"use client";

import { Menu } from "@base-ui/react/menu";
import {
  ChevronDown,
  ChevronRight,
  Clock3,
  FileText,
  LogOut,
  Settings,
  WalletCards,
  MessageSquareText,
  SquarePen,
  Star,
  UserPlus,
  UserRound,
  Users,
} from "lucide-react";
import { useEffect, useRef } from "react";
import type { Ref } from "react";
import {
  Sidebar,
  SidebarContent,
  SidebarFooter,
  SidebarGroup,
  SidebarGroupContent,
  SidebarGroupLabel,
  SidebarHeader,
  SidebarMenu,
  SidebarMenuButton,
  SidebarMenuItem,
  SidebarRail,
  useSidebar,
} from "@/components/ui/sidebar";
import {
  SidebarSessionRow,
  type SidebarSession,
  type SidebarSessionControls,
} from "@/components/sidebar-session-row";
import { ThemePreferenceMenu } from "@/components/theme-preference-menu";
import { UserAvatar } from "@/components/user-avatar";
import type { BeamAvatar } from "@/lib/beam-avatar";
import { groupSessionsByRecency } from "@/lib/session-groups";

export type SidebarAccount = {
  name: string;
  email: string;
  credits: number;
  initial: string;
  avatar: BeamAvatar | null;
};

export type SidebarChart = {
  readonly id: string;
  readonly name: string;
  readonly role: "self" | "other";
};

export type AppSidebarProps = {
  sessions: readonly SidebarSession[];
  charts: readonly SidebarChart[];
  activeSessionId: string | null;
  /** A rectification session whose Case is being opened and hydrated; its row says so, statically. */
  openingSessionId?: string | null;
  /** Open failed for this history session; shown under that row only. */
  openErrorSessionId?: string | null;
  openErrorMessage?: string;
  account: SidebarAccount;
  accountMenuOpen: boolean;
  accountTriggerRef: Ref<HTMLButtonElement>;
  newChatDisabled: boolean;
  creatingSession: boolean;
  sessionControls: SidebarSessionControls;
  onAccountMenuOpenChange: (open: boolean) => void;
  onNewChat: () => void;
  onOpenReports: () => void;
  onSelectSession: (sessionId: string) => void;
  onSelectChart: (chartId: string) => void;
  onAddChart: () => void;
  onOpenProfile: () => void;
  onOpenChartLibrary: () => void;
  onOpenGeneral: () => void;
  onOpenBilling: () => void;
  onOpenLogout: () => void;
};

export function AppSidebar({
  sessions,
  charts,
  activeSessionId,
  openingSessionId = null,
  openErrorSessionId = null,
  openErrorMessage = "",
  account,
  accountMenuOpen,
  accountTriggerRef,
  newChatDisabled,
  creatingSession,
  sessionControls,
  onAccountMenuOpenChange,
  onNewChat,
  onOpenReports,
  onSelectSession,
  onSelectChart,
  onAddChart,
  onOpenProfile,
  onOpenChartLibrary,
  onOpenGeneral,
  onOpenBilling,
  onOpenLogout,
}: AppSidebarProps) {
  const { isMobile, setOpen, setOpenMobile, state, viewport } = useSidebar();
  const firstSessionRef = useRef<HTMLButtonElement>(null);
  const historyHeadingRef = useRef<HTMLElement>(null);
  const loadMoreRef = useRef<HTMLDivElement>(null);
  const isCollapsedDesktop = state === "collapsed" && !isMobile;
  const showExpandedContent = !isCollapsedDesktop;
  const menuPlacement = `${viewport}:${state}`;
  const previousMenuPlacement = useRef(menuPlacement);
  const favoriteSessions = sessions.filter((session) => session.pinned);
  const historySessions = sessions.filter((session) => !session.pinned);
  const historyGroups = groupSessionsByRecency(historySessions);

  useEffect(() => {
    if (!sessionControls.hasMore || !sessionControls.onLoadMore) return;
    const node = loadMoreRef.current;
    if (!node) return;
    const observer = new IntersectionObserver((entries) => {
      if (entries.some((entry) => entry.isIntersecting)) sessionControls.onLoadMore?.();
    });
    observer.observe(node);
    return () => observer.disconnect();
  }, [historySessions.length, sessionControls.hasMore, sessionControls.onLoadMore]);

  useEffect(() => {
    if (previousMenuPlacement.current !== menuPlacement && accountMenuOpen) {
      onAccountMenuOpenChange(false);
    }
    previousMenuPlacement.current = menuPlacement;
  }, [accountMenuOpen, menuPlacement, onAccountMenuOpenChange]);

  function handleNewChat() {
    onNewChat();
    if (isMobile) setOpenMobile(false);
  }

  function handleOpenReports() {
    onOpenReports();
    if (isMobile) setOpenMobile(false);
  }

  function handleExpandHistory() {
    setOpen(true);
    window.requestAnimationFrame(() => {
      (firstSessionRef.current ?? historyHeadingRef.current)?.focus();
    });
  }

  function renderSession(session: SidebarSession, index: number) {
    return (
      <SidebarMenuItem key={session.id}>
        <SidebarSessionRow
          ref={index === 0 ? firstSessionRef : undefined}
          session={session}
          active={session.id === activeSessionId}
          opening={session.id === openingSessionId}
          error={session.id === openErrorSessionId && openErrorMessage ? openErrorMessage : undefined}
          disabled={sessionControls.disabled}
          menuOpen={sessionControls.menuSessionId === session.id}
          onMenuOpenChange={(open) => sessionControls.onMenuSessionChange(open ? session.id : null)}
          onSelect={() => {
            onSelectSession(session.id);
            if (isMobile) setOpenMobile(false);
          }}
          onTogglePinned={() => sessionControls.onTogglePinned(session.id)}
          onRename={() => sessionControls.onRename(session.id)}
          onShare={() => sessionControls.onShare(session.id)}
          onToggleArchived={() => sessionControls.onToggleArchived(session.id)}
          onDelete={() => sessionControls.onDelete(session.id)}
        />
      </SidebarMenuItem>
    );
  }

  return (
    <Sidebar className="sidebar" aria-label="对话导航">
      <SidebarHeader className="sidebar-header">
        <div className="brand-row">
          <span className="brand-mark" aria-hidden="true" />
          {showExpandedContent ? <strong>Jyotisha</strong> : null}
        </div>
        <SidebarMenu>
          <SidebarMenuItem>
            <SidebarMenuButton
              className="new-chat"
              type="button"
              tooltip="新对话"
              disabled={newChatDisabled}
              onClick={handleNewChat}
            >
              <SquarePen size={18} strokeWidth={1.75} aria-hidden="true" />
              {showExpandedContent ? <span>{creatingSession ? "正在创建" : "新建对话"}</span> : null}
            </SidebarMenuButton>
          </SidebarMenuItem>
          <SidebarMenuItem>
            <SidebarMenuButton
              className="report-nav-button"
              type="button"
              tooltip="我的报告"
              onClick={handleOpenReports}
            >
              <FileText size={18} strokeWidth={1.75} aria-hidden="true" />
              {showExpandedContent ? <span>我的报告</span> : null}
            </SidebarMenuButton>
          </SidebarMenuItem>
        </SidebarMenu>
      </SidebarHeader>

      <SidebarContent>
        {showExpandedContent ? (
          <>
            <SidebarGroup className="chart-nav" aria-label="星盘列表">
              <div className="session-nav-header">
                <SidebarGroupLabel className="sidebar-label">
                  <Users size={18} strokeWidth={1.75} aria-hidden="true" />
                  星盘列表
                </SidebarGroupLabel>
                <button
                  className="session-nav-toggle"
                  type="button"
                  aria-label="添加星盘"
                  onClick={onAddChart}
                >
                  <UserPlus size={18} strokeWidth={1.75} aria-hidden="true" />
                </button>
              </div>
              <SidebarGroupContent className="sidebar-nested">
                {charts.length === 0 ? <p className="sidebar-empty">还没有星盘</p> : (
                  <div className="chart-nav-list">
                    {charts.map((chart) => (
                      <button
                        className="chart-nav-chip"
                        key={chart.id}
                        type="button"
                        onClick={() => onSelectChart(chart.id)}
                      >
                        {chart.name}
                      </button>
                    ))}
                  </div>
                )}
              </SidebarGroupContent>
            </SidebarGroup>

            <SidebarGroup className="session-nav" aria-label="收藏对话">
              <details className="sidebar-section" open>
                <summary className="sidebar-section-summary">
                  <Star size={18} strokeWidth={1.75} aria-hidden="true" />
                  <span>收藏对话</span>
                  <ChevronDown className="sidebar-section-chevron" size={16} strokeWidth={1.75} aria-hidden="true" />
                </summary>
                <SidebarGroupContent className="sidebar-nested">
                  {favoriteSessions.length === 0 ? <p className="sidebar-empty">还没有收藏，可在对话的「更多操作」里收藏</p> : (
                    <SidebarMenu className="session-list">
                      {favoriteSessions.map((session, index) => renderSession(session, index))}
                    </SidebarMenu>
                  )}
                </SidebarGroupContent>
              </details>
            </SidebarGroup>

            <SidebarGroup className="session-nav" aria-label={sessionControls.showingArchived ? "归档记录" : "历史对话"}>
              <details className="sidebar-section" open>
                <summary className="sidebar-section-summary" ref={historyHeadingRef} tabIndex={-1}>
                  <Clock3 size={18} strokeWidth={1.75} aria-hidden="true" />
                  <span>{sessionControls.showingArchived ? "归档记录" : "历史对话"}</span>
                  <ChevronDown className="sidebar-section-chevron" size={16} strokeWidth={1.75} aria-hidden="true" />
                </summary>
                <SidebarGroupContent className="sidebar-nested">
                  {historySessions.length === 0 ? <p className="sidebar-empty">暂无对话，点上方「新建对话」开始</p> : (
                    <SidebarMenu className="session-list">
                      {historyGroups.map((group) => (
                        <div key={group.key}>
                          <p className="sidebar-group-label">{group.label}</p>
                          {group.sessions.map((session) => renderSession(
                            session,
                            favoriteSessions.length + historySessions.findIndex((item) => item.id === session.id),
                          ))}
                        </div>
                      ))}
                      {sessionControls.hasMore ? <div ref={loadMoreRef} aria-hidden className="session-list-sentinel" /> : null}
                    </SidebarMenu>
                  )}
                </SidebarGroupContent>
              </details>
            </SidebarGroup>
          </>
        ) : (
          <SidebarMenu>
            <SidebarMenuItem>
              <SidebarMenuButton
                type="button"
                tooltip="聊天记录"
                aria-label="聊天记录"
                onClick={handleExpandHistory}
              >
                <MessageSquareText size={18} strokeWidth={1.75} aria-hidden="true" />
              </SidebarMenuButton>
            </SidebarMenuItem>
          </SidebarMenu>
        )}
      </SidebarContent>

      <SidebarFooter className="sidebar-footer">
        <Menu.Root open={accountMenuOpen} onOpenChange={onAccountMenuOpenChange} modal={false}>
          <Menu.Trigger
            className="profile-trigger"
            ref={accountTriggerRef}
            type="button"
          >
            {account.avatar
              ? <UserAvatar avatar={account.avatar} size={32} className="profile-avatar" />
              : <span className="profile-initial" aria-hidden="true">{account.initial}</span>}
            {showExpandedContent ? <span><b>{account.name}</b></span> : null}
            {showExpandedContent ? <ChevronRight className={accountMenuOpen ? "chevron is-open" : "chevron"} aria-hidden="true" /> : null}
          </Menu.Trigger>
          <Menu.Portal>
            <Menu.Positioner
              side={isMobile || state === "expanded" ? "top" : "right"}
              align={isMobile || state === "expanded" ? "end" : "center"}
              sideOffset={8}
              collisionPadding={12}
            >
              <Menu.Popup className="account-menu-popup" aria-label="账户菜单">
                <div className="account-menu-identity">
                  {account.avatar
                    ? <UserAvatar avatar={account.avatar} size={40} className="account-menu-avatar" />
                    : <span className="account-menu-avatar" aria-hidden="true">{account.initial}</span>}
                  <span><b>{account.name}</b><small>{account.email}</small></span>
                </div>
                <Menu.Item className="account-menu-item" onClick={onOpenProfile}>
                  <UserRound aria-hidden="true" /><span>个人资料</span><ChevronRight aria-hidden="true" />
                </Menu.Item>
                <Menu.Item className="account-menu-item" onClick={onOpenChartLibrary}>
                  <Users aria-hidden="true" /><span>星盘资料</span><ChevronRight aria-hidden="true" />
                </Menu.Item>
                <Menu.Item className="account-menu-item" onClick={onOpenGeneral}>
                  <Settings aria-hidden="true" /><span>通用设置</span><ChevronRight aria-hidden="true" />
                </Menu.Item>
                <Menu.Item className="account-menu-item" onClick={onOpenBilling}>
                  <WalletCards aria-hidden="true" /><span>账户与点数</span><small>{account.credits} 点</small>
                </Menu.Item>
                <Menu.Separator className="account-menu-separator" />
                <ThemePreferenceMenu />
                <Menu.Separator className="account-menu-separator" />
                <Menu.Item className="account-menu-item account-menu-danger" onClick={onOpenLogout}>
                  <LogOut aria-hidden="true" /><span>退出登录</span>
                </Menu.Item>
              </Menu.Popup>
            </Menu.Positioner>
          </Menu.Portal>
        </Menu.Root>
      </SidebarFooter>
      <SidebarRail />
    </Sidebar>
  );
}