2023-2-WS_group_project_theadmirals/src/operationHandler.c

#include "operationHandler.h"
#include <stdbool.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>

// checking integer input as operation id
bool checkOperationInput(int input) {
    switch (input) {
        case 4: case 3: case 2: case 1:
            return true;
    }
    return false;
}

// full input process
int* evaluateInput(char* input, int operation) {
    // check if formatting is correct
    if(!containsTwoNumbers(input)) return NULL;
    int firstNumber = extractFirstNumber(input);
    // origin string "input" has been edited
    int secondNumber = atoi(input);
    int* result = malloc(sizeof(int));
    switch (operation) {
        case 1:
            *result = firstNumber + secondNumber;
            break;
        case 2:
            *result = firstNumber - secondNumber;
            break;
        case 3:
            *result = firstNumber * secondNumber;
            break;
        case 4:
            *result = firstNumber / secondNumber;
            break;
    }
    return result;
}

// formatting check of string
bool containsTwoNumbers(const char* str) {
    int numbersCount = 0;
    bool hasSpace = false;
    bool isInNumber = false;

    for (int i = 0; str[i] != '\0'; i++) {
        if (isdigit(str[i])) {
            if (!isInNumber) {
                isInNumber = true;
                numbersCount++;
            }
        } else if (str[i] == ' ' && isInNumber) {
            hasSpace = true;
            isInNumber = false;
        } else if (str[i] == ' ' && !isInNumber) {
            hasSpace = false;
        } else {
            hasSpace = false;
            isInNumber = false;
        }
    }
    return (numbersCount == 2 && hasSpace);
}

// extracting of first number and removing from string
int extractFirstNumber(char* str) {
    int number = 0;
    bool isInNumber = false;
    int endIndex = 0;

    for (int i = 0; str[i] != '\0'; i++) {
        if (isdigit(str[i])) {
            if (!isInNumber) {
                isInNumber = true;
                number = str[i] - '0';
            } else {
                number = number * 10 + (str[i] - '0');
            }
        } else if (str[i] == ' ' && isInNumber) {
            endIndex = i;
            break;
        } else {
            isInNumber = false;
        }
    }

    int index = 0;
    char temp[strlen(str)-endIndex+1];
    for(int i = endIndex+1; i < strlen(str); i++) {
        temp[index++] = str[i];
    }
    temp[index] = '\0';
    strcpy(str, temp);

    return number;
}

void outputInteger(int output) {
    outputTemplate();
    printf("Result: %d", output);
}

void outputLong(long output) {
    outputTemplate();
    printf("Result: %ld", output);
}

void outputDouble(double output) {
    outputTemplate();
    printf("Result: %lf", output);
}

void outputFloat(float output) {
    outputTemplate();
    printf("Result: %f", output);
}

void outputTemplate() {
    printf("###############################\n-> Calculator\n#################################");
}