feat: hybrid cache-busting for thumbnails and covers

- Add Cache-Control: no-cache headers to thumbnail and cover endpoints
  (GET /api/media/{id}/thumbnail, GET /api/sets/{id}/cover,
   GET /s/{token}/thumbnail) so browsers revalidate instead of
   serving stale cached images after regeneration.

- Add frontend cache-busting via ?t=Date.now() after folder cover
  regeneration so the browser fetches the newly overwritten image.

- Replace toolbar filters with inline search syntax (min:, max:,
  tag:, like:, type:, sort:, minsize:, maxsize:) for faster filtering.

- Remove dedicated toolbar and advanced filter panel; consolidate
  all filtering into the search bar.

- Expand filter state to support filesize_min/filesize_max.

9 files changed, 137 insertions, 79 deletions

diff --git a/internal/api/handlers_file.go b/internal/api/handlers_file.go
index 7e04de7..d8bb14f 100644
--- a/internal/api/handlers_file.go
+++ b/internal/api/handlers_file.go
@@ -80,6 +80,7 @@ func (s *Server) handleThumbnail(w http.ResponseWriter, r *http.Request) {
 	if !requireService(w, s.mediaSvc) {
 		return
 	}
+	w.Header().Set("Cache-Control", "no-cache")
 	s.fileHandler(s.mediaSvc.GetThumbnail)(w, r)
 }
 
diff --git a/internal/api/handlers_media.go b/internal/api/handlers_media.go
index 3863ab0..afb9685 100644
--- a/internal/api/handlers_media.go
+++ b/internal/api/handlers_media.go
@@ -53,6 +53,7 @@ func (s *Server) handleGetSetCover(w http.ResponseWriter, r *http.Request) {
 		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": err.Error()})
 		return
 	}
+	w.Header().Set("Cache-Control", "no-cache")
 	http.ServeFile(w, r, fr.Path)
 }
 
@@ -231,16 +232,19 @@ func (s *Server) handleListMedia(w http.ResponseWriter, r *http.Request) {
 	setIDs := q.Get("set_ids")
 	search := q.Get("search")
 	typ := q.Get("type")
+	fav := q.Get("favorites")
+	minDur := q.Get("min_duration")
+	maxDur := q.Get("max_duration")
 	start := time.Now()
 	filter := parseMediaListQuery(q)
 	media, err := s.mediaSvc.ListMedia(r.Context(), userIDFromContext(r), filter)
 	dur := time.Since(start)
 	if err != nil {
-		fmt.Printf("[api] %s set_id=%s set_ids=%s search=%q type=%s error=%v (took %s)\n", path, setID, setIDs, search, typ, err, dur)
+		fmt.Printf("[api] %s set_id=%s set_ids=%s search=%q type=%s fav=%s min=%s max=%s error=%v (took %s)\n", path, setID, setIDs, search, typ, fav, minDur, maxDur, err, dur)
 		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": err.Error()})
 		return
 	}
-	fmt.Printf("[api] %s set_id=%s set_ids=%s search=%q type=%s returned=%d (took %s)\n", path, setID, setIDs, search, typ, len(media), dur)
+	fmt.Printf("[api] %s set_id=%s set_ids=%s search=%q type=%s fav=%s min=%s max=%s returned=%d (took %s)\n", path, setID, setIDs, search, typ, fav, minDur, maxDur, len(media), dur)
 	writeJSON(w, http.StatusOK, media)
 }
 
diff --git a/internal/api/handlers_share.go b/internal/api/handlers_share.go
index 71b5934..1d8d242 100644
--- a/internal/api/handlers_share.go
+++ b/internal/api/handlers_share.go
@@ -136,6 +136,7 @@ func (s *Server) handleShareThumbnail(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, "not found", http.StatusNotFound)
 		return
 	}
+	w.Header().Set("Cache-Control", "no-cache")
 	s.serveFileResult(w, r, fr, false)
 }
 
diff --git a/internal/repository/media.go b/internal/repository/media.go
index 1fdb365..f47ad7f 100644
--- a/internal/repository/media.go
+++ b/internal/repository/media.go
@@ -197,6 +197,7 @@ func (s *SQLite) ListMedia(ctx context.Context, filter MediaFilter) ([]model.Med
 	if len(filter.Tags) > 0 {
 		query += ` GROUP BY media.id HAVING COUNT(DISTINCT t.name) = ` + fmt.Sprintf("%d", len(filter.Tags))
 	}
+	fmt.Printf("[repo] query=%s args=%v\n", query, args)
 
 	switch filter.Sort {
 	case "duration":
diff --git a/web/index.html b/web/index.html
index df695c2..586c9fa 100644
--- a/web/index.html
+++ b/web/index.html
@@ -36,30 +36,13 @@
 <!-- Main page area -->
 <div class="page" role="main">
   <div class="main-content">
-    <!-- Toolbar: hidden by default, shown on 't' key or when searching -->
-    <div id="toolbar" class="toolbar hidden">
-      <select id="filter-type" aria-label="Filter by type">
-        <option value="">All</option>
-        <option value="video">Video</option>
-        <option value="audio">Audio</option>
-      </select>
-      <button id="filter-favorites" class="btn btn-ghost btn-sm">♥ Favorites</button>
-      <div class="spacer"></div>
-      <button id="filter-toggle" class="btn btn-ghost btn-sm" title="More filters">Filters ▾</button>
-      <span id="result-count" class="text-muted text-xs"></span>
-    </div>
-    <div id="filter-advanced" class="toolbar hidden">
-      <input id="filter-tags" type="text" placeholder="Tags (comma)" aria-label="Filter by tags" class="input-sm">
-      <input id="filter-min-duration" type="number" min="0" placeholder="Min min" aria-label="Min duration minutes" class="input-sm">
-      <input id="filter-max-duration" type="number" min="0" placeholder="Max min" aria-label="Max duration minutes" class="input-sm">
-    </div>
-
-    <!-- Search bar: hidden by default, shown on '/' key -->
+    <!-- Search bar: shown on '/' key -->
     <div id="search-bar" class="search-bar hidden" role="search">
       <span aria-hidden="true">🔎</span>
-      <input id="search-input" type="search" placeholder="Search… (press /)" autocomplete="off" aria-label="Search media">
+      <input id="search-input" type="search" placeholder="Search or filter… (press /)" autocomplete="off" aria-label="Search media">
       <button id="search-clear" class="icon-btn btn-sm" title="Clear">✕</button>
     </div>
+    <div id="result-count" class="text-muted text-xs mt-1"></div>
 
     <!-- Empty state hint: shown when no set is selected -->
     <div id="empty-hint" class="empty-hint">
@@ -146,6 +129,9 @@
         <div class="help-row"><span><kbd>L</kbd></span><span>My Shares</span></div>
         <div class="help-row"><span><kbd>?</kbd></span><span>Show / hide help</span></div>
       </div>
+      <div class="help-search text-muted text-xs mt-2">
+        Search: plain text searches file name. Syntax: <code>min:30</code> <code>max:55</code> <code>tag:a,b</code> <code>like:1</code> <code>type:video</code> <code>sort:random</code> <code>minsize:10</code> <code>maxsize:500</code>
+      </div>
       <div class="help-shares text-muted text-xs mt-2">My Shares: <kbd>↑</kbd> / <kbd>↓</kbd> or <kbd>k</kbd> / <kbd>j</kbd> navigate, <kbd>Enter</kbd> copies, <kbd>Delete</kbd> revokes, <kbd>Esc</kbd> closes.</div>
     </div>
   </div>
diff --git a/web/js/app.js b/web/js/app.js
index 307190f..76436bb 100644
--- a/web/js/app.js
+++ b/web/js/app.js
@@ -2,7 +2,7 @@ import { API } from './api.js';
 import { initKeyboard } from './keyboard.js';
 import { initSelection, clearSelection, select, selectByElement, next, prev, currentIndex, currentElement, navUp, navDown, navLeft, navRight } from './selection.js';
 import { initPlayer, togglePlay, toggleFullscreen, toggleMinimize, toggleDetach, exitFullscreenIfNeeded, currentMediaId, currentMediaInfo, hasLoadedMedia, isPlaybackActive, seekRelative, selectAndPlay } from './player.js';
-import { initSearch, focusSearch, trigger as triggerSearch } from './search.js';
+import { initSearch, focusSearch, trigger as triggerSearch, parseQuery } from './search.js';
 import { initShuffle, toggle as toggleShuffle, isOn as isShuffle } from './shuffle.js';
 import { initThemes } from './themes.js';
 import { initNotes, open as openNotes } from './notes.js';
@@ -76,8 +76,10 @@ async function initApp() {
   initSelection();
   initSearch({
     onChange: (q) => {
-      state.filters.search = q;
+      const parsed = parseQuery(q);
+      Object.assign(state.filters, parsed);
       state.folderPath = '';
+      console.log('[search] raw:', q, 'parsed:', parsed, 'filters:', state.filters);
       loadMedia();
     },
     input: document.getElementById('search-input'),
@@ -126,7 +128,6 @@ async function initApp() {
     toggleDetach: () => toggleDetach(),
     download: downloadSelected,
     help: toggleHelp,
-    toolbar: toggleToolbar,
     backspace: () => { navigateBack(); },
     sidebar: toggleSidebar,
     upload: () => showUpload(),
@@ -136,8 +137,6 @@ async function initApp() {
     sharesNavDown: () => sharesNav(1),
     sharesCopy: copySelectedShare,
     sharesDelete: deleteSelectedShare,
-    focusMinDuration: () => focusFilter('filter-min-duration'),
-    focusMaxDuration: () => focusFilter('filter-max-duration'),
   });
   initNotes(() => toast('Note saved'));
   initAdmin();
@@ -147,21 +146,6 @@ async function initApp() {
   initShares();
   initMediaInfo();
 
-  // Filters
-  document.getElementById('filter-type')?.addEventListener('change', (e) => { state.filters.type = e.target.value; state.folderPath = ''; loadMedia(); });
-  document.getElementById('filter-favorites')?.addEventListener('click', (e) => {
-    state.filters.favorites = !state.filters.favorites;
-    e.target.classList.toggle('active', state.filters.favorites);
-    state.folderPath = '';
-    loadMedia();
-  });
-  document.getElementById('filter-tags')?.addEventListener('change', (e) => { state.filters.tags = e.target.value; state.folderPath = ''; loadMedia(); });
-  document.getElementById('filter-min-duration')?.addEventListener('change', (e) => { state.filters.minDuration = e.target.value; state.folderPath = ''; loadMedia(); });
-  document.getElementById('filter-max-duration')?.addEventListener('change', (e) => { state.filters.maxDuration = e.target.value; state.folderPath = ''; loadMedia(); });
-  document.getElementById('filter-toggle')?.addEventListener('click', () => {
-    document.getElementById('filter-advanced')?.classList.toggle('hidden');
-  });
-
   // Sidebar close
   document.getElementById('menu-close')?.addEventListener('click', () => {
     document.getElementById('sidebar')?.classList.remove('open');
@@ -304,7 +288,7 @@ async function loadMedia() {
 
     // When viewing a single set with no filters/search, use the browse endpoint
     // so that subfolders are presented as folders to navigate into.
-    if (singleSetId && !setIds && !isShuffle() && !state.filters.search && !state.filters.type && !state.filters.favorites && !state.filters.tags && !state.filters.minDuration && !state.filters.maxDuration) {
+    if (singleSetId && !setIds && !isShuffle() && !hasActiveFilters()) {
       const data = await API.browse(singleSetId, state.folderPath);
       updateBreadcrumb(data.current_path);
       setMedia(mediaWithBrowsePath(data.media || [], data.current_path || ''));
@@ -313,6 +297,7 @@ async function loadMedia() {
       resultCount.textContent = `${total} items`;
     } else {
       breadcrumb?.classList.add('hidden');
+      const sort = isShuffle() ? 'random' : (state.filters.sort || 'name');
       const params = {
         set_id: setIds ? '' : String(singleSetId || state.selectedSetId || ''),
         set_ids: setIds,
@@ -322,7 +307,9 @@ async function loadMedia() {
         tags: state.filters.tags || '',
         min_duration: state.filters.minDuration ? String(parseFloat(state.filters.minDuration) * 60) : '',
         max_duration: state.filters.maxDuration ? String(parseFloat(state.filters.maxDuration) * 60) : '',
-        sort: isShuffle() ? 'random' : 'name',
+        filesize_min: state.filters.minFileSize ? String(parseInt(state.filters.minFileSize, 10) * 1024 * 1024) : '',
+        filesize_max: state.filters.maxFileSize ? String(parseInt(state.filters.maxFileSize, 10) * 1024 * 1024) : '',
+        sort,
         limit: '1000',
       };
       const data = await API.media(params);
@@ -404,7 +391,18 @@ function renderBrowse(data) {
       if (!setId) return;
       const name = b.closest('.folder-card')?.dataset.name;
       const folder = state.folderPath ? `${state.folderPath}/${name}` : name;
-      try { await API.regenCover(setId, folder); toast('Folder cover regenerated'); loadMedia(); }
+      try {
+        await API.regenCover(setId, folder);
+        toast('Folder cover regenerated');
+        await loadMedia();
+        // Force refresh the folder cover image to bypass browser cache
+        const folderCard = document.querySelector(`.folder-card[data-name="${CSS.escape(name)}"]`);
+        const img = folderCard?.querySelector('img');
+        if (img) {
+          const base = img.src.split('?')[0];
+          img.src = `${base}?t=${Date.now()}`;
+        }
+      }
       catch (err) { toast(err.message || 'Cover failed', 'error'); }
     });
   });
@@ -575,7 +573,17 @@ function canTraverseBrowseFolders() {
 }
 
 function hasActiveFilters() {
-  return !!(state.filters.search || state.filters.type || state.filters.favorites || state.filters.tags || state.filters.minDuration || state.filters.maxDuration);
+  return !!(
+    state.filters.search ||
+    state.filters.type ||
+    state.filters.favorites ||
+    state.filters.tags ||
+    state.filters.minDuration ||
+    state.filters.maxDuration ||
+    state.filters.minFileSize ||
+    state.filters.maxFileSize ||
+    state.filters.sort
+  );
 }
 
 async function findCrossFolderPlayable(delta, preferCurrent) {
@@ -982,28 +990,6 @@ function toggleHelp() {
   modal.classList.toggle('open');
 }
 
-// Toolbar / sidebar / search visibility toggles
-function toggleToolbar() {
-  const toolbar = document.getElementById('toolbar');
-  toolbar?.classList.toggle('hidden');
-}
-
-function toggleSidebar() {
-  const sidebar = document.getElementById('sidebar');
-  const page = document.querySelector('.page');
-  if (!sidebar) return;
-  const open = sidebar.classList.toggle('open');
-  page?.classList.toggle('has-sidebar', open);
-}
-
-function focusFilter(id) {
-  const el = document.getElementById(id);
-  if (!el) return;
-  document.getElementById('filter-advanced')?.classList.remove('hidden');
-  el.focus();
-  el.select();
-}
-
 function showSearch() {
   const bar = document.getElementById('search-bar');
   bar?.classList.remove('hidden');
diff --git a/web/js/keyboard.js b/web/js/keyboard.js
index 3a1ee25..a9ebf2a 100644
--- a/web/js/keyboard.js
+++ b/web/js/keyboard.js
@@ -160,7 +160,6 @@ export function initKeyboard(handlers) {
         handlers.search?.(e);
         break;
       case 'i': handlers.mediaInfo?.(e); break;
-      case 't': handlers.toolbar?.(e); break;
       case 'd': handlers.toggleDetach?.(e); break;
       case 'D': handlers.download?.(e); break;
       case 'u': handlers.upload?.(e); break;
@@ -169,14 +168,6 @@ export function initKeyboard(handlers) {
         e.preventDefault();
         handlers.help?.(e);
         break;
-      case ',':
-        e.preventDefault();
-        handlers.focusMinDuration?.(e);
-        break;
-      case '.':
-        e.preventDefault();
-        handlers.focusMaxDuration?.(e);
-        break;
     }
   });
 }
diff --git a/web/js/search.js b/web/js/search.js
index dfb698a..b337027 100644
--- a/web/js/search.js
+++ b/web/js/search.js
@@ -26,10 +26,88 @@ export function initSearch({ onChange, input, clearBtn }) {
 
 export function focusSearch() {
   const input = document.getElementById('search-input');
-  if (input) input.focus();
+  if (input) {
+    input.focus();
+    input.select();
+  }
 }
 
 export function trigger(query) {
   clearTimeout(_debounceTimer);
   _onChange(query);
 }
+
+/**
+ * Parse a raw search string into structured filters and free-text search.
+ *
+ * Supported syntax:
+ *   min:30        – minimum duration in minutes
+ *   max:55        – maximum duration in minutes
+ *   tag:a,b       – comma-separated tag names
+ *   like:1        – only favorited items
+ *   type:video    – media type (video | audio)
+ *   sort:name     – sort order (name | date | duration | play_count | random)
+ *   minsize:10    – minimum file size in MB
+ *   maxsize:500   – maximum file size in MB
+ *
+ * Anything that does not match key:value becomes free-text search.
+ */
+export function parseQuery(raw) {
+  const filters = {
+    type: '',
+    favorites: false,
+    tags: '',
+    sort: '',
+    minDuration: '',
+    maxDuration: '',
+    minFileSize: '',
+    maxFileSize: '',
+    search: '',
+  };
+  const tokens = [];
+  // Split by whitespace while respecting double-quoted strings.
+  const parts = raw.match(/(".*?"|\S+)/g) || [];
+  for (const part of parts) {
+    const m = part.match(/^([a-zA-Z_]+):(.+)$/);
+    if (m) {
+      const key = m[1].toLowerCase();
+      let value = m[2];
+      if (value.startsWith('"') && value.endsWith('"')) {
+        value = value.slice(1, -1);
+      }
+      switch (key) {
+        case 'min':
+          filters.minDuration = value;
+          break;
+        case 'max':
+          filters.maxDuration = value;
+          break;
+        case 'tag':
+          filters.tags = value;
+          break;
+        case 'like':
+          filters.favorites = ['1', 'true', 'yes'].includes(value);
+          break;
+        case 'type':
+          filters.type = value;
+          break;
+        case 'sort':
+          filters.sort = value;
+          break;
+        case 'minsize':
+          filters.minFileSize = value;
+          break;
+        case 'maxsize':
+          filters.maxFileSize = value;
+          break;
+        default:
+          tokens.push(part);
+          break;
+      }
+    } else {
+      tokens.push(part);
+    }
+  }
+  filters.search = tokens.join(' ').trim();
+  return filters;
+}
diff --git a/web/js/state.js b/web/js/state.js
index 4d580b9..f0879c1 100644
--- a/web/js/state.js
+++ b/web/js/state.js
@@ -4,7 +4,17 @@ export const state = {
   selectedSetId: null,
   selectedSetIds: [], // multi-selection
   media: [],
-  filters: { type: '', search: '', favorites: false, tags: '', sort: 'name', minDuration: '', maxDuration: '' },
+  filters: {
+    type: '',
+    search: '',
+    favorites: false,
+    tags: '',
+    sort: '',
+    minDuration: '',
+    maxDuration: '',
+    minFileSize: '',
+    maxFileSize: '',
+  },
   isAdmin: false,
   folderPath: '',   // current subfolder path within the selected set
   sharesCurrentRow: -1,