#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#define BIN_FILENAME "bin.dat"

typedef struct{
    char tax_registry_number[14];
    char name[41];
    float earnings[5];
    char date_of_registration[11];
    struct Firm* next;
}Firm;
Firm* head = NULL;

//PROTOTYPNING
//primary functions
void add_new_firm();
void update_firm();
void show_information_for_firm_by_tax_registration_number();
void show_info_for_firms_in_interval();
//end primary functions

//secondary functions
void save_a_firm_into_a_text_file_by_address(Firm* address);
char* get_date(const char* type_of_date);
void input_info_on_address(Firm* address);
void print_info_by_address(Firm* address);
void free_list();
void reconstruct_list();
void read_list_from_bin_file(char* filename);
void save_list_to_bin_file(const char* filename);
int get_size();
void save_all_firms_into_text_files();
char* add_txt_at_the_end_of_the_file(char* filename);
int get_current_year();
int check_format_of_date(char* year);
char* get_reversed_date(char* date);
int menu();
//end secondary functions

//END PROTOTYPING

char* get_reversed_date(char* date){
    char* reversed_date = (char*)malloc(sizeof(11));
    reversed_date[0] = date[0];
    reversed_date[1] = date[1];
    reversed_date[2] = date[2];
    reversed_date[3] = date[3];
    reversed_date[8] = date[5];
    reversed_date[9] = date[6];
    reversed_date[5] = date[8];
    reversed_date[6] = date[9];
    reversed_date[4] = '.';
    reversed_date[7] = '.';
    reversed_date[10] = '\0';
    //printf("date: %s\n",date);
    //printf("reversed date: %s\n",reversed_date);

    return reversed_date;
}

int get_current_year(){
    time_t now;
    if ( time(&now) != (time_t)(-1) )
    {
      struct tm *mytime = localtime(&now);
      if ( mytime )
      {
         char year [ 5 ];
         if ( strftime(year, sizeof year, "%Y", mytime) )
         {
            return atoi(year);
         }
      }
    }
    return 0;
}

void read_list_from_bin_file(char* filename){
    FILE* fp = fopen(filename,"rb");
    int number_of_elements;
    int i;
    if(fp!=NULL){
        fread(&number_of_elements,4,1,fp);
        Firm* temp = head;
        for(i = 0;i<number_of_elements;i++){
            temp->next = (struct Firm*)malloc(sizeof(Firm));
            temp = (Firm*)(temp->next);
            fread(temp,sizeof(Firm),1,fp);
        }
        temp -> next = NULL;
    }else{
        printf("\t---file open error!---\n");
    }
}

void save_list_to_bin_file(const char* filename){
    FILE* fp = fopen(filename,"wb");
    int number_of_elements = get_size();
    if(fp!=NULL){
        fwrite(&number_of_elements,4,1,fp);
        Firm* temp = head;
        while(temp->next!=NULL){
            temp = (Firm*)(temp->next);
            fwrite(temp,sizeof(Firm),1,fp);
        }
    }else{
        printf("\t---File can\'t be created! :(---\n");
    }
}
char* add_txt_at_the_end_of_the_file(char* filename){
    char* new_name = (char*)malloc(18);
    int i;
    for(i=0;filename[i]!='\0';i++){
        new_name[i] = filename[i];
    }
    new_name[i] = '.';
    i++;
    new_name[i] = 't';
    i++;
    new_name[i] = 'x';
    i++;
    new_name[i] = 't';
    i++;
    new_name[i] = '\0';
    return new_name;
}

void save_a_firm_into_a_text_file_by_address(Firm* address){
    int i;
    int current_year = get_current_year();
    printf("%s \n",address->tax_registry_number);
    /*char*  filename = add_txt_at_the_end_of_the_file(address->tax_registry_number);
    FILE* fp = fopen(filename,"w");
    if(fp!=NULL){
        fprintf(fp,"%s\n",address->name);
        for(i=0;i<5;i++){
            current_year--;
            fprintf(fp,"earning for %d year = %.2f\n",current_year,(address->earnings)[i]);
        }
        fprintf(fp,"date of registration: %s\n",(address->date_of_registration));
        fclose(fp);
        free(filename);
    }else{
        printf("\t---File can\'t be created! :(---\n");
    }*/
}

void save_all_firms_into_text_files(){
    Firm* temp = head;
    while(temp->next!=NULL){
        temp = (Firm*)(temp->next);
        save_a_firm_into_a_text_file_by_address(temp);
    }
}

int get_size(){
    Firm* temp = head;
    int size = 0;

    while(temp->next!=NULL){
        temp = (Firm*)temp->next;
        ++size;
    }
    return size;
}
void free_list(){
    Firm* temp = head;
    Firm* next;
    while(head->next!=NULL){
        temp = (Firm*)(temp->next);
        next = (Firm*)(temp->next);
        free(temp);
        head->next = (struct Firm*)next;
    }
    free(head);
    head = NULL;
}
void reconstruct_list(){
    if(head != NULL){
        free_list();
    }
    head = (Firm*)malloc(sizeof(Firm));
    head->next = NULL;
}

int check_format_of_date(char* date){
    if(!((date[0]<='9')&&(date[0]>='0'))){
        return 0;
    }
    if(!((date[1]<='9')&&(date[1]>='0'))){
        return 0;
    }
    if(!((date[2]<='9')&&(date[2]>='0'))){
        return 0;
    }
    if(!((date[3]<='9')&&(date[3]>='0'))){
        return 0;
    }
    if(date[4]!='.'){
        return 0;
    }
    if(!((date[5]<='9')&&(date[0]>='0'))){
        return 0;
    }
    if(!((date[6]<='9')&&(date[0]>='0'))){
        return 0;
    }
    if(date[7]!='.'){
        return 0;
    }
    if(!((date[8]<='9')&&(date[0]>='0'))){
        return 0;
    }
    if(!((date[9]<='9')&&(date[0]>='0'))){
        return 0;
    }
    return 1;
}

char* get_registry_tax_number(){
    char* tax_number = (char*)malloc(13);
    int first_time = 1;
    do{
        if(!first_time){
            printf("\t---tax registry number must be 13 chars---\n");
        }
        printf("\t Enter tax registry number: ");
        fflush(stdin);
        scanf("%s",tax_number);
        first_time = 0;
    }while(strlen(tax_number)<13);
    return tax_number;
}
void add_new_firm(){
    char* tax_number;
    printf("\tadding new firm\n");
    Firm* temp = head;
    while(temp->next!=NULL){
        temp = (Firm*)(temp->next);
    }
    tax_number = get_registry_tax_number();
    strcpy(temp->tax_registry_number,tax_number);
    free(tax_number);
    temp->next = (struct Firm*)malloc(sizeof(Firm));
    temp = (Firm*)(temp->next);
    temp -> next = NULL;

    input_info_on_address(temp);
    save_list_to_bin_file(BIN_FILENAME);
    save_all_firms_into_text_files();
}

void input_info_on_address(Firm* address){
    printf("\t Enter new firm name: ");
    fflush(stdin);
    fgets(address->name,41,stdin);
    //printf("%s",address->name);

    char* date;
    date = get_date(" ");
    strcpy(address->date_of_registration,date);
    free(date);
    int current_year;
    int i;
    current_year = get_current_year();
    for(i = 0;i < 5;i++){
        current_year--;
        printf("\t Enter new average earnings for %d year: ",current_year);
        fflush(stdin);
        scanf("%f",&((address->earnings)[i]));//(address->earnings)+i;
    }
}

void update_firm(){
    char tax_registry_number[14];
    printf("\tupdate firm\n");
    printf("\t enter tax registry number of the firm you want update: ");
    fflush(stdin);
    scanf("%s",tax_registry_number);
    int if_found_firm = 0;
    Firm* temp = head;
    while(temp->next!=NULL){
        temp = (Firm*)(temp->next);
        if(strcmp(tax_registry_number,temp->tax_registry_number)==0){
            input_info_on_address(temp);
            if_found_firm = 1;
        }
    }
    if(!if_found_firm){
        printf("\t---firm not found---\n");
    }
    save_list_to_bin_file(BIN_FILENAME);
    save_all_firms_into_text_files();
}
void show_information_for_firm_by_tax_registration_number(){
    int if_found_firm = 0;
    char tax_registry_number[14];
    printf("\tshow info for firm by tax registration number\n");
    printf("\t enter tax registry number of the firm you want search for: ");
    fflush(stdin);
    scanf("%s",tax_registry_number);
    Firm* temp = head;
    while(temp->next!=NULL){
        temp = (Firm*)(temp->next);
        if(strcmp(temp->tax_registry_number,tax_registry_number)==0){
            if_found_firm = 1;
            print_info_by_address(temp);
        }
    }
    if(!if_found_firm){
        printf("\t---firm not found---\n");
    }
}
char* get_date(const char* type_of_date){
    char* date = (char*)malloc(11);
    int first_time = 1;
    do{
        if(first_time==0){
            printf("\t---Date format error, the format must be \"YYYY.DD.MM\"!---\n");
        }
        printf("\t Enter%sdate [YYYY.DD.MM]: ",type_of_date);
        fflush(stdin);
        scanf("%s",date);
        first_time = 0;
    }while(!check_format_of_date(date));
    return date;
}

void show_info_for_firms_in_interval(){
    int i;
    int if_all_earnings_are_positive;
    printf("\tprinting all firms with earnings for all 5 years in custom interval!\n");
    char* start_date = get_date(" start ");
    char* final_date = get_date(" final ");
    char* reversed_start_date = get_reversed_date(start_date);
    char* reversed_final_date = get_reversed_date(final_date);
    free(start_date);
    free(final_date);
    char* reversed_current_date;
    Firm* temp = head;
    int something_found = 0;
    while(temp->next!=NULL){
        temp = (Firm*)(temp->next);
        if_all_earnings_are_positive = 1;
        reversed_current_date = get_reversed_date(temp->date_of_registration);
        if((strcmp(reversed_start_date,reversed_current_date)<=0)&&(strcmp(reversed_final_date,reversed_current_date)>=0)){
            //printf("\tstart = %s; current = %s; final = %s\n",reversed_start_date,reversed_current_date,reversed_final_date);
            for(i = 0;i<5;i++){
                if((temp->earnings)[i]<=0){
                    if_all_earnings_are_positive = 0;
                }
            }
            if(if_all_earnings_are_positive){
                print_info_by_address(temp);
            }
            something_found = 1;
        }
        free(reversed_current_date);
    }
    if(!something_found){
        printf("\t---not found firms in interval [%s;%s]---\n",reversed_start_date,reversed_final_date);
    }
    free(reversed_start_date);
    free(reversed_final_date);
}
void print_info_by_address(Firm* address){
    Firm* temp = head;
    while(temp->next!=NULL){
        temp = (Firm*)(temp->next);
        if(temp==address){
            printf("\n\t tax registry number: %s\n",temp->tax_registry_number);
            printf("\t firm name: %s\n",temp->name);
            printf("\t date of registration: %s\n",temp->date_of_registration);


            int current_year;
            int i;
            current_year = get_current_year();
            for(i = 0;i < 5;i++){
                current_year--;
                printf("\t earnings for %d year: %f\n",current_year,temp->earnings[i]);
            }
        }
    }
}
int menu(){
    printf("MENU\n");
    printf("1. add_new_firm();\n");
    printf("2. update_firm();\n");
    printf("3. show_info_for_firms_in_interval();\n");
    printf("4. show_information_for_firm_by_tax_registration_number();\n");
    printf("5. exit\n");
    char option;
    fflush(stdin);
    scanf("%c",&option);
    switch(option){
        case '1':add_new_firm();return 0;
        case '2':update_firm();return 0;
        case '3':show_info_for_firms_in_interval();return 0;
        case '4':show_information_for_firm_by_tax_registration_number();return 0;
        default:return -1;
    }
}


int main(){
    char c;
    reconstruct_list();
    read_list_from_bin_file(BIN_FILENAME);
    while(menu()==0){
        printf("\t===press enter to return menu===\n");
        fflush(stdin);
        scanf("%c",&c);
    }

    return 0;
}