diff --git a/src/reader.py b/src/reader.py
index a70c483..b1b5e44 100644
--- a/src/reader.py
+++ b/src/reader.py
@@ -1,7 +1,9 @@
 import csv
+from dataclasses import dataclass
 import re
 from enum import Enum, auto
 from pathlib import Path
+from typing import Callable
 
 from src.models import B4wExport
 
@@ -17,44 +19,45 @@ def reader_b4w(path: Path):
 
 
 def reader_comdirect(path: Path):
-    PATTERN_ACCOUNT_NAME = r'^"Umsätze ([^"]+)";"Zeitraum: .*$'
-    PATTERN_HEADER = r'"([^"]+)"'
-    PATTERN_DATA = r'"([^"]+)"'
 
-    class EXPECT_LINE(Enum):
-        ACCOUNT_NAME = auto()
-        BLANK = auto()
-        HEADER = auto()
-        DATA = auto()
+    @dataclass
+    class Pattern:
+        pattern: str
+
+        @classmethod
+        def extract_pattern(cls, txt):
+            return re.findall(cls.pattern, txt)
+
+    class EXPECT_LINE(Enum, Pattern):
+        ACCOUNT_NAME = Pattern(r'^"Umsätze ([^"]+)";"Zeitraum: .*$')
+        BLANK = Pattern(r"\n")
+        HEADER = Pattern(r'"([^"]+)"')
+        DATA = Pattern(r'"([^"]+)"')
 
     with path.open(encoding="latin1") as fid:
         lines = fid.readlines()
 
     expect_next = EXPECT_LINE.ACCOUNT_NAME
-    account_name = None
+    account_name = ""
+    header = ""
     result = {}
     for line in lines:
-        if expect_next == EXPECT_LINE.ACCOUNT_NAME:
-            account_name = re.findall(PATTERN_ACCOUNT_NAME, line)
-            if account_name:
-                account_name = account_name[0]
-                result[account_name] = {}
-                expect_next = EXPECT_LINE.BLANK
-        elif expect_next == EXPECT_LINE.BLANK:
-            if line == "\n":
-                expect_next = EXPECT_LINE.HEADER
-        elif expect_next == EXPECT_LINE.HEADER:
-            header = re.findall(PATTERN_HEADER, line)
-            if header:
-                result[account_name]["data"] = []
-                expect_next = EXPECT_LINE.DATA
-        elif expect_next == EXPECT_LINE.DATA:
-            data = re.findall(PATTERN_DATA, line)
-            if data:
-                result[account_name]["data"].append(
-                    {column: value for column, value in zip(header, data)}
-                )
-                expect_next = EXPECT_LINE.ACCOUNT_NAME
+        parsed = expect_next.extract_pattern(line)
+        if expect_next == EXPECT_LINE.ACCOUNT_NAME and parsed:
+            account_name = parsed[0]
+            result[account_name] = {}
+            expect_next = EXPECT_LINE.BLANK
+        elif expect_next == EXPECT_LINE.BLANK and parsed:
+            expect_next = EXPECT_LINE.HEADER
+        elif expect_next == EXPECT_LINE.HEADER and parsed:
+            header = parsed
+            result[account_name]["data"] = []
+            expect_next = EXPECT_LINE.DATA
+        elif expect_next == EXPECT_LINE.DATA and parsed:
+            result[account_name]["data"].append(
+                {column: value for column, value in zip(header, parsed)}
+            )
+            expect_next = EXPECT_LINE.ACCOUNT_NAME
         else:
             expect_next = EXPECT_LINE.ACCOUNT_NAME
     return result