#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>

int main()
{
    menu();
    return 0;
}

void menu(){
    int choice = -1;
    while (choice != 0){
        printf("what do you want to do:\n");
        printf("[0] exit\n");
        printf("[1] add new worker\n");
        printf("[2] list workers\n");
        printf("[3] delete worker\n");
        printf("[4] exit\n");
        scanf("%d", &choice);
        switch(choice){
        case 1:
            newWorker();
            break;
        case 2:
            listWorkers();
            break;
        case 3:
            printf("delete worker");
            break;
        case 0:
            printf("exit");
            break;
        default:
            printf("invalid input\n");
        }
    }
}

void newWorker(){
    int ndays;
    char days[5][10];
    char firstName[100];
    char lastName[100];
    char address[100];
    printf("how many days will the worker work: ");
    scanf("%d", &ndays);
    if(0 < ndays && ndays < 6){
        for(int i = 0; i < ndays; i++){
            printf("Input the %d. day: ", i);
            scanf("%s", &days[i]);
        }
    }else{
        printf("worker can only work 1-5 days a week\n");
        newWorker();
    }
    printf("what is the worker's first name: ");
    scanf("%s", &firstName);
    printf("what is the worker's last name:");
    scanf("%s", &lastName);
    printf("what is the worker's address(no space allowed):");
    scanf("%s", &address);
    char dataLine[50]; //a string to concate the days into
    strcpy(dataLine, days[0]); //copying the first day into the string
    strcat(dataLine, " ");
    for(int i = 1; i < ndays; i++){
        strcat(dataLine, days[i]);
        strcat(dataLine, " ");
    }
    printf("%s\n", dataLine);
    FILE *workerList = fopen("workerlist.txt", "a");
    fprintf(workerList, "%s %s %s %d %s\n", firstName, lastName, address, ndays, dataLine);
    fclose(workerList);
}

void listWorkers(){
    FILE * f;
    f=fopen("workerlist.txt","r");
    if (f==NULL){perror("File opening error\n"); exit(1);}
    char line[350];
    while (!feof(f)){
        fgets(line,sizeof(line),f);
        char lastName[100], firstName[100], address[100];
        strcpy(lastName, strtok(line, " "));
        strcpy(firstName, strtok(NULL, " "));
        strcpy(address, strtok(NULL, " "));
        printf("%s %s lives at %s\n    they are available on: ", lastName, firstName, address);
        char cnDays[100];
        strcpy(cnDays, strtok(NULL, " "));
        int nDays = atoi(cnDays);
        char days[5][10];
        for (int i = 0; i < nDays; i++){
            strcpy(days[i], strtok(NULL, " "));
            printf("%s ", days[i]);
        }
    }
    printf("\n");
    fclose(f);
}