main.py

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+import sys
+import platform
+
+def encode(m):
+    m = bytearray(m, "ascii")
+    message = format(int.from_bytes(m, "big"), "b")
+    generator = "10001000000100001"
+    gen_deg = len(generator)
+
+    message += "0" * (gen_deg - 1)
+    while len(message) % 8 != 0:
+        message = "0" + message
+
+    swapped = list(message)
+    for i in range(gen_deg - 1):
+        if swapped[i] == "0":
+            swapped[i] = "1"
+        else:
+            swapped[i] = "0"
+
+    message = "".join(swapped)
+
+    while True:
+
+        if message[0] == "0":
+            message = message[1:]
+        else:
+            chunk = message[:gen_deg]
+
+            if len(chunk) < gen_deg:
+
+                while len(chunk) % 8 != 0:
+                    chunk = "0" + chunk
+
+                fb = str(hex(int(chunk[:8], 2)))[2:]
+
+                if len(fb) == 1:
+                    fb = "0" + fb
+
+                sb = str(hex(int(chunk[8:], 2)))[2:]
+
+                if len(sb) == 1:
+                    sb = "0" + sb
+
+                m += b"\\x" + bytes(fb, "ascii")
+                m += b"\\x" + bytes(sb, "ascii")
+                return m
+
+            remainder = format(int(chunk, 2) ^ int(generator, 2), "b")
+            message = remainder + message[gen_deg:]
+
+
+def decode(n):
+
+    if platform.system() == "Windows":
+        n = n.split("\\\\x")
+    else:
+        n = n.split("\\x")
+
+    msg = n[0]
+    message = ""
+
+    for ch in msg:
+
+        ch = bin(ord(ch))[2:]
+
+        while len(ch) < 8:
+            ch = "0" + ch
+
+        message += str(ch)
+
+    fb = bin(int(n[1], 16))[2:]
+
+    while len(fb) < 8:
+        fb = "0" + fb
+
+    sb = bin(int(n[2], 16))[2:]
+
+    while len(sb) < 8:
+        sb = "0" + sb
+
+    message += fb + sb
+    generator = "10001000000100001"
+    gen_deg = len(generator)
+
+    while len(message) % 8 != 0:
+        message = "0" + message
+
+    swapped = list(message)
+    for i in range(gen_deg - 1):
+        if swapped[i] == "0":
+            swapped[i] = "1"
+        else:
+            swapped[i] = "0"
+
+    message = "".join(swapped)
+
+    while True:
+
+        if '1' not in message:
+            return True
+
+        if message[0] == "0":
+            message = message[1:]
+        else:
+            chunk = message[:gen_deg]
+
+            if len(chunk) < gen_deg:
+                return False
+
+            remainder = format(int(chunk, 2) ^ int(generator, 2), "b")
+            message = remainder + message[gen_deg:]
+
+
+if __name__ == "__main__":
+
+    if len(sys.argv) < 2:
+        print("Proszę wprowadzić jedną z flag:\n")
+        print("  -e, --encode\tZakoduj <wiadomość>")
+        print("  -d, --decode\tDekoduj <wiadomość_z_ramką>\n")
+        print("Przykład:")
+        print("python main.py -e abc")
+        print("python main.py -d abc\\\\x51\\\\x4a")
+    else:
+        if sys.argv[1] == "-e" or sys.argv[1] == "--encode":
+            print(encode(sys.argv[2]))
+        elif sys.argv[1] == "-d" or sys.argv[1] == "--decode":
+            print(decode(sys.argv[2]))
+
+
+