import type { PreferenceKind, PreferenceSuppression, PreferenceTag } from "@umt/contracts";
import { Ban, History, ListChecks, Plus, ShieldOff, Tags } from "lucide-react";
import { useMemo, useState } from "react";
import { Link } from "react-router";
import { toast } from "sonner";
import {
  useDeleteTag,
  useLiftSuppression,
  usePreferenceTags,
  useSuppressions,
  useTagRevisions,
  useUpdateTag,
} from "~/api/preferences.ts";
import { ConfirmDialog } from "~/components/console/confirm-dialog.tsx";
import { DetailSection, DetailSheet } from "~/components/console/detail-sheet.tsx";
import { EmptyState, ErrorState, LoadingState } from "~/components/console/empty-state.tsx";
import { FilterBar, FilterSelect } from "~/components/console/filter-bar.tsx";
import { JsonView } from "~/components/console/json-view.tsx";
import { KvList } from "~/components/console/kv-list.tsx";
import { consolePath } from "~/components/console/nav.ts";
import { PageHeader } from "~/components/console/page-header.tsx";
import { StatusBadge } from "~/components/console/status-badge.tsx";
import { Timeline, type TimelineItem } from "~/components/console/timeline.tsx";
import { MEDIA_KIND, opts, PREF_KIND, PREF_ORIGIN, PREF_STATUS } from "~/components/library/labels.ts";
import { Chip, Panel, relTime, Tone } from "~/components/library/parts.tsx";
import { PreferenceFormDialog } from "~/components/library/preferences-form.tsx";
import { Button } from "~/components/ui/button.tsx";
import { errorMessage } from "~/lib/api.ts";
import { cn, formatDateTime } from "~/lib/utils.ts";

// 偏好标签(REQ §6.7):一个偏好一个标签;停用/删除/改语义留抑制记录,Agent 不据同一旧证据自动加回。

const SUP_REASON: Record<string, string> = {
  deleted: "删除",
  "status:disabled": "停用",
  "status:deleted": "删除",
  edited: "修改语义",
};
const supReason = (r: string | null) => (r ? (SUP_REASON[r] ?? r) : "未注明");
const actorName = (s: string | null) => (s ? s.replace(/^[a-z_]+:/, "") || s : "—");

/** scope 摘要:{} = 全局;mediaKinds 翻中文;其余键原样 */
function scopeSummary(scope: Record<string, unknown>): string {
  const keys = Object.keys(scope);
  if (keys.length === 0) return "全局";
  const parts: string[] = [];
  for (const k of keys) {
    const v = scope[k];
    if (k === "mediaKinds" && Array.isArray(v))
      parts.push(v.map((x) => MEDIA_KIND[x as keyof typeof MEDIA_KIND] ?? String(x)).join("、"));
    else parts.push(`${k}: ${Array.isArray(v) ? v.join("、") : typeof v === "object" ? "…" : String(v)}`);
  }
  return parts.join(" · ");
}

function TagCard({ tag, onOpen }: { tag: PreferenceTag; onOpen: () => void }) {
  const inactive = tag.status !== "active";
  return (
    <button
      type="button"
      onClick={onOpen}
      className={cn(
        "min-w-0 cursor-pointer rounded-xl border border-border/80 bg-foreground/[0.02] p-3 text-left transition-colors duration-micro hover:bg-foreground/[0.05] focus-visible:ring-[3px] focus-visible:ring-ring/50 focus-visible:outline-none",
        inactive && "opacity-70",
      )}
    >
      <div className="flex items-start justify-between gap-2">
        <span className={cn("min-w-0 font-medium break-words text-foreground", inactive && "line-through")}>
          {tag.label}
        </span>
        <Tone v={PREF_STATUS[tag.status]} className="shrink-0" />
      </div>
      <div className="mt-2 flex flex-wrap gap-1.5">
        <Chip>{PREF_KIND[tag.kind].label}</Chip>
        <Chip>{scopeSummary(tag.scope)}</Chip>
        <Chip>{PREF_ORIGIN[tag.origin]}</Chip>
      </div>
      {tag.description ? (
        <p className="mt-2 line-clamp-2 text-meta break-words text-muted-foreground">{tag.description}</p>
      ) : null}
      <p className="mt-2 text-micro text-muted-foreground tabular-nums">
        r{tag.revision} · 更新于 {relTime(tag.updatedAt)}
      </p>
    </button>
  );
}

export default function PreferencesPage() {
  const [status, setStatus] = useState("");
  const [kind, setKind] = useState("");
  const tags = usePreferenceTags({
    status: (status || undefined) as "active" | "disabled" | undefined,
    kind: (kind || undefined) as PreferenceKind | undefined,
  });
  const deleted = usePreferenceTags({ status: "deleted" });
  const allTags = usePreferenceTags({});
  const sups = useSuppressions();
  const [selectedId, setSelectedId] = useState<string | null>(null);
  const [form, setForm] = useState<{ open: boolean; tag: PreferenceTag | null }>({ open: false, tag: null });
  const update = useUpdateTag();
  const del = useDeleteTag();
  const lift = useLiftSuppression();

  const tagById = useMemo(() => {
    const m = new Map<string, PreferenceTag>();
    for (const t of [...(allTags.data?.items ?? []), ...(deleted.data?.items ?? [])]) m.set(t.id, t);
    return m;
  }, [allTags.data, deleted.data]);
  const selected = selectedId ? (tagById.get(selectedId) ?? tags.data?.items.find((t) => t.id === selectedId)) : null;

  const toggle = async (t: PreferenceTag) => {
    const next = t.status === "active" ? "disabled" : "active";
    try {
      await update.mutateAsync({ id: t.id, status: next });
      toast.success(next === "active" ? "已启用,抑制已解除" : "已停用");
    } catch (err) {
      toast.error(errorMessage(err));
    }
  };

  const history = useMemo<TimelineItem[]>(() => {
    const items: (TimelineItem & { ts: number })[] = [];
    for (const s of sups.data?.items ?? []) {
      const label = s.preferenceTagId ? (tagById.get(s.preferenceTagId)?.label ?? "未知标签") : "未关联标签";
      items.push({
        id: `sup-${s.id}`,
        at: s.createdAt,
        ts: Date.parse(s.createdAt),
        tone: "warning",
        title: `「${label}」加入抑制(${supReason(s.reason)})`,
        meta: actorName(s.suppressedBy),
      });
      if (s.liftedAt)
        items.push({
          id: `lift-${s.id}`,
          at: s.liftedAt,
          ts: Date.parse(s.liftedAt),
          tone: "success",
          title: `「${label}」的抑制已解除`,
          meta: actorName(s.liftedBy),
        });
    }
    for (const t of deleted.data?.items ?? []) {
      if ((sups.data?.items ?? []).some((s) => s.preferenceTagId === t.id && s.reason === "deleted")) continue;
      items.push({
        id: `del-${t.id}`,
        at: t.updatedAt,
        ts: Date.parse(t.updatedAt),
        tone: "neutral",
        title: `「${t.label}」已删除`,
      });
    }
    return items.sort((a, b) => b.ts - a.ts).slice(0, 30);
  }, [sups.data, deleted.data, tagById]);

  const activeSups = (sups.data?.items ?? []).filter((s) => s.active);
  const filtered = !!status || !!kind;

  return (
    <>
      <PageHeader
        title="偏好标签"
        description="软偏好影响排序,硬规则直接排除。手动取消的偏好 Agent 不会再加回。"
        actions={
          <>
            <Button asChild variant="ghost" size="sm">
              <Link to={consolePath("rules")}>
                <ListChecks />
                收录策略
              </Link>
            </Button>
            <Button onClick={() => setForm({ open: true, tag: null })}>
              <Plus />
              添加偏好
            </Button>
          </>
        }
      />

      <FilterBar
        onReset={
          filtered
            ? () => {
                setStatus("");
                setKind("");
              }
            : undefined
        }
      >
        <FilterSelect
          label="状态"
          value={status}
          onChange={setStatus}
          allLabel="未删除"
          options={[
            { value: "active", label: "生效中" },
            { value: "disabled", label: "已停用" },
          ]}
        />
        <FilterSelect label="类型" value={kind} onChange={setKind} options={opts(PREF_KIND)} />
      </FilterBar>

      <div className="space-y-6">
        {tags.isPending ? (
          <div className="pg-slab rounded-xl p-4">
            <LoadingState rows={3} />
          </div>
        ) : tags.isError ? (
          <ErrorState error={tags.error} onRetry={() => tags.refetch()} />
        ) : tags.data.items.length === 0 ? (
          <EmptyState
            icon={Tags}
            title={filtered ? "没有符合条件的偏好" : "还没有偏好标签"}
            description="点「添加偏好」,或在 Agent 会话里说明长期偏好。"
          />
        ) : (
          <Panel title="偏好" description={`${tags.data.items.length} 个标签`}>
            <div className="grid gap-3 sm:grid-cols-2 lg:grid-cols-3">
              {tags.data.items.map((t) => (
                <TagCard key={t.id} tag={t} onOpen={() => setSelectedId(t.id)} />
              ))}
            </div>
          </Panel>
        )}

        <Panel title="抑制记录" description={`${activeSups.length} 条生效中`} bodyClassName="space-y-3">
          <div className="flex gap-2 rounded-lg border border-warning/30 bg-warning/10 px-3 py-2 text-caption text-foreground">
            <ShieldOff className="mt-0.5 h-4 w-4 shrink-0 text-warning" />
            <p>停用、删除或修改语义的偏好会留下抑制记录,Agent 不会按旧证据加回。重新启用、重新添加或解除抑制后恢复。</p>
          </div>
          {sups.isPending ? (
            <LoadingState rows={2} />
          ) : sups.isError ? (
            <ErrorState plain error={sups.error} onRetry={() => sups.refetch()} />
          ) : sups.data.items.length === 0 ? (
            <EmptyState plain icon={Ban} title="没有抑制记录" className="py-8" />
          ) : (
            <ul className="divide-y divide-border/60">
              {sups.data.items.map((s) => (
                <SuppressionRow
                  key={s.id}
                  s={s}
                  label={s.preferenceTagId ? tagById.get(s.preferenceTagId)?.label : undefined}
                  onLift={async () => {
                    try {
                      await lift.mutateAsync({ id: s.id, reason: "用户明确解除" });
                      toast.success("已解除抑制");
                    } catch (err) {
                      toast.error(errorMessage(err));
                      throw err;
                    }
                  }}
                />
              ))}
            </ul>
          )}
        </Panel>

        <Panel title="历史" description="停用、删除、解除抑制(新 → 旧)">
          {sups.isPending || deleted.isPending ? (
            <LoadingState rows={2} />
          ) : history.length === 0 ? (
            <EmptyState plain icon={History} title="还没有变更历史" className="py-8" />
          ) : (
            <Timeline items={history} />
          )}
        </Panel>
      </div>

      <DetailSheet
        open={!!selected}
        onOpenChange={(o) => !o && setSelectedId(null)}
        title={selected?.label ?? ""}
        description={selected ? `${PREF_KIND[selected.kind].label} · ${PREF_KIND[selected.kind].hint}` : undefined}
        footer={
          selected && selected.status !== "deleted" ? (
            <>
              <ConfirmDialog
                trigger={<Button variant="destructive">删除</Button>}
                title={`删除「${selected.label}」?`}
                description="删除后留下抑制记录,Agent 不会按旧证据加回。"
                confirmLabel="删除"
                destructive
                onConfirm={async () => {
                  try {
                    await del.mutateAsync(selected.id);
                    toast.success("已删除");
                    setSelectedId(null);
                  } catch (err) {
                    toast.error(errorMessage(err));
                    throw err;
                  }
                }}
              />
              <Button variant="outline" onClick={() => toggle(selected)} disabled={update.isPending}>
                {selected.status === "active" ? "停用" : "重新启用"}
              </Button>
              <Button onClick={() => setForm({ open: true, tag: selected })}>编辑</Button>
            </>
          ) : undefined
        }
      >
        {selected ? (
          <>
            <KvList
              items={[
                { label: "状态", value: <Tone v={PREF_STATUS[selected.status]} /> },
                { label: "来源", value: PREF_ORIGIN[selected.origin] },
                { label: "作用范围", value: scopeSummary(selected.scope) },
                { label: "修订", value: `r${selected.revision}` },
                { label: "创建", value: formatDateTime(selected.createdAt) },
                { label: "更新", value: formatDateTime(selected.updatedAt) },
                { label: "说明", value: selected.description, wide: true },
                { label: "语义指纹", value: selected.fingerprint, mono: true, wide: true },
              ]}
            />
            <DetailSection title="规则">
              <JsonView value={selected.rule} />
            </DetailSection>
            <DetailSection title="作用范围">
              <JsonView value={selected.scope} />
            </DetailSection>
            <DetailSection title="证据">
              <JsonView value={Object.keys(selected.evidence).length ? selected.evidence : null} />
            </DetailSection>
            <DetailSection title="修订历史">
              <TagRevisions id={selected.id} />
            </DetailSection>
          </>
        ) : null}
      </DetailSheet>

      <PreferenceFormDialog open={form.open} tag={form.tag} onOpenChange={(o) => setForm((f) => ({ ...f, open: o }))} />
    </>
  );
}

const REV_ACTION = { created: "创建", updated: "修改", deleted: "删除" } as const;
const FIELD_LABEL: Record<string, string> = {
  label: "名称",
  kind: "类型",
  scope: "作用范围",
  rule: "规则",
  description: "说明",
  evidence: "证据",
  status: "状态",
};

function TagRevisions({ id }: { id: string }) {
  const q = useTagRevisions(id);
  if (q.isPending) return <LoadingState rows={2} />;
  if (q.isError) return <ErrorState plain error={q.error} onRetry={() => q.refetch()} />;
  if (q.data.length === 0)
    return <p className="text-caption text-muted-foreground">没有修订记录。W4 之前创建的标签没有历史。</p>;
  return (
    <ul className="space-y-2">
      {q.data.map((r) => (
        <li key={r.id} className="rounded-lg border border-border/70 px-3 py-2 text-caption">
          <div className="flex flex-wrap items-center gap-2">
            <span className="font-medium text-foreground">{REV_ACTION[r.action]}</span>
            {r.revision ? <span className="text-muted-foreground tabular-nums">r{r.revision}</span> : null}
            <span className="text-muted-foreground">{r.actorType === "api_key" ? "API Key" : "用户"}</span>
            <span className="ml-auto text-meta text-muted-foreground tabular-nums">{formatDateTime(r.at)}</span>
          </div>
          <p className="mt-1 text-meta text-muted-foreground">
            {r.changedFields.length
              ? `改动:${r.changedFields.map((f) => FIELD_LABEL[f] ?? f).join("、")}`
              : `名称:${r.snapshot.label} · 状态:${r.snapshot.status}`}
          </p>
        </li>
      ))}
    </ul>
  );
}

function SuppressionRow({
  s,
  label,
  onLift,
}: {
  s: PreferenceSuppression;
  label: string | undefined;
  onLift: () => Promise<void>;
}) {
  return (
    <li className="flex flex-wrap items-center gap-x-3 gap-y-1 py-2.5">
      <div className="min-w-0 flex-1">
        <div className="flex flex-wrap items-center gap-2">
          <span className="min-w-0 font-medium break-words text-foreground">{label ?? "未关联标签"}</span>
          <Chip>{supReason(s.reason)}</Chip>
          {s.active ? <StatusBadge tone="warning">抑制中</StatusBadge> : <StatusBadge>已解除</StatusBadge>}
        </div>
        <p className="mt-0.5 text-meta text-muted-foreground tabular-nums">
          {actorName(s.suppressedBy)} · {formatDateTime(s.createdAt)}
          {s.liftedAt ? ` · ${actorName(s.liftedBy)} 于 ${formatDateTime(s.liftedAt)} 解除` : ""}
        </p>
      </div>
      {s.active ? (
        <ConfirmDialog
          trigger={
            <Button variant="outline" size="sm">
              解除抑制
            </Button>
          }
          title="解除这条抑制?"
          description="解除后,Agent 可按证据再次提出这个偏好,仍需授权。标签不会恢复。"
          confirmLabel="解除"
          onConfirm={onLift}
        />
      ) : null}
    </li>
  );
}