diff --git a/.gitignore b/.gitignore
index c09abac..8d946db 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,7 @@
 *.pyc
 *.pyo
 *.egg-info
+*.coverage
 __pycache__
 bin
 build
diff --git a/pyproject.toml b/pyproject.toml
index bd50594..4039df2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -43,7 +43,7 @@ version = {attr = "otpauth.__version__"}
 where = ["src"]
 
 [tool.pytest.ini_options]
-pythonpath = ["src", "."]
+pythonpath = ["src"]
 testpaths = ["tests"]
 filterwarnings = ["error"]
 
diff --git a/src/otpauth/core.py b/src/otpauth/core.py
index 1a8362a..904cb49 100644
--- a/src/otpauth/core.py
+++ b/src/otpauth/core.py
@@ -1,4 +1,5 @@
 import base64
+import typing as t
 from urllib.parse import quote
 from abc import ABCMeta, abstractmethod
 
@@ -16,28 +17,34 @@ def __init__(self, secret: bytes, digit: int = 6, algorithm: str = "SHA1"):
         self._b32_secret = None
 
     @property
-    def b32_secret(self) -> bytes:
+    def b32_secret(self) -> str:
         if self._b32_secret:
             return self._b32_secret
 
         secret = base64.b32encode(self.secret)
-        self._b32_secret = secret.rstrip(b'=')
+        self._b32_secret = secret.rstrip(b'=').decode("ascii")
         return self._b32_secret
 
     @classmethod
-    def from_b32encode(cls, secret: bytes):
+    def from_b32encode(cls, secret: t.AnyStr):
+        if isinstance(secret, str):
+            secret = secret.encode("utf-8")
+
         b32_secret = secret.rstrip(b'=')
 
         # add padding back
         secret += b'=' * (-len(secret) % 8)
         raw_secret = base64.b32decode(secret)
+
         obj = cls(raw_secret)
-        obj._b32_secret = b32_secret
+        obj._b32_secret = b32_secret.decode("ascii")
         return obj
 
     def _get_base_uri(self, label: str, issuer: str) -> str:
-        label = quote(label, safe="/@")
-        return f"otpauth://hotp/{label}?secret={self.b32_secret}&issuer={issuer}&algorithm={self.algorithm}&digits={self.digit}"
+        label = quote(label, safe="/@:")
+        issuer = quote(issuer, safe="")
+        _type = self.TYPE.lower()
+        return f"otpauth://{_type}/{label}?secret={self.b32_secret}&issuer={issuer}&algorithm={self.algorithm}&digits={self.digit}"
 
     @abstractmethod
     def generate(self, *args, **kwargs) -> int:
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/test_hotp.py b/tests/test_hotp.py
new file mode 100644
index 0000000..2c0cf2c
--- /dev/null
+++ b/tests/test_hotp.py
@@ -0,0 +1,46 @@
+import unittest
+from otpauth import HOTP
+
+
+class TestHOTP(unittest.TestCase):
+    def setUp(self):
+        self.hotp = HOTP(b"python")
+
+    def test_generate(self):
+        value = self.hotp.generate(0)
+        self.assertEqual(value, 170566)
+
+    def test_verify(self):
+        # due to number too long
+        self.assertFalse(self.hotp.verify(12345678, 0))
+
+        # due to not match
+        self.assertFalse(self.hotp.verify(12345, 0))
+
+        self.assertTrue(self.hotp.verify(170566, 0))
+
+    def test_to_uri(self):
+        uri = self.hotp.to_uri("Typlog:lepture.com", "Authlib", 0)
+        expected = "otpauth://hotp/Typlog:lepture.com?secret=OB4XI2DPNY&issuer=Authlib&algorithm=SHA1&digits=6&counter=0"
+        self.assertEqual(uri, expected)
+
+    def test_from_b32encode(self):
+        expected = "otpauth://hotp/Typlog:lepture.com?secret=OB4XI2DPNY&issuer=Authlib&algorithm=SHA1&digits=6&counter=0"
+
+        hotp = HOTP.from_b32encode("OB4XI2DPNY")
+        value = hotp.generate(0)
+        self.assertEqual(value, 170566)
+        uri = self.hotp.to_uri("Typlog:lepture.com", "Authlib", 0)
+        self.assertEqual(uri, expected)
+
+        hotp = HOTP.from_b32encode("OB4XI2DPNY======")
+        value = hotp.generate(0)
+        self.assertEqual(value, 170566)
+        uri = self.hotp.to_uri("Typlog:lepture.com", "Authlib", 0)
+        self.assertEqual(uri, expected)
+
+        hotp = HOTP.from_b32encode(b"OB4XI2DPNY======")
+        value = hotp.generate(0)
+        self.assertEqual(value, 170566)
+        uri = self.hotp.to_uri("Typlog:lepture.com", "Authlib", 0)
+        self.assertEqual(uri, expected)
diff --git a/tests/test_totp.py b/tests/test_totp.py
new file mode 100644
index 0000000..7224cb4
--- /dev/null
+++ b/tests/test_totp.py
@@ -0,0 +1,32 @@
+import unittest
+import time
+from otpauth import TOTP
+
+FIXED_TIME = 1679576495
+
+
+class TestTOTP(unittest.TestCase):
+    def setUp(self):
+        self.totp = TOTP(b"python")
+
+    def test_generate(self):
+        value = self.totp.generate(FIXED_TIME)
+        self.assertEqual(value, 129815)
+
+    def test_verify(self):
+        # due to number too long
+        self.assertFalse(self.totp.verify(12345678, FIXED_TIME))
+
+        # due to not match
+        self.assertFalse(self.totp.verify(12345, FIXED_TIME))
+
+        self.assertTrue(self.totp.verify(129815, FIXED_TIME))
+
+    def test_to_uri(self):
+        uri = self.totp.to_uri("Typlog:lepture.com", "Authlib")
+        expected = "otpauth://totp/Typlog:lepture.com?secret=OB4XI2DPNY&issuer=Authlib&algorithm=SHA1&digits=6&period=30"
+        self.assertEqual(uri, expected)
+
+    def test_current_timestamp(self):
+        value = self.totp.generate()
+        self.assertTrue(self.totp.verify(value))