import { useState, useEffect, useMemo } from 'react';
import { Outlet, useLocation, useNavigate } from 'react-router-dom';
import {
  LayoutDashboard, Database, Server, Zap, Leaf,
  Code2, FileEdit, Users, ShieldCheck, FolderLock, Shield, GitBranch, Bell,
  LogOut, Settings, Timer, ScrollText, Megaphone, Sun, Moon, BookOpen,
  ChevronRight, Monitor
} from 'lucide-react';
import { menuSections, menuItems } from '@/constants/menu';
import { useAuth } from '@/hooks/useAuth';
import { useTheme, THEME_OPTIONS } from '@/hooks/useTheme';
import request from '@/api/request';

const iconMap: Record<string, React.ElementType> = {
  LayoutDashboard, Database, Server, Zap, Leaf,
  Code2, FileEdit, Users, ShieldCheck, FolderLock, Shield, GitBranch, Bell,
  Settings, Timer, ScrollText, Megaphone, BookOpen,
};

export default function Layout() {
  const { user, logout, visibleMenuItems } = useAuth();
  const { theme, toggleTheme } = useTheme();
  const location = useLocation();
  const navigate = useNavigate();
  const currentPath = location.pathname.split('/')[1] || 'dashboard';
  const [pendingCount, setPendingCount] = useState(0);

  useEffect(() => {
    request.get('/dashboard/stats')
      .then((data: any) => setPendingCount(data?.ticket_pending ?? 0))
      .catch(() => {});
  }, [location.pathname]);

  // Build breadcrumb info from current path
  const breadcrumbInfo = useMemo(() => {
    const currentItem = menuItems.find(m => m.id === currentPath);
    if (!currentItem) {
      return { sectionLabel: '', pageLabel: '仪表盘' };
    }
    const section = menuSections.find(s => s.id === currentItem.section);
    return {
      sectionLabel: section?.label || '',
      pageLabel: currentItem.label,
    };
  }, [currentPath]);

  const themeOption = useMemo(() => THEME_OPTIONS.find(o => o.id === theme), [theme]);
  const themeIcon = useMemo(() => {
    if (!themeOption) return <Monitor className="w-4 h-4" />;
    if (themeOption.isDark === 'system') return <Monitor className="w-4 h-4" />;
    if (themeOption.isDark) return <Moon className="w-4 h-4" />;
    return <Sun className="w-4 h-4" />;
  }, [themeOption]);

  return (
    <div className="flex h-screen bg-[var(--dg-bg-primary)] text-[var(--dg-text-primary)] overflow-hidden">
      {/* 侧边栏 — z-[200] 永远在弹框之上 */}
      <aside className="relative z-[200] hidden md:flex flex-col bg-[var(--dg-bg-secondary)] border-r border-[var(--dg-border)] w-[220px] min-w-[220px]">
        {/* Logo */}
        <div className="h-14 flex items-center px-4">
          <div className="flex items-center gap-2.5">
            <div className="w-7 h-7 rounded-lg dg-gradient-br flex items-center justify-center flex-shrink-0">
              <Shield className="w-4 h-4 text-white" />
            </div>
            <span className="text-base font-bold dg-gradient-text whitespace-nowrap">
              OpsxSQL
            </span>
          </div>
        </div>

        {/* 菜单 */}
        <nav className="flex-1 overflow-y-auto scrollbar-thin py-1">
          {menuSections.map(section => {
            const items = visibleMenuItems.filter(item => item.section === section.id);
            if (items.length === 0) return null;
            return (
              <div key={section.id} className="mb-1">
                <div className="px-4 py-1.5 text-[10px] font-semibold uppercase tracking-wider text-[var(--dg-text-muted)]">
                  {section.label}
                </div>
                {items.map(item => {
                  const Icon = iconMap[item.icon] || Database;
                  const isActive = currentPath === item.id;
                  return (
                    <div
                      key={item.id}
                      onClick={() => navigate('/' + item.id)}
                      className={
                        'group flex items-center mx-2 px-3 py-2 rounded-lg cursor-pointer '
                        + 'transition-all duration-200 relative text-[13px] '
                        + (isActive
                          ? 'bg-[var(--dg-blue)]/10 text-[var(--dg-blue)] font-medium'
                          : 'text-[var(--dg-text-secondary)] '
                            + 'hover:bg-[var(--dg-bg-hover)] hover:text-[var(--dg-text-primary)] '
                            + 'hover:ml-0.5')
                      }
                    >
                      {/* Active indicator bar */}
                      {isActive && (
                        <div
                          className="absolute left-0 top-1/2 -translate-y-1/2 w-[3px] h-5 rounded-r animate-[slideInLeft_200ms_ease-out]"
                          style={{
                            background: 'var(--dg-blue)',
                            boxShadow: '0 0 0 1px color-mix(in srgb, var(--dg-blue) 30%, transparent)',
                          }}
                        />
                      )}
                      <Icon
                        className={
                          'w-4 h-4 flex-shrink-0 transition-colors duration-200 '
                          + (isActive
                            ? 'text-[var(--dg-blue)]'
                            : 'group-hover:text-[var(--dg-blue)]')
                        }
                      />
                      <span className="ml-2.5">{item.label}</span>
                    </div>
                  );
                })}
              </div>
            );
          })}
        </nav>
      </aside>

      {/* 主内容区 */}
      <main id="app-main" className="relative flex-1 flex flex-col min-w-0 overflow-hidden">
        {/* 顶部栏 — z-[200] 永远在弹框之上 */}
        <header className="relative z-[200] h-14 bg-[var(--dg-bg-secondary)] border-b border-[var(--dg-border)] flex items-center justify-between px-3 md:px-5 flex-shrink-0">
          {/* Breadcrumb area */}
          <div className="flex items-center gap-1.5 text-sm min-w-0">
            <span className="text-[var(--dg-text-muted)] font-medium">OpsxSQL</span>
            {breadcrumbInfo.sectionLabel && (
              <span className="hidden sm:contents">
                <ChevronRight className="w-3.5 h-3.5 text-[var(--dg-text-muted)] opacity-50" />
                <span className="text-[var(--dg-text-muted)] opacity-70">{breadcrumbInfo.sectionLabel}</span>
              </span>
            )}
            <ChevronRight className="w-3.5 h-3.5 text-[var(--dg-text-muted)] opacity-50" />
            <span className="text-[var(--dg-text-primary)] font-medium truncate">{breadcrumbInfo.pageLabel}</span>
          </div>

          {/* Right actions */}
          <div className="flex items-center gap-2">
            {/* Theme toggle with tooltip */}
            <button
              onClick={toggleTheme}
              className="w-8 h-8 rounded-lg flex items-center justify-center text-[var(--dg-text-muted)] hover:bg-[var(--dg-bg-hover)] hover:text-[var(--dg-text-primary)] transition-all duration-200"
              title={`当前主题: ${themeOption?.name || theme}\n点击切换下一个主题`}
            >
              {themeIcon}
            </button>

            {/* Notification bell */}
            <button onClick={() => navigate('/tickets')}
              className="w-8 h-8 rounded-lg flex items-center justify-center text-[var(--dg-text-muted)] hover:bg-[var(--dg-bg-hover)] hover:text-[var(--dg-text-primary)] transition-all duration-200 relative">
              <Bell className="w-4 h-4" />
              {pendingCount > 0 && (
                <span className="absolute -top-0.5 -right-0.5 min-w-[16px] h-4 px-1 bg-red-500 rounded-full text-[10px] text-white font-bold flex items-center justify-center animate-pulse">
                  {pendingCount > 99 ? '99+' : pendingCount}
                </span>
              )}
            </button>

            <div className="w-px h-5 bg-[var(--dg-border)] mx-1" />

            {/* User area */}
            <div className="flex items-center gap-2 pl-1">
              <div className="w-7 h-7 rounded-full dg-gradient-br flex items-center justify-center text-white text-xs font-semibold flex-shrink-0">
                {user.avatar}
              </div>
              <span className="hidden sm:inline text-sm text-[var(--dg-text-secondary)] max-w-[80px] truncate">{user.username}</span>
              <button
                onClick={() => { logout(); navigate('/login'); }}
                className="w-8 h-8 rounded-lg flex items-center justify-center text-[var(--dg-text-muted)] hover:bg-red-500/10 hover:text-red-400 transition-colors duration-200"
                title="退出登录"
              >
                <LogOut className="w-4 h-4" />
              </button>
            </div>
          </div>
        </header>

        {/* 页面内容 */}
        <div className="flex-1 overflow-y-auto scrollbar-thin p-3 md:p-5 pb-20 md:pb-5">
          <Outlet />
        </div>
      </main>

      <nav className="fixed bottom-0 left-0 right-0 z-[210] md:hidden border-t border-[var(--dg-border)] bg-[var(--dg-bg-secondary)]/95 backdrop-blur">
        <div className="flex overflow-x-auto px-2 py-1.5 gap-1 scrollbar-thin">
          {visibleMenuItems.map(item => {
            const Icon = iconMap[item.icon] || Database;
            const isActive = currentPath === item.id;
            return (
              <button
                key={item.id}
                onClick={() => navigate('/' + item.id)}
                className={`min-w-[70px] flex flex-col items-center justify-center gap-1 rounded-lg px-2 py-1.5 text-[11px] transition-colors ${
                  isActive
                    ? 'bg-[var(--dg-blue)]/12 text-[var(--dg-blue)]'
                    : 'text-[var(--dg-text-muted)] hover:bg-[var(--dg-bg-hover)] hover:text-[var(--dg-text-primary)]'
                }`}
              >
                <Icon className="w-4 h-4" />
                <span className="max-w-[64px] truncate">{item.label}</span>
              </button>
            );
          })}
        </div>
      </nav>

      {/* Keyframe animation for active indicator */}
      <style>{`
        @keyframes slideInLeft {
          from {
            opacity: 0;
            transform: translateY(-50%) scaleX(0);
            transform-origin: left;
          }
          to {
            opacity: 1;
            transform: translateY(-50%) scaleX(1);
            transform-origin: left;
          }
        }
      `}</style>
    </div>
  );
}