import type { MediaKind, PublicOrganizationRecord, SlotPosition } from "@umt/contracts";
import type { ComponentType } from "react";

// 前端插槽(ADR-006):功能模块按位置注册组件,页面在挂载点渲染。默认直接显示,不做开关(内部用,做了就是要用)。
// 注册写在 app/features/*.tsx,由 app/features/index.ts 汇总;挂载点组件在 components/slots/slot-mounts.tsx。
// 位置分两类:
// - 动作类(entity.actions、organize.record.actions):一个按钮 / 菜单项,点了打开功能自己的对话框;
// - 面板类(entity.panels、settings.sections、sidebar.entry):直接渲染组件。

/** 插槽里拿到的作品(作品页) */
export interface SlotEntity {
  id: string;
  title: string;
  kind: MediaKind;
  status: string;
}

export interface SlotProps {
  "sidebar.entry": Record<string, never>;
  "entity.actions": { entity: SlotEntity };
  "entity.panels": { entity: SlotEntity };
  "organize.record.actions": { record: PublicOrganizationRecord };
  "settings.sections": Record<string, never>;
}

export type ActionPosition = "entity.actions" | "organize.record.actions";
export type PanelPosition = Exclude<SlotPosition, ActionPosition>;

interface SlotBase {
  /** 全局唯一,建议 <功能>.<位置> */
  id: string;
  /** 所属功能(contracts FEATURES 的 id) */
  feature: string;
  /** 越小越靠前,缺省 100;同序按注册顺序 */
  order?: number;
}

export interface ActionSlot<P extends ActionPosition = ActionPosition> extends SlotBase {
  label: string;
  icon?: ComponentType<{ className?: string }>;
  /** 不显示时返回 false(缺省显示) */
  visible?: (props: SlotProps[P]) => boolean;
  /** 点了之后渲染的对话框;关闭时调 onClose */
  Dialog: ComponentType<SlotProps[P] & { onClose: () => void }>;
}

export interface PanelSlot<P extends PanelPosition = PanelPosition> extends SlotBase {
  Component: ComponentType<SlotProps[P]>;
}

export type SlotEntry<P extends SlotPosition> = P extends ActionPosition
  ? ActionSlot<P>
  : P extends PanelPosition
    ? PanelSlot<P>
    : never;

export interface SlotRegistry {
  register<P extends SlotPosition>(position: P, entry: SlotEntry<P>): void;
  entries<P extends SlotPosition>(position: P): SlotEntry<P>[];
}

export function createSlotRegistry(): SlotRegistry {
  const byPos = new Map<SlotPosition, SlotBase[]>();
  return {
    register(position, entry) {
      const list = byPos.get(position) ?? [];
      if (list.some((e) => e.id === entry.id)) throw new Error(`插槽 ${position} 已有 ${entry.id}`);
      byPos.set(position, [...list, entry]);
    },
    entries<P extends SlotPosition>(position: P) {
      const list = (byPos.get(position) ?? []) as SlotEntry<P>[];
      // 稳定排序:order 相同保持注册顺序
      return list
        .map((e, i) => ({ e, i }))
        .sort((a, b) => (a.e.order ?? 100) - (b.e.order ?? 100) || a.i - b.i)
        .map((x) => x.e);
    },
  };
}

/** 应用里唯一的插槽表(features/index.ts 往这里注册) */
export const slots: SlotRegistry = createSlotRegistry();

/** 动作类插槽里当前可见的项 */
export function visibleActions<P extends ActionPosition>(
  registry: SlotRegistry,
  position: P,
  props: SlotProps[P],
): ActionSlot<P>[] {
  return (registry.entries(position) as ActionSlot<P>[]).filter((a) => a.visible?.(props) ?? true);
}