import shutil
from pathlib import Path
from typing import TYPE_CHECKING, NamedTuple

from dotenv import dotenv_values

if TYPE_CHECKING:
    from pytest_abra.dir_manager import DirManager
    from pytest_abra.runner import Runner


class EnvFile(NamedTuple):
    env_path: Path
    env_config: dict[str, str]
    env_type: str

    def __repr__(self) -> str:
        return f"EnvFile(type={self.env_type})"


class DependencyRule(NamedTuple):
    child: str
    dependency: str


class EnvManager:
    def __init__(self, env_paths: list[Path], RUNNER_DICT: dict[str, type["Runner"]]):
        self.env_files: list[EnvFile] = self._get_env_files(env_paths)
        self.dependency_rules: list[DependencyRule] = self._get_dependency_rules(self.env_files, RUNNER_DICT)
        self.env_files = self.sort_env_files_by_rule(self.env_files, self.dependency_rules)

    @staticmethod
    def _get_env_files(env_paths: list[Path]) -> list[EnvFile]:
        """Returns a list of EnvFile objects created from the given env files"""
        env_files: list[EnvFile] = []
        for env_path in env_paths:
            assert env_path.is_file(), f"the env file {env_path} does not exist"
            config: dict[str, str] = dotenv_values(env_path)  # type: ignore
            assert "TYPE" in config, f"the env file {env_path} does not specify the required TYPE key."
            env_type = config["TYPE"]
            env_files.append(EnvFile(env_path=env_path, env_config=config, env_type=env_type))
        return env_files

    @staticmethod
    def _get_dependency_rules(env_files: list[EnvFile], RUNNER_DICT: dict[str, type["Runner"]]) -> list[DependencyRule]:
        dependency_rules: list[DependencyRule] = []
        for env_file in env_files:
            child_runner_class = RUNNER_DICT[env_file.env_type]
            for dependency in child_runner_class.dependencies:
                dependency_rule = DependencyRule(child=child_runner_class.env_type, dependency=dependency)
                dependency_rules.append(dependency_rule)
        return dependency_rules

    @staticmethod
    def _get_indices_by_string(in_list: list[EnvFile], string: str) -> list[int]:
        """returns all indices of items in in_list, where item.env_type matches string"""
        return [index for index, element in enumerate(in_list) if element.env_type == string]

    @staticmethod
    def _swap_item_with_previous(in_list: list[EnvFile], index: int):
        """swaps item at index N with item at index N-1"""
        assert index > 0, "cannot swap with negative index"
        in_list[index], in_list[index - 1] = in_list[index - 1], in_list[index]

    @classmethod
    def is_rule_satisfied(cls, env_list: list[EnvFile], rule: DependencyRule, swap=False) -> bool:
        """returns if the ordering in in_list is compliant with the given rule

        if swap=True, some reordering will happen in case of a violated rule"""

        child_indices = cls._get_indices_by_string(env_list, rule.child)
        parent_indices = cls._get_indices_by_string(env_list, rule.dependency)
        for child_index in child_indices:
            for parent_index in parent_indices:
                if not parent_index < child_index:
                    if swap:
                        cls._swap_item_with_previous(env_list, parent_index)
                    return False
        return True

    @classmethod
    def sort_env_files_by_rule(cls, env_list: list[EnvFile], rules: list[DependencyRule]) -> list[EnvFile]:
        out_list = env_list.copy()

        for _ in range(10_000):
            rule_satisfied: list[bool] = []
            for rule in rules:
                rule_satisfied.append(cls.is_rule_satisfied(out_list, rule, swap=True))

            if all(rule_satisfied):
                return out_list
        raise ValueError(
            "Could not resolve test order. This is possibly due to a circular dependency (a on b, b on c, c on a)"
        )

    def copy_env_files(self, DIR: "DirManager") -> None:
        """Copies all env files to STATES/env_files. Files will be renamed to
        <index>-<env_type>-<original_name>
        00-authentik-login.test.dev.local-it.cloud.env"""

        for index, env_file in enumerate(self.env_files):
            file_name = "-".join([str(index).zfill(2), env_file.env_type, env_file.env_path.name])
            shutil.copy(env_file.env_path, DIR.ENV_FILES / file_name)