#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef enum { RON, EUR, GBP } Currency;
typedef enum { user, admin } UserType;


typedef struct account { // definire sublista
    struct account* urm; //  inlantuire
    Currency currency;
    float sold;
    char iban[20];// elemente lista
}account;

typedef struct User { // definire lista
    struct User* urm; // prima inlantuire
    struct account* headAccount; // radacina pentru conturi
    struct account* tailAccount; // ultima adresa a sublistei conturi
    char username[20], cnp[13], pass[20];// elemente lista
    UserType userType;
}User;

struct User* UserLogged = NULL;

const char* TypeUserToString(UserType userType) {
    switch (userType)
    {
    case user: return "user"; break;
    case admin: return "admin"; break;
    default: return "nedefinit";
    break;
    }
}
enum UserType stringToUserType(const char* userType) {
    if (strcmp("user", userType) == 0) return user;
    if (strcmp("admin", userType) == 0) return admin;
    return user;
}

const char* currencyToString(Currency currency) {
    switch (currency)
    {
    case RON: return "RON"; break;
    case EUR: return "EUR"; break;
    case GBP: return "GBP"; break;
    default: return "nedefinit";
        break;
    }
}
enum Currency stringToCurrency(const char* currency) {
    if (strcmp("RON", currency) == 0) return RON;
    if (strcmp("EUR", currency) == 0) return EUR;
    if (strcmp("GBP", currency) == 0) return GBP;
    return RON;
}

struct account* SearchAccount(struct account* head, const char *iban) {
    struct account* q = head;
    while (q) {
        if (strcmp(q->iban, iban) == 0) return q;
        q = q->urm;
    }
    return NULL;
}
struct User* AddToEndAccount(struct User* user, struct account* p) {
    if (user->headAccount == NULL) {
        user->headAccount = p;
        user->tailAccount = p;
    }
    else {
        user->tailAccount->urm = p;
        user->tailAccount = p;
    }
    return user;
}
void RemoveAllAccounts(struct account* head) {
    struct account* aux;
    while (head) {
        aux = head;
        head = head->urm;
        free(aux);
    }

}
void ShowAccounts(struct account* headAccount) {
    struct account* q = headAccount;
    printf("--------------------------------------\n");
    while (q) {
        printf("Iban = %s moneda =  %s\n", q->iban, currencyToString(q->currency));
        q = q->urm;
    }
    printf("--------------------------------------\n");
}

struct User* SearchUserByUsername(struct User* head, const char* username) {
    struct User* q = head;
    while (q) {
        if (strcmp(q->username, username) == 0) return q;
        q = q->urm;
    }
    return NULL;
}

struct User* SearchUserByCNP(struct User* head, const char* cnp) {
    struct User* q = head;
    while (q) {
        if (strcmp(q->cnp, cnp) == 0) return q;
        q = q->urm;
    }
    return NULL;
}
struct User* AddSortedUser(struct User* head, struct User* p) {// functia de adaugare sortata
    struct User* q = head;// User folosit pentru parcurgea listei
    if (head == NULL) // (!head) verificam daca sunt elemente in lista
    {
        head = p;// daca nu sunt capul listel devine noul element
    }
    else if (strcmp(head->username, p->username) > 0) { // verificam daca elementul adaugat trebuie adaugat in capul listei
        p->urm = head; //elementul aduaugat va avea in pareta dreapta lista existenta
        head = p; // noul element va devieni capatul(radidacian listi)
        return head;
    }
    else {
        while (q->urm != NULL && strcmp(q->urm->username, p->username) < 0) { // parcurgem lista ca sa gasim pozitia de inserare
            q = q->urm;// parcurgere lista
        }
        p->urm = q->urm;// elementu nou va avea in dreapta ce avea poztia la care s-a gasit inserarea
        q->urm = p;
    }
    return head;
}
struct User* RemoveUser(struct User* head, char username[]) { //sterge User
    struct User* aux = NULL, * q = NULL;// Userul aux este pentreu retinire tempara User sters, q este folosit pentru parcurgere
    if (head == NULL) {// verificam daca capul este null altfel return null ca si adresa
        return NULL;
    }
    else if (strcmp(head->username, username) == 0) {// verificam daca este capul listei Userul sters
        aux = head;// salvam temporar Userul
        head = head->urm;// capul devine umaatorul element
        RemoveAllAccounts(aux->headAccount);
        free(aux);// returnam adresa Userul pe care vrem sa-l stergem in caz ce se vrea prelucat ceva dupa
        return head;
    }
    else {
        q = head;// daca nu e la inceput parcurgem lista
        while (q->urm != NULL && strcmp(q->urm->username, username) != 0) {// ca la adaugarea sorata cautam pozita anterioara Userul pe care vrem sa-l stergem
            q = q->urm;// parcurgem lista
        }
        if (q->urm == NULL) {// daca s-a ajuns la sfarsitul listei si nu s-a gasit
            return;// returnam null deoarece Userul nu se afla in lista
        }
        else {
            aux = q->urm;// altfel salvam Userul urmator(Userul ce trebuie stres)
            q->urm = q->urm->urm;// Userul anterior va pointa catre Userul din dtreapa celui sters
            RemoveAllAccounts(aux->headAccount);
            free(aux);// returnam Userul pe care vrem sa-l stergem
        }
        return head;
    }
}
void ShowUsers(struct User* head) {// toat functiile le am implementat sa primeasca head deaorece e mai ok asa
    struct User* p = head;// ne punem pe capul listei

    while (p != NULL) {// cat timp nu s-a ajuns la sfarsitul fiserului
        printf("username = %s\nCNP = %s\n", p->username, p->cnp);// afisam datele despre utilziator
        ShowAccounts(p->headAccount);
        p = p->urm;// parcurgem lista
    }
}
void LoginUser(struct User* head) {
    char username[20], pass[20];
    struct User* user;
    printf("\nusername: "); scanf_s("%s", username, sizeof(username));
    printf("\npassword: "); scanf_s("%s", pass,sizeof(pass));
    user = SearchUserByUsername(head, username);
    if (user) {
        if (strcmp(user->pass, pass) == 0) {
            UserLogged = user;
        }
        else {
            printf("\nParola este gresita");
        }
    }
    else
    {
        printf("\nUtilizatorul nu a fost gasit");
    }
}

void MeniuUser(struct User* head) {
    int opt;
    do {
        printf("\n0. Dezautentificare");
        printf("\nOptiunea aleasa: "); scanf_s("%d", &opt);
        switch (opt)
        {
        case 0:
            UserLogged = NULL;
        default:
            break;
        }
    } while (opt);
}

void MeniuAdmin(struct User* head) {
    int opt;
    do {
        printf("\n0. Dezautentificare");
        printf("\nOptiunea aleasa: "); scanf_s("%d", &opt);
        switch (opt)
        {
        case 0:
            UserLogged = NULL;
        default:
            break;
        }
    } while (opt);
}

struct User* ReadUsersFromFile(const char* filePath) {
    struct User* p, * q = NULL;// Userul nou adaugat
    struct User* head = NULL;// capul listei de utilizatori
    FILE* f = NULL;
    char userTpe[20];
    fopen_s(&f, filePath, "r");
    if (f == NULL) {
        printf("Fiserul de utilizatori nu a putut fi deschis");
        return NULL;
    }
    while (!feof(f))
    {
        p = (struct User*)malloc(sizeof(struct User));
        fscanf_s(f, "%s", p->username, sizeof(p->username)); // fscanf_s pentru siruri si caractere necesita si numarul de elemente maxim citit
        fscanf_s(f, "%s", p->pass, sizeof(p->pass)); // fscanf_s pentru siruri si caractere necesita si numarul de elemente maxim citit
        fscanf_s(f, "%s", userTpe, sizeof(userTpe)); // fscanf_s pentru siruri si caractere necesita si numarul de elemente maxim citit
        p->userType = stringToUserType(userTpe);
        fscanf_s(f, "%s%*c", p->cnp, sizeof(p->cnp)); // %*c se foloseste pentru a citi \n de la sfarst de rand si face discard
        p->urm = NULL;
        p->headAccount = NULL;
        p->tailAccount = NULL;
        q = SearchUserByCNP(head, p->cnp);
        if (q || feof(f) || SearchUserByUsername(head, p->username)) {
            free(p);
        }
        else {
            head = AddSortedUser(head, p);
        }
    }
    fclose(f);
    return head;
}
void ReadAccountsFromFile(struct User* head, const char* filePath) {
    struct User* q = NULL;

    struct account* aux = NULL, * temp = NULL;
    char cnp[13], currency[13];
    FILE* f = NULL;


    fopen_s(&f, filePath, "r");

    while (!feof(f))
    {
        aux = (struct account*)malloc(sizeof(struct account));
        fscanf_s(f, "%s", cnp, sizeof(cnp));// fscanf_s pentru siruri si caractere necesita si numarul de elemente maxim citit
        fscanf_s(f, "%s", aux->iban, sizeof(aux->iban));// fscanf_s pentru siruri si caractere necesita si numarul de elemente maxim citit
        fscanf_s(f, "%s", currency, sizeof(currency));// fscanf_s pentru siruri si caractere necesita si numarul de elemente maxim citit
        fscanf_s(f, "%g%*c", &aux->sold);// %*c se foloseste pentru a citi \n de la sfarsit de rand si face discard
        aux->currency = stringToCurrency(currency);
        aux->urm = NULL;
        q = SearchUserByCNP(head, cnp);
        if (!q) {
            free(aux);
            printf("Nu s-a gasit utilizatorul cu cnp %s\n", cnp);
            continue;
        }
        else {
            temp = SearchAccount(q->headAccount, aux->iban);
            if (temp) {
                printf("Contul cu IBAN %s exista deja\n", aux->iban);
                free(aux);
            }
            else {
                AddToEndAccount(q, aux);
            }
        }
    }

}

int main()
{
    struct User* head = NULL;// capul listei de utilizatori
    head = ReadUsersFromFile("users.txt");
    ReadAccountsFromFile(head, "accounts.txt");
    int opt;
    do {
        printf("\n0. Iesire");
        printf("\n1. Autenitifcare");
        printf("\nOptiunea aleasa: "); scanf_s("%d", &opt);
        if (opt == 1) {
            LoginUser(head);
            if (UserLogged) {
                if (UserLogged->userType == user) MeniuUser(head);
                else MeniuAdmin(head);
            }
        }


    } while (opt);
    ShowUsers(head);

}