"""统一的动作表：HTTP、WebSocket、命令行、机器人都走这一份映射。

为什么要有这一层
----------------
引擎（``farm.engine.FarmEngine``）提供的是**方法**，但外部调用者（AI Agent、
脚本、网页）手里拿到的只有字符串动作名 + 参数字典。如果让每个入口各自写一遍
``if action == "plant"`` 的分发，规则就会散落在三四个文件里，迟早出现
"HTTP 能做、WS 不能做" 这种不一致。

所以这里集中定义：动作名 → 参数规格 → 引擎调用 → 返回结果。
新增一个玩法动作，只需要在这张表里加一行。
"""

from __future__ import annotations

from collections.abc import Callable
from typing import Any

from .. import config
from ..engine import FarmEngine, GameError


class Param:
    """一个动作参数的规格说明（同时用于校验与自动生成给 AI 的文档）。"""

    __slots__ = ("default", "desc", "kind", "name", "required")

    def __init__(
        self, name: str, kind: str, required: bool = True, default: Any = None, desc: str = ""
    ) -> None:
        self.name = name
        self.kind = kind  # "int" / "str" / "bool"
        self.required = required
        self.default = default
        self.desc = desc

    def coerce(self, raw: Any) -> Any:
        """把外部传来的值转成期望类型，失败时抛出带 code 的业务异常。"""
        if self.kind == "bool":
            if isinstance(raw, bool):
                return raw
            if isinstance(raw, str) and raw.lower() in ("true", "false", "1", "0"):
                return raw.lower() in ("true", "1")
            if isinstance(raw, int):
                return bool(raw)
            raise GameError("bad_param", f"参数 {self.name} 需要布尔值，收到 {raw!r}")
        if self.kind == "int":
            if isinstance(raw, bool):
                raise GameError("bad_param", f"参数 {self.name} 需要整数，收到布尔值")
            if isinstance(raw, int):
                return raw
            if isinstance(raw, float) and raw.is_integer():
                return int(raw)
            if isinstance(raw, str) and raw.strip().lstrip("+-").isdigit():
                return int(raw.strip())
            raise GameError("bad_param", f"参数 {self.name} 需要整数，收到 {raw!r}")
        if self.kind == "str":
            if isinstance(raw, (str, int, float)):
                return str(raw)
            raise GameError("bad_param", f"参数 {self.name} 需要字符串，收到 {raw!r}")
        return raw

    def to_dict(self) -> dict[str, Any]:
        return {
            "name": self.name,
            "type": self.kind,
            "required": self.required,
            "default": self.default,
            "desc": self.desc,
        }


class Action:
    """一个可执行动作。"""

    __slots__ = ("handler", "name", "params", "realtime", "summary")

    def __init__(
        self,
        name: str,
        summary: str,
        params: list[Param],
        handler: Callable[[FarmEngine, dict[str, Any]], dict[str, Any]],
        realtime: bool = True,
    ) -> None:
        self.name = name
        self.summary = summary
        self.params = params
        self.handler = handler
        self.realtime = realtime

    def to_dict(self) -> dict[str, Any]:
        return {
            "action": self.name,
            "summary": self.summary,
            "params": [p.to_dict() for p in self.params],
        }


# ---------------------------------------------------------------------- 处理器
def _harvest_all(engine: FarmEngine, _params: dict[str, Any]) -> dict[str, Any]:
    """收获所有成熟作物。逐块调用引擎，个别地块失败不影响其它地块。"""
    total_gold = 0
    total_units = 0
    plots: list[int] = []
    errors: list[str] = []
    # 复制列表：harvest 会修改 state.plots 中元素的内容，但不会增删元素
    for plot in list(engine.state.plots):
        if not plot.is_ripe:
            continue
        try:
            result = engine.harvest(plot.index + 1)
        except GameError as exc:
            errors.append(f"{plot.index + 1}号地：{exc.message}")
            continue
        total_gold += int(result.get("earned", 0))
        total_units += int(result.get("quantity", 0))
        plots.append(plot.index + 1)

    if not plots and not errors:
        raise GameError("nothing_to_harvest", "当前没有成熟的作物可以收获")
    return {
        "message": f"收获 {len(plots)} 块地共 {total_units} 份作物，+{total_gold} 金币",
        "plots": plots,
        "quantity": total_units,
        "earned": total_gold,
        "errors": errors,
    }


def _save(engine: FarmEngine, _params: dict[str, Any]) -> dict[str, Any]:
    return engine.save()


def _reset(engine: FarmEngine, _params: dict[str, Any]) -> dict[str, Any]:
    return engine.reset()


def _pause(engine: FarmEngine, params: dict[str, Any]) -> dict[str, Any]:
    value = params.get("paused")
    return engine.pause(value if isinstance(value, bool) else None)


# ---------------------------------------------------------------------- 动作表
ACTIONS: dict[str, Action] = {}


def _register(action: Action) -> None:
    ACTIONS[action.name] = action


_register(
    Action(
        "plant",
        "在指定地块播种",
        [
            Param("plot", "int", True, None, "地块编号，从 1 开始"),
            Param("crop", "str", True, None, "作物标识，如 wheat"),
        ],
        lambda e, p: e.plant(p["plot"], p["crop"]),
    )
)

_register(
    Action(
        "water",
        "给指定地块浇水（补满水分）",
        [
            Param("plot", "int", True, None, "地块编号，从 1 开始"),
        ],
        lambda e, p: e.water(p["plot"]),
    )
)

_register(
    Action(
        "harvest",
        "收获指定地块的成熟作物",
        [
            Param("plot", "int", True, None, "地块编号，从 1 开始"),
        ],
        lambda e, p: e.harvest(p["plot"]),
    )
)

_register(Action("harvest_all", "一键收获所有成熟作物", [], _harvest_all))

_register(
    Action(
        "buy_animal",
        "购买牲畜",
        [
            Param("kind", "str", True, None, "牲畜标识：chicken / sheep / cow"),
        ],
        lambda e, p: e.buy_animal(p["kind"]),
    )
)

_register(
    Action(
        "feed",
        "喂食指定牲畜",
        [
            Param("animal_id", "int", True, None, "牲畜编号（state.animals[].id）"),
            Param("quantity", "int", False, None, "喂食份数，默认按需求；多喂无益"),
        ],
        lambda e, p: e.feed(p["animal_id"], p.get("quantity")),
    )
)

_register(
    Action(
        "collect",
        "收取牲畜的产出并自动出售",
        [
            Param("animal_id", "int", True, None, "牲畜编号"),
        ],
        lambda e, p: e.collect(p["animal_id"]),
    )
)

_register(
    Action(
        "buy_feed",
        "购买饲料",
        [
            Param("quantity", "int", False, config.FEED_BULK, f"份数，默认 {config.FEED_BULK}"),
        ],
        lambda e, p: e.buy_feed(p.get("quantity", config.FEED_BULK)),
    )
)

_register(Action("buy_plot", "花钱开垦一块新土地", [], lambda e, p: e.buy_plot()))

_register(Action("sleep", "主动推进一天（有冷却）", [], lambda e, p: e.sleep()))

_register(
    Action(
        "pause",
        "暂停或恢复自动推进时间",
        [
            Param("paused", "bool", False, None, "true 暂停 / false 恢复；省略则反转当前状态"),
        ],
        _pause,
    )
)

_register(Action("save", "把当前农场写入存档文件", [], _save))

_register(Action("reset", "重置农场，从头开始经营", [], _reset))


def action_names() -> list[str]:
    return sorted(ACTIONS)


def describe_actions() -> list[dict[str, Any]]:
    return [ACTIONS[name].to_dict() for name in action_names()]


def run_action(engine: FarmEngine, name: Any, params: Any = None) -> dict[str, Any]:
    """校验参数并执行动作。

    这是所有入口的**唯一**执行通道，因此输入校验只需要在这里做一次。
    """
    if not isinstance(name, str) or not name.strip():
        raise GameError("bad_param", "缺少动作名 action")
    key = name.strip().lower()
    action = ACTIONS.get(key)
    if action is None:
        raise GameError(
            "unknown_action",
            f"未知动作 {name!r}，可用动作：{'、'.join(action_names())}",
        )
    if params is None:
        params = {}
    # params 来自外部 JSON，类型标注是 Any 而不是 dict——这里的检查是**真的**校验，
    # 不是多余防御（`params` 完全可能就是数组或字符串）
    if not isinstance(params, dict):
        raise GameError("bad_param", "params 必须是对象")

    known = {p.name for p in action.params}
    unknown = [k for k in params if k not in known]
    if unknown:
        allowed = "、".join(sorted(known)) or "无"
        raise GameError(
            "bad_param",
            f"动作 {key} 不认识参数 {'、'.join(unknown)}（可用：{allowed}）",
        )

    clean: dict[str, Any] = {}
    for spec in action.params:
        if spec.name in params and params[spec.name] is not None:
            clean[spec.name] = spec.coerce(params[spec.name])
        elif spec.required:
            raise GameError("missing_param", f"动作 {key} 缺少必需参数 {spec.name}")
        elif spec.default is not None:
            clean[spec.name] = spec.default

    # handler 声明返回 dict，但这里是所有入口的唯一执行通道，仍然兜一层：
    # 万一以后有 handler 返回了别的类型，也不会污染接口格式
    raw: Any = action.handler(engine, clean)
    result: dict[str, Any] = raw if isinstance(raw, dict) else {"message": str(raw)}
    result.setdefault("ok", True)
    result["action"] = key
    return result