import type { RouteLocationNormalized } from 'vue-router';
import { defineStore } from 'pinia';
import {
  DEFAULT_ROUTE,
  DEFAULT_ROUTE_NAME,
  REDIRECT_ROUTE_NAME,
} from '@/router/constants';
import { isString } from '@/utils/is';
import { useRbacUserStore } from '@/store/modules/rbac-user';
import { buildMenuTitleMaps, resolveMenuTitleByPath, resolveMenuTitleFromTree } from '@/utils/menu-display';
import type { MenuTreeDto } from '@/api/rbac';
import { TabBarState, TagProps } from './types';

/** keep-alive 同时缓存的页面上限（LRU），避免页签开太多越切越顿 */
export const MAX_KEEP_ALIVE_TABS = 10;

function resolveRouteTabTitle(route: RouteLocationNormalized): string {
  const rbacUserStore = useRbacUserStore();
  const { pathToTitle } = buildMenuTitleMaps(rbacUserStore.menus as MenuTreeDto[]);
  const menuTitle = resolveMenuTitleByPath(route.path, pathToTitle);
  if (menuTitle) {
    return menuTitle;
  }

  const metaTitle = route.meta?.title;
  if (typeof metaTitle === 'string' && metaTitle.trim()) {
    return metaTitle.trim();
  }

  return String(route.name || route.path || '');
}

const formatTag = (route: RouteLocationNormalized): TagProps => {
  const { name, meta, fullPath, query } = route;
  return {
    title: resolveRouteTabTitle(route),
    name: String(name),
    fullPath,
    query,
    ignoreCache: meta.ignoreCache,
  };
};

const BAN_LIST = [REDIRECT_ROUTE_NAME];

const useTabBarStore = defineStore('tabBar', {
  state: (): TabBarState => ({
    cacheTabList: new Set([DEFAULT_ROUTE_NAME]),
    tagList: [DEFAULT_ROUTE],
  }),

  getters: {
    getTabList(): TagProps[] {
      return this.tagList;
    },
    getCacheList(): string[] {
      return Array.from(this.cacheTabList);
    },
  },

  actions: {
    /** 超出上限时淘汰最久未访问的缓存（保留首页） */
    pruneCache(exceptName?: string) {
      while (this.cacheTabList.size > MAX_KEEP_ALIVE_TABS) {
        let removed = false;
        for (const name of this.cacheTabList) {
          if (name === DEFAULT_ROUTE_NAME || name === exceptName) {
            continue;
          }
          this.cacheTabList.delete(name);
          removed = true;
          break;
        }
        if (!removed) break;
      }
    },

    /** LRU：访问时挪到末尾，并裁剪超量缓存 */
    touchCache(name: string) {
      if (!isString(name) || name === '') return;
      if (this.cacheTabList.has(name)) {
        this.cacheTabList.delete(name);
      }
      this.cacheTabList.add(name);
      this.pruneCache(name);
    },

    updateTabList(route: RouteLocationNormalized) {
      if (BAN_LIST.includes(route.name as string)) return;
      this.tagList.push(formatTag(route));
      if (!route.meta.ignoreCache) {
        this.touchCache(String(route.name));
      }
    },
    deleteTag(idx: number, tag: TagProps) {
      this.tagList.splice(idx, 1);
      this.cacheTabList.delete(tag.name);
    },
    addCache(name: string) {
      if (isString(name) && name !== '') {
        this.touchCache(name);
      }
    },
    deleteCache(tag: TagProps) {
      this.cacheTabList.delete(tag.name);
    },
    freshTabList(tags: TagProps[]) {
      this.tagList = tags;
      this.cacheTabList.clear();
      this.cacheTabList.add(DEFAULT_ROUTE_NAME);
      this.tagList
        .filter((el) => !el.ignoreCache)
        .map((el) => el.name)
        .forEach((x) => {
          if (x && x !== DEFAULT_ROUTE_NAME) {
            this.cacheTabList.add(x);
          }
        });
      this.pruneCache();
    },
    resetTabList() {
      this.tagList = [DEFAULT_ROUTE];
      this.cacheTabList.clear();
      this.cacheTabList.add(DEFAULT_ROUTE_NAME);
    },
    delVisitedRoute(path: string) {
      const idx = this.tagList.findIndex(tag => tag.fullPath === path);
      if (idx !== -1) {
        const tag = this.tagList[idx];
        this.deleteTag(idx, tag);
      }
    },
    /** 拖动排序标签：将 fromIndex 位置的标签移动到 toIndex */
    reorderTabs(fromIndex: number, toIndex: number) {
      if (fromIndex === toIndex || fromIndex < 0 || toIndex < 0) return;
      const list = [...this.tagList];
      const [item] = list.splice(fromIndex, 1);
      list.splice(toIndex, 0, item);
      this.freshTabList(list);
    },
    /** 菜单加载后刷新标签标题（使用 RBAC 菜单名称） */
    refreshTagTitles() {
      const rbacUserStore = useRbacUserStore();
      const menus = rbacUserStore.menus as MenuTreeDto[];
      this.tagList = this.tagList.map((tag) => ({
        ...tag,
        title: resolveMenuTitleFromTree(menus, tag.fullPath, tag.title) || tag.title,
      }));
    },
  },
});

export default useTabBarStore;