2022-2-WS_group_project_bankmanagement-system/src/interestCalculator.c

#include "interestCalculator.h"


void troubleshoot(int errorCode){
    printf("Error! The requested operation was terminated because of an issue. Here are some details about the error:\n---------------\n");

    switch(errorCode){
        case 0:
            printf("Principal amount not valid. Make sure it is a valid number over the value of zero.");
            break;
        case 1:
            printf("Interest rate not valid. Make sure it is a valid number over the value of zero.");
            break;
        case 2:
            printf("Duration not valid. Make sure it is a valid number over the value of zero.");
            break;
        case 3:
            printf("Invalid option. Aborting.");
            break;
        case 4:
            printf("Your goal cannot be smaller than your principal funds. Aborting.");
            break;
    }
}

void askForSavingGoal(float principalAmount, float accInterestPerYear) {
    char c;
    float goal;
    float timeForGoal;

    printf("\nWould you like to set a saving goal? [y/n]: ");
    scanf(" %c", &c);

    if (c != 'y' && c != 'Y') {
        return;
    }

    printf("\nPlease enter your goal amount in €: ");
    scanf("%f", &goal);

    if (goal < principalAmount) {
        troubleshoot(4);
        return;
    }

    timeForGoal = (goal - principalAmount) / accInterestPerYear;
    printf("\nIn %.1f years you will reach your goal of %.2f.\n", timeForGoal, goal);
}


float initiateInterest(float principalAmount, float interest, float time){
    return principalAmount*(1+(interest*time));
}

void calculateYearlyInterest(){
    float principalAmount;
    float interestPerYear;
    float timeInYears;
    int choice;

    printf("Please enter the principal amount:");
    if (scanf("%f", &principalAmount) != 1 || principalAmount <= 0) {
        troubleshoot(0);
        return;
    }

    printf("\nPlease enter interest per year (percentage):");
    if (scanf("%f", &interestPerYear) != 1 || interestPerYear <= 0) {
        troubleshoot(0);
        return;
    }
    printf("\nWould you like to enter the time in [1]months or in [2]years?\n");
    scanf("%d",&choice);
    if(choice==1){
        printf("\nPlease enter interest time in months:");
        if (scanf("%f", &timeInYears) != 1 || timeInYears <= 0) {
            troubleshoot(2);
            return;
        }
        timeInYears=timeInYears/12;

    }else if(choice==2){
        printf("\nPlease enter interest time in years:");
        if (scanf("%f", &timeInYears) != 1 || timeInYears <= 0) {
            troubleshoot(2);
            return;
        }
    }else{
        troubleshoot(2);
    }



    float interestDecimal=interestPerYear/100;

    float result= initiateInterest(principalAmount,interestDecimal,timeInYears);
    printf("\nAmount with the interest is %.2f€.",result);
    askForSavingGoal(principalAmount,principalAmount*interestDecimal);
}
void calculateMonthlyInterest(){
    float principalAmount;
    float interestPerMonth;
    float timeInMonths;

    printf("Please enter the principal amount:");
   if (scanf("%f", &principalAmount) != 1 || principalAmount <= 0) {
        troubleshoot(0);
        return;
    }

    printf("\nPlease enter interest per month (percentage):");
    if (scanf("%f", &interestPerMonth) != 1 || interestPerMonth <= 0) {
        troubleshoot(0);
        return;
    }

    printf("\nPlease enter interest time in months:");
    if (scanf("%f", &timeInMonths) != 1 || timeInMonths <= 0) {
        troubleshoot(2);
        return;
    }

    float interestDecimal=interestPerMonth/100;

    float result= initiateInterest(principalAmount,interestDecimal,timeInMonths);
    printf("\nAmount with the interest is %.2f€.",result);
}

void initiateCalculator() {
    int input;
    char c;

    printf("Welcome to the interest calculator. Please select an option:\n"
           "[1] Calculate yearly interest\n"
           "[2] Calculate monthly interest\n");
    scanf("%d", &input);

    switch (input) {
        case 1:
            calculateYearlyInterest();
            break;
        case 2:
            calculateMonthlyInterest();
            break;
        default:
            break;
    }

    printf("\nThank you for using our services. Would you like to do another calculation? [y/n]: ");
    scanf(" %c", &c);

    if (c == 'y' || c == 'Y') {
        initiateCalculator();
    }
}


// int main(){

//     initiateCalculator();

// }