// src/components/Admin.js
import React, { useState, useEffect, useRef } from 'react';
import axios from 'axios';
import { Link, useNavigate } from 'react-router-dom';
import { PRIMARY_COLOR, SECONDARY_COLOR } from '../App';
import './Admin.css'; // Import the CSS file
import { 
    Typography, 
    Table, 
    TableBody, 
    TableCell, 
    TableContainer, 
    TableHead, 
    TableRow, 
    Paper, 
    Button, 
    Alert,
    Container,
    Box,
    TextField,
    Tab
  } from '@mui/material';


export default function Admin() {
  const [users, setUsers] = useState([]);
  const [username, setUsername] = useState('');
  const [email, setEmail] = useState('');
  const [password, setPassword] = useState('');
  const navigate = useNavigate();
  const fileInputRef = useRef(null);


  useEffect(() => {
    axios.get(`${process.env.REACT_APP_API_URL}/admin/user`, {
      headers: { Authorization: `Bearer ${localStorage.getItem('token')}` }
    })
    .then(response => {
      setUsers(response.data);
    })
    .catch(error => {
      console.error(error);
    });
  }, []);

  const fetchUsers = async () => {
    try {
      const response = await axios.get(`${process.env.REACT_APP_API_URL}/admin/user`, {
        headers: { Authorization: `Bearer ${localStorage.getItem('token')}` }
      });
      setUsers(response.data);
    } catch (error) {
      console.error('Error fetching users:', error);
      // Optionally, set an error message
      // setErrorMessage('Failed to fetch users. Please try again.');
    }
  };

  const handleCreateUser = async (e) => {
    e.preventDefault();
    try {
      const response = await axios.post(`${process.env.REACT_APP_API_URL}/admin/user`, {
        username,
        password,
        email
      }, {
        headers: { Authorization: `Bearer ${localStorage.getItem('token')}` }
      });
      setUsers([...users, response.data]);
      setUsername('');
      setPassword('');
      setEmail('');
    } catch (error) {
      console.error(error);
    }
  };

  const handleDeleteUser = async (id) => {
    try {
      await axios.delete(`${process.env.REACT_APP_API_URL}/admin/user/${id}`, {
        headers: { Authorization: `Bearer ${localStorage.getItem('token')}` }
      });
      setUsers(users.filter(user => user.id !== id));
      //setUsers(prevUsers => prevUsers.filter(user => user.id !== id));
      fetchUsers();

    } catch (error) {
      console.error(error);
    }
  };

  const handleBackupDatabase = async () => {
    try {
      const response = await axios.get(`${process.env.REACT_APP_API_URL}/admin/db`, {
        headers: { Authorization: `Bearer ${localStorage.getItem('token')}` },
        responseType: 'blob'
      });
      const blob = new Blob([response.data], { type: 'application/x-sqlite3' });
      const url = URL.createObjectURL(blob);
      const a = document.createElement('a');
      a.href = url;
      a.download = 'database.db';
      a.click();
    } catch (error) {
      console.error(error);
    }
  };

  const handleRestoreDatabase = async (e) => {
    e.preventDefault();
    try {
      const file = fileInputRef.current.files[0];
      const formData = new FormData();
      formData.append('database', file);
      console.log("sending request to restore db")
  
      const token = localStorage.getItem('token');
      if (!token) {
        throw new Error('No token found in local storage');
      }
  
      const response = await axios.post(`${process.env.REACT_APP_API_URL}/admin/db`, formData, {
        headers: { 
          Authorization: `Bearer ${token}`,
          'Content-Type': 'multipart/form-data'
        }
      });
  
      if (response.status === 200) {
        alert('Database restored successfully');
        navigate('/admin');
      } else {
        throw new Error(`Failed to restore database: ${response.statusText}`);
      }
    } catch (error) {
      console.error(error);
    }
  };

  return (
    <Container maxWidth="md">
      <Typography variant="h4" gutterBottom>
        Admin
      </Typography>
      
      <Box component="form" onSubmit={handleCreateUser} sx={{ mb: 4 }}>
        <Typography variant="h6" gutterBottom>
          Add New User
        </Typography>
        <TextField
          label="Username"
          variant="outlined"
          value={username}
          onChange={(e) => setUsername(e.target.value)}
          sx={{ mr: 2 }}
        />
        <TextField
          label="Password"
          type="password"
          variant="outlined"
          value={password}
          onChange={(e) => setPassword(e.target.value)}
          sx={{ mr: 2 }}
        />
        <TextField
          label="Email"
          variant="outlined"
          value={email}
          onChange={(e) => setEmail(e.target.value)}
          sx={{ mr: 2 }}
        />
        <Button type="submit" sx={{ backgroundColor: PRIMARY_COLOR, borderBottom: '1px solid', borderColor: '#444', color: SECONDARY_COLOR }} variant="contained" color="primary">
          Add User
        </Button>
      </Box>

      <TableContainer component={Paper}>
        <Table>
          <TableHead>
            <TableRow>
              <TableCell>ID</TableCell>
              <TableCell>Username</TableCell>
              <TableCell>Email</TableCell>
              <TableCell>Actions</TableCell>
            </TableRow>
          </TableHead>
          <TableBody>
            {users.map(user => (
              <TableRow key={user.ID}>
                <TableCell style={{ width: '30px' }}>{user.ID}</TableCell>
                <TableCell style={{ width: '100px'}}>{user.username}</TableCell>
                <TableCell style={{ width: '300px'}}>{user.email}</TableCell>
                <TableCell>
                  <Button 
                    variant="contained" 
                    color="error" 
                    onClick={() => handleDeleteUser(user.ID)}
                  >
                    Delete User
                  </Button>
                </TableCell>
              </TableRow>
            ))}
          </TableBody>
        </Table>
      </TableContainer>

      <Box sx={{ mt: 4 }}>
        <Button 
          variant="contained" 
          color="primary" 
          onClick={handleBackupDatabase}
          sx={{ mr: 2, backgroundColor: PRIMARY_COLOR, borderBottom: '1px solid', borderColor: '#444', color: SECONDARY_COLOR  }}
        >
          Backup Database
        </Button>

        <Button 
          variant="contained" 
          color="secondary" 
          component="label"
          sx={{ backgroundColor: PRIMARY_COLOR, borderBottom: '1px solid', borderColor: '#444', color: SECONDARY_COLOR }}
        >
          Restore Database
          <input
            type="file"
            hidden
            ref={fileInputRef}
            onChange={handleRestoreDatabase}
          />
        </Button>
      </Box>
    </Container>
  );
}