"""
Tests for langbot.pkg.utils.importutil module.

Tests import utility functions:
- import_dir: imports modules from a directory
- import_modules_in_pkg: imports all modules in a package
- import_modules_in_pkgs: imports all modules in multiple packages
- import_dot_style_dir: imports modules using dot notation path
- read_resource_file: reads a text resource file
- read_resource_file_bytes: reads a binary resource file
- list_resource_files: lists files in a resource directory

Uses mocking for import operations to avoid actual module imports.
"""

import pytest
import importlib
import os
from unittest.mock import patch, MagicMock, call


class TestImportDir:
    """Test import_dir function."""

    def test_calls_importlib_for_each_python_file(self, tmp_path, monkeypatch):
        """Should call importlib.import_module for each .py file."""
        module_dir = tmp_path / 'test_modules'
        module_dir.mkdir()

        (module_dir / '__init__.py').write_text('')
        (module_dir / 'module_a.py').write_text("VALUE_A = 'a'\n")
        (module_dir / 'module_b.py').write_text("VALUE_B = 'b'\n")
        (module_dir / 'readme.txt').write_text('not a module')

        from langbot.pkg.utils import importutil

        monkeypatch.setattr(importutil, '__file__', str(tmp_path / 'pkg' / 'utils' / 'importutil.py'))
        with patch.object(importlib, 'import_module') as mock_import:
            importutil.import_dir(str(module_dir), path_prefix='test_prefix.')
            # Should call import_module for each .py file (excluding __init__.py)
            assert mock_import.call_count == 2
            mock_import.assert_has_calls(
                [call('test_prefix.test_modules.module_a'), call('test_prefix.test_modules.module_b')],
                any_order=True,
            )

    def test_skips_init_py(self, tmp_path, monkeypatch):
        """Should skip __init__.py when importing."""
        module_dir = tmp_path / 'test_modules'
        module_dir.mkdir()

        (module_dir / '__init__.py').write_text('')
        (module_dir / 'regular.py').write_text('VALUE = 1\n')

        from langbot.pkg.utils import importutil

        monkeypatch.setattr(importutil, '__file__', str(tmp_path / 'pkg' / 'utils' / 'importutil.py'))
        with patch.object(importlib, 'import_module') as mock_import:
            importutil.import_dir(str(module_dir), path_prefix='test_prefix.')
            mock_import.assert_called_once_with('test_prefix.test_modules.regular')

    def test_ignores_non_py_files(self, tmp_path, monkeypatch):
        """Should ignore non-.py files."""
        module_dir = tmp_path / 'test_modules'
        module_dir.mkdir()

        (module_dir / 'module.py').write_text('VALUE = 1\n')
        (module_dir / 'readme.txt').write_text('text')
        (module_dir / 'data.json').write_text('{}')

        from langbot.pkg.utils import importutil

        monkeypatch.setattr(importutil, '__file__', str(tmp_path / 'pkg' / 'utils' / 'importutil.py'))
        with patch.object(importlib, 'import_module') as mock_import:
            importutil.import_dir(str(module_dir), path_prefix='test_prefix.')
            mock_import.assert_called_once_with('test_prefix.test_modules.module')


class TestImportModulesInPkg:
    """Test import_modules_in_pkg function."""

    def test_imports_modules_from_package(self, tmp_path):
        """Should import all modules from a package object."""
        mock_pkg = MagicMock()
        mock_pkg.__file__ = str(tmp_path / '__init__.py')

        (tmp_path / '__init__.py').write_text('')
        (tmp_path / 'mod1.py').write_text('MOD1 = 1\n')

        from langbot.pkg.utils import importutil

        with patch.object(importutil, 'import_dir') as mock_import_dir:
            importutil.import_modules_in_pkg(mock_pkg)
            mock_import_dir.assert_called_once()
            call_path = mock_import_dir.call_args[0][0]
            assert call_path == str(tmp_path)


class TestImportModulesInPkgs:
    """Test import_modules_in_pkgs function."""

    def test_imports_from_multiple_packages(self):
        """Should call import_modules_in_pkg for each package."""
        from langbot.pkg.utils import importutil

        mock_pkg1 = MagicMock()
        mock_pkg1.__file__ = '/path/to/pkg1/__init__.py'
        mock_pkg2 = MagicMock()
        mock_pkg2.__file__ = '/path/to/pkg2/__init__.py'

        with patch.object(importutil, 'import_modules_in_pkg') as mock_import:
            importutil.import_modules_in_pkgs([mock_pkg1, mock_pkg2])
            assert mock_import.call_args_list == [call(mock_pkg1), call(mock_pkg2)]


class TestImportDotStyleDir:
    """Test import_dot_style_dir function."""

    def test_converts_dot_notation_to_path(self, tmp_path):
        """Should convert dot notation to path and import."""
        # Create structure matching the dot notation
        (tmp_path / 'my').mkdir()
        (tmp_path / 'my' / 'pkg').mkdir()
        (tmp_path / 'my' / 'pkg' / 'test').mkdir()

        from langbot.pkg.utils import importutil

        with patch.object(importutil, 'import_dir') as mock_import_dir:
            importutil.import_dot_style_dir('my.pkg.test')
            mock_import_dir.assert_called_once_with(os.path.join('my', 'pkg', 'test'))


class TestReadResourceFile:
    """Test read_resource_file function."""

    def test_reads_resource_file_content(self):
        """Should read content from a resource file."""
        from langbot.pkg.utils import importutil

        content = importutil.read_resource_file('templates/config.yaml')
        assert 'api:' in content
        assert 'edition: community' in content

    def test_raises_for_nonexistent_file(self):
        """Should raise exception for non-existent resource file."""
        from langbot.pkg.utils import importutil

        with pytest.raises((FileNotFoundError, Exception)):
            importutil.read_resource_file('nonexistent/path/file.txt')


class TestReadResourceFileBytes:
    """Test read_resource_file_bytes function."""

    def test_reads_resource_file_as_bytes(self):
        """Should read content as bytes from a resource file."""
        from langbot.pkg.utils import importutil

        content = importutil.read_resource_file_bytes('templates/config.yaml')
        assert b'api:' in content
        assert b'edition: community' in content

    def test_raises_for_nonexistent_file_bytes(self):
        """Should raise exception for non-existent resource file."""
        from langbot.pkg.utils import importutil

        with pytest.raises((FileNotFoundError, Exception)):
            importutil.read_resource_file_bytes('nonexistent/path/file.txt')


class TestListResourceFiles:
    """Test list_resource_files function."""

    def test_lists_files_in_resource_directory(self):
        """Should list files in a resource directory."""
        from langbot.pkg.utils import importutil

        files = importutil.list_resource_files('templates')
        assert 'config.yaml' in files
        assert 'default-pipeline-config.json' in files
        assert all(isinstance(file, str) for file in files)

    def test_raises_for_nonexistent_directory(self):
        """Should raise exception for non-existent directory."""
        from langbot.pkg.utils import importutil

        with pytest.raises((FileNotFoundError, Exception)):
            importutil.list_resource_files('nonexistent_directory_xyz')


if __name__ == '__main__':
    pytest.main([__file__, '-v'])