#include <stdio.h>
#include <stdlib.h>
#include "client_socket.h"

using std::cout;
using std::cerr;
using std::endl;
using std::string;

void *downloadFile(void *args){
        ClientSocket dataSocket('T', 7071);

        char file_name_buf[256];
        int client_fd;

        string *ar = (string *) args;
        char args_local[1<<10];
        strcpy(args_local, ((*ar) + " 1").c_str()); //1 for download, 0 for upload
        sscanf(ar->c_str(), "%d %s", &client_fd, file_name_buf);
        delete(ar);

        cerr << "Requesting file: " << file_name_buf << endl;
        dataSocket.writeToSocket(args_local);


        FILE *fout = fopen(file_name_buf, "w");

        int bufSz=1<<20; //this MUST BE >= buffer size of the FTP server, so as not to cause buffer over flow, and drop data
        char packet[bufSz];
        memset(packet,0,bufSz);
        int n, total=0;

        while((n = dataSocket.readFromSocket(packet, bufSz))){
            total+=n;
            fwrite(packet, 1, n, fout);
        }

        fclose(fout);

        cerr << "total = " << 1.0*total/1000.0 << "Kbyte" << endl;
        cerr << "File successfully received, thank God :)" << endl;

        return NULL;
}

bool download_file_wrapper(ClientSocket *clientSocket, string fileName){
    char file_name_buf[1<<8];
    strcpy(file_name_buf, fileName.c_str());
    cerr << "Requesting file: " << file_name_buf << endl;
    clientSocket->writeToSocket(file_name_buf);

//========================================================
    char response[1<<8];
    clientSocket->readFromSocket(response, 1<<8);
    int client_fd;
    sscanf(response, "%d", &client_fd);

    if(client_fd < 0){
        if(client_fd==-1){
            cerr << "You have to wait until you current file transfer is finished" << endl;
        } else if(client_fd==-2){
            cerr << "Error! file not found" << endl;
        } else if(client_fd < -2){
            cerr << "Unexpected error has occurred, please try again later!" << endl;
        }

        return false;
    }

    string *arg = new string(string(response)+ " " + fileName);
    pthread_t thrd;
    pthread_create(&thrd, NULL, downloadFile, (void *) arg);

    return true;
}

bool uploadFile(){
    ClientSocket clientSocket('T', 7070);

    char file_name_buf[256] = "tureky.jpg";
    cerr << "Uploading file: " << file_name_buf << endl;
    clientSocket.writeToSocket(file_name_buf);

    FILE *fin = fopen(file_name_buf, "r");

    int bufSz=1<<20; //this MUST BE >= buffer size of the FTP server, so as not to cause buffer over flow, and drop data
    char packet[bufSz];
    memset(packet,0,bufSz);
    int n;

    if(!fin){
        cerr << "Error! couldn't open the file: " << file_name_buf << endl;
//      close(fd);
        return false;
    }

    while((n=fread(packet, 1, bufSz, fin))){
        clientSocket.writeToSocket(packet, n);
    }

    cerr << "closing file " << file_name_buf << endl;
    if(fclose(fin)==EOF){
        cerr << "Error! couldn't close the file: " << file_name_buf << endl;
        return false;
    }

    return true;
}

void upload_file_wrapper(ClientSocket *clientSocket, string fileName){

}

void go_ftp_client(){
    ClientSocket clientSocket('T', 7070);
    char input[1<<10];
    bool quit=false;

    while(!quit){
        printf("Select Action Number:\n---------------------\n1. Download File\n2. Upload File\n3. Quit\n");
        scanf("%s", input);
        int option;
        sscanf(input, "%d", &option);

        switch(option){
            case 1:
                printf("Enter file name:\n");
                scanf("%s", input);
                download_file_wrapper(&clientSocket, string(input));
                break;
            case 2:
                printf("Enter file name:\n");
                scanf("%s", input);
                upload_file_wrapper(&clientSocket, string(input));
                break;
            case 3:
                quit = true;
                break;
            case 4:
                printf("Invalid Option!");
                break;
        }

        printf("============================================\n\n");
    }
}

int main(){
//  downloadFile();
//  uploadFile();
    go_ftp_client();
    return 0;
}