rework semester functions to better generate offsets

src/backend/semester.py

@@ -1,46 +1,88 @@
 import datetime
+from src.logic.log import logger
+from dataclasses import dataclass
 
+@dataclass
+class Semester:
+    logger.debug("Semester class loaded")
 
-def generateSemesterByDate(next:bool = False):
-    currentYear = datetime.datetime.now().year
-    currentYear = int(str(currentYear)[-2:])
-    month = datetime.datetime.now().month
-    # month = month + 1
-    if next:
-        month += 1
-        if month > 12:
-            month = 1
-            currentYear += 1
-    if month >= 4 and month <= 9:
-        return "SoSe " + str(currentYear)
-    else:
-        if month in [10, 11, 12]:
-            return f"WiSe {currentYear}/{currentYear+1}"
+    _year: int | None = datetime.datetime.now().year
+    _semester: str | None = None
+    _month: int | None = datetime.datetime.now().month
+    value: str = None
+    logger.debug(f"Got values year:{_year}, semester:{_semester}, month:{_month}")
+
+    def __post_init__(self):
+        logger.debug(
+            f"Got values post_init year:{self._year}, semester:{self._semester}, month:{self._month}"
+        )
+
+        if self._year is None:
+            self._year = datetime.datetime.now().year
+        if self._month is None:
+            self._month = datetime.datetime.now().month
+        if self._semester is None:
+            self.generateSemester()
+        self.computeValue()
+
+    def __str__(self):
+        return self.value
+
+    def generateSemester(self):
+        if self._month < 4 or self._month < 9:
+            self._semester = "WiSe"
         else:
-            return f"WiSe {currentYear-1}/{currentYear}"
-        
-        
-def generateSemesterByOffset(offset):
-    currentYear = datetime.datetime.now().year
-    currentYear = int(str(currentYear)[-2:])
-    month = datetime.datetime.now().month
-    #offset represents a single semester
-    semester = generateSemesterByDate()
-    if offset == 1:
-        if semester.startswith("SoSe"):
-            return f"WiSe {currentYear}/{currentYear+1}"
+            self._semester = "SoSe"
+
+    @logger.catch
+    def computeValue(self):
+        # year is only last two digits
+        year = str(self._year)[2:]
+        year = int(year)
+        logger.debug(
+            f"Year is {year}, month is {self._month}, semester is {self._semester}"
+        )
+        if self._semester == "WiSe":
+            if self._month < 4:
+                valueyear = str(year - 1) + "/" + str(year)
         else:
-            return f"SoSe {currentYear+1}"
-    else:
-        #if offset is even, increase the currentyear by offset
-        if offset % 2 == 0:
-            if semester.startswith("SoSe"):
-                return f"SoSe {currentYear+offset//2}"
+            valueyear = str(year)
+        self.value = f"{self._semester} {valueyear}"
+
+    @logger.catch
+    def offset(self, value: int) -> str:
+        """Generate a new Semester object by offsetting the current semester by a given value
+
+        Args:
+            value (int): The value by which the semester should be offset
+
+        Returns:
+            str: the new semester value
+        """
+        assert isinstance(value, int), "Value must be an integer"
+        logger.debug(f"Offsetting semester by {value}")
+        if value == 0:
+            return self
+        if value > 0:
+            if value % 2 == 0:
+                return Semester(self._year + value // 2, self._semester)
             else:
-                return f"WiSe {currentYear+1}/{currentYear+2}"
+                semester = self._semester
+                semester = "SoSe" if semester == "WiSe" else "WiSe"
+                logger.debug(f"Semester is {semester}")
+                return Semester(self._year + value // 2, semester)
         else:
-            return f"WiSe {currentYear+offset//2}/{currentYear+1+offset//2}"
+            if value % 2 == 0:
+                return Semester(self._year - value // 2, self._semester)
+            else:
+                semester = self._semester
+                semester = "SoSe" if semester == "WiSe" else "WiSe"
+                return Semester(self._year + value // 2, semester)
 
+    @property
+    def next(self):
+        return self.offset(1)
 
-if __name__ == "__main__":
-    print(generateSemesterByDate())
+    @property
+    def previous(self):
+        return self.offset(-1)