feat: add storage info, UI threshold control, and FLAC/OGG duration

- Show total audio storage used and disk free/total in the page header
- Add per-page threshold input (seeded from server --threshold) so the
  loudness threshold can be adjusted without restarting the server;
  each Analyse request sends the current UI value to the backend
- Fix empty Duration column: FLAC, OGG, and Opus files now report
  duration via soundfile header metadata (no full decode required)
- New /api/storage and /api/config endpoints support the above features

web.py

@@ -17,6 +17,7 @@ import json
 import math
 import os
 import re
+import shutil
 import struct
 import wave
 from datetime import datetime
@@ -68,6 +69,21 @@ def _get_wav_info(path: Path):
         return None, None, None
 
 
+def _get_audio_duration(path: Path):
+    """Return duration in seconds for any supported audio file, or None."""
+    ext = path.suffix.lower()
+    if ext == '.wav':
+        dur, _, _ = _get_wav_info(path)
+        return dur
+    if SOUNDFILE_AVAILABLE and ext in ('.flac', '.ogg', '.opus'):
+        try:
+            with sf.SoundFile(path) as f:
+                return round(len(f) / f.samplerate, 2)
+        except Exception:
+            return None
+    return None
+
+
 def _compute_rms_windows_wav(wf, channels: int, sampwidth: int, framerate: int,
                               window_samples: int):
     """Yield rms_0_to_1 for every window in the open wave file."""
@@ -209,9 +225,7 @@ def list_files(recordings_dir: str):
         stat = path.stat()
         rel  = str(path.relative_to(base)).replace('\\', '/')
 
-        duration = None
+        duration = _get_audio_duration(path)
-        if path.suffix.lower() == '.wav':
-            duration, _, _ = _get_wav_info(path)
 
         files.append({
             'name':      rel,
@@ -248,6 +262,10 @@ class _Handler(BaseHTTPRequestHandler):
             self._api_analyze(qs)
         elif p == '/api/status':
             self._api_status()
+        elif p == '/api/storage':
+            self._api_storage()
+        elif p == '/api/config':
+            self._api_config()
         elif p.startswith('/download/'):
             self._download(unquote(p[len('/download/'):]))
         elif p.startswith('/stream/'):
@@ -272,6 +290,12 @@ class _Handler(BaseHTTPRequestHandler):
         if path is None:
             return
 
+        try:
+            threshold = float(qs.get('threshold', [self.threshold])[0])
+            threshold = max(0.0, min(1.0, threshold))
+        except (ValueError, TypeError):
+            threshold = self.threshold
+
         status_path = Path(self.recordings_dir) / 'status.json'
         try:
             with open(status_path) as fh:
@@ -283,12 +307,12 @@ class _Handler(BaseHTTPRequestHandler):
 
         ext = path.suffix.lower()
         if ext == '.wav':
-            result = analyze_wav(path, threshold=self.threshold)
+            result = analyze_wav(path, threshold=threshold)
         elif ext == '.flac':
             if not (NUMPY_AVAILABLE and SOUNDFILE_AVAILABLE):
                 self._json_err(400, 'FLAC analysis requires: pip install numpy soundfile')
                 return
-            result = analyze_flac(path, threshold=self.threshold)
+            result = analyze_flac(path, threshold=threshold)
         else:
             self._json_err(400, f'Loudness analysis is not available for {ext} files')
             return
@@ -374,6 +398,27 @@ class _Handler(BaseHTTPRequestHandler):
                         break
                     self.wfile.write(chunk)
 
+    def _api_storage(self):
+        base = Path(self.recordings_dir)
+        used = 0
+        if base.exists():
+            used = sum(
+                p.stat().st_size
+                for p in base.rglob('*')
+                if p.is_file() and p.suffix.lower() in AUDIO_EXTENSIONS
+            )
+        try:
+            du = shutil.disk_usage(str(base) if base.exists() else '.')
+            disk_free, disk_total = du.free, du.total
+        except Exception:
+            disk_free = disk_total = None
+        data = json.dumps({'used': used, 'disk_free': disk_free, 'disk_total': disk_total})
+        self._send(200, data.encode(), 'application/json')
+
+    def _api_config(self):
+        data = json.dumps({'threshold': self.threshold})
+        self._send(200, data.encode(), 'application/json')
+
     def _safe_path(self, filename: str):
         base = Path(self.recordings_dir).resolve()
         try:
@@ -425,10 +470,18 @@ body{background:var(--bg);color:var(--txt);font:14px/1.5 system-ui,sans-serif}
 /* sr-only */
 .sr{position:absolute;width:1px;height:1px;padding:0;margin:-1px;
   overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
-header{padding:20px 28px;border-bottom:1px solid var(--brd);
+header{padding:16px 28px;border-bottom:1px solid var(--brd);
-  display:flex;align-items:baseline;gap:12px;flex-wrap:wrap}
+  display:flex;align-items:center;gap:12px;flex-wrap:wrap}
 header h1{font-size:18px;font-weight:600}
-#subtitle{color:var(--muted);font-size:13px;margin-right:auto}
+#subtitle{color:var(--muted);font-size:13px}
+#storage-info{color:var(--muted);font-size:12px;margin-right:auto}
+.controls-bar{display:flex;align-items:center;gap:10px;padding:10px 28px;
+  border-bottom:1px solid var(--brd);background:var(--surf);flex-wrap:wrap}
+.controls-bar label{font-size:13px;color:var(--muted);white-space:nowrap}
+.controls-bar input[type=number]{width:70px;background:var(--bg);border:1px solid var(--brd);
+  color:var(--txt);padding:3px 6px;border-radius:4px;font-size:13px}
+.controls-bar input[type=number]:focus{outline:2px solid var(--accent);outline-offset:1px}
+.controls-hint{font-size:11px;color:var(--muted)}
 .wrap{padding:20px 28px}
 table{width:100%;border-collapse:collapse}
 th{text-align:left;padding:9px 10px;color:var(--muted);font-weight:500;font-size:12px;
@@ -479,8 +532,15 @@ audio{width:100%;height:36px;border-radius:4px;display:block;
 <header>
   <h1>ISR Archive</h1>
   <span id="subtitle" aria-live="polite" aria-atomic="true">Loading…</span>
+  <span id="storage-info" aria-live="polite"></span>
   <button id="refresh-btn" aria-label="Refresh file list">&#8635; Refresh</button>
 </header>
+<div class="controls-bar">
+  <label for="threshold-input">Analysis threshold:</label>
+  <input type="number" id="threshold-input" min="0" max="1" step="0.005" value="0.05"
+    aria-describedby="threshold-hint">
+  <span id="threshold-hint" class="controls-hint">RMS 0–1 · sections above this value are marked loud</span>
+</div>
 <div class="wrap" id="main">
   <table aria-label="Recordings archive">
     <thead>
@@ -588,8 +648,10 @@ async function analyse(filename, cell, btn) {
   btn.disabled = true;
   btn.textContent = '…';
   cell.innerHTML = '<div class="spin" aria-live="polite" aria-busy="true">Analysing…</div>';
+  const threshold = document.getElementById('threshold-input').value || '0.05';
   try {
-    const r = await fetch('/api/analyze?file='+encodeURIComponent(filename));
+    const r = await fetch('/api/analyze?file='+encodeURIComponent(filename)
+      +'&threshold='+encodeURIComponent(threshold));
     const d = await r.json();
     if (d.error) {
       cell.innerHTML = `<div class="spin" role="alert">Error: ${esc(d.error)}</div>`;
@@ -624,6 +686,17 @@ async function analyse(filename, cell, btn) {
   }
 }
 
+async function updateStorage() {
+  try {
+    const s = await (await fetch('/api/storage')).json();
+    const el = document.getElementById('storage-info');
+    let txt = fmtSize(s.used) + ' used';
+    if (s.disk_free != null) txt += ' · ' + fmtSize(s.disk_free) + ' free';
+    if (s.disk_total != null) txt += ' of ' + fmtSize(s.disk_total);
+    el.textContent = txt;
+  } catch(e) {}
+}
+
 async function load() {
   const refreshBtn = document.getElementById('refresh-btn');
   refreshBtn.disabled = true;
@@ -646,6 +719,7 @@ async function load() {
   document.getElementById('subtitle').textContent =
     `${n} recording${n!==1?'s':''} found`;
   document.getElementById('empty').style.display = n ? 'none' : '';
+  updateStorage();
   if (!n) { refreshBtn.disabled = false; return; }
 
   files.forEach((f, i) => {
@@ -736,7 +810,12 @@ async function pollStatus() {
 }
 
 document.getElementById('refresh-btn').addEventListener('click', load);
-load().then(() => setInterval(pollStatus, 5000));
+
+// Seed threshold input from server config, then start
+fetch('/api/config').then(r => r.json()).then(cfg => {
+  if (cfg.threshold != null)
+    document.getElementById('threshold-input').value = cfg.threshold;
+}).catch(() => {}).finally(() => load().then(() => setInterval(pollStatus, 5000)));
 </script>
 </body>
 </html>"""