from __future__ import annotations

import logging
from collections import defaultdict
from dataclasses import dataclass
from pathlib import Path
from typing import Any, ClassVar, Iterator, Optional, Type

from dcs.unittype import VehicleType
from dcs.vehicles import vehicle_map

from game.data.units import UnitClass
from game.dcs.unittype import UnitType


@dataclass
class SkynetProperties:
    can_engage_harm: Optional[str] = None
    can_engage_air_weapon: Optional[str] = None
    go_live_range_in_percent: Optional[str] = None
    engagement_zone: Optional[str] = None
    autonomous_behaviour: Optional[str] = None
    harm_detection_chance: Optional[str] = None

    @classmethod
    def from_data(cls, data: dict[str, Any]) -> SkynetProperties:
        props = SkynetProperties()
        if "can_engage_harm" in data:
            props.can_engage_harm = str(data["can_engage_harm"]).lower()
        if "can_engage_air_weapon" in data:
            props.can_engage_air_weapon = str(data["can_engage_air_weapon"]).lower()
        if "go_live_range_in_percent" in data:
            props.go_live_range_in_percent = str(data["go_live_range_in_percent"])
        if "engagement_zone" in data:
            props.engagement_zone = str(data["engagement_zone"])
        if "autonomous_behaviour" in data:
            props.autonomous_behaviour = str(data["autonomous_behaviour"])
        if "harm_detection_chance" in data:
            props.harm_detection_chance = str(data["harm_detection_chance"])
        return props

    def to_dict(self) -> dict[str, str]:
        properties: dict[str, str] = {}
        for key, value in self.__dict__.items():
            if value is not None:
                properties[key] = value
        return properties

    def __hash__(self) -> int:
        return hash(id(self))


@dataclass(frozen=True)
class GroundUnitType(UnitType[Type[VehicleType]]):
    spawn_weight: int
    skynet_properties: SkynetProperties

    # Defines if we should place the ground unit with an inverted heading.
    # Some units like few Launchers have to be placed backwards to be able to fire.
    reversed_heading: bool = False

    _by_name: ClassVar[dict[str, GroundUnitType]] = {}
    _by_unit_type: ClassVar[
        dict[type[VehicleType], list[GroundUnitType]]
    ] = defaultdict(list)

    def __setstate__(self, state: dict[str, Any]) -> None:
        # Save compat: the `name` field has been renamed `variant_id`.
        if "name" in state:
            state["variant_id"] = state.pop("name")

        # iron-dome migration to IDF assets
        if state["variant_id"] in [
            "(IDF Mods Project) BM-21 Grad 122mm",
            "(IDF Mods Project) Urgan BM-27 220mm",
            "(IDF Mods Project) 9A52 Smerch CM 300mm",
        ]:
            state["variant_id"] = "M109A6 Paladin"
        elif state["variant_id"] == "Iron Dome ELM-2048 MMR":
            state["variant_id"] = "ELM-2084MMR AD Rotating Mode"

        # Update any existing models with new data on load.
        updated = GroundUnitType.named(state["variant_id"])
        state.update(updated.__dict__)
        self.__dict__.update(state)

    @classmethod
    def register(cls, unit_type: GroundUnitType) -> None:
        cls._by_name[unit_type.variant_id] = unit_type
        cls._by_unit_type[unit_type.dcs_unit_type].append(unit_type)

    @classmethod
    def named(cls, name: str) -> GroundUnitType:
        if not cls._loaded:
            cls._load_all()
        return cls._by_name[name]

    @classmethod
    def for_dcs_type(cls, dcs_unit_type: Type[VehicleType]) -> Iterator[GroundUnitType]:
        if not cls._loaded:
            cls._load_all()
        yield from cls._by_unit_type[dcs_unit_type]

    @staticmethod
    def each_dcs_type() -> Iterator[Type[VehicleType]]:
        yield from vehicle_map.values()

    @classmethod
    def _data_directory(cls) -> Path:
        return Path("resources/units/ground_units")

    @classmethod
    def _variant_from_dict(
        cls, vehicle: Type[VehicleType], variant_id: str, data: dict[str, Any]
    ) -> GroundUnitType:
        try:
            introduction = data["introduced"]
            if introduction is None:
                introduction = "N/A"
        except KeyError:
            introduction = "No data."

        class_name = data.get("class")
        if class_name is None:
            logging.warning(f"{vehicle.id} has no class")
            unit_class = UnitClass.UNKNOWN
        else:
            unit_class = UnitClass(class_name)

        display_name = data.get("display_name", variant_id)
        return GroundUnitType(
            dcs_unit_type=vehicle,
            unit_class=unit_class,
            spawn_weight=data.get("spawn_weight", 0),
            variant_id=variant_id,
            display_name=display_name,
            description=data.get(
                "description",
                f"No data. <a href=\"https://google.com/search?q=DCS+{display_name.replace(' ', '+')}\"><span style=\"color:#FFFFFF\">Google {display_name}</span></a>",
            ),
            year_introduced=introduction,
            country_of_origin=data.get("origin", "No data."),
            manufacturer=data.get("manufacturer", "No data."),
            role=data.get("role", "No data."),
            price=data.get("price", 1),
            skynet_properties=SkynetProperties.from_data(
                data.get("skynet_properties", {})
            ),
            reversed_heading=data.get("reversed_heading", False),
        )