import type { SearchSiteMode, Site } from "@umt/contracts";
import { PackageSearch } from "lucide-react";
import { useEffect, useMemo, useState } from "react";
import { Link } from "react-router";
import { useSiteOptions } from "~/api/instances.ts";
import { useSettings } from "~/api/settings.ts";
import { consolePath } from "~/components/console/nav.ts";
import { ChipToggleGroup } from "~/components/library/parts.tsx";
import { Button } from "~/components/ui/button.tsx";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "~/components/ui/dialog.tsx";
import { cn } from "~/lib/utils.ts";

// 搜资源前选站点:默认(站点页勾了「默认参与搜索」的)/ 全部启用站点 / 指定站点。
// 初始值 = 本机上次的选择,没有就用 settings.search.defaultSiteMode。

export type SitePick = { mode: SearchSiteMode; siteIds: string[] };

const STORE_KEY = "umt.search.sitePick";

export function loadSitePick(): SitePick | null {
  try {
    const raw = globalThis.localStorage?.getItem(STORE_KEY);
    if (!raw) return null;
    const v = JSON.parse(raw) as Partial<SitePick>;
    if (v.mode !== "default" && v.mode !== "all" && v.mode !== "custom") return null;
    return { mode: v.mode, siteIds: Array.isArray(v.siteIds) ? v.siteIds.filter((x) => typeof x === "string") : [] };
  } catch {
    return null;
  }
}

function saveSitePick(p: SitePick) {
  try {
    globalThis.localStorage?.setItem(STORE_KEY, JSON.stringify(p));
  } catch {
    // 隐私模式等存不了:只是下次不记得
  }
}

/** 按模式解析出站点 ID(只含启用站点) */
export function resolvePick(pick: SitePick, sites: Pick<Site, "id" | "enabled" | "searchDefault">[]): string[] {
  const on = sites.filter((s) => s.enabled);
  if (pick.mode === "all") return on.map((s) => s.id);
  if (pick.mode === "custom") {
    const set = new Set(pick.siteIds);
    return on.filter((s) => set.has(s.id)).map((s) => s.id);
  }
  return on.filter((s) => s.searchDefault !== false).map((s) => s.id);
}

const MODES: { value: SearchSiteMode; label: string }[] = [
  { value: "default", label: "默认站点" },
  { value: "all", label: "全部站点" },
  { value: "custom", label: "指定站点" },
];

export function SitePickerDialog({
  open,
  onOpenChange,
  title,
  onConfirm,
}: {
  open: boolean;
  onOpenChange: (o: boolean) => void;
  /** 作品名,显示在说明里 */
  title: string;
  onConfirm: (siteIds: string[]) => void;
}) {
  const sitesQ = useSiteOptions();
  const settings = useSettings();
  const sites = useMemo(
    () => (sitesQ.data?.items ?? []).filter((s) => s.enabled && s.capabilities.includes("search")),
    [sitesQ.data],
  );
  const [pick, setPick] = useState<SitePick | null>(null);
  // 打开时取初始值:本机上次 > 全局设置 > 默认
  useEffect(() => {
    if (!open) return;
    const cfg = settings.data?.search;
    setPick(
      loadSitePick() ?? (cfg ? { mode: cfg.defaultSiteMode, siteIds: cfg.siteIds } : { mode: "default", siteIds: [] }),
    );
  }, [open, settings.data]);

  const cur = pick ?? { mode: "default" as const, siteIds: [] };
  const ids = resolvePick(cur, sites);
  const count = (m: SearchSiteMode) => resolvePick({ mode: m, siteIds: cur.siteIds }, sites).length;

  const confirm = () => {
    saveSitePick(cur);
    onConfirm(ids);
    onOpenChange(false);
  };

  return (
    <Dialog open={open} onOpenChange={onOpenChange}>
      <DialogContent className="sm:max-w-lg">
        <DialogHeader>
          <DialogTitle>搜索资源</DialogTitle>
          <DialogDescription>在所选站点搜「{title}」。每个站点按作品原名和译名各查一次。</DialogDescription>
        </DialogHeader>
        <fieldset aria-label="站点范围" className="m-0 grid grid-cols-3 gap-1 rounded-lg border border-border/70 p-1">
          {MODES.map((m) => (
            <button
              key={m.value}
              type="button"
              aria-pressed={cur.mode === m.value}
              onClick={() =>
                setPick({
                  mode: m.value,
                  // 切到「指定」时从当前集合起步
                  siteIds: m.value === "custom" && cur.mode !== "custom" ? ids : cur.siteIds,
                })
              }
              className={cn(
                "cursor-pointer rounded-md px-2 py-1.5 text-caption transition-colors duration-micro",
                cur.mode === m.value
                  ? "bg-foreground/[0.08] font-medium text-foreground"
                  : "text-muted-foreground hover:text-foreground",
              )}
            >
              {m.label}
              {m.value !== "custom" && sitesQ.data ? (
                <span className="ml-1 text-meta text-muted-foreground tabular-nums">{count(m.value)}</span>
              ) : null}
            </button>
          ))}
        </fieldset>
        {sitesQ.isPending ? (
          <p className="text-caption text-muted-foreground">加载站点…</p>
        ) : sites.length === 0 ? (
          <p className="text-caption text-muted-foreground">
            还没有启用的站点。
            <Link to={consolePath("sites")} className="ml-1 underline underline-offset-4">
              去站点页
            </Link>
          </p>
        ) : cur.mode === "custom" ? (
          <ChipToggleGroup
            label="站点"
            options={sites.map((s) => ({ value: s.id, label: s.name }))}
            value={cur.siteIds.filter((id) => sites.some((s) => s.id === id))}
            onChange={(v) => setPick({ mode: "custom", siteIds: v })}
          />
        ) : (
          <p className="text-caption break-words text-muted-foreground">
            {ids.length
              ? sites
                  .filter((s) => ids.includes(s.id))
                  .map((s) => s.name)
                  .join("、")
              : "没有站点勾选「默认参与搜索」。在站点页打开，或改选全部站点。"}
          </p>
        )}
        <DialogFooter>
          <Button variant="outline" onClick={() => onOpenChange(false)}>
            取消
          </Button>
          <Button onClick={confirm} disabled={ids.length === 0}>
            <PackageSearch />
            搜索 {ids.length} 个站点
          </Button>
        </DialogFooter>
      </DialogContent>
    </Dialog>
  );
}