package com.caimei.utils;


import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;

public class Digest {
    public static final String ENCODE = "UTF-8";

    public static String signMD5(String aValue, String encoding) {
        try {
            byte[] input = aValue.getBytes(encoding);
            MessageDigest md = MessageDigest.getInstance("MD5");
            return ConvertUtils.toHex(md.digest(input));
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
            return null;
        }
    }

    public static String hmacSign(String aValue) {
        try {
            byte[] input = aValue.getBytes();
            MessageDigest md = MessageDigest.getInstance("MD5");
            return ConvertUtils.toHex(md.digest(input));
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        }
    }

    public static String hmacSign(String aValue, String aKey) {
        return hmacSign(aValue, aKey, ENCODE);
    }

    public static String hmacSign(String aValue, String aKey, String encoding) {
        byte k_ipad[] = new byte[64];
        byte k_opad[] = new byte[64];
        byte keyb[];
        byte value[];
        try {
            keyb = aKey.getBytes(encoding);
            value = aValue.getBytes(encoding);
        } catch (UnsupportedEncodingException e) {
            keyb = aKey.getBytes();
            value = aValue.getBytes();
        }
        Arrays.fill(k_ipad, keyb.length, 64, (byte) 54);
        Arrays.fill(k_opad, keyb.length, 64, (byte) 92);
        for (int i = 0; i < keyb.length; i++) {
            k_ipad[i] = (byte) (keyb[i] ^ 0x36);
            k_opad[i] = (byte) (keyb[i] ^ 0x5c);
        }

        MessageDigest md = null;
        try {
            md = MessageDigest.getInstance("MD5");
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        }
        md.update(k_ipad);
        md.update(value);
        byte dg[] = md.digest();
        md.reset();
        md.update(k_opad);
        md.update(dg, 0, 16);
        dg = md.digest();
        return ConvertUtils.toHex(dg);
    }

    public static String hmacSHASign(String aValue, String aKey, String encoding) {
        byte k_ipad[] = new byte[64];
        byte k_opad[] = new byte[64];
        byte keyb[];
        byte value[];
        try {
            keyb = aKey.getBytes(encoding);
            value = aValue.getBytes(encoding);
        } catch (UnsupportedEncodingException e) {
            keyb = aKey.getBytes();
            value = aValue.getBytes();
        }
        Arrays.fill(k_ipad, keyb.length, 64, (byte) 54);
        Arrays.fill(k_opad, keyb.length, 64, (byte) 92);
        for (int i = 0; i < keyb.length; i++) {
            k_ipad[i] = (byte) (keyb[i] ^ 0x36);
            k_opad[i] = (byte) (keyb[i] ^ 0x5c);
        }

        MessageDigest md = null;
        try {
            md = MessageDigest.getInstance("SHA");
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        }
        md.update(k_ipad);
        md.update(value);
        byte dg[] = md.digest();
        md.reset();
        md.update(k_opad);
        md.update(dg, 0, 20);
        dg = md.digest();
        return ConvertUtils.toHex(dg);
    }

    public static String digest(String aValue) {
        return digest(aValue, ENCODE);

    }

    public static String digest(String aValue, String encoding) {
        aValue = aValue.trim();
        byte value[];
        try {
            value = aValue.getBytes(encoding);
        } catch (UnsupportedEncodingException e) {
            value = aValue.getBytes();
        }
        MessageDigest md = null;
        try {
            md = MessageDigest.getInstance("SHA");
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        }
        return ConvertUtils.toHex(md.digest(value));
    }


    public static String digest(String aValue, String alg, String encoding) {
        aValue = aValue.trim();
        byte value[];
        try {
            value = aValue.getBytes(encoding);
        } catch (UnsupportedEncodingException e) {
            value = aValue.getBytes();
        }
        MessageDigest md = null;
        try {
            md = MessageDigest.getInstance(alg);
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        }
        return ConvertUtils.toHex(md.digest(value));
    }

    public static String udpSign(String aValue) {
        try {
            byte[] input = aValue.getBytes("UTF-8");
            MessageDigest md = MessageDigest.getInstance("SHA1");
            return new String(Base64.encode(md.digest(input)), ENCODE);
        } catch (Exception e) {
            return null;
        }
    }

}