'use client';

import { create } from 'zustand';

export type AppTab = {
  id: string;
  title: string;
  path: string;
  pinned?: boolean;
};

type TabStoreState = {
  tabs: AppTab[];
  activeId: string;
  open: (tab: Omit<AppTab, 'id'> & { id?: string }) => void;
  /** 同 path 则仅激活，否则新开 */
  openOrActivate: (tab: { path: string; title: string }) => void;
  /** 浏览器地址变化时同步当前页签 */
  syncFromPath: (path: string) => void;
  /** 切换租户：保留固定「概览」并重置页签 */
  resetForTenantSwitch: () => void;
  close: (id: string) => string | null;
  activate: (id: string) => void;
};

let seq = 0;

const overview: AppTab = {
  id: 'overview',
  title: '概览',
  path: '/dashboard',
  pinned: true,
};

function titleFromPath(path: string): string {
  const parts = path.split('/').filter(Boolean);
  const last = parts[parts.length - 1];
  return last ? decodeURIComponent(last) : path;
}

export const useTabStore = create<TabStoreState>((set, get) => ({
  tabs: [overview],
  activeId: 'overview',

  open: (tab) => {
    const id = tab.id ?? `t-${++seq}`;
    set((s) => ({
      tabs: [...s.tabs, { ...tab, id }],
      activeId: id,
    }));
  },

  openOrActivate: ({ path, title }) => {
    const normalized = path.startsWith('/') ? path : `/${path}`;
    set((s) => {
      const hit = s.tabs.find((t) => t.path === normalized);
      if (hit) {
        return { activeId: hit.id };
      }
      const id = `t-${++seq}`;
      return {
        tabs: [...s.tabs, { id, path: normalized, title: title || titleFromPath(normalized) }],
        activeId: id,
      };
    });
  },

  syncFromPath: (path) => {
    const normalized = path.startsWith('/') ? path : `/${path}`;
    if (!normalized.startsWith('/dashboard')) {
      return;
    }
    set((s) => {
      const hit = s.tabs.find((t) => t.path === normalized);
      if (hit) {
        return { activeId: hit.id };
      }
      const id = `t-${++seq}`;
      return {
        tabs: [
          ...s.tabs,
          {
            id,
            path: normalized,
            title: titleFromPath(normalized),
          },
        ],
        activeId: id,
      };
    });
  },

  resetForTenantSwitch: () => {
    set({
      tabs: [overview],
      activeId: 'overview',
    });
  },

  close: (id) => {
    const { tabs, activeId } = get();
    const t = tabs.find((x) => x.id === id);
    if (!t || t.pinned) {
      return null;
    }
    const nextTabs = tabs.filter((x) => x.id !== id);
    let nextActive = activeId;
    if (activeId === id) {
      const idx = tabs.findIndex((x) => x.id === id);
      const neighbor = tabs[idx - 1] ?? tabs[idx + 1];
      nextActive = neighbor?.id ?? 'overview';
    }
    set({ tabs: nextTabs, activeId: nextActive });
    const activeTab = get().tabs.find((x) => x.id === nextActive);
    return activeTab?.path ?? '/dashboard';
  },

  activate: (id) => set({ activeId: id }),
}));