package cn.angs;

import java.io.*;
import java.util.Arrays;

/**
 * ClassName: FileInfoExecutor.java
 * Description:
 *
 * @author wangshun@cloudwalk.cn
 * @version 1.0.0
 * @date 2021/07/23 18:26
 */
public class FileInfoExecutor {

    private static final byte[] MPG_4 = new byte[]{0x66, 0x74, 0x79, 0x70, 0x4D, 0x53, 0x4E, 0x56};
    private static final byte[] MPG_4_V1 = new byte[]{0x66, 0x74, 0x79, 0x70, 0x69, 0x73, 0x6F, 0x6D};
    private static final byte[] AVI_HEAD = new byte[]{0x52, 0x49, 0x46, 0x46};
    private static final byte[] AVI_TAIL = new byte[]{0x41, 0x56, 0x49, 0x20, 0x4C, 0x49, 0x53, 0x54};

    public static boolean isMp4(String path) {
        byte[] read = read(path, 4, 11);
        return Arrays.equals(read, MPG_4) || Arrays.equals(read, MPG_4_V1);
    }

    public static boolean isAvi(String path) {
        byte[] head = read(path, 0, 3);
        if (Arrays.equals(head, AVI_HEAD)) {
            byte[] tail = read(path, 8, 15);
            return Arrays.equals(tail, AVI_TAIL);
        }
        return false;
    }

    private static byte[] read(String path, int from, int to) {
        byte[] result = new byte[to - from + 1];
        try {
            FileInputStream fis = new FileInputStream(path);
            BufferedInputStream bis = new BufferedInputStream(fis);
            bis.skip(from);
            bis.read(result, 0, to - from + 1);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }

    public static void main(String[] args) {
        System.out.println(isAvi("C:\\Users\\YCKJ2817\\Desktop\\测试\\1.avi"));
    }
}