import React, { useEffect, useRef, useState } from "react";
import { Command as CommandPrimitive } from "cmdk";
import { useTranslation } from "react-i18next";
import { cn } from "@/lib/utils";
import { Kbd } from "@/components/kbd";
import {
  Command,
  CommandItem,
  CommandList,
  CommandGroup,
  CommandSeparator,
} from "@/components/command";
import {
  Server,
  Settings,
  Globe,
  Plus,
  MessagesSquare,
  LifeBuoy,
  Search,
  User,
  KeyRound,
  Clock,
  Folder,
  Pencil,
} from "lucide-react";
import { getRecentActivity, type RecentActivityItem } from "@/main-axios";
import type { Host, TabType, Tab } from "@/types/ui-types";
import { canEditHost } from "@/sidebar/host-permissions";
import { RAIL_UTILITY_ITEMS, useRailItems } from "@/sidebar/rail-items";
import {
  defaultConnectAction,
  hostActionsFor,
  runHostAction,
  useHostActions,
} from "@/sidebar/host-contributions";
import {
  filterPaletteItems,
  loadPaletteGroup,
  paletteEntriesFor,
  usePaletteEntries,
  usePaletteGroups,
  type PaletteItemDef,
} from "./palette-registry";
import { activityTarget } from "@/lib/activity-types";
import { shell } from "@/plugin-host/shell-bridge";

interface CommandPaletteProps {
  isOpen: boolean;
  setIsOpen: (isOpen: boolean) => void;
  hosts: Host[];
  terminalTabs?: Tab[];
  activeTabId?: string;
  onOpenTab: (type: TabType, label?: string, pendingEvent?: string) => void;
  /** Opens a sidebar panel. Kept separate from onOpenTab, which is TabType-shaped. */
  onOpenPanel?: (view: string) => void;
}

export function CommandPalette({
  isOpen,
  setIsOpen,
  hosts,
  terminalTabs = [],
  activeTabId = "",
  onOpenTab,
  onOpenPanel,
}: CommandPaletteProps) {
  const { t } = useTranslation();
  const railItems = useRailItems();
  const hostActions = useHostActions();
  const paletteEntries = usePaletteEntries();
  const inputRef = useRef<HTMLInputElement>(null);
  const [search, setSearch] = useState("");
  const [recentActivity, setRecentActivity] = useState<RecentActivityItem[]>(
    [],
  );
  const paletteGroups = usePaletteGroups();
  const [groupItems, setGroupItems] = useState<
    Record<string, PaletteItemDef[]>
  >({});
  const [selectedValue, setSelectedValue] = useState("");

  useEffect(() => {
    if (isOpen) {
      setTimeout(() => inputRef.current?.focus(), 50);
      setSearch("");
      getRecentActivity(5)
        .then(setRecentActivity)
        .catch(() => {});
    }
  }, [isOpen]);

  useEffect(() => {
    if (!isOpen) return;
    let cancelled = false;
    for (const group of paletteGroups) {
      void loadPaletteGroup(group).then((items) => {
        if (!cancelled) {
          setGroupItems((prev) => ({ ...prev, [group.id]: items }));
        }
      });
    }
    return () => {
      cancelled = true;
    };
  }, [isOpen, paletteGroups]);

  useEffect(() => {
    if (!isOpen) return;

    const handleKeyDown = (e: KeyboardEvent) => {
      if (e.key === "Escape") {
        e.preventDefault();
        e.stopPropagation();
        setIsOpen(false);
      }
    };
    window.addEventListener("keydown", handleKeyDown, true);
    return () => window.removeEventListener("keydown", handleKeyDown, true);
  }, [isOpen, setIsOpen]);

  const filteredHosts = hosts.filter((h) => {
    const query = search.toLowerCase();
    return (
      h.name.toLowerCase().includes(query) ||
      h.ip.toLowerCase().includes(query) ||
      h.username.toLowerCase().includes(query) ||
      h.tags?.some((tag) => tag.toLowerCase().includes(query))
    );
  });

  // Group hosts by folder; ungrouped hosts appear first under an implicit root group
  const groupedHosts: { folder: string | null; hosts: Host[] }[] = [];
  const folderMap = new Map<string, Host[]>();
  const ungrouped: Host[] = [];
  for (const h of filteredHosts) {
    if (h.folder) {
      if (!folderMap.has(h.folder)) folderMap.set(h.folder, []);
      folderMap.get(h.folder)!.push(h);
    } else {
      ungrouped.push(h);
    }
  }
  if (ungrouped.length > 0)
    groupedHosts.push({ folder: null, hosts: ungrouped });
  for (const [folder, fhosts] of folderMap) {
    groupedHosts.push({ folder, hosts: fhosts });
  }

  useEffect(() => {
    if (!isOpen) return;
    const firstHost = filteredHosts[0];
    if (search.trim() && firstHost) {
      setSelectedValue(`host-${firstHost.id}`);
      return;
    }
    setSelectedValue("quick-action-add-host");
  }, [filteredHosts, isOpen, search]);

  const activeTargetTab =
    terminalTabs.find((tab) => tab.id === activeTabId) ?? terminalTabs[0];

  const handleAction = (action: () => void) => {
    action();
    setIsOpen(false);
  };
  const showHostResultsFirst = search.trim().length > 0;

  if (!isOpen) return null;

  return (
    <div
      className={cn(
        "fixed inset-0 z-[100] flex items-start justify-center pt-[15vh] bg-background/40 backdrop-blur-sm transition-all duration-200 animate-in fade-in",
      )}
      onClick={() => setIsOpen(false)}
    >
      <div
        className={cn(
          "w-full max-w-2xl mx-4 overflow-hidden rounded-none border border-border bg-card shadow-2xl animate-in zoom-in-95 duration-200",
        )}
        onClick={(e) => e.stopPropagation()}
      >
        <Command
          className="rounded-none"
          shouldFilter={false}
          loop
          value={selectedValue}
          onValueChange={setSelectedValue}
        >
          <div className="flex items-center border-b border-border px-4 py-1">
            <Search className="size-4 text-muted-foreground mr-3" />
            <CommandPrimitive.Input
              ref={inputRef}
              value={search}
              onValueChange={setSearch}
              placeholder={t("commandPalette.searchPlaceholder")}
              className="flex-1 h-12 bg-transparent text-sm outline-none placeholder:text-muted-foreground"
            />
            <div className="flex items-center gap-1.5 ml-2">
              <Kbd className="bg-muted/50 border-none h-6 px-2 text-[11px] rounded-none">
                ESC
              </Kbd>
            </div>
          </div>

          <CommandList className="max-h-[60vh] thin-scrollbar flex flex-col">
            <CommandGroup
              heading={t("commandPalette.quickActions")}
              className="px-2"
            >
              <CommandItem
                value="quick-action-add-host"
                onSelect={() =>
                  handleAction(() =>
                    onOpenTab(
                      "host-manager",
                      undefined,
                      "host-manager:add-host",
                    ),
                  )
                }
                className="group flex items-center gap-3 px-3 py-2.5 rounded-none hover:bg-accent-brand/10 cursor-pointer"
              >
                <div className="size-8 rounded-none bg-muted flex items-center justify-center group-hover:bg-accent-brand/20 transition-colors">
                  <Plus className="size-4 text-accent-brand" />
                </div>
                <div className="flex flex-col flex-1">
                  <span className="text-sm font-semibold">
                    {t("commandPalette.addNewHost")}
                  </span>
                  <span className="text-xs text-muted-foreground">
                    {t("commandPalette.addNewHostDesc")}
                  </span>
                </div>
              </CommandItem>

              <CommandItem
                value="quick-action-admin-settings"
                onSelect={() => handleAction(() => onOpenTab("admin-settings"))}
                className="group flex items-center gap-3 px-3 py-2.5 rounded-none hover:bg-accent-brand/10 cursor-pointer"
              >
                <div className="size-8 rounded-none bg-muted flex items-center justify-center group-hover:bg-accent-brand/20 transition-colors">
                  <Settings className="size-4 text-accent-brand" />
                </div>
                <div className="flex flex-col flex-1">
                  <span className="text-sm font-semibold">
                    {t("commandPalette.adminSettings")}
                  </span>
                  <span className="text-xs text-muted-foreground">
                    {t("commandPalette.adminSettingsDesc")}
                  </span>
                </div>
              </CommandItem>

              <CommandItem
                value="quick-action-user-profile"
                onSelect={() => handleAction(() => onOpenTab("user-profile"))}
                className="group flex items-center gap-3 px-3 py-2.5 rounded-none hover:bg-accent-brand/10 cursor-pointer"
              >
                <div className="size-8 rounded-none bg-muted flex items-center justify-center group-hover:bg-accent-brand/20 transition-colors">
                  <User className="size-4 text-accent-brand" />
                </div>
                <div className="flex flex-col flex-1">
                  <span className="text-sm font-semibold">
                    {t("commandPalette.userProfile")}
                  </span>
                  <span className="text-xs text-muted-foreground">
                    {t("commandPalette.userProfileDesc")}
                  </span>
                </div>
              </CommandItem>

              <CommandItem
                value="quick-action-add-credential"
                onSelect={() =>
                  handleAction(() =>
                    onOpenTab(
                      "host-manager",
                      undefined,
                      "host-manager:add-credential",
                    ),
                  )
                }
                className="group flex items-center gap-3 px-3 py-2.5 rounded-none hover:bg-accent-brand/10 cursor-pointer"
              >
                <div className="size-8 rounded-none bg-muted flex items-center justify-center group-hover:bg-accent-brand/20 transition-colors">
                  <KeyRound className="size-4 text-accent-brand" />
                </div>
                <div className="flex flex-col flex-1">
                  <span className="text-sm font-semibold">
                    {t("commandPalette.addCredential")}
                  </span>
                  <span className="text-xs text-muted-foreground">
                    {t("commandPalette.addCredentialDesc")}
                  </span>
                </div>
              </CommandItem>
            </CommandGroup>

            {onOpenPanel && (
              <>
                <CommandSeparator className="my-2" />
                <CommandGroup
                  heading={t("commandPalette.navigation")}
                  className="px-2"
                >
                  {[...railItems, ...RAIL_UTILITY_ITEMS]
                    .filter((item) => item.kind !== "tab")
                    .map((item) => {
                      const Icon = item.icon;
                      return (
                        <CommandItem
                          key={`nav-${item.id}`}
                          value={`nav-${item.id} ${t(item.labelKey)}`}
                          onSelect={() =>
                            handleAction(() => onOpenPanel(item.id))
                          }
                          className="group flex items-center gap-3 px-3 py-2.5 rounded-none hover:bg-accent-brand/10 cursor-pointer"
                        >
                          <div className="size-8 rounded-none bg-muted flex items-center justify-center group-hover:bg-accent-brand/20 transition-colors">
                            <Icon className="size-4 text-accent-brand" />
                          </div>
                          <span className="text-sm font-semibold flex-1">
                            {t(item.labelKey)}
                          </span>
                        </CommandItem>
                      );
                    })}
                </CommandGroup>
              </>
            )}

            {paletteGroups.map((group) => {
              const items = filterPaletteItems(
                groupItems[group.id] ?? [],
                search,
                group.showWhenEmpty,
              );
              if (items.length === 0) return null;
              return (
                <React.Fragment key={`group-${group.id}`}>
                  <CommandSeparator className="my-2" />
                  <CommandGroup heading={t(group.titleKey)} className="px-2">
                    {items.map((item) => {
                      const Icon = item.icon;
                      const blocked = !!item.needsTarget && !activeTargetTab;
                      return (
                        <CommandItem
                          key={`${group.id}-${item.id}`}
                          value={`group-${group.id}-${item.id}`}
                          onSelect={() => {
                            if (blocked) return;
                            handleAction(() =>
                              item.run({ targetTab: activeTargetTab, shell }),
                            );
                          }}
                          className={cn(
                            "group flex items-center gap-3 px-3 py-2.5 rounded-none hover:bg-accent-brand/10 cursor-pointer",
                            blocked && "pointer-events-none opacity-50",
                          )}
                        >
                          <div className="size-8 rounded-none bg-muted flex items-center justify-center group-hover:bg-accent-brand/20 transition-colors shrink-0">
                            {Icon && (
                              <Icon className="size-4 text-accent-brand" />
                            )}
                          </div>
                          <div className="flex flex-col flex-1 min-w-0">
                            <span className="text-sm font-semibold truncate">
                              {item.title}
                            </span>
                            {item.description && (
                              <span className="text-xs text-muted-foreground truncate font-mono">
                                {item.description}
                              </span>
                            )}
                          </div>
                          {(blocked || item.hint) && (
                            <span className="text-[10px] text-muted-foreground/60 shrink-0">
                              {blocked
                                ? t("commandPalette.noTargetTab")
                                : item.hint}
                            </span>
                          )}
                        </CommandItem>
                      );
                    })}
                  </CommandGroup>
                </React.Fragment>
              );
            })}

            {paletteEntriesFor(paletteEntries, "global").length > 0 && (
              <>
                <CommandSeparator className="my-2" />
                <CommandGroup
                  heading={t("commandPalette.pluginActions")}
                  className="px-2"
                >
                  {paletteEntriesFor(paletteEntries, "global").map((entry) => {
                    const Icon = entry.icon;
                    return (
                      <CommandItem
                        key={`plugin-${entry.id}`}
                        value={`plugin-${entry.id} ${t(entry.titleKey)} ${(entry.keywords ?? []).join(" ")}`}
                        onSelect={() => handleAction(() => entry.run(shell))}
                        className="group flex items-center gap-3 px-3 py-2.5 rounded-none hover:bg-accent-brand/10 cursor-pointer"
                      >
                        <div className="size-8 rounded-none bg-muted flex items-center justify-center group-hover:bg-accent-brand/20 transition-colors">
                          {Icon && (
                            <Icon className="size-4 text-accent-brand" />
                          )}
                        </div>
                        <span className="text-sm font-semibold flex-1">
                          {t(entry.titleKey)}
                        </span>
                      </CommandItem>
                    );
                  })}
                </CommandGroup>
              </>
            )}

            {recentActivity.length > 0 && (
              <>
                <CommandSeparator className="my-2" />
                <CommandGroup
                  heading={t("commandPalette.recentActivity")}
                  className="px-2"
                >
                  {recentActivity.map((item) => (
                    <CommandItem
                      key={item.id}
                      value={`recent-activity-${item.id}`}
                      onSelect={() =>
                        handleAction(() => {
                          const target = activityTarget(item.type);
                          if (target) onOpenTab(target.tab, item.hostName);
                        })
                      }
                      className="group flex items-center gap-3 px-3 py-2 rounded-none hover:bg-accent-brand/10 cursor-pointer"
                    >
                      <div className="size-7 rounded-none bg-muted flex items-center justify-center group-hover:bg-accent-brand/20 transition-colors text-muted-foreground group-hover:text-accent-brand">
                        {(() => {
                          const Icon = activityTarget(item.type)?.icon;
                          return Icon ? <Icon className="size-3.5" /> : null;
                        })()}
                      </div>
                      <div className="flex flex-col flex-1 min-w-0">
                        <span className="text-sm font-semibold truncate">
                          {item.hostName}
                        </span>
                        <span className="text-xs text-muted-foreground capitalize">
                          {item.type.replace("_", " ")}
                        </span>
                      </div>
                      <div className="flex items-center gap-1 text-muted-foreground/50">
                        <Clock className="size-3" />
                        <span className="text-[10px]">
                          {new Date(item.timestamp).toLocaleDateString()}
                        </span>
                      </div>
                    </CommandItem>
                  ))}
                </CommandGroup>
              </>
            )}

            <div className={cn(showHostResultsFirst && "order-first")}>
              {!showHostResultsFirst && <CommandSeparator className="my-2" />}

              <CommandGroup
                heading={t("commandPalette.serversAndHosts")}
                className="px-2"
              >
                {filteredHosts.length > 0 ? (
                  groupedHosts.map(({ folder, hosts: groupHosts }) => (
                    <div key={folder ?? "__root__"}>
                      {folder && (
                        <div className="flex items-center gap-1.5 px-3 py-1.5 text-[11px] font-semibold text-muted-foreground/60 uppercase tracking-wide">
                          <Folder className="size-3" />
                          {folder}
                        </div>
                      )}
                      {groupHosts.map((host, i) => (
                        <CommandItem
                          key={i}
                          value={`host-${host.id}`}
                          onSelect={() =>
                            handleAction(() => {
                              const action = defaultConnectAction(
                                hostActions,
                                host,
                              );
                              if (action) runHostAction(action, host, shell);
                            })
                          }
                          className="group flex items-center gap-3 px-3 py-2.5 rounded-none hover:bg-accent-brand/10 cursor-pointer"
                        >
                          <div className="size-8 rounded-none bg-muted flex items-center justify-center group-hover:bg-accent-brand/20 transition-colors shrink-0">
                            <Server
                              className={cn(
                                "size-4",
                                host.online
                                  ? "text-accent-brand"
                                  : "text-muted-foreground",
                              )}
                            />
                          </div>
                          <div className="flex flex-col flex-1 min-w-0">
                            <div className="flex items-center gap-2">
                              <span className="text-sm font-semibold truncate">
                                {host.name}
                              </span>
                              {host.isShared && (
                                <span className="text-[9px] px-1 py-px border border-accent-brand/30 bg-accent-brand/10 text-accent-brand shrink-0 leading-none uppercase tracking-wider">
                                  {t("hosts.sharing.sharedBadge")}
                                </span>
                              )}
                              {host.online && (
                                <span className="size-1.5 rounded-full bg-accent-brand animate-pulse shrink-0" />
                              )}
                            </div>
                            <span className="text-xs text-muted-foreground font-mono">
                              {host.username}@{host.ip}
                            </span>
                          </div>
                          <div className="flex items-center gap-0.5 opacity-0 group-hover:opacity-100 transition-opacity">
                            {hostActionsFor(hostActions, host).map((action) => {
                              const Icon = action.icon;
                              const label =
                                action.label?.(host) ?? t(action.titleKey);
                              return (
                                <button
                                  key={action.id}
                                  title={label}
                                  onClick={(e) => {
                                    e.stopPropagation();
                                    handleAction(() =>
                                      runHostAction(action, host, shell),
                                    );
                                  }}
                                  className="flex items-center justify-center size-7 rounded text-muted-foreground/50 hover:text-foreground hover:bg-muted-foreground/10 transition-colors"
                                >
                                  <Icon className="size-3.5" />
                                </button>
                              );
                            })}
                            {paletteEntriesFor(
                              paletteEntries,
                              "host",
                              host,
                            ).map((entry) => {
                              const Icon = entry.icon;
                              return (
                                <button
                                  key={entry.id}
                                  title={t(entry.titleKey)}
                                  onClick={(e) => {
                                    e.stopPropagation();
                                    handleAction(() => entry.run(shell, host));
                                  }}
                                  className="flex items-center justify-center size-7 rounded text-muted-foreground/50 hover:text-foreground hover:bg-muted-foreground/10 transition-colors"
                                >
                                  {Icon && <Icon className="size-3.5" />}
                                </button>
                              );
                            })}
                            {canEditHost(host) && (
                              <>
                                <div className="w-px h-3.5 bg-border/60 mx-0.5 shrink-0" />
                                <button
                                  title={t("hosts.editHost")}
                                  onClick={(e) => {
                                    e.stopPropagation();
                                    setIsOpen(false);
                                    onOpenTab("host-manager");
                                    setTimeout(() => {
                                      window.dispatchEvent(
                                        new CustomEvent(
                                          "host-manager:edit-host",
                                          {
                                            detail: host.id,
                                          },
                                        ),
                                      );
                                    }, 100);
                                  }}
                                  className="flex items-center justify-center size-7 rounded text-muted-foreground/50 hover:text-foreground hover:bg-muted-foreground/10 transition-colors"
                                >
                                  <Pencil className="size-3.5" />
                                </button>
                              </>
                            )}
                          </div>
                        </CommandItem>
                      ))}
                    </div>
                  ))
                ) : (
                  <div className="py-6 text-center text-sm text-muted-foreground">
                    {t("commandPalette.noHostsFound", { search })}
                  </div>
                )}
              </CommandGroup>
            </div>

            <CommandSeparator className="my-2" />

            <CommandGroup heading={t("commandPalette.links")} className="px-2">
              <div className="grid grid-cols-3 gap-1">
                <CommandItem
                  value="link-github"
                  onSelect={() =>
                    window.open(
                      "https://github.com/Termix-SSH/Termix",
                      "_blank",
                    )
                  }
                  className="flex items-center gap-3 px-3 py-2 rounded-none hover:bg-accent-brand/10 cursor-pointer"
                >
                  <Globe className="size-4 text-muted-foreground" />
                  <span className="text-sm font-medium">GitHub</span>
                </CommandItem>
                <CommandItem
                  value="link-discord"
                  onSelect={() =>
                    window.open(
                      "https://discord.com/invite/jVQGdvHDrf",
                      "_blank",
                    )
                  }
                  className="flex items-center gap-3 px-3 py-2 rounded-none hover:bg-accent-brand/10 cursor-pointer"
                >
                  <MessagesSquare className="size-4 text-muted-foreground" />
                  <span className="text-sm font-medium">Discord</span>
                </CommandItem>
                <CommandItem
                  value="link-support"
                  onSelect={() =>
                    window.open(
                      "https://github.com/Termix-SSH/Support/issues/new",
                      "_blank",
                    )
                  }
                  className="flex items-center gap-3 px-3 py-2 rounded-none hover:bg-accent-brand/10 cursor-pointer"
                >
                  <LifeBuoy className="size-4 text-muted-foreground" />
                  <span className="text-sm font-medium">
                    {t("dashboard.support")}
                  </span>
                </CommandItem>
              </div>
            </CommandGroup>
          </CommandList>

          <div className="border-t border-border px-4 py-3 bg-muted/30 flex items-center justify-between text-[11px] text-muted-foreground">
            <div className="flex items-center gap-3">
              <div className="flex items-center gap-1">
                <Kbd className="h-5 px-1 bg-background rounded-none">↑↓</Kbd>
                <span>{t("commandPalette.navigate")}</span>
              </div>
              <div className="flex items-center gap-1">
                <Kbd className="h-5 px-1 bg-background rounded-none">ENTER</Kbd>
                <span>{t("commandPalette.select")}</span>
              </div>
            </div>
            <div className="flex items-center gap-1">
              <span>{t("commandPalette.toggleWith")}</span>
              <Kbd className="h-5 px-1.5 bg-background rounded-none">Ctrl</Kbd>
              <span>+</span>
              <Kbd className="h-5 px-1.5 bg-background rounded-none">K</Kbd>
              <span>{t("commandPalette.orShortcut")}</span>
              <Kbd className="h-5 px-1.5 bg-background rounded-none">Shift</Kbd>
              <span>+</span>
              <Kbd className="h-5 px-1.5 bg-background rounded-none">Shift</Kbd>
            </div>
          </div>
        </Command>
      </div>
    </div>
  );
}