#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <unistd.h>
#include <string.h>
#include <arpa/inet.h>
#include <errno.h>
#include <sys/stat.h>
#include <stdbool.h>
#include <assert.h>
#include <fcntl.h>
#include <time.h>
#include <pthread.h>
#include "socket_wrapper.h"
#include "timerhelper.h"

#ifndef DEFAULT_TIMEOUT
static const int TIMEOUT = 5;
#else
static const int TIMEOUT = DEFAULT_TIMEOUT;
#endif
#ifndef DEFAULT_PROGRESS_BAR_WIDTH
static const int PROGRESS_BAR_WIDTH = 30;
#else
static const int PROGRESS_BAR_WIDTH = DEFAULT_PROGRESS_BAR_WIDTH;
#endif

enum{
    FILENAME_BUF_SIZE = 1024
};
/*========
 *Operation
 *========*/
//if success, return zero
int sendReadOp(int sock,const char * filename){
    struct ReadOp op;
    op.file_url_size = strlen(filename);
    op.padding0 = 0;
    if(send(sock,&op,sizeof(op),0)<0){
        perror("readop send fail");
        return -1;
    }
    #ifdef MUL_CLIENT
    sleep(MUL_CLIENT);
    #endif
    if(send(sock,filename,op.file_url_size,0)<0){
        perror("readop filename send fail");
        return -1;
    }
    return 0;
}
/** 
 * @arg cur_progress : it is percentage.
*/
bool isProgressBarNeedUpdate(size_t offset,size_t total,double cur_progress){
    return ((double)offset / (double)total) > (cur_progress / 100.0);
}
void DisplayProgressBar(size_t offset,size_t total,double cur_progress){
    char buf[PROGRESS_BAR_WIDTH];
    size_t i;
    size_t cur_pos = (cur_progress / 100.0 * PROGRESS_BAR_WIDTH); //must be less than SIZE_MAX. other value is undefined behavior.
    for (i = 0; i < PROGRESS_BAR_WIDTH; i++)
    {
        if (i < cur_pos)
            buf[i] = '=';
        else if(i == cur_pos)
            buf[i] = '>';
        else buf[i] = '.';
    }
    printf("\r[%s]: %.2f%% bytes: %ld/%ld bytes",buf,cur_progress,total,offset);
}
void DisplayProgressBar100Percent(size_t total){
    size_t i;
    char buf[PROGRESS_BAR_WIDTH+1];
    for (i = 0; i < PROGRESS_BAR_WIDTH; i++){
        buf[i] = '=';
    }
    buf[PROGRESS_BAR_WIDTH] = '\0';
    printf("\r[%s]: 100%% bytes: %ld/%ld bytes\n",buf,total,total);
}
static bool DisplayProgress = true;
int recvFile(int sock, const char * filename,size_t file_size){
    int fd;
    size_t count = 0;
    int i;
    double cur_progress = 1;
    int return_value = 0;
    int buf_sz = getBufferSizeFrom(sock);
    uint8_t * buf = malloc(buf_sz*sizeof(*buf));
    if (buf == NULL){
        return -1;
    }
    fd = open(filename,O_WRONLY|O_CREAT|O_TRUNC,S_IRWXU|S_IRWXG|S_IROTH);
    if (fd < 0)
    {
        perror("file open fail");
        return -1;
    }
    
    while (file_size - count > 0)
    {
        int readed = buf_sz < file_size - count ? buf_sz : file_size - count;
        if((i = recv_until_byte(sock,buf,readed,TIMEOUT)) < 0){
            if(i == -2) 
                fprintf(stderr,"recv file failed : timeout connetion lost\n");
            else perror("recv file failed");
            return_value = -1;
            goto END;
        }
        if(write(fd,buf,readed)<0){
            perror("file write failed");
            return_value = -1;
            goto END;
        }
        if( DisplayProgress && isProgressBarNeedUpdate(count,file_size,cur_progress) ){
            DisplayProgressBar(count,file_size,cur_progress);
            cur_progress = (int)((((double)count / (double)file_size)) * 100.0 + 1.0);
            fflush(stdout);
        }
        count += readed;
        #ifdef SLOW_CLIENT
            usleep(SLOW_CLIENT);
        #endif
    }
    if(DisplayProgress)
        DisplayProgressBar100Percent(file_size);
END:
    free(buf);
    close(fd);
    return return_value;
}

int recvData(int sock,const char * filename){
    struct TransferResult res;
    int i=0;
    if((i=recv_until_byte(sock,&res,sizeof(res),TIMEOUT)) < 0){
        if (i == -2) fprintf(stderr,"timeout\n");
        else perror("recv fail");
        return -1;
    }
    char error_meesage_buf[80] = "";
    switch(res.res){
        case RES_ERR:
            fprintf(stderr,"Server Fail: %s\n", strerror(res.err_number));
            return -1;
        case RES_USR_ERR:
            assert(res.error_msg_size < 80);/*todo : fix*/
            if((i=recv_until_byte(sock,error_meesage_buf,res.error_msg_size,TIMEOUT)) < 0){
                if (i == -2) fprintf(stderr,"timeout\n");
                else perror("recv fail");
                return -1;
            }
            fprintf(stderr,"Error Message From Server: %s\n",error_meesage_buf);
            return -1;
        case RES_OK:
            return recvFile(sock,filename,res.file_size);
            break;
        default:
            fprintf(stderr,"unknown value!\n");
            return -1;
    }

    return 0;
}

static bool quiet_mode = false;
int SendOpAndReceiveFile(const char * filename, struct sockaddr const * addr){
    int sock;
    int ret = -1;
    if(!quiet_mode)
        fprintf(stdout,"request %s\n",filename);
        
    sock = socket(AF_INET,SOCK_STREAM,0);
    if(sock < 0){
        perror("sock create fail");
        return -1;
    }
    
    if(connect(sock,(struct sockaddr *)addr,sizeof(*addr)) < 0){
        perror("connect failed");
        return -1;
    }
    if(sendReadOp(sock,filename) == 0){
        ret = recvData(sock,filename);
    }
    close(sock);
    return ret;
}
//====
//bench
//====
struct benchmark_data{
    bool benchmode;
    struct timespec begin;
    struct timespec end;
    clockid_t clock_id;
    struct timespec resolution;
    int op_count;
} bench = {0,};

void init_bench_data(){
    int i;
    memset(&bench,0,sizeof(bench));
    bench.clock_id = CLOCK_PROCESS_CPUTIME_ID;
    i = clock_getres(bench.clock_id,&bench.resolution);
    if (i < 0){
        bench.clock_id = CLOCK_REALTIME;
        clock_getres(bench.clock_id,&bench.resolution);
    }
}
//====
//simple queue
//====
typedef enum{
    From_CharArray,
    From_FileStream
} queueing_method_t;

typedef struct SimpleCharQueue{
    queueing_method_t method;
    const char ** filename_begin;
    const char ** filename_end;
    FILE * fs;
} simple_queue_t;
//
// q have lifetime of arg b or arg e.
// do not deallocate before queue closed.
static bool init_queue_from_chararray(simple_queue_t * restrict q,const char ** b, const char ** e){
    q->method = From_CharArray;
    q->filename_begin = b;
    q->filename_end = e;
    return true;
}
//
// q have lifetime of arg f.
// do not close file f before queue closed.
static bool init_queue_from_file(simple_queue_t * restrict q, FILE * f){
    q->method = From_CharArray;
    q->fs = f;
    return true;
}

static const char * dequeue_from_simplecharqueue(simple_queue_t * restrict q,char * restrict buf, size_t size){
    const char * filename;
    if (q->method == From_CharArray){
        if (__glibc_unlikely(q->filename_begin == q->filename_end)) {
            return NULL;
        }
        filename = *(q->filename_begin++);
    }
    else{
        //unsafe.
        int t = fscanf(q->fs,"%s",buf);
        if (__glibc_unlikely(t != 1)) {
            return NULL;
        }
        filename = buf;
    }
    return filename;
}
//====
//thread
//====
struct SimpleThreadGlobal{
    size_t thread_arr_size;
    pthread_t * thread_arr;
    pthread_mutex_t queueing_mutex;
    simple_queue_t queue;
} global_state;
//if initialization is success, return true
bool init_global_state(struct SimpleThreadGlobal * t, size_t size){
    pthread_mutex_init(&t->queueing_mutex,NULL);
    t->thread_arr_size = size;
    t->thread_arr = (pthread_t *)malloc(sizeof(*global_state.thread_arr) * global_state.thread_arr_size);
    if (t->thread_arr == NULL){
        return false;
    }
    return true;
}

typedef struct SimpleThreadReturn{
    int retval;
    int op_count;
} worker_return_t;

__attribute_malloc__ worker_return_t * create_worker_return(){
    return (worker_return_t *)malloc(sizeof(worker_return_t));
}
void destroy_worker_return(worker_return_t * r){
    free(r);
}

typedef struct SimpleThreadArg{
    struct sockaddr addr;
} worker_arg_t;

__attribute_malloc__ worker_arg_t * create_thread_arg(struct sockaddr * r){
    worker_arg_t * ret = (worker_arg_t *)malloc(sizeof(*ret));
    memcpy(&ret->addr,r,sizeof(*r));
    return ret;
}
void destroy_thread_arg(worker_arg_t * arg){
    free(arg);
}

void * WorkerProc(void * args){
    worker_arg_t * arg = (worker_arg_t *)(args);
    worker_return_t * ret = create_worker_return();
    char filename_buf[FILENAME_BUF_SIZE];
    const char * filename;
    for(;;)
    {
        pthread_mutex_lock(&global_state.queueing_mutex);
        filename = dequeue_from_simplecharqueue(&global_state.queue,filename_buf,FILENAME_BUF_SIZE);
        pthread_mutex_unlock(&global_state.queueing_mutex);
        if(filename == NULL) break;
        ret->retval += SendOpAndReceiveFile(filename,&arg->addr);
        ret->op_count++;
    }
    destroy_thread_arg(arg);
    return ret;
}
//====
// cmd parse
//====
static struct {
    const char * server_name;
    in_port_t server_port;
    bool stdinisatty;
    int thread_number_option;
    bool quiet_mode;
} cmd_args = {
    .server_name = "",
    .server_port = 0
};

static const char * show_help_message(FILE * file,const char * argv0){
    static const char * msg = 
    "USAUE: %s SERVERNAME PORT [Option]... [FILENAME]...\n"
    "Options and arguments: \n"
    "-b or --benchmark\t:benchmark mode\n"
    "-nv or --no-verbose\t:no progress bar\n"
    "-h\t:print help message.\n";
    fprintf(file,msg,argv0);
    return msg;
}

static int parse_arg(int argc,const char *argv[]){
    int cur;
    cmd_args.stdinisatty = isatty(STDIN_FILENO);
    if (argc < (cmd_args.stdinisatty ? 4 : 3)){
        show_help_message(stderr,argv[0]);
        return 1;
    }
    cmd_args.server_name = argv[1];
    cmd_args.server_port = atoi(argv[2]);
    if (cmd_args.server_port == 0){
        fprintf(stderr,"port invalid\n");
        return -1;
    }
    cmd_args.quiet_mode = false;
    cmd_args.thread_number_option = 1;
    for(cur = 3;cur < argc; cur++){
        if (strcmp("-b",argv[cur])==0||strcmp("--benchmark",argv[cur])==0){
            bench.benchmode = true;
        }
        else if(strcmp("-nv",argv[cur]) == 0||strcmp("--no-verbose",argv[cur])==0){
            DisplayProgress = false;
        }
        else if(strcmp("-t",argv[cur]) == 0 || strcmp("--thread",argv[cur]) == 0){
            cur++;
            if (cur >= argc){
                fprintf(stderr,"need number");
                return -2;
            }
            cmd_args.thread_number_option = atoi(argv[cur]);
            if(cmd_args.thread_number_option == 0){
                fprintf(stderr,"not number or zero");
                return -2;
            }
        }
        else if(strcmp("-h",argv[cur]) == 0 || strcmp("--help",argv[cur]) == 0){
            show_help_message(stdout,argv[0]);
            return 0;
        }
        else if(strcmp("-q",argv[cur]) == 0 || strcmp("--quiet",argv[cur]) == 0){
            cmd_args.quiet_mode = true;
            quiet_mode = true;
        }
        else break;
    }
    if (cmd_args.stdinisatty){
        init_queue_from_chararray(&global_state.queue, &argv[cur],&argv[argc]);
    }
    else{
        init_queue_from_file(&global_state.queue,stdin);
    }
    return 0;
}

int main(int argc, const char *argv[]){
    struct sockaddr_in addr;
    const char * filename;
    int err;
    int retval = 0;

    init_bench_data();
    if(parse_arg(argc,argv) < 0) return EXIT_FAILURE;

    err = getsockaddrbyname(AF_INET,SOCK_STREAM,0,cmd_args.server_name,(struct sockaddr *)&addr);
    if (err != 0){
        int check;
        fprintf(stderr,"netdb fail: %s\n",gai_strerror(err));
        //assume that sernmae is *.*.*.* and try to parse addr
        check = inet_pton(AF_INET,cmd_args.server_name,&addr.sin_addr);
        assert(check != -1);
        if (check == 0){
            fprintf(stderr,"parsing fail : invaild format\n");
            return -1;
        }
    }
    addr.sin_family = AF_INET;
    addr.sin_port = htons(cmd_args.server_port);

    if (bench.benchmode){
        clock_gettime(bench.clock_id,&bench.begin);
    }
    if(cmd_args.thread_number_option == 1){
        char filename_buf[FILENAME_BUF_SIZE];
        for (;;){
            filename = dequeue_from_simplecharqueue(&global_state.queue,filename_buf,FILENAME_BUF_SIZE);
            if (filename == NULL) break;
            
            retval += SendOpAndReceiveFile(filename,(struct sockaddr *)&addr);
            bench.op_count++;
        }
    }
    else{
        int i = 0;
        init_global_state(&global_state,cmd_args.thread_number_option);
        for (i = 0; i < global_state.thread_arr_size; i++){
            worker_arg_t * arg = create_thread_arg((struct sockaddr *)&addr);
            pthread_create(&global_state.thread_arr[i],NULL,WorkerProc,arg);
        }
        for (i = 0; i < global_state.thread_arr_size; i++){
            worker_return_t * ret;
            pthread_join(global_state.thread_arr[i],(void **)&ret);
            bench.op_count += ret->op_count;
            retval += ret->retval;
            destroy_worker_return(ret);
        }
    }
    if (bench.benchmode){
        struct timespec result;
        double avg;
        clock_gettime(bench.clock_id,&bench.end);
        result = timespec_sub(bench.end,bench.begin);
        if (result.tv_sec == 0) avg = result.tv_nsec;
        else avg = result.tv_sec * 1e9 + result.tv_nsec;
        avg /= bench.op_count;
        fprintf(stdout,"operation: %lf us/op\n",avg / 1000.0);
        fprintf(stdout,"resolution: %ld sec %ld ns\n",bench.resolution.tv_sec,bench.resolution.tv_nsec);
    }
    
    return retval;
}