package com.qcloud.cos.demo;

import org.apache.commons.io.IOUtils;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileChecksum;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;

import java.io.IOException;
import java.net.URI;
import java.nio.ByteBuffer;

public class Demo {
            private static FileSystem initFS() throws IOException {
                Configuration conf = new Configuration();
               // For more information on the configuration items, visit https://www.tencentcloud.com/document/product/436/6884?from_cn_redirect=1#.E4.B8.8B.E8.BD.BD.E4.B8.8E.E5.AE.89.E8.A3.85.
               // The following configuration items are required

               conf.set("fs.cosn.impl", "org.apache.hadoop.fs.CosFileSystem");
               conf.set("fs.AbstractFileSystem.cosn.impl", "org.apache.hadoop.fs.CosN");
               conf.set("fs.cosn.userinfo.secretId", "xxxxxx");
               conf.set("fs.cosn.userinfo.secretKey", "xxxxxx");
               conf.set("fs.cosn.bucket.region", "xxxxxx");
               conf.set("fs.cosn.tmp.dir", "/data/chdfs_tmp_cache");

               // For more information on the configuration items, visit https://www.tencentcloud.com/document/product/436/71550?from_cn_redirect=1.
               // Required configuration items for the POSIX access mode (recommended)
               conf.set("fs.cosn.trsf.fs.AbstractFileSystem.ofs.impl", "com.qcloud.chdfs.fs.CHDFSDelegateFSAdapter");
               conf.set("fs.cosn.trsf.fs.ofs.impl", "com.qcloud.chdfs.fs.CHDFSHadoopFileSystemAdapter");
               conf.set("fs.cosn.trsf.fs.ofs.tmp.cache.dir", "com.qcloud.chdfs.fs.CHDFSHadoopFileSystemAdapter");
               conf.set("fs.cosn.trsf.fs.ofs.impl", "com.qcloud.chdfs.fs.CHDFSHadoopFileSystemAdapter");
               conf.set("fs.cosn.trsf.fs.ofs.tmp.cache.dir", "/data/chdfs_tmp_cache");

               // Replace `appid` with your actual `appid`
               conf.set("fs.cosn.trsf.fs.ofs.user.appid", "1250000000");
               // Replace `region` with your actual region
               conf.set("fs.cosn.trsf.fs.ofs.bucket.region", "ap-beijing");
               // For more information on the optional configuration items, visit https://www.tencentcloud.com/document/product/436/6884?from_cn_redirect=1#.E4.B8.8B.E8.BD.BD.E4.B8.8E.E5.AE.89.E8.A3.85.
               // Whether to enable CRC-64 checksum. It is disabled by default, meaning that you can't run the `hadoop fs -checksum` command to obtain the CRC-64 checksum of a file.
               conf.set("fs.cosn.crc64.checksum.enabled", "true");
               String cosHadoopFSUrl = "cosn://examplebucket-12500000000/";
               return FileSystem.get(URI.create(cosHadoopFSUrl), conf);
            }

        private static void mkdir(FileSystem fs, Path filePath) throws IOException {
                fs.mkdirs(filePath);
            }

        private static void createFile(FileSystem fs, Path filePath) throws IOException {
                // Create a file (if it already exists, it will be overwritten)
                // if the parent dir does not exist, fs will create it!
                FSDataOutputStream out = fs.create(filePath, true);
                try {
                        // Write a file
                        String content = "test write file";
                        out.write(content.getBytes());
                } finally {
                        // If `close` is returned successfully, the data write has succeeded. If an exception is thrown, the data write has failed.
                        out.close();
                }
            }

        private static void readFile(FileSystem fs, Path filePath) throws IOException {
                FSDataInputStream in = fs.open(filePath);
                try {
                        byte[] buf = new byte[4096];
                        int readLen = -1;
                        do {
                                readLen = in.read(buf);
                        } while (readLen >= 0);
                } finally {
                        IOUtils.closeQuietly(in);
                }
            }


            private static void queryFileOrDirStatus(FileSystem fs, Path path) throws IOException {
                FileStatus fileStatus = fs.getFileStatus(path);
                if (fileStatus.isDirectory()) {
                        System.out.printf("path %s is dir\\n", path);
                        return;
                }

            long fileLen = fileStatus.getLen();
                long accessTime = fileStatus.getAccessTime();
                long modifyTime = fileStatus.getModificationTime();
                String owner = fileStatus.getOwner();
                String group = fileStatus.getGroup();


                System.out.printf("path %s is file, fileLen: %d, accessTime: %d, modifyTime: %d, owner: %s, group: %s\\n",
                        path, fileLen, accessTime, modifyTime, owner, group);
            }


            // The default verification type is `COMPOSITE-CRC32C`
            private static void getFileCheckSum(FileSystem fs, Path path) throws IOException {
                FileChecksum checksum = fs.getFileChecksum(path);
                System.out.printf("path %s, checkSumType: %s, checkSumCrcVal: %d\\n",
                        path, checksum.getAlgorithmName(), ByteBuffer.wrap(checksum.getBytes()).getInt());
            }


            private static void copyFileFromLocal(FileSystem fs, Path chdfsPath, Path localPath) throws  IOException {
                fs.copyFromLocalFile(localPath, chdfsPath);
            }


            private static void copyFileToLocal(FileSystem fs, Path chdfsPath, Path localPath) throws  IOException {
                fs.copyToLocalFile(chdfsPath, localPath);
            }


            private static void renamePath(FileSystem fs, Path oldPath, Path newPath) throws IOException {
                fs.rename(oldPath, newPath);
            }


            private static void listDirPath(FileSystem fs, Path dirPath) throws IOException {
                FileStatus[] dirMemberArray = fs.listStatus(dirPath);


                for (FileStatus dirMember : dirMemberArray) {
                        System.out.printf("dirMember path %s, fileLen: %d\\n", dirMember.getPath(), dirMember.getLen());
                }
            }


            // The recursive deletion flag is used to delete directories
            // If recursion is `false` and `dir` is not empty, the operation will fail
            private static void deleteFileOrDir(FileSystem fs, Path path, boolean recursive) throws IOException {
                fs.delete(path, recursive);
            }


            private static void closeFileSystem(FileSystem fs) throws IOException {
                fs.close();
            }


            public static void main(String[] args) throws IOException {
                // Initialize the file system
                FileSystem fs = initFS();


                // Create a file
                Path chdfsFilePath = new Path("/folder/exampleobject.txt");
                createFile(fs, chdfsFilePath);


                // Read a file
                readFile(fs, chdfsFilePath);


                // Query a file or directory
                queryFileOrDirStatus(fs, chdfsFilePath);


                // Get a file checksum
                getFileCheckSum(fs, chdfsFilePath);


                // Copy a file from the local system
                Path localFilePath = new Path("file:///home/hadoop/cosn_demo/data/exampleobject.txt");
                copyFileFromLocal(fs, chdfsFilePath, localFilePath);


                // Download a file to the local file system
                Path localDownFilePath = new Path("file:///home/hadoop/cosn_demo/data/exampleobject.txt");
                copyFileToLocal(fs, chdfsFilePath, localDownFilePath);


                // Rename
                Path newPath = new Path("/doc/example.txt");
                renamePath(fs, chdfsFilePath, newPath);


                // Delete a file
                deleteFileOrDir(fs, newPath, false);


                // Create a directory
                Path dirPath = new Path("/folder");
                mkdir(fs, dirPath);


                // Create a file in a directory
                Path subFilePath = new Path("/folder/exampleobject.txt");
                createFile(fs, subFilePath);


                // List directories
                listDirPath(fs, dirPath);


                // Delete a directory
                deleteFileOrDir(fs, dirPath, true);


                // Close a file system
                closeFileSystem(fs);
            }
}