#!/usr/bin/env python3
"""
Check pandas required and optional dependencies are synced across:

ci/deps/actions-.*-minimum_versions.yaml
pandas/compat/_optional.py
setup.cfg

TODO: doc/source/getting_started/install.rst

This is meant to be run as a pre-commit hook - to run it manually, you can do:

    pre-commit run validate-min-versions-in-sync --all-files
"""
from __future__ import annotations

import pathlib
import sys

import yaml

if sys.version_info >= (3, 11):
    import tomllib
else:
    import tomli as tomllib

from typing import Any

from scripts.generate_pip_deps_from_conda import CONDA_TO_PIP

DOC_PATH = pathlib.Path("doc/source/getting_started/install.rst").resolve()
CI_PATH = next(
    pathlib.Path("ci/deps").absolute().glob("actions-*-minimum_versions.yaml")
)
CODE_PATH = pathlib.Path("pandas/compat/_optional.py").resolve()
SETUP_PATH = pathlib.Path("pyproject.toml").resolve()
YAML_PATH = pathlib.Path("ci/deps")
ENV_PATH = pathlib.Path("environment.yml")
EXCLUDE_DEPS = {"tzdata", "blosc", "pandas-gbq", "pyqt", "pyqt5"}
EXCLUSION_LIST = frozenset(["python=3.8[build=*_pypy]"])
# pandas package is not available
# in pre-commit environment
sys.path.append("pandas/compat")
sys.path.append("pandas/util")
import _exceptions
import version

sys.modules["pandas.util.version"] = version
sys.modules["pandas.util._exceptions"] = _exceptions
import _optional


def pin_min_versions_to_ci_deps() -> int:
    """
    Pin minimum versions to CI dependencies.

    Pip dependencies are not pinned.
    """
    all_yaml_files = list(YAML_PATH.iterdir())
    all_yaml_files.append(ENV_PATH)
    toml_dependencies = {}
    with open(SETUP_PATH, "rb") as toml_f:
        toml_dependencies = tomllib.load(toml_f)
    ret = 0
    for curr_file in all_yaml_files:
        with open(curr_file, encoding="utf-8") as yaml_f:
            yaml_start_data = yaml_f.read()
        yaml_file = yaml.safe_load(yaml_start_data)
        yaml_dependencies = yaml_file["dependencies"]
        yaml_map = get_yaml_map_from(yaml_dependencies)
        toml_map = get_toml_map_from(toml_dependencies)
        yaml_result_data = pin_min_versions_to_yaml_file(
            yaml_map, toml_map, yaml_start_data
        )
        if yaml_result_data != yaml_start_data:
            with open(curr_file, "w", encoding="utf-8") as f:
                f.write(yaml_result_data)
            ret |= 1
    return ret


def get_toml_map_from(toml_dic: dict[str, Any]) -> dict[str, str]:
    toml_deps = {}
    toml_dependencies = set(toml_dic["project"]["optional-dependencies"]["all"])
    for dependency in toml_dependencies:
        toml_package, toml_version = dependency.strip().split(">=")
        toml_deps[toml_package] = toml_version
    return toml_deps


def get_operator_from(dependency: str) -> str | None:
    if "<=" in dependency:
        operator = "<="
    elif ">=" in dependency:
        operator = ">="
    elif "=" in dependency:
        operator = "="
    elif ">" in dependency:
        operator = ">"
    elif "<" in dependency:
        operator = "<"
    else:
        operator = None
    return operator


def get_yaml_map_from(
    yaml_dic: list[str | dict[str, list[str]]]
) -> dict[str, list[str] | None]:
    yaml_map: dict[str, list[str] | None] = {}
    for dependency in yaml_dic:
        if (
            isinstance(dependency, dict)
            or dependency in EXCLUSION_LIST
            or dependency in yaml_map
        ):
            continue
        search_text = str(dependency)
        operator = get_operator_from(search_text)
        if "," in dependency:
            yaml_dependency, yaml_version1 = search_text.split(",")
            operator = get_operator_from(yaml_dependency)
            assert operator is not None
            yaml_package, yaml_version2 = yaml_dependency.split(operator)
            yaml_version2 = operator + yaml_version2
            yaml_map[yaml_package] = [yaml_version1, yaml_version2]
        elif "[build=*_pypy]" in dependency:
            search_text = search_text.replace("[build=*_pypy]", "")
            yaml_package, yaml_version = search_text.split(operator)
            yaml_version = operator + yaml_version
            yaml_map[yaml_package] = [yaml_version]
        elif operator is not None:
            yaml_package, yaml_version = search_text.split(operator)
            yaml_version = operator + yaml_version
            yaml_map[yaml_package] = [yaml_version]
        else:
            yaml_package, yaml_version = search_text.strip(), None
            yaml_map[yaml_package] = yaml_version
    return yaml_map


def clean_version_list(
    yaml_versions: list[str], toml_version: version.Version
) -> list[str]:
    for i in range(len(yaml_versions)):
        yaml_version = yaml_versions[i]
        operator = get_operator_from(yaml_version)
        assert operator is not None
        if "<=" in operator or ">=" in operator:
            yaml_version = yaml_version[2:]
        else:
            yaml_version = yaml_version[1:]
        yaml_version = version.parse(yaml_version)
        if yaml_version < toml_version:
            yaml_versions[i] = "-" + str(yaml_version)
        elif yaml_version >= toml_version:
            if ">" in operator:
                yaml_versions[i] = "-" + str(yaml_version)
    return yaml_versions


def pin_min_versions_to_yaml_file(
    yaml_map: dict[str, list[str] | None], toml_map: dict[str, str], yaml_file_data: str
) -> str:
    data = yaml_file_data
    for yaml_package, yaml_versions in yaml_map.items():
        if yaml_package in EXCLUSION_LIST:
            continue
        old_dep = yaml_package
        if yaml_versions is not None:
            old_dep = old_dep + ", ".join(yaml_versions)
        if CONDA_TO_PIP.get(yaml_package, yaml_package) in toml_map:
            min_dep = toml_map[CONDA_TO_PIP.get(yaml_package, yaml_package)]
        elif yaml_package in toml_map:
            min_dep = toml_map[yaml_package]
        else:
            continue
        if yaml_versions is None:
            new_dep = old_dep + ">=" + min_dep
            data = data.replace(old_dep, new_dep, 1)
            continue
        toml_version = version.parse(min_dep)
        yaml_versions_list = clean_version_list(yaml_versions, toml_version)
        cleaned_yaml_versions = [x for x in yaml_versions_list if "-" not in x]
        new_dep = yaml_package
        for clean_yaml_version in cleaned_yaml_versions:
            new_dep += clean_yaml_version + ", "
        operator = get_operator_from(new_dep)
        if operator != "=":
            new_dep += ">=" + min_dep
        else:
            new_dep = new_dep[:-2]
        data = data.replace(old_dep, new_dep)
    return data


def get_versions_from_code() -> dict[str, str]:
    """Min versions for checking within pandas code."""
    install_map = _optional.INSTALL_MAPPING
    inverse_install_map = {v: k for k, v in install_map.items()}
    versions = _optional.VERSIONS
    for item in EXCLUDE_DEPS:
        item = inverse_install_map.get(item, item)
        versions.pop(item, None)
    return {install_map.get(k, k).casefold(): v for k, v in versions.items()}


def get_versions_from_ci(content: list[str]) -> tuple[dict[str, str], dict[str, str]]:
    """Min versions in CI job for testing all optional dependencies."""
    # Don't parse with pyyaml because it ignores comments we're looking for
    seen_required = False
    seen_optional = False
    seen_test = False
    required_deps = {}
    optional_deps = {}
    for line in content:
        if "# test dependencies" in line:
            seen_test = True
        elif seen_test and "- pytest>=" in line:
            # Only grab pytest
            package, version = line.strip().split(">=")
            package = package[2:]
            optional_deps[package.casefold()] = version
        elif "# required dependencies" in line:
            seen_required = True
        elif "# optional dependencies" in line:
            seen_optional = True
        elif "- pip:" in line:
            continue
        elif seen_required and line.strip():
            if "==" in line:
                package, version = line.strip().split("==", maxsplit=1)
            else:
                package, version = line.strip().split("=", maxsplit=1)
            package = package.split()[-1]
            if package in EXCLUDE_DEPS:
                continue
            if not seen_optional:
                required_deps[package.casefold()] = version
            else:
                optional_deps[package.casefold()] = version
    return required_deps, optional_deps


def get_versions_from_toml() -> dict[str, str]:
    """Min versions in pyproject.toml for pip install pandas[extra]."""
    install_map = _optional.INSTALL_MAPPING
    optional_dependencies = {}
    with open(SETUP_PATH, "rb") as pyproject_f:
        pyproject_toml = tomllib.load(pyproject_f)
        opt_deps = pyproject_toml["project"]["optional-dependencies"]
        dependencies = set(opt_deps["all"])

        # remove pytest plugin dependencies
        pytest_plugins = {dep for dep in opt_deps["test"] if dep.startswith("pytest-")}
        dependencies = dependencies.difference(pytest_plugins)

    for dependency in dependencies:
        package, version = dependency.strip().split(">=")
        optional_dependencies[install_map.get(package, package).casefold()] = version

    for item in EXCLUDE_DEPS:
        optional_dependencies.pop(item, None)
    return optional_dependencies


def main() -> int:
    ret = 0
    ret |= pin_min_versions_to_ci_deps()
    with open(CI_PATH, encoding="utf-8") as f:
        _, ci_optional = get_versions_from_ci(f.readlines())
    code_optional = get_versions_from_code()
    setup_optional = get_versions_from_toml()

    diff = (ci_optional.items() | code_optional.items() | setup_optional.items()) - (
        ci_optional.items() & code_optional.items() & setup_optional.items()
    )

    if diff:
        packages = {package for package, _ in diff}
        out = sys.stdout
        out.write(
            f"The follow minimum version differences were found between  "
            f"{CI_PATH}, {CODE_PATH} AND {SETUP_PATH}. "
            f"Please ensure these are aligned: \n\n"
        )

        for package in packages:
            out.write(
                f"{package}\n"
                f"{CI_PATH}: {ci_optional.get(package, 'Not specified')}\n"
                f"{CODE_PATH}: {code_optional.get(package, 'Not specified')}\n"
                f"{SETUP_PATH}: {setup_optional.get(package, 'Not specified')}\n\n"
            )
        ret |= 1
    return ret


if __name__ == "__main__":
    sys.exit(main())