FirstDigit.js

import React from 'react';
import { TextInput, StyleSheet, View, Text } from 'react-native';

/**
 * A 4-digit numeric input box for verification codes.
 * @param {Object} props
 * @param {string} props.value - Current code value.
 * @param {function} props.onChangeText - Callback to update value.
 */
const FirstDigit = ({ value, onChangeText }) => {
  const handleChange = (text) => {
    const cleanedText = text.replace(/[^0-9]/g, '');
    if (cleanedText.length <= 4) {
      onChangeText(cleanedText);
    }
  };

  return (
    <View style={styles.inputContainer}>
      <Text style={styles.label}>Enter 4-Digit Verification Code</Text>
      <TextInput
        style={styles.input}
        placeholder=" "
        value={value}
        onChangeText={handleChange}
        keyboardType="numeric"
        maxLength={4}
        autoCapitalize="none"
      />
    </View>
  );
};

const styles = StyleSheet.create({
  inputContainer: {
    marginVertical: 20,
    width: 300,
  },
  label: {
    fontSize: 16,
    marginBottom: 20,
    color: '#333',
    textAlign: 'left',
  },
  input: {
    height: 100,
    borderWidth: 5,
    borderRadius: 8,
    paddingHorizontal: 12,
    backgroundColor: '#fff',
    width: '100%',
    fontSize: 55,
    borderColor: 'black',
  },
});

export default FirstDigit;