import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class Git {
//士大夫
    // 将任意进制字符串转换为十进制整数
    public static int toDecimal(String number, int base) {
        int decimal = 0;
        int power = 0;
        // 从字符串的末尾开始处理
        for (int i = number.length() - 1; i >= 0; i--) {
            char digit = number.charAt(i);

            // 如果是数字字符（0-9）
            if (Character.isDigit(digit)) {
                int value = Character.getNumericValue(digit);
                decimal += value * Math.pow(base, power);
            }
            // 如果是字母字符（A-F 或 a-f），表示10-15
            else if (Character.isLetter(digit)) {
                char upperDigit = Character.toUpperCase(digit);
                int value = upperDigit - 'A' + 10;
                decimal += value * Math.pow(base, power);
            } else {
                throw new IllegalArgumentException("Invalid character in number: " + digit);
            }

            power++;
        }

        return decimal;
    }

    // 将十进制整数转换为任意进制字符串
    public static String fromDecimal(int number, int base) {
        if (number == 0) {
            return "0";
        }

        StringBuilder result = new StringBuilder();
        char[] digits = "0123456789ABCDEF".toCharArray(); // 支持到16进制

        boolean isNegative = number < 0;
        if (isNegative) {
            number = -number;
        }

        while (number > 0) {
            int remainder = number % base;
            result.insert(0, digits[remainder]);
            number /= base;
        }

        if (isNegative) {
            result.insert(0, '-');
        }

        return result.toString();
    }

    public static void main(String[] args) {
        // 创建窗口
        JFrame frame = new JFrame("进制转换器");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(400, 300);
        frame.setLayout(new GridLayout(5, 2)); // 网格布局

        // 创建组件
        JLabel sourceBaseLabel = new JLabel("源进制（2-16）：");
        JTextField sourceBaseField = new JTextField();

        JLabel targetBaseLabel = new JLabel("目标进制（2-16）：");
        JTextField targetBaseField = new JTextField();

        JLabel numberLabel = new JLabel("要转换的数字：");
        JTextField numberField = new JTextField();

        JButton convertButton = new JButton("转换");
        JLabel resultLabel = new JLabel("转换结果：");

        // 添加组件到窗口
        frame.add(sourceBaseLabel);
        frame.add(sourceBaseField);
        frame.add(targetBaseLabel);
        frame.add(targetBaseField);
        frame.add(numberLabel);
        frame.add(numberField);
        frame.add(convertButton);
        frame.add(resultLabel);

        // 添加按钮事件处理
        convertButton.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                try {
                    int sourceBase = Integer.parseInt(sourceBaseField.getText().trim());
                    int targetBase = Integer.parseInt(targetBaseField.getText().trim());
                    String number = numberField.getText().trim();

                    // 验证源进制数字是否有效
                    for (char c : number.toCharArray()) {
                        if (!Character.isDigit(c) &&
                                !(Character.isLetter(c) && (Character.toUpperCase(c) >= 'A' && Character.toUpperCase(c) <= 'F') && sourceBase > 10)) {
                            throw new IllegalArgumentException("Invalid character in source base number: " + c);
                        }
                    }

                    // 将源进制数字转换为十进制
                    int decimalNumber = toDecimal(number, sourceBase);

                    // 将十进制数字转换为目标进制
                    String convertedNumber = fromDecimal(decimalNumber, targetBase);

                    // 显示结果
                    resultLabel.setText("转换后的" + targetBase + "进制数字是：" + convertedNumber);
                } catch (NumberFormatException | IllegalArgumentException ex) {
                    JOptionPane.showMessageDialog(frame, "错误: " + ex.getMessage(), "输入错误", JOptionPane.ERROR_MESSAGE);
                }
            }
        });

        // 显示窗口
        frame.setVisible(true);
    }
}