sure you want the bot to leave ${selectedGuild?.name}?`}
      />
    </div>
  );
};

export default Dashboard;