편의 기능(정렬·종류필터·전체선택/단축키·정보 오버레이) + 스냅샷 범위 안전화

Snapshot 접근자 범위 안전화(핵심 버그):
- id/width/height/kind/hasThumb/thumbFailed가 count 밖 i에서 DataView RangeError를
  던져 Solid 반응성 그래프 전체가 무너지던 문제 수정. 스냅샷이 줄어들 때(필터/검색/
  폴더 전환) For가 초과 셀을 제거하기 전에 셀 접근자가 옛 인덱스로 재실행되며 발생.
  범위 밖이면 0/false 반환. (증상: 필터/검색이 한 번은 되고 이후 먹통)

기능:
- 정렬: 촬영일/이름/크기/수정일 × 오름·내림 (툴바 드롭다운+방향 토글).
  backend snap_tail로 ORDER BY 구성, 4개 스냅샷 커맨드에 sort/kind 파라미터 추가.
- 종류 필터: 전체/사진/영상 툴바 토글 (backend kind 필터).
- 전체 선택(Ctrl+A)/선택 반전(Ctrl+Shift+A), ? 키 단축키 도움말 오버레이.
- 썸네일 정보 오버레이(ⓘ 토글): 가시 셀에 파일명·크기 지연 로드 표시.

검증(사진120+영상25): 종류필터 120/25/145/120 반복 정상, 정렬 순서 변경, Ctrl+A
145개 선택, ? 오버레이, ⓘ로 파일명 표시 확인.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src-tauri/src/commands.rs

@@ -373,7 +373,32 @@ fn pack_snapshot(rows: Vec<(i64, Option<u32>, Option<u32>, Option<u32>, i64, i64
 
 type SnapRow = (i64, Option<u32>, Option<u32>, Option<u32>, i64, i64);
 const SNAP_COLS: &str = "f.id, f.width, f.height, f.orientation, f.kind, f.thumb_state";
-const SNAP_ORDER: &str = "ORDER BY COALESCE(f.taken_at, f.mtime_ms) DESC, f.id DESC";
+
+/// 스냅샷 공통 옵션 — 종류 필터 + 정렬. 프론트 툴바에서 전달.
+#[derive(Default)]
+pub struct SnapOpts {
+    pub sort_key: Option<String>, // taken(기본)|name|size|mtime
+    pub sort_desc: Option<bool>,  // 기본 내림차순
+    pub kind: Option<i64>,        // 0=사진, 1=영상, 그 외/None=전체
+}
+
+/// WHERE 꼬리(종류 필터) + ORDER BY 절을 만든다.
+/// sort_key/kind는 고정 집합에서만 해석하므로 SQL 주입 안전(kind는 i64 리터럴).
+fn snap_tail(o: &SnapOpts) -> String {
+    let kind_clause = match o.kind {
+        Some(0) => " AND f.kind = 0",
+        Some(1) => " AND f.kind = 1",
+        _ => "",
+    };
+    let dir = if o.sort_desc.unwrap_or(true) { "DESC" } else { "ASC" };
+    let order = match o.sort_key.as_deref() {
+        Some("name") => format!("ORDER BY f.name COLLATE NOCASE {dir}, f.id {dir}"),
+        Some("size") => format!("ORDER BY f.size {dir}, f.id {dir}"),
+        Some("mtime") => format!("ORDER BY f.mtime_ms {dir}, f.id {dir}"),
+        _ => format!("ORDER BY COALESCE(f.taken_at, f.mtime_ms) {dir}, f.id {dir}"),
+    };
+    format!("{kind_clause} {order}")
+}
 
 fn map_snap_row(r: &rusqlite::Row<'_>) -> rusqlite::Result<SnapRow> {
     Ok((r.get(0)?, r.get(1)?, r.get(2)?, r.get(3)?, r.get(4)?, r.get(5)?))
@@ -385,7 +410,11 @@ pub fn folder_snapshot(
     source_id: Option<i64>,
     folder_id: Option<i64>,
     recursive: bool,
+    sort_key: Option<String>,
+    sort_desc: Option<bool>,
+    kind: Option<i64>,
 ) -> CmdResult<Response> {
+    let tail = snap_tail(&SnapOpts { sort_key, sort_desc, kind });
     let rows: Vec<SnapRow> = state
         .db
         .with_read(|conn| {
@@ -393,7 +422,7 @@ pub fn folder_snapshot(
                 (Some(fid), false) => {
                     let sql = format!(
                         "SELECT {SNAP_COLS} FROM files f
-                         WHERE f.folder_id = ?1 AND f.deleted_at IS NULL {SNAP_ORDER}"
+                         WHERE f.folder_id = ?1 AND f.deleted_at IS NULL {tail}"
                     );
                     let mut stmt = conn.prepare_cached(&sql)?;
                     let rows = stmt.query_map([fid], |r| map_snap_row(r))?;
@@ -411,7 +440,7 @@ pub fn folder_snapshot(
                         "SELECT {SNAP_COLS} FROM files f
                          JOIN folders fo ON fo.id = f.folder_id
                          WHERE fo.source_id = ?1 AND (fo.path = ?2 OR fo.path LIKE ?3)
-                           AND f.deleted_at IS NULL {SNAP_ORDER}"
+                           AND f.deleted_at IS NULL {tail}"
                     );
                     let mut stmt = conn.prepare_cached(&sql)?;
                     let rows =
@@ -422,7 +451,7 @@ pub fn folder_snapshot(
                     Some(sid) => {
                         let sql = format!(
                             "SELECT {SNAP_COLS} FROM files f
-                             WHERE f.source_id = ?1 AND f.deleted_at IS NULL {SNAP_ORDER}"
+                             WHERE f.source_id = ?1 AND f.deleted_at IS NULL {tail}"
                         );
                         let mut stmt = conn.prepare_cached(&sql)?;
                         let rows = stmt.query_map([sid], |r| map_snap_row(r))?;
@@ -431,7 +460,7 @@ pub fn folder_snapshot(
                     None => {
                         let sql = format!(
                             "SELECT {SNAP_COLS} FROM files f
-                             WHERE f.deleted_at IS NULL {SNAP_ORDER}"
+                             WHERE f.deleted_at IS NULL {tail}"
                         );
                         let mut stmt = conn.prepare_cached(&sql)?;
                         let rows = stmt.query_map([], |r| map_snap_row(r))?;
@@ -445,11 +474,18 @@ pub fn folder_snapshot(
 }
 
 #[tauri::command]
-pub fn search_snapshot(state: tauri::State<'_, AppState>, query: String) -> CmdResult<Response> {
+pub fn search_snapshot(
+    state: tauri::State<'_, AppState>,
+    query: String,
+    sort_key: Option<String>,
+    sort_desc: Option<bool>,
+    kind: Option<i64>,
+) -> CmdResult<Response> {
     let q = query.trim().to_string();
     if q.is_empty() {
         return Ok(Response::new(Vec::new()));
     }
+    let tail = snap_tail(&SnapOpts { sort_key, sort_desc, kind });
     let use_fts = state.db.fts_enabled && q.chars().count() >= 3;
     let rows: Vec<SnapRow> = state
         .db
@@ -458,7 +494,7 @@ pub fn search_snapshot(state: tauri::State<'_, AppState>, query: String) -> CmdR
                 let sql = format!(
                     "SELECT {SNAP_COLS} FROM files_fts ft
                      JOIN files f ON f.id = ft.rowid
-                     WHERE files_fts MATCH ?1 AND f.deleted_at IS NULL {SNAP_ORDER}"
+                     WHERE files_fts MATCH ?1 AND f.deleted_at IS NULL {tail}"
                 );
                 let mut stmt = conn.prepare_cached(&sql)?;
                 // MATCH 구문 특수문자 무력화를 위해 따옴표로 감싼다
@@ -468,7 +504,7 @@ pub fn search_snapshot(state: tauri::State<'_, AppState>, query: String) -> CmdR
             } else {
                 let sql = format!(
                     "SELECT {SNAP_COLS} FROM files f
-                     WHERE f.name LIKE '%' || ?1 || '%' ESCAPE '\\' AND f.deleted_at IS NULL {SNAP_ORDER}"
+                     WHERE f.name LIKE '%' || ?1 || '%' ESCAPE '\\' AND f.deleted_at IS NULL {tail}"
                 );
                 let mut stmt = conn.prepare_cached(&sql)?;
                 let escaped = q.replace('\\', "\\\\").replace('%', "\\%").replace('_', "\\_");
@@ -619,14 +655,21 @@ pub fn export_tags(state: tauri::State<'_, AppState>, path: Option<String>) -> C
 }
 
 #[tauri::command]
-pub fn tag_snapshot(state: tauri::State<'_, AppState>, tag_id: i64) -> CmdResult<Response> {
+pub fn tag_snapshot(
+    state: tauri::State<'_, AppState>,
+    tag_id: i64,
+    sort_key: Option<String>,
+    sort_desc: Option<bool>,
+    kind: Option<i64>,
+) -> CmdResult<Response> {
+    let tail = snap_tail(&SnapOpts { sort_key, sort_desc, kind });
     let rows: Vec<SnapRow> = state
         .db
         .with_read(|conn| {
             let sql = format!(
                 "SELECT {SNAP_COLS} FROM files f
                  JOIN file_tags ft ON ft.file_id = f.id
-                 WHERE ft.tag_id = ?1 AND f.deleted_at IS NULL {SNAP_ORDER}"
+                 WHERE ft.tag_id = ?1 AND f.deleted_at IS NULL {tail}"
             );
             let mut stmt = conn.prepare_cached(&sql)?;
             let rows = stmt.query_map([tag_id], |r| map_snap_row(r))?;
@@ -797,7 +840,14 @@ pub fn delete_smart_folder(state: tauri::State<'_, AppState>, id: i64) -> CmdRes
 }
 
 #[tauri::command]
-pub fn smart_snapshot(state: tauri::State<'_, AppState>, id: i64) -> CmdResult<Response> {
+pub fn smart_snapshot(
+    state: tauri::State<'_, AppState>,
+    id: i64,
+    sort_key: Option<String>,
+    sort_desc: Option<bool>,
+    kind: Option<i64>,
+) -> CmdResult<Response> {
+    let tail = snap_tail(&SnapOpts { sort_key, sort_desc, kind });
     let query: SmartQuery = state
         .db
         .with_read(|conn| {
@@ -834,7 +884,7 @@ pub fn smart_snapshot(state: tauri::State<'_, AppState>, id: i64) -> CmdResult<R
     let rows: Vec<SnapRow> = state
         .db
         .with_read(|conn| {
-            let sql = format!("SELECT {SNAP_COLS} FROM files f WHERE {where_sql} {SNAP_ORDER}");
+            let sql = format!("SELECT {SNAP_COLS} FROM files f WHERE {where_sql} {tail}");
             let mut stmt = conn.prepare(&sql)?;
             let rows = stmt.query_map([], |r| map_snap_row(r))?;
             rows.collect()

src/App.tsx

@@ -8,6 +8,7 @@ import { ContextMenu } from "./features/fileops/ContextMenu";
 import { MoveDialog } from "./features/fileops/MoveDialog";
 import { DedupePanel } from "./features/dedupe/DedupePanel";
 import { RemoteDialog } from "./features/sources/RemoteDialog";
+import { ShortcutsOverlay } from "./shell/ShortcutsOverlay";
 import { onLibraryChanged, onThumbsReady, type UnlistenFn } from "./ipc/commands";
 import { bumpThumbVersions, loadAppInfo, refreshPendingCounts, refreshSnapshot } from "./state/store";
 
@@ -45,6 +46,7 @@ const App: Component = () => {
       <MoveDialog />
       <DedupePanel />
       <RemoteDialog />
+      <ShortcutsOverlay />
     </div>
   );
 };

src/features/grid/JustifiedGrid.tsx

@@ -10,6 +10,7 @@ import {
   Show,
   type Component,
 } from "solid-js";
+import { createStore, produce } from "solid-js/store";
 import { computeLayout, type LayoutResult } from "./layout";
 import {
   anchorIndex,
@@ -17,9 +18,11 @@ import {
   gridRowHeight,
   info,
   openLightbox,
+  openShortcuts,
   selected,
   selectSingle,
   setSelectionFromIds,
+  showInfo,
   toggleSelect,
   selectRange,
   snapshot,
@@ -38,6 +41,12 @@ import {
 const GAP = 6;
 const OVERSCAN_PX = 800;
 
+function fmtSize(bytes: number): string {
+  if (bytes >= 1 << 20) return `${(bytes / (1 << 20)).toFixed(1)}MB`;
+  if (bytes >= 1 << 10) return `${(bytes / (1 << 10)).toFixed(0)}KB`;
+  return `${bytes}B`;
+}
+
 /** rowTops에서 y 이상이 처음 나오는 행 인덱스 (이진탐색) */
 function findRow(rowTops: Float32Array, y: number): number {
   let lo = 0;
@@ -156,6 +165,35 @@ export const JustifiedGrid: Component = () => {
   });
   onCleanup(() => clearTimeout(prioTimer));
 
+  // 정보 오버레이용 파일명/크기 지연 로드 (showInfo 켜졌을 때 가시 범위만)
+  const [detailsCache, setDetailsCache] = createStore<Record<number, { name: string; size: number }>>({});
+  let detTimer: ReturnType<typeof setTimeout> | undefined;
+  createEffect(() => {
+    if (!showInfo()) return;
+    const [first, last] = visibleRange();
+    const snap = snapshot();
+    if (!snap || last < first) return;
+    clearTimeout(detTimer);
+    detTimer = setTimeout(() => {
+      const need: number[] = [];
+      for (let i = first; i <= last && need.length < 512; i++) {
+        const id = snap.id(i);
+        if (detailsCache[id] === undefined) need.push(id);
+      }
+      if (need.length === 0) return;
+      void fileDetails(need)
+        .then((ds) =>
+          setDetailsCache(
+            produce((s) => {
+              for (const d of ds) s[d.id] = { name: d.name, size: d.size };
+            }),
+          ),
+        )
+        .catch(() => {});
+    }, 150);
+  });
+  onCleanup(() => clearTimeout(detTimer));
+
   const indices = createMemo(() => {
     const [first, last] = visibleRange();
     const out: number[] = [];
@@ -206,6 +244,25 @@ export const JustifiedGrid: Component = () => {
       void performUndo();
       return;
     }
+    // Ctrl+A 전체 선택 / Ctrl+Shift+A 선택 반전
+    if ((e.ctrlKey || e.metaKey) && e.key.toLowerCase() === "a") {
+      e.preventDefault();
+      const all: number[] = [];
+      for (let i = 0; i < snap.count; i++) all.push(snap.id(i));
+      if (e.shiftKey) {
+        const cur = selected();
+        setSelectionFromIds(all.filter((id) => !cur.has(id)));
+      } else {
+        setSelectionFromIds(all);
+      }
+      return;
+    }
+    // ? 단축키 도움말
+    if (e.key === "?") {
+      e.preventDefault();
+      openShortcuts();
+      return;
+    }
 
     switch (e.key) {
       case "Enter":
@@ -456,6 +513,15 @@ export const JustifiedGrid: Component = () => {
                       영상
                     </span>
                   </Show>
+                  {/* 파일명·크기 오버레이 (툴바 ⓘ 토글) */}
+                  <Show when={showInfo()}>
+                    <div class="pointer-events-none absolute inset-x-0 bottom-0 bg-black/55 px-1 py-0.5 leading-tight">
+                      <div class="truncate text-[10px] text-white/90">{detailsCache[id()]?.name ?? ""}</div>
+                      <Show when={detailsCache[id()]}>
+                        <div class="text-[9px] text-white/60">{fmtSize(detailsCache[id()]!.size)}</div>
+                      </Show>
+                    </div>
+                  </Show>
                 </div>
               );
             }}

src/i18n/ko.ts

@@ -28,6 +28,38 @@ export const ko = {
     empty: "표시할 항목이 없습니다",
     items: (n: number) => `${n.toLocaleString("ko-KR")}개 항목`,
     selected: (n: number) => `${n.toLocaleString("ko-KR")}개 선택됨`,
+    infoToggle: "썸네일에 파일명·크기 표시",
+  },
+  filter: {
+    all: "전체",
+    image: "사진",
+    video: "영상",
+  },
+  sort: {
+    taken: "촬영일",
+    name: "이름",
+    size: "크기",
+    mtime: "수정일",
+    asc: "오름차순",
+    desc: "내림차순",
+  },
+  shortcuts: {
+    title: "키보드 단축키",
+    close: "닫기 (Esc / ?)",
+    items: [
+      ["Space / K", "재생·일시정지 (영상)"],
+      ["← →", "이전·다음 항목 (그리드) / 5초 이동 (영상)"],
+      ["↑ ↓", "위·아래 줄 이동 (그리드) / 볼륨 (영상)"],
+      ["Enter / Space", "선택 항목 크게 보기"],
+      ["Ctrl+A", "전체 선택"],
+      ["Ctrl+Shift+A", "선택 반전"],
+      ["Esc", "선택 해제 / 닫기"],
+      ["Delete", "휴지통으로"],
+      ["Ctrl+Z", "실행 취소"],
+      ["F2", "이름 바꾸기"],
+      ["Ctrl+휠", "썸네일 크기"],
+      ["?", "이 도움말"],
+    ] as [string, string][],
   },
   details: {
     title: "상세 정보",

src/ipc/commands.ts

@@ -88,24 +88,30 @@ export class Snapshot {
     this.view = new DataView(buf);
     this.count = Math.floor(buf.byteLength / ITEM_BYTES);
   }
+  // 모든 접근자는 범위 밖 i에 안전해야 한다. 스냅샷이 줄어들 때(필터/검색/폴더 전환)
+  // For가 초과 셀을 제거하기 전에 셀의 반응형 접근자가 옛 인덱스로 재실행될 수 있는데,
+  // DataView가 범위를 벗어나면 RangeError를 던져 Solid 반응성 그래프 전체가 무너진다.
+  private ok(i: number): boolean {
+    return i >= 0 && i < this.count;
+  }
   id(i: number): number {
-    return this.view.getUint32(i * ITEM_BYTES, true);
+    return this.ok(i) ? this.view.getUint32(i * ITEM_BYTES, true) : 0;
   }
   width(i: number): number {
-    return this.view.getUint16(i * ITEM_BYTES + 4, true);
+    return this.ok(i) ? this.view.getUint16(i * ITEM_BYTES + 4, true) : 0;
   }
   height(i: number): number {
-    return this.view.getUint16(i * ITEM_BYTES + 6, true);
+    return this.ok(i) ? this.view.getUint16(i * ITEM_BYTES + 6, true) : 0;
   }
   kind(i: number): number {
-    return this.view.getUint8(i * ITEM_BYTES + 8);
+    return this.ok(i) ? this.view.getUint8(i * ITEM_BYTES + 8) : 0;
   }
   hasThumb(i: number): boolean {
-    return (this.view.getUint8(i * ITEM_BYTES + 9) & 1) !== 0;
+    return this.ok(i) && (this.view.getUint8(i * ITEM_BYTES + 9) & 1) !== 0;
   }
   /** 썸네일 생성을 시도했으나 실패함(state 2) — 대기와 구분해 스켈레톤을 멈추기 위함 */
   thumbFailed(i: number): boolean {
-    return (this.view.getUint8(i * ITEM_BYTES + 9) & 2) !== 0;
+    return this.ok(i) && (this.view.getUint8(i * ITEM_BYTES + 9) & 2) !== 0;
   }
   /** 레이아웃 워커 입력용 종횡비 배열 (미지 치수는 1:1) */
   aspectRatios(): Float32Array {
@@ -119,21 +125,34 @@ export class Snapshot {
   }
 }
 
-export async function folderSnapshot(args: {
+/** 정렬 키: taken(촬영/기본) | name | size | mtime */
-  sourceId?: number;
+export type SortKey = "taken" | "name" | "size" | "mtime";
-  folderId?: number;
+/** 스냅샷 공통 옵션 — 정렬/종류 필터 */
-  recursive?: boolean;
+export interface SnapOpts {
-}): Promise<Snapshot> {
+  sortKey?: SortKey;
+  sortDesc?: boolean;
+  kind?: number | null; // 0=사진, 1=영상, null=전체
+}
+const snapArgs = (o?: SnapOpts) => ({
+  sortKey: o?.sortKey ?? null,
+  sortDesc: o?.sortDesc ?? null,
+  kind: o?.kind ?? null,
+});
+
+export async function folderSnapshot(
+  args: { sourceId?: number; folderId?: number; recursive?: boolean } & SnapOpts,
+): Promise<Snapshot> {
   const buf = await invoke<ArrayBuffer>("folder_snapshot", {
     sourceId: args.sourceId ?? null,
     folderId: args.folderId ?? null,
     recursive: args.recursive ?? true,
+    ...snapArgs(args),
   });
   return new Snapshot(buf);
 }
 
-export async function searchSnapshot(query: string): Promise<Snapshot> {
+export async function searchSnapshot(query: string, opts?: SnapOpts): Promise<Snapshot> {
-  const buf = await invoke<ArrayBuffer>("search_snapshot", { query });
+  const buf = await invoke<ArrayBuffer>("search_snapshot", { query, ...snapArgs(opts) });
   return new Snapshot(buf);
 }
 
@@ -165,8 +184,8 @@ export const fileTagsOf = (fileId: number) => invoke<Tag[]>("file_tags_of", { fi
 export const exportTags = (path?: string) =>
   invoke<string>("export_tags", { path: path ?? null });
 
-export async function tagSnapshot(tagId: number): Promise<Snapshot> {
+export async function tagSnapshot(tagId: number, opts?: SnapOpts): Promise<Snapshot> {
-  return new Snapshot(await invoke<ArrayBuffer>("tag_snapshot", { tagId }));
+  return new Snapshot(await invoke<ArrayBuffer>("tag_snapshot", { tagId, ...snapArgs(opts) }));
 }
 
 // ── 파일 작업 ───────────────────────────────────────────
@@ -227,8 +246,8 @@ export const createSmartFolder = (name: string, query: SmartQuery) =>
 export const deleteSmartFolder = (id: number) =>
   invoke<void>("delete_smart_folder", { id });
 
-export async function smartSnapshot(id: number): Promise<Snapshot> {
+export async function smartSnapshot(id: number, opts?: SnapOpts): Promise<Snapshot> {
-  return new Snapshot(await invoke<ArrayBuffer>("smart_snapshot", { id }));
+  return new Snapshot(await invoke<ArrayBuffer>("smart_snapshot", { id, ...snapArgs(opts) }));
 }
 
 // ── 원격 소스 ───────────────────────────────────────────

src/shell/ContentArea.tsx

@@ -1,4 +1,4 @@
-import { createResource, createSignal, onCleanup, Show, type Component } from "solid-js";
+import { createResource, createSignal, For, onCleanup, Show, type Component } from "solid-js";
 import { open } from "@tauri-apps/plugin-dialog";
 import { ko } from "../i18n/ko";
 import { JustifiedGrid } from "../features/grid/JustifiedGrid";
@@ -6,13 +6,22 @@ import {
   GRID_ROW_MAX,
   GRID_ROW_MIN,
   gridRowHeight,
+  kindFilter,
   refreshSidebar,
   setGridRowHeight,
+  setKindFilter,
+  setSort,
   setView,
+  showInfo,
   sidebarVersion,
   snapshot,
+  sortDesc,
+  sortKey,
+  toggleShowInfo,
   updateScanProgress,
   view,
+  type KindFilter,
+  type SortKey,
 } from "../state/store";
 import { addLocalSource, listSources, startScan } from "../ipc/commands";
 import { openRemoteDialog } from "../features/sources/RemoteDialog";
@@ -61,6 +70,58 @@ export const ContentArea: Component = () => {
         <span class="text-[11px] text-[var(--text-muted)]">
           {snapshot() ? ko.grid.items(snapshot()!.count) : ""}
         </span>
+
+        {/* 종류 필터: 전체 / 사진 / 영상 */}
+        <div class="flex overflow-hidden rounded border border-[var(--border)] text-[11px]">
+          <For each={[["all", ko.filter.all], ["image", ko.filter.image], ["video", ko.filter.video]] as [KindFilter, string][]}>
+            {([k, label]) => (
+              <button
+                class="px-2 py-0.5"
+                classList={{
+                  "bg-[var(--bg-active)] text-[var(--text-primary)]": kindFilter() === k,
+                  "text-[var(--text-muted)] hover:bg-[var(--bg-hover)]": kindFilter() !== k,
+                }}
+                onClick={() => setKindFilter(k)}
+              >
+                {label}
+              </button>
+            )}
+          </For>
+        </div>
+
+        {/* 정렬: 키 선택 + 방향 토글 */}
+        <div class="flex items-center gap-1 text-[11px] text-[var(--text-secondary)]">
+          <select
+            class="rounded border border-[var(--border)] bg-[var(--bg-panel)] px-1.5 py-0.5 outline-none"
+            value={sortKey()}
+            onChange={(e) => setSort(e.currentTarget.value as SortKey, sortDesc())}
+          >
+            <For each={[["taken", ko.sort.taken], ["name", ko.sort.name], ["size", ko.sort.size], ["mtime", ko.sort.mtime]] as [SortKey, string][]}>
+              {([k, label]) => <option value={k}>{label}</option>}
+            </For>
+          </select>
+          <button
+            class="rounded border border-[var(--border)] px-1.5 py-0.5 hover:bg-[var(--bg-hover)]"
+            onClick={() => setSort(sortKey(), !sortDesc())}
+            title={sortDesc() ? ko.sort.desc : ko.sort.asc}
+          >
+            {sortDesc() ? "↓" : "↑"}
+          </button>
+        </div>
+
+        {/* 썸네일 정보 오버레이 토글 */}
+        <button
+          class="rounded border border-[var(--border)] px-1.5 py-0.5 text-[11px]"
+          classList={{
+            "bg-[var(--bg-active)] text-[var(--text-primary)]": showInfo(),
+            "text-[var(--text-muted)] hover:bg-[var(--bg-hover)]": !showInfo(),
+          }}
+          onClick={toggleShowInfo}
+          title={ko.grid.infoToggle}
+        >
+          ⓘ
+        </button>
+
         {/* 그리드 줌 슬라이더 */}
         <div class="ml-auto flex items-center gap-1.5 text-[var(--text-muted)]" title="썸네일 크기 (Ctrl+휠)">
           <span class="text-xs">🔍</span>

src/shell/ShortcutsOverlay.tsx

@@ -0,0 +1,58 @@
+// 키보드 단축키 도움말 오버레이 (? 키로 열기).
+import { For, onCleanup, onMount, Show, type Component } from "solid-js";
+import { ko } from "../i18n/ko";
+import { closeShortcuts, shortcutsOpen } from "../state/store";
+
+export const ShortcutsOverlay: Component = () => {
+  onMount(() => {
+    const onKey = (e: KeyboardEvent) => {
+      if (!shortcutsOpen()) return;
+      if (e.key === "Escape" || e.key === "?") {
+        e.preventDefault();
+        e.stopPropagation();
+        closeShortcuts();
+      }
+    };
+    window.addEventListener("keydown", onKey, { capture: true });
+    onCleanup(() => window.removeEventListener("keydown", onKey, { capture: true }));
+  });
+
+  return (
+    <Show when={shortcutsOpen()}>
+      <div
+        class="fixed inset-0 z-50 grid place-items-center bg-black/50"
+        onClick={closeShortcuts}
+      >
+        <div
+          class="max-h-[80vh] w-[min(30rem,92vw)] overflow-y-auto rounded-lg border border-[var(--border)] bg-[var(--bg-panel)] p-5 shadow-xl"
+          onClick={(e) => e.stopPropagation()}
+        >
+          <div class="mb-3 flex items-center justify-between">
+            <span class="text-sm font-semibold text-[var(--text-primary)]">
+              {ko.shortcuts.title}
+            </span>
+            <button
+              class="rounded px-2 text-[var(--text-secondary)] hover:bg-[var(--bg-hover)]"
+              onClick={closeShortcuts}
+              title={ko.shortcuts.close}
+            >
+              ✕
+            </button>
+          </div>
+          <div class="flex flex-col gap-1.5">
+            <For each={ko.shortcuts.items}>
+              {([keys, desc]) => (
+                <div class="flex items-center justify-between gap-4 text-xs">
+                  <kbd class="shrink-0 rounded border border-[var(--border)] bg-[var(--bg-app)] px-1.5 py-0.5 font-mono text-[11px] text-[var(--text-secondary)]">
+                    {keys}
+                  </kbd>
+                  <span class="text-right text-[var(--text-secondary)]">{desc}</span>
+                </div>
+              )}
+            </For>
+          </div>
+        </div>
+      </div>
+    </Show>
+  );
+};

src/state/store.ts

@@ -15,6 +15,8 @@ import {
   type DedupeProgress,
   type PendingCounts,
   type ScanProgress,
+  type SnapOpts,
+  type SortKey,
 } from "../ipc/commands";
 
 // ── 앱 정보 (미디어 서버 포트/토큰 포함) ─────────────────
@@ -43,6 +45,36 @@ const [snapshot, setSnapshot] = createSignal<Snapshot | undefined>();
 const [loading, setLoading] = createSignal(false);
 export { view, snapshot, loading };
 
+// ── 정렬 / 종류 필터 (툴바) ──────────────────────────────
+const [sortKey, setSortKeySig] = createSignal<SortKey>("taken");
+const [sortDesc, setSortDescSig] = createSignal(true);
+export type KindFilter = "all" | "image" | "video";
+const [kindFilter, setKindFilterSig] = createSignal<KindFilter>("all");
+export { sortKey, sortDesc, kindFilter };
+export type { SortKey };
+
+/** 정렬 변경 → 재조회 */
+export function setSort(key: SortKey, desc: boolean): void {
+  setSortKeySig(key);
+  setSortDescSig(desc);
+  void refreshSnapshot();
+}
+/** 종류 필터 변경(전체/사진/영상) → 재조회 */
+export function setKindFilter(k: KindFilter): void {
+  setKindFilterSig(k);
+  void refreshSnapshot();
+}
+
+// 그리드 썸네일에 파일명·크기 오버레이 표시 (localStorage 유지)
+const INFO_KEY = "archive.grid.infoOverlay";
+const [showInfo, setShowInfoRaw] = createSignal(localStorage.getItem(INFO_KEY) === "1");
+export { showInfo };
+export function toggleShowInfo(): void {
+  const n = !showInfo();
+  setShowInfoRaw(n);
+  localStorage.setItem(INFO_KEY, n ? "1" : "0");
+}
+
 let viewSeq = 0;
 
 export async function setView(v: View): Promise<void> {
@@ -55,26 +87,31 @@ export async function refreshSnapshot(): Promise<void> {
   const v = view();
   const seq = ++viewSeq;
   setLoading(true);
+  const opts: SnapOpts = {
+    sortKey: sortKey(),
+    sortDesc: sortDesc(),
+    kind: kindFilter() === "image" ? 0 : kindFilter() === "video" ? 1 : null,
+  };
   try {
     let snap: Snapshot;
     switch (v.type) {
       case "all":
-        snap = await folderSnapshot({});
+        snap = await folderSnapshot({ ...opts });
         break;
       case "source":
-        snap = await folderSnapshot({ sourceId: v.sourceId });
+        snap = await folderSnapshot({ sourceId: v.sourceId, ...opts });
         break;
       case "folder":
-        snap = await folderSnapshot({ folderId: v.folderId, recursive: v.recursive });
+        snap = await folderSnapshot({ folderId: v.folderId, recursive: v.recursive, ...opts });
         break;
       case "search":
-        snap = await searchSnapshot(v.query);
+        snap = await searchSnapshot(v.query, opts);
         break;
       case "tag":
-        snap = await tagSnapshot(v.tagId);
+        snap = await tagSnapshot(v.tagId, opts);
         break;
       case "smart":
-        snap = await smartSnapshot(v.smartId);
+        snap = await smartSnapshot(v.smartId, opts);
         break;
     }
     if (seq === viewSeq) setSnapshot(snap);
@@ -193,6 +230,12 @@ const [repeatMode, setRepeatMode] = createSignal(false);
 export { repeatMode };
 export const toggleRepeat = () => setRepeatMode((r) => !r);
 
+// ── 단축키 도움말 오버레이 ───────────────────────────────
+const [shortcutsOpen, setShortcutsOpen] = createSignal(false);
+export { shortcutsOpen };
+export const openShortcuts = () => setShortcutsOpen(true);
+export const closeShortcuts = () => setShortcutsOpen(false);
+
 // ── 중복 검토 패널 ───────────────────────────────────────
 const [dedupeOpen, setDedupeOpen] = createSignal(false);
 export { dedupeOpen };