From d36313dcdc6ea87cfcc95bdf2fdc48227c96bde0 Mon Sep 17 00:00:00 2001
From: Eric Bagus <eric-lars.bagus@informatik.hs-fulda.de>
Date: Thu, 8 Feb 2024 18:05:01 +0100
Subject: [PATCH] Added operation handler method extracting two numbers of
 input

---
 src/operationHandler.c | 55 ++++++++++++++++++++++++++++++++++++++++++
 src/operationHandler.h |  4 +++
 2 files changed, 59 insertions(+)

diff --git a/src/operationHandler.c b/src/operationHandler.c
index ef41efb..616b627 100644
--- a/src/operationHandler.c
+++ b/src/operationHandler.c
@@ -2,6 +2,7 @@
 #include <stdbool.h>
 #include <ctype.h>
 #include <stdlib.h>
+#include <string.h>
 
 bool checkOperationInput(int input) {
     switch (input) {
@@ -11,6 +12,28 @@ bool checkOperationInput(int input) {
     return false;
 }
 
+int* evaluateInput(char* input, int operation) {
+    if(!containsTwoNumbers(input)) return NULL;
+    int firstNumber = extractFirstNumber(input);
+    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;
+}
+
 bool containsTwoNumbers(const char* str) {
     int numbersCount = 0;
     bool hasSpace = false;
@@ -33,4 +56,36 @@ bool containsTwoNumbers(const char* str) {
         }
     }
     return (numbersCount == 2 && hasSpace);
+}
+
+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;
 }
\ No newline at end of file
diff --git a/src/operationHandler.h b/src/operationHandler.h
index cb083e2..58ca89a 100644
--- a/src/operationHandler.h
+++ b/src/operationHandler.h
@@ -4,6 +4,10 @@
 
 bool checkOperationInput(int);
 
+int* evaluateInput(char*, int);
+
 bool containsTwoNumbers(const char*);
 
+int extractFirstNumber(char*);
+
 #endif //THEADMIRALS_OPERATIONHANDLER_H