"""Utility functions for the autoimport code."""
import pathlib
import sys
from collections import OrderedDict
from typing import Generator, List, Optional, Tuple

from rope.base.project import Project

from .defs import ModuleCompiled, ModuleFile, ModuleInfo, Package, PackageType, Source


def get_package_tuple(
    package_path: pathlib.Path, project: Optional[Project] = None
) -> Optional[Package]:
    """
    Get package name and type from a path.

    Checks for common issues, such as not being a viable python module
    Returns None if not a viable package.
    """
    package_name = package_path.name
    package_type: PackageType
    if package_name.startswith(".") or package_name == "__pycache__":
        return None
    if package_name.endswith((".egg-info", ".dist-info")):
        return None
    if package_path.is_file():
        if package_name.endswith(".so"):
            package_name = package_name.split(".")[0]
            package_type = PackageType.COMPILED
        elif package_name.endswith(".pyd"):
            package_name = package_name.split(".")[0]
            package_type = PackageType.COMPILED
        elif package_name.endswith(".py"):
            package_name = package_path.stem
            package_type = PackageType.SINGLE_FILE
        else:
            return None
    else:
        package_type = PackageType.STANDARD
    package_source: Source = get_package_source(package_path, project, package_name)
    return Package(package_name, package_source, package_path, package_type)


def get_package_source(
    package: pathlib.Path, project: Optional[Project], name: str
) -> Source:
    """Detect the source of a given package. Rudimentary implementation."""
    if name in sys.builtin_module_names:
        return Source.BUILTIN
    if project is not None and project.address in str(package):
        return Source.PROJECT
    if "site-packages" in package.parts:
        return Source.SITE_PACKAGE
    if sys.version_info < (3, 10, 0):
        if str(package).startswith(sys.prefix):
            return Source.STANDARD
    else:
        if name in sys.stdlib_module_names:
            return Source.STANDARD
    return Source.UNKNOWN


def get_modname_from_path(
    modpath: pathlib.Path, package_path: pathlib.Path, add_package_name: bool = True
) -> str:
    """Get module name from a path in respect to package."""
    package_name: str = package_path.stem
    rel_path_parts = modpath.relative_to(package_path).parts
    modname = ""
    if len(rel_path_parts) > 0:
        for part in rel_path_parts[:-1]:
            modname += part
            modname += "."
        if rel_path_parts[-1] == "__init__":
            modname = modname[:-1]
        else:
            modname = modname + modpath.stem
    if add_package_name:
        modname = package_name if modname == "" else package_name + "." + modname
    else:
        assert modname != "."
    return modname


def sort_and_deduplicate(results: List[Tuple[str, int]]) -> List[str]:
    """Sort and deduplicate a list of name, source entries."""
    results = sorted(results, key=lambda y: y[-1])
    results_sorted = [name for name, source in results]
    return list(OrderedDict.fromkeys(results_sorted))


def sort_and_deduplicate_tuple(
    results: List[Tuple[str, str, int]]
) -> List[Tuple[str, str]]:
    """Sort and deduplicate a list of name, module, source entries."""
    results = sorted(results, key=lambda y: y[-1])
    results_sorted = [result[:-1] for result in results]
    return list(OrderedDict.fromkeys(results_sorted))


def should_parse(path: pathlib.Path, underlined: bool) -> bool:
    if underlined:
        return True
    for part in path.parts:
        if part.startswith("_"):
            return False
    return True


def get_files(
    package: Package, underlined: bool = False
) -> Generator[ModuleInfo, None, None]:
    """Find all files to parse in a given path using __init__.py."""
    if package.type in (PackageType.COMPILED, PackageType.BUILTIN):
        if package.source in (Source.STANDARD, Source.BUILTIN):
            yield ModuleCompiled(None, package.name, underlined, True)
    elif package.type == PackageType.SINGLE_FILE:
        assert package.path
        assert package.path.suffix == ".py"
        yield ModuleFile(package.path, package.path.stem, underlined, False)
    else:
        assert package.path
        for file in package.path.glob("*.py"):
            if file.name == "__init__.py":
                yield ModuleFile(
                    file,
                    get_modname_from_path(file.parent, package.path),
                    underlined,
                    True,
                )
            elif should_parse(file, underlined):
                yield ModuleFile(
                    file, get_modname_from_path(file, package.path), underlined, False
                )
