#include <rpc/rpc.h>

#include <stdio.h>

#include <string.h>

#include "ftp.h"

extern __thread int errno;

/*

 * Gets the requested file from the server by calling the

 * remote procedure in a loop

 */

int get_file(char *host, char *name)

{

    CLIENT *clnt;

	int total_bytes = 0, write_bytes;

    readfile_res *result;

	request req;

	FILE *file;

    /*

	 * Initialize the request with the file name 

	 */

	req.name = name;

    /*

     * Create client handle used for calling FTPPROG on

     * the server designated on the command line. Use

     * the tcp protocol when contacting the server.

     */

    clnt = clnt_create(host, FTPPROG, FTPVER, "tcp");

    if (clnt == NULL) {

        /*

         * Couldn't establish connection with server.

         * Print error message and stop.

         */

         clnt_pcreateerror(host);

         exit(1);

    }

	/*

	 * Open the file for writing on the client machine

	 */

    file = fopen(name, "w");

    /*

     * Call the remote procedure retrieve_file on the server.

	 * During each iteration of the loop remote procedure is

	 * called and only 1024 bytes of data is read and returned

	 * by the server. The loop terminates when the data returned

	 * from the server is less than 1024 bytes

     */

	while (1) {

		/*

		 * Specifies the byte position where the next read should be

		 * started in the server.

		 */

		req.start = total_bytes;

        result = retrieve_file_1(&req, clnt);

        if (result == NULL) {

            /*

             * An RPC error occurred while calling the server.

             * Print error message and stop.

             */

            clnt_perror(clnt, host);

            exit(1);

        }

        /*

         * We successfully called the remote procedure.

         */

        if (result->errno != 0) {

            /*

             * A remote system error occurred.

             * Print error message and stop.

             */

            errno = result->errno;

            perror(name);

            exit(1);

        }

        /*

         * Successfully got a chunk of the file.

         * Write into our local file and update the

		 * total bytes of data read till now.

         */

		write_bytes = fwrite(result->readfile_res_u.chunk.data, 1, result->readfile_res_u.chunk.bytes, file);

		total_bytes += result->readfile_res_u.chunk.bytes;

		if (result->readfile_res_u.chunk.bytes < MAXLEN) 

		    break;

	}

	fclose(file);

	return 0;

}

/*

 * Stores the file on the server by calling the remote

 * procedure in a loop

 */

int put_file(char *host, char *name)

{

    CLIENT *clnt;

    char data[1024];

	int read_bytes;

    int *result;

	chunksend chunk;

	FILE *file;

    /*

     * Create client handle used for calling FTPPROG on

     * the server designated on the command line. Use

     * the tcp protocol when contacting the server.

     */

    clnt = clnt_create(host, FTPPROG, FTPVER, "tcp");

    if (clnt == NULL) {

        /*

         * Couldn't establish connection with server.

         * Print error message and stop.

         */

         clnt_pcreateerror(host);

         exit(1);

    }

    /*

	 * Open the file that should be stored on the server

	 */

    file = fopen(name, "r");

    /*

	 * Initialize the chunk to be sent with the name

	 * of the file

	 */ 

	chunk.name = name;

    /*

     * Call the remote procedure readdir on the server

	 * in a loop sending only 1024 bytes of data in each

	 * iteration. The loop terminates once the data less

	 * than 1024 bytes is sent.

     */

	while (1) {

		read_bytes = fread(data, 1, MAXLEN, file);

        chunk.data = data;

		chunk.bytes = read_bytes;

        result = send_file_1(&chunk, clnt);

        if (result == NULL) {

            /*

             * An RPC error occurred while calling the server.

             * Print error message and stop.

             */

            clnt_perror(clnt, host);

            exit(1);

        }

        /*

         * Okay, we successfully called the remote procedure.

         */

        if (*result != 0) {

            /*

             * A remote system error occurred.

             * Print error message and stop.

             */

            errno = *result;

            perror(name);

            exit(1);

        }

        /*

         * Successfully got a chunk of the file.

         * Write into our local file.

         */

		if (read_bytes < MAXLEN) 

		    break;

	}

	fclose(file);

	return 0;

}

/*

 * Handles commands read on the command line and calls

 * the appropriate function to handle the command

 */

int read_command(char *host)

{

	char command[MAXLEN];

	printf("> ");

	fflush(stdin);

	gets(command);

    if (strncmp(command, "get", 3) == 0) {

		return get_file(host, command+4);

	} else if(strncmp(command, "put", 3) == 0){

		return put_file(host, command+4);

	} else if(strncmp(command, "exit", 4) == 0){

		exit(0);

    } else {

		return -1;

	}

}

int main(int argc, char *argv[])

{

   int result;

   if (argc != 2) {

        fprintf(stderr, "usage: %s host\n", argv[0]);

        exit(1);

   }

   /*

    * Command handling loop

	*/

   while(TRUE) {

	   result = read_command(argv[1]);

   }

   return 0;

}