//client

#include<stdio.h>
#include<string.h>
#include<sys/socket.h>
#include<arpa/inet.h>

#define DEFAULT_BUFLEN 512
#define DEFAULT_PORT   27015
#define MAX_FILES_NAME 40

int sock, read_size;
struct sockaddr_in server;
char server_reply[DEFAULT_BUFLEN];

void login();
void menu();
int sendFile();
int receiveFile();

char success[] = "success!", fail[] = "failure!";

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

    login();

	menu();

    close(sock);

    return 0;
}

void login(){
	char user[DEFAULT_BUFLEN], password[DEFAULT_BUFLEN];
	//Create socket
    sock = socket(AF_INET , SOCK_STREAM , 0);
    if (sock == -1)
    {
        printf("Could not create socket");
    }
    puts("Socket created");

    server.sin_addr.s_addr = inet_addr("127.0.0.1");
    server.sin_family = AF_INET;
    server.sin_port = htons( DEFAULT_PORT );

    //Connect to remote server
    if (connect(sock , (struct sockaddr *)&server , sizeof(server)) < 0)
    {
        perror("connect failed. Error");
        return;
    }

    puts("Connected\n");
    while(1)
    {
		memset(server_reply,0,strlen(server_reply));
        printf("Enter username : ");
        scanf("%s" , user);

        //slanje username-a serveru
        if( send(sock , user , strlen(user) , 0) < 0)
        {
            puts("Send failed");
            return;
        }

		printf("Enter password : ");
        scanf("%s" , password);

        //slanje password-a serveru
        if( send(sock , password , strlen(password) , 0) < 0)
        {
            puts("Send failed");
            return;
        }


        //prijem poruke od servera o uspesnosti prijavljivanja
        if( recv(sock , server_reply , DEFAULT_BUFLEN , 0) < 0)
        {
            puts("recv failed");
            break;
        }

        puts("Server reply :");
        puts(server_reply);

		if(strcmp(server_reply, "success!") == 0){
			return;
		}
    }
}

void menu(){
    char message[DEFAULT_BUFLEN], iterations[DEFAULT_BUFLEN];
	int ind=0, i, j;

	while(!ind){
		printf("\n1.upload\n2.download\n3.file list\n4.log off\n");
		printf("enter number: ");
		scanf("%s", message);
		if(message[1]!='\0'){
			printf("Enter one-digit number!\n");
			continue;
		}

		if( send(sock , message , DEFAULT_BUFLEN , 0) < 0)
        {
            puts("Send failed");
            return;
        }
		switch(message[0]){
			case '1':
				if(sendFile()==1)
					continue;
				break;
			case '2':
				if(receiveFile()==1)
                    continue;
				break;
			case '3':
				//prijem niza fajlova koji se trenutno nalaze na serveru
				if((recv(sock , iterations , DEFAULT_BUFLEN , 0)) < 0){
                    puts("recv failed");
                    return;
                }
                j=atoi(iterations);
				printf("Files on server: ");
				for(i=0;i<j;i++)
				{
				    if((recv(sock , server_reply , DEFAULT_BUFLEN , 0)) < 0){
                        puts("recv failed");
                        return;
                    }
					printf("%s", server_reply);
					memset(server_reply,0,strlen(server_reply));
					break;
				}

				printf("\n");
				break;
			case '4':
				//prilikom odjave klijenta, izlazi se i beskonacne petlje i server se gasi
				ind = 1;
				break;
			default:
				printf("Enter number between 1 and 4!\n");
		}
	}
	printf("Client disconnected!\n");
}

int sendFile(){
	char fileSize[DEFAULT_BUFLEN], filePath[DEFAULT_BUFLEN], chunk[1000], fileName[MAX_FILES_NAME];
	FILE *uploadFile;
	int size, i, n;
	printf("Enter file name: ");
	scanf("%s", fileName);
	if(send(sock,fileName,MAX_FILES_NAME,0) < 0)
	{
		puts("Send failed");
		return 1;
	}
	memset(filePath, 0, DEFAULT_BUFLEN);
	strcpy(filePath, "./clientFiles/");
	strcat(filePath, fileName);
	printf("%s\n", filePath);
	if((uploadFile = fopen(filePath, "rb"))==NULL){
		perror("Opening upload file failed!\n");
		if(send(sock,fail,DEFAULT_BUFLEN,0) < 0)
		{
			puts("Send failed");
			return 1;
		}
	}
	//klijent obavestava server da je uspelo otvaranje i a moze da pocne razmena
    if(send(sock,success,DEFAULT_BUFLEN,0) < 0)
	{
		puts("Send failed");
		return 1;
	}

	fseek(uploadFile, 0, SEEK_END);
	size = ftell(uploadFile);
	fseek(uploadFile, 0, SEEK_SET);
	n = size/1000;
	sprintf(fileSize, "%d", size);
	if(send(sock,fileSize,DEFAULT_BUFLEN,0) < 0)
	{
		puts("Send failed");
		return 1;
	}

	for(i = 0; i < n; i++){
		fread(chunk, sizeof(char), 1000, uploadFile);
		if(send(sock,chunk,1000,0) < 0)
		{
			puts("Send failed");
			return 1;
		}
	}
	fread(chunk,sizeof(char),size%1000,uploadFile);
	if(send(sock,chunk,1000,0) < 0)
	{
		puts("Send failed");
		return 1;
	}
	printf("Upload successful\n");

	if(!fclose(uploadFile)){
		printf("Closing upload file successful!\n");
	}else{
		printf("Closing upload file failed!\n");
		return 1;
	}

	return 0;
}

int receiveFile(){
    char fileOpen[DEFAULT_BUFLEN], fileName[MAX_FILES_NAME], filePath[DEFAULT_BUFLEN], buffer[1000], fileSize[DEFAULT_BUFLEN];
    int i, n;
    FILE *downloadFile;
	printf("Enter file name: ");
	scanf("%s", fileName);
	if(send(sock,fileName,MAX_FILES_NAME,0) < 0)
	{
		puts("Send failed");
		return 1;
	}

    if(recv(sock , fileOpen , DEFAULT_BUFLEN , 0) < 0){
        puts("recv failed");
        return 1;
    }
	//dobija informaciju od servera o uspesnosti otvaranja fajla
    if(strcmp(fileOpen, fail)==0){
		printf("Server could not open %s\n", fileName);
		return 1;
	}
	memset(filePath, 0, DEFAULT_BUFLEN);
	strcpy(filePath, "./clientFiles/");
    strcat(filePath, fileName);
    if((downloadFile = fopen(filePath, "wb"))==NULL){
        perror("Opening download file failed!\n");
        return 1;
    }

    if(recv(sock , fileSize , DEFAULT_BUFLEN , 0) < 0){
        puts("recv failed");
        return 1;
    }

    n = atoi(fileSize);
    for(i = 0; i<n/1000; i++){
        if(recv(sock , buffer , 1000 , 0) < 0){
            return 1;
        }
        fwrite(buffer, sizeof(char), 1000, downloadFile);
    }
    if(recv(sock , buffer , 1000 , 0) < 0){
        return 1;
    }
    fwrite(buffer, sizeof(char), n%1000, downloadFile);
	printf("Download successful!\n");
    if(!fclose(downloadFile)){
		printf("Closing downloaded file successful!\n");
	}else{
		printf("Closing downloaded file failed!\n");
		return 1;
	}


    return 0;
}