"""Path utilities for the Auto README Generator."""

import os
import re
from pathlib import Path
from typing import Optional


class PathUtils:
    """Utility class for path operations."""

    IGNORED_DIRS = {
        "__pycache__",
        ".git",
        ".svn",
        ".hg",
        "__MACOSX",
        ".DS_Store",
        "node_modules",
        ".venv",
        "venv",
        "ENV",
        "env",
        ".tox",
        ".nox",
        "build",
        "dist",
        "target",
        ".idea",
        ".vscode",
    }

    IGNORED_FILES = {
        ".DS_Store",
        ".gitignore",
        ".gitattributes",
        ".gitmodules",
    }

    SOURCE_EXTENSIONS = {
        ".py",
        ".js",
        ".ts",
        ".jsx",
        ".tsx",
        ".go",
        ".rs",
        ".java",
        ".c",
        ".cpp",
        ".h",
        ".hpp",
        ".rb",
        ".php",
        ".swift",
        ".kt",
        ".scala",
    }

    CONFIG_EXTENSIONS = {".json", ".yaml", ".yml", ".toml", ".cfg", ".ini", ".conf"}

    DOCUMENTATION_EXTENSIONS = {".md", ".rst", ".txt", ".adoc"}

    TEST_PATTERNS = [
        re.compile(r"^test_"),
        re.compile(r"_test\.py$"),
        re.compile(r"^tests?\/"),
        re.compile(r"spec\."),
        re.compile(r"\.test\."),
        re.compile(r"\.tests\."),
    ]

    @classmethod
    def normalize_path(cls, path: str | Path) -> Path:
        """Normalize a path to absolute form."""
        return Path(path).resolve()

    @classmethod
    def is_ignored_dir(cls, path: Path) -> bool:
        """Check if a directory should be ignored."""
        return path.name in cls.IGNORED_DIRS or path.name.startswith(".")

    @classmethod
    def is_ignored_file(cls, path: Path) -> bool:
        """Check if a file should be ignored."""
        return path.name in cls.IGNORED_FILES

    @classmethod
    def is_source_file(cls, path: Path) -> bool:
        """Check if a file is a source code file."""
        return path.suffix in cls.SOURCE_EXTENSIONS

    @classmethod
    def is_config_file(cls, path: Path) -> bool:
        """Check if a file is a configuration file."""
        return path.suffix in cls.CONFIG_EXTENSIONS

    @classmethod
    def is_documentation_file(cls, path: Path) -> bool:
        """Check if a file is a documentation file."""
        return path.suffix in cls.DOCUMENTATION_EXTENSIONS

    @classmethod
    def is_test_file(cls, path: Path) -> bool:
        """Check if a file is a test file."""
        for pattern in cls.TEST_PATTERNS:
            if pattern.search(str(path)):
                return True
        return False

    @classmethod
    def get_relative_path(cls, path: Path, base: Path) -> Path:
        """Get relative path from base directory."""
        try:
            return path.relative_to(base)
        except ValueError:
            return path

    @classmethod
    def is_hidden(cls, path: Path) -> bool:
        """Check if a path is hidden (starts with dot)."""
        return path.name.startswith(".")

    @classmethod
    def detect_project_root(cls, path: Path) -> Optional[Path]:
        """Detect project root by looking for marker files."""
        markers = [
            "pyproject.toml",
            "package.json",
            "go.mod",
            "Cargo.toml",
            "setup.py",
            "setup.cfg",
            "requirements.txt",
            "Pipfile",
            "pom.xml",
            "build.gradle",
        ]

        current = cls.normalize_path(path)
        for _ in range(50):
            for marker in markers:
                if (current / marker).exists():
                    return current
            if current.parent == current:
                break
            current = current.parent

        return None

    @classmethod
    def is_file_empty(cls, path: Path) -> bool:
        """Check if a file is empty."""
        try:
            return os.path.getsize(path) == 0
        except OSError:
            return True

    @classmethod
    def get_file_size(cls, path: Path) -> int:
        """Get file size in bytes."""
        try:
            return os.path.getsize(path)
        except OSError:
            return 0

    @classmethod
    def count_lines(cls, path: Path) -> int:
        """Count lines in a file."""
        try:
            with open(path, "r", encoding="utf-8", errors="ignore") as f:
                return sum(1 for _ in f)
        except OSError:
            return 0

    @classmethod
    def safe_read(cls, path: Path, max_size: int = 1024 * 1024) -> Optional[str]:
        """Safely read file contents with size limit."""
        try:
            if cls.get_file_size(path) > max_size:
                return None
            with open(path, "r", encoding="utf-8", errors="ignore") as f:
                return f.read()
        except OSError:
            return None


def normalize_path(path: str | Path) -> Path:
    """Normalize a path to absolute form."""
    return PathUtils.normalize_path(path)