From d602d9c3bae3c40f4c291f8cfae47e9e1d90633f Mon Sep 17 00:00:00 2001
From: Gergely Polonkai <gergely@polonkai.eu>
Date: Thu, 5 May 2022 10:14:34 +0200
Subject: [PATCH] Add very basic Share handling

---
 earthsnake/share.py |  61 ++++++++++++++++++++++++
 tests/test_share.py | 113 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 174 insertions(+)
 create mode 100644 earthsnake/share.py
 create mode 100644 tests/test_share.py

diff --git a/earthsnake/share.py b/earthsnake/share.py
new file mode 100644
index 0000000..aee3eb7
--- /dev/null
+++ b/earthsnake/share.py
@@ -0,0 +1,61 @@
+"""Share handling"""
+
+from random import choice
+import re
+from typing import Optional
+
+from .exc import ValidationError
+from .types import ALPHA_LOWER, ALPHA_LOWER_OR_DIGIT
+
+
+class Share:
+    """Class to handle a share (space or workspace in older terminology)"""
+
+    _NAME_PATTERN = f'[{ALPHA_LOWER}][{ALPHA_LOWER_OR_DIGIT}]{{0,14}}'
+    _SUFFIX_PATTERN = f'[{ALPHA_LOWER}][{ALPHA_LOWER_OR_DIGIT}]{{0,52}}'
+    PATTERN = f'^[+]{_NAME_PATTERN}[.]{_SUFFIX_PATTERN}$'
+
+    def __init__(self, name: str, suffix: Optional[str] = None) -> None:
+        suffix = suffix or self.generate_random_suffix()
+
+        if not re.match(f'^{self._NAME_PATTERN}$', name):
+            raise ValidationError(f'Invalid name "{name}"')
+
+        if not re.match(f'^{self._SUFFIX_PATTERN}$', suffix):
+            raise ValidationError(f'Invalid suffix "{suffix}"')
+
+        self.name = name
+        self.suffix = suffix
+
+    @classmethod
+    def validate_address(cls, share_address: str) -> None:
+        """Check if share_address is a valid share address"""
+
+        if not re.match(cls.PATTERN, share_address):
+            raise ValidationError(f'Invalid share address {share_address}')
+
+    @classmethod
+    def from_address(cls, share_address: str) -> 'Share':
+        """Create a Share object from a share address"""
+
+        cls.validate_address(share_address)
+
+        name, suffix = share_address[1:].split('.')
+
+        return cls(name, suffix)
+
+    @staticmethod
+    def generate_random_suffix(length: int = 53) -> str:
+        """Generate a random share suffix of the desired length"""
+
+        assert 54 > length > 0
+
+        return choice(ALPHA_LOWER) + ''.join(
+            choice(ALPHA_LOWER_OR_DIGIT) for _ in range(length - 1)
+        )
+
+    def __str__(self) -> str:
+        return f'+{self.name}.{self.suffix}'
+
+    def __repr__(self) -> str:
+        return f'<Share {self}>'
diff --git a/tests/test_share.py b/tests/test_share.py
new file mode 100644
index 0000000..817bfb5
--- /dev/null
+++ b/tests/test_share.py
@@ -0,0 +1,113 @@
+"""Tests for the Share class"""
+
+import pytest
+
+from earthsnake.types import ALPHA_LOWER, ALPHA_LOWER_OR_DIGIT
+from earthsnake.exc import ValidationError
+from earthsnake.share import Share
+
+
+@pytest.mark.parametrize(
+    'name,suffix,error',
+    [
+        pytest.param('80smusic', 'suffix', 'Invalid name "80smusic"', id='name_digitstart'),
+        pytest.param('a.b', 'suffix', 'Invalid name "a.b"', id='name_period'),
+        pytest.param('PARTY', 'suffix', 'Invalid name "PARTY"', id='name_uppercase'),
+        pytest.param('test', 'b.c', 'Invalid suffix "b.c"', id='suffix_period'),
+        pytest.param('test', '4ever', 'Invalid suffix "4ever"', id='suffix_digitstart'),
+        pytest.param('test', 'TIME', 'Invalid suffix "TIME"', id='suffix_uppercase'),
+    ],
+)
+def test_create_invalid(name: str, suffix: str, error: str) -> None:
+    """Test if share creation fails with invalid values"""
+
+    with pytest.raises(ValidationError) as ctx:
+        Share(name, suffix=suffix)
+
+    assert str(ctx.value) == error
+
+
+def test_create() -> None:
+    """Test if creating a share with a name and a suffix succeeds"""
+
+    share = Share('test', suffix='suffix')
+
+    assert share.name == 'test'
+    assert share.suffix == 'suffix'
+
+
+def test_create_no_suffix() -> None:
+    """Test if creating succeeds if no suffix is given, and the suffix is randomly chosen"""
+
+    share = Share('test')
+
+    assert share.name == 'test'
+    assert len(share.suffix) == 53
+
+
+def test_str() -> None:
+    """Test the __str__ method"""
+
+    share = Share('test', 'suffix')
+
+    assert str(share) == '+test.suffix'
+
+
+def test_repr() -> None:
+    """Test the __repr__ method"""
+
+    share = Share('test', 'suffix')
+
+    assert repr(share) == '<Share +test.suffix>'
+
+
+@pytest.mark.parametrize(
+    'address',
+    (
+        pytest.param('test.suffix', id='no_prefix'),
+        pytest.param('+t.st.suffix', id='invalid_name_char'),
+    ),
+)
+def test_validate_invalid(address: str) -> None:
+    """Test if validate_address fails if the address is invalid"""
+
+    with pytest.raises(ValidationError) as ctx:
+        Share.validate_address(address)
+
+    assert str(ctx.value) == f'Invalid share address {address}'
+
+
+@pytest.mark.parametrize(
+    'address',
+    (
+        pytest.param('test.suffix', id='no_prefix'),
+        pytest.param('+t.st.suffix', id='invalid_name_char'),
+    ),
+)
+def test_from_address_invalid(address: str) -> None:
+    """Test if from_address fails if the address is invalid"""
+
+    with pytest.raises(ValidationError) as ctx:
+        Share.from_address(address)
+
+    assert str(ctx.value) == f'Invalid share address {address}'
+
+
+def test_from_address() -> None:
+    """Test constructing a share from a string address"""
+
+    share = Share.from_address('+test.suffix')
+
+    assert share.name == 'test'
+    assert share.suffix == 'suffix'
+
+
+@pytest.mark.parametrize('length', range(1, 54))
+def test_generate_suffix(length: int) -> None:
+    """Test the random suffix generator"""
+
+    suffix = Share.generate_random_suffix(length=length)
+
+    assert suffix[0] in ALPHA_LOWER
+    assert all(char in ALPHA_LOWER_OR_DIGIT for char in suffix)
+    assert len(suffix) == length