import pytest
from pathlib import Path
from codechunk.core.dependency import DependencyAnalyzer, DependencyNode
from codechunk.core.chunking import ParsedChunk, ChunkMetadata


class TestDependencyAnalyzer:
    """Tests for DependencyAnalyzer."""

    def test_analyze_dependencies_basic(self, tmp_path):
        """Test basic dependency analysis."""
        main_code = '''
import os
import json

def main():
    pass
'''
        utils_code = '''
from typing import List

def helper():
    pass
'''

        (tmp_path / "main.py").write_text(main_code)
        (tmp_path / "utils.py").write_text(utils_code)

        from codechunk.core.parser import CodeParser
        parser = CodeParser()
        parser.discover_files(tmp_path, ["*.py"], [])
        chunks = parser.parse_all()

        analyzer = DependencyAnalyzer()
        graph = analyzer.analyze_dependencies(chunks, parser.files)

        assert len(graph) >= 2

    def test_get_essential_chunks(self):
        """Test getting essential chunks including dependencies."""
        analyzer = DependencyAnalyzer()

        analyzer.dependency_graph = {
            "main": DependencyNode(
                chunk_name="main",
                file_path=Path("main.py"),
                module_name="main",
                dependencies={"utils", "helper"}
            ),
            "utils": DependencyNode(
                chunk_name="utils",
                file_path=Path("utils.py"),
                module_name="utils",
                dependencies={"helper"}
            ),
            "helper": DependencyNode(
                chunk_name="helper",
                file_path=Path("helper.py"),
                module_name="helper",
                dependencies=set()
            ),
        }

        essential = analyzer.get_essential_chunks(["main"])

        assert "main" in essential
        assert "utils" in essential
        assert "helper" in essential

    def test_empty_project(self):
        """Test dependency analysis with no chunks."""
        analyzer = DependencyAnalyzer()
        graph = analyzer.analyze_dependencies([], [])

        assert len(graph) == 0


class TestDependencyNode:
    """Tests for DependencyNode dataclass."""

    def test_dependency_node_creation(self):
        """Test creating a dependency node."""
        node = DependencyNode(
            chunk_name="test",
            file_path=Path("test.py"),
            module_name="test",
            dependencies={"dep1", "dep2"},
            dependents={"parent"}
        )

        assert node.chunk_name == "test"
        assert node.dependencies == {"dep1", "dep2"}