#
#  Copyright 2025 The InfiniFlow Authors. All Rights Reserved.
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#  Licensed under the Apache License, Version 2.0 (the "License");
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
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#      http://www.apache.org/licenses/LICENSE-2.0
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#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#  See the License for the specific language governing permissions and
#  limitations under the License.
#
import uuid
import hashlib
from common.misc_utils import get_uuid, download_img, hash_str2int


class TestGetUuid:
    """Test cases for get_uuid function"""

    def test_returns_string(self):
        """Test that function returns a string"""
        result = get_uuid()
        assert isinstance(result, str)

    def test_hex_format(self):
        """Test that returned string is in hex format"""
        result = get_uuid()
        # UUID v1 hex should be 32 characters (without dashes)
        assert len(result) == 32
        # Should only contain hexadecimal characters
        assert all(c in '0123456789abcdef' for c in result)

    def test_no_dashes_in_result(self):
        """Test that result contains no dashes"""
        result = get_uuid()
        assert '-' not in result

    def test_unique_results(self):
        """Test that multiple calls return different UUIDs"""
        results = [get_uuid() for _ in range(10)]

        # All results should be unique
        assert len(results) == len(set(results))

        # All should be valid hex strings of correct length
        for result in results:
            assert len(result) == 32
            assert all(c in '0123456789abcdef' for c in result)

    def test_valid_uuid_structure(self):
        """Test that the hex string can be converted back to UUID"""
        result = get_uuid()

        # Should be able to create UUID from the hex string
        reconstructed_uuid = uuid.UUID(hex=result)
        assert isinstance(reconstructed_uuid, uuid.UUID)

        # The hex representation should match the original
        assert reconstructed_uuid.hex == result

    def test_uuid1_specific_characteristics(self):
        """Test that UUID v1 characteristics are present"""
        result = get_uuid()
        uuid_obj = uuid.UUID(hex=result)

        # UUID v1 should have version 1
        assert uuid_obj.version == 1

        # Variant should be RFC 4122
        assert uuid_obj.variant == 'specified in RFC 4122'

    def test_result_length_consistency(self):
        """Test that all generated UUIDs have consistent length"""
        for _ in range(100):
            result = get_uuid()
            assert len(result) == 32

    def test_hex_characters_only(self):
        """Test that only valid hex characters are used"""
        for _ in range(100):
            result = get_uuid()
            # Should only contain lowercase hex characters (UUID hex is lowercase)
            assert result.islower()
            assert all(c in '0123456789abcdef' for c in result)


class TestDownloadImg:
    """Test cases for download_img function"""

    def test_empty_url_returns_empty_string(self):
        """Test that empty URL returns empty string"""
        result = download_img("")
        assert result == ""

    def test_none_url_returns_empty_string(self):
        """Test that None URL returns empty string"""
        result = download_img(None)
        assert result == ""


class TestHashStr2Int:
    """Test cases for hash_str2int function"""

    def test_basic_hashing(self):
        """Test basic string hashing functionality"""
        result = hash_str2int("hello")
        assert isinstance(result, int)
        assert 0 <= result < 10 ** 8

    def test_default_mod_value(self):
        """Test that default mod value is 10^8"""
        result = hash_str2int("test")
        assert 0 <= result < 10 ** 8

    def test_custom_mod_value(self):
        """Test with custom mod value"""
        result = hash_str2int("test", mod=1000)
        assert isinstance(result, int)
        assert 0 <= result < 1000

    def test_same_input_same_output(self):
        """Test that same input produces same output"""
        result1 = hash_str2int("consistent")
        result2 = hash_str2int("consistent")
        result3 = hash_str2int("consistent")

        assert result1 == result2 == result3

    def test_different_input_different_output(self):
        """Test that different inputs produce different outputs (usually)"""
        result1 = hash_str2int("hello")
        result2 = hash_str2int("world")
        result3 = hash_str2int("hello world")

        # While hash collisions are possible, they're very unlikely for these inputs
        results = [result1, result2, result3]
        assert len(set(results)) == len(results)

    def test_empty_string(self):
        """Test hashing empty string"""
        result = hash_str2int("")
        assert isinstance(result, int)
        assert 0 <= result < 10 ** 8

    def test_unicode_string(self):
        """Test hashing unicode strings"""
        test_strings = [
            "中文",
            "🚀火箭",
            "café",
            "🎉",
            "Hello 世界"
        ]

        for test_str in test_strings:
            result = hash_str2int(test_str)
            assert isinstance(result, int)
            assert 0 <= result < 10 ** 8

    def test_special_characters(self):
        """Test hashing strings with special characters"""
        test_strings = [
            "hello@world.com",
            "test#123",
            "line\nwith\nnewlines",
            "tab\tcharacter",
            "space in string"
        ]

        for test_str in test_strings:
            result = hash_str2int(test_str)
            assert isinstance(result, int)
            assert 0 <= result < 10 ** 8

    def test_large_string(self):
        """Test hashing large string"""
        large_string = "x" * 10000
        result = hash_str2int(large_string)
        assert isinstance(result, int)
        assert 0 <= result < 10 ** 8

    def test_mod_value_1(self):
        """Test with mod value 1 (should always return 0)"""
        result = hash_str2int("any string", mod=1)
        assert result == 0

    def test_mod_value_2(self):
        """Test with mod value 2 (should return 0 or 1)"""
        result = hash_str2int("test", mod=2)
        assert result in [0, 1]

    def test_very_large_mod(self):
        """Test with very large mod value"""
        result = hash_str2int("test", mod=10 ** 12)
        assert isinstance(result, int)
        assert 0 <= result < 10 ** 12

    def test_hash_algorithm_sha1(self):
        """Test that SHA1 algorithm is used"""
        test_string = "hello"
        expected_hash = hashlib.sha1(test_string.encode("utf-8")).hexdigest()
        expected_int = int(expected_hash, 16) % (10 ** 8)

        result = hash_str2int(test_string)
        assert result == expected_int

    def test_utf8_encoding(self):
        """Test that UTF-8 encoding is used"""
        # This should work without encoding errors
        result = hash_str2int("café 🎉")
        assert isinstance(result, int)

    def test_range_with_different_mods(self):
        """Test that result is always in correct range for different mod values"""
        test_cases = [
            ("test1", 100),
            ("test2", 1000),
            ("test3", 10000),
            ("test4", 999999),
        ]

        for test_str, mod_val in test_cases:
            result = hash_str2int(test_str, mod=mod_val)
            assert 0 <= result < mod_val

    def test_hexdigest_conversion(self):
        """Test the hexdigest to integer conversion"""
        test_string = "hello"
        hash_obj = hashlib.sha1(test_string.encode("utf-8"))
        hex_digest = hash_obj.hexdigest()
        expected_int = int(hex_digest, 16) % (10 ** 8)

        result = hash_str2int(test_string)
        assert result == expected_int

    def test_consistent_with_direct_calculation(self):
        """Test that function matches direct hashlib usage"""
        test_strings = ["a", "b", "abc", "hello world", "12345"]

        for test_str in test_strings:
            direct_result = int(hashlib.sha1(test_str.encode("utf-8")).hexdigest(), 16) % (10 ** 8)
            function_result = hash_str2int(test_str)
            assert function_result == direct_result

    def test_numeric_strings(self):
        """Test hashing numeric strings"""
        test_strings = ["123", "0", "999999", "3.14159", "-42"]

        for test_str in test_strings:
            result = hash_str2int(test_str)
            assert isinstance(result, int)
            assert 0 <= result < 10 ** 8

    def test_whitespace_strings(self):
        """Test hashing strings with various whitespace"""
        test_strings = [
            "  leading",
            "trailing  ",
            "  both  ",
            "\ttab",
            "new\nline",
            "\r\nwindows"
        ]

        for test_str in test_strings:
            result = hash_str2int(test_str)
            assert isinstance(result, int)
            assert 0 <= result < 10 ** 8