feat: dashboard UI with real-time stats, light/dark mode, session metrics

Dockerfile

@@ -9,6 +9,8 @@ RUN pip install --no-cache-dir -r requirements.txt
 
 COPY . .
 
+EXPOSE 8081 8082
+
 HEALTHCHECK --interval=60s --timeout=10s --start-period=5s --retries=3 \
     CMD python -c "import urllib.request; urllib.request.urlopen('http://localhost:8081/health')" || exit 1
 

dashboard.py

@@ -0,0 +1,146 @@
+import json
+import os
+import threading
+from http.server import HTTPServer, BaseHTTPRequestHandler
+
+from health import HealthServer, SyncSession
+
+
+class DashboardServer:
+    def __init__(self, port: int = 8082, health: HealthServer = None, session: SyncSession = None):
+        self.port = port
+        self.health = health
+        self.session = session
+        self.server = None
+        self.thread = None
+        self._lock = threading.Lock()
+        self._syncing = False
+        self._next_sync_in = 0
+        self._event_count = 0
+        self._backoff_min = 0
+        self._config = {}
+        self._base_dir = os.path.dirname(os.path.abspath(__file__))
+
+    def start(self):
+        handler = self._make_handler()
+        self.server = HTTPServer(("0.0.0.0", self.port), handler)
+        self.thread = threading.Thread(target=self.server.serve_forever, daemon=True)
+        self.thread.start()
+
+    def stop(self):
+        if self.server:
+            self.server.shutdown()
+            self.server = None
+            self.thread = None
+
+    def update_config(self, config_dict: dict):
+        with self._lock:
+            self._config = dict(config_dict)
+
+    def set_syncing(self, syncing: bool):
+        with self._lock:
+            self._syncing = syncing
+
+    def set_next_sync_in(self, seconds: int):
+        with self._lock:
+            self._next_sync_in = seconds
+
+    def set_event_count(self, n: int):
+        with self._lock:
+            self._event_count = n
+
+    def set_backoff_min(self, n: int):
+        with self._lock:
+            self._backoff_min = n
+
+    def _get_status(self):
+        with self._lock:
+            syncing = self._syncing
+            next_sync_in = self._next_sync_in
+            event_count = self._event_count
+            backoff_min = self._backoff_min
+            config = dict(self._config)
+
+        last_sync = None
+        duration = 0.0
+        last_success = None
+        if self.health:
+            with self.health.lock:
+                last_sync = self.health.last_sync
+                duration = self.health.last_sync_duration
+                last_success = self.health.last_sync_success
+
+        status = "idle"
+        if syncing:
+            status = "syncing"
+        elif last_success is False:
+            status = "error"
+        elif backoff_min > 0:
+            status = "backoff"
+
+        session_data = {}
+        history = []
+        if self.session:
+            session_data = self.session.get_status()
+            history = session_data.get("history", [])
+
+        ics_latency = 0.0
+        if self.session and self.session.non_skip_count > 0:
+            ics_latency = round(self.session.total_latency_ms / self.session.non_skip_count)
+
+        return {
+            "status": status,
+            "last_sync": last_sync.isoformat() if last_sync else None,
+            "duration": duration,
+            "ics_latency_ms": ics_latency,
+            "event_count": event_count,
+            "next_sync_in": next_sync_in,
+            "session": session_data,
+            "history": history,
+            "config": config,
+        }
+
+    def _make_handler(self):
+        server_self = self
+        base_dir = server_self._base_dir
+
+        class Handler(BaseHTTPRequestHandler):
+            def do_GET(self):
+                if self.path == "/api/status":
+                    self._handle_api(server_self)
+                elif self.path == "/":
+                    self._handle_dashboard(base_dir)
+                else:
+                    self.send_response(404)
+                    self.send_header("Content-Type", "application/json")
+                    self.end_headers()
+                    self.wfile.write(json.dumps({"error": "not found"}).encode())
+
+            def _handle_api(self, srv):
+                data = srv._get_status()
+                body = json.dumps(data).encode()
+                self.send_response(200)
+                self.send_header("Content-Type", "application/json")
+                self.end_headers()
+                self.wfile.write(body)
+
+            def _handle_dashboard(self, base):
+                html_path = os.path.join(base, "static", "dashboard.html")
+                try:
+                    with open(html_path, "r", encoding="utf-8") as f:
+                        content = f.read()
+                    body = content.encode("utf-8")
+                    self.send_response(200)
+                    self.send_header("Content-Type", "text/html; charset=utf-8")
+                    self.end_headers()
+                    self.wfile.write(body)
+                except FileNotFoundError:
+                    self.send_response(404)
+                    self.send_header("Content-Type", "application/json")
+                    self.end_headers()
+                    self.wfile.write(json.dumps({"error": "dashboard not found"}).encode())
+
+            def log_message(self, format, *args):
+                pass
+
+        return Handler

docker-compose.yml

@@ -3,6 +3,9 @@ services:
     image: lagortinez/baikal-sync:latest
     container_name: baikal-sync
     restart: always
+    ports:
+      - "8081:8081"
+      - "8082:8082"
     environment:
       - ICS_URL=${ICS_URL}
       - BAIKAL_URL=${BAIKAL_URL}

health.py

@@ -1,10 +1,83 @@
 import json
 import threading
+import time
+from collections import deque
 from datetime import datetime, timezone
 from http.server import HTTPServer, BaseHTTPRequestHandler
 from io import StringIO
 
 
+class SyncSession:
+    def __init__(self):
+        self._lock = threading.Lock()
+        self.start_time = time.time()
+        self.syncs_total = 0
+        self.syncs_failed = 0
+        self.syncs_skipped = 0
+        self.total_added = 0
+        self.total_updated = 0
+        self.total_deleted = 0
+        self.total_duration = 0.0
+        self.total_latency_ms = 0.0
+        self.non_skip_count = 0
+        self.bandwidth_bytes = 0
+        self.bandwidth_saved_bytes = 0
+        self.history = deque(maxlen=50)
+
+    def record(self, ok: bool, duration: float, added: int, updated: int, deleted: int, skipped: bool, ics_latency_ms: float, msg: str, ics_download_size: int = 0) -> None:
+        with self._lock:
+            self.syncs_total += 1
+            ts = time.strftime("%H:%M:%S", time.gmtime())
+            if not ok:
+                self.syncs_failed += 1
+            if skipped:
+                self.syncs_skipped += 1
+            self.total_added += added
+            self.total_updated += updated
+            self.total_deleted += deleted
+            if not skipped:
+                self.non_skip_count += 1
+            self.total_duration += duration
+            self.total_latency_ms += ics_latency_ms
+            if ics_download_size:
+                self.bandwidth_bytes += ics_download_size
+            self.history.append({
+                "time": ts,
+                "ok": ok,
+                "duration": round(duration, 2),
+                "added": added,
+                "updated": updated,
+                "deleted": deleted,
+                "skipped": skipped,
+                "latency_ms": round(ics_latency_ms),
+                "msg": msg,
+            })
+
+    def get_status(self) -> dict:
+        with self._lock:
+            uptime = time.time() - self.start_time
+            avg_dur = round(self.total_duration / self.non_skip_count, 2) if self.non_skip_count > 0 else 0
+            avg_lat = round(self.total_latency_ms / self.non_skip_count) if self.non_skip_count > 0 else 0
+            return {
+                "uptime_sec": round(uptime),
+                "syncs_total": self.syncs_total,
+                "syncs_failed": self.syncs_failed,
+                "syncs_skipped": self.syncs_skipped,
+                "total_added": self.total_added,
+                "total_updated": self.total_updated,
+                "total_deleted": self.total_deleted,
+                "avg_duration": avg_dur,
+                "avg_latency_ms": avg_lat,
+                "bandwidth_bytes": self.bandwidth_bytes,
+                "bandwidth_saved_bytes": self.bandwidth_saved_bytes,
+                "history": list(self.history),
+            }
+
+    def add_saved_bandwidth(self, bytes_saved: int) -> None:
+        with self._lock:
+            self.bandwidth_saved_bytes += bytes_saved
+
+
 class HealthServer:
     def __init__(self, port: int = 8081):
         self.port = port

static/dashboard.html

@@ -0,0 +1,731 @@
+<!DOCTYPE html>
+<html lang="en" data-theme="dark">
+<head>
+<meta charset="UTF-8">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
+<title>Baikal Sync Dashboard</title>
+<style>
+*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
+
+:root {
+  --transition: 0.3s ease;
+  --green: #00b894;
+  --blue: #74b9ff;
+  --yellow: #fdcb6e;
+  --red: #e17055;
+  --purple: #a29bfe;
+}
+
+[data-theme="dark"] {
+  --bg: #0f1117;
+  --card: #1a1d27;
+  --border: #2e3345;
+  --text: #e4e6f0;
+  --text-secondary: #8b90a0;
+  --shadow: 0 2px 12px rgba(0,0,0,0.3);
+  --chart-bg: #12141c;
+}
+
+[data-theme="light"] {
+  --bg: #f5f7fa;
+  --card: #ffffff;
+  --border: #e2e8f0;
+  --text: #1a1d27;
+  --text-secondary: #64748b;
+  --shadow: 0 2px 12px rgba(0,0,0,0.08);
+  --chart-bg: #f0f3f8;
+}
+
+body {
+  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, sans-serif;
+  background: var(--bg);
+  color: var(--text);
+  line-height: 1.6;
+  transition: background var(--transition), color var(--transition);
+  min-height: 100vh;
+}
+
+.container { max-width: 1200px; margin: 0 auto; padding: 24px 16px; }
+
+header {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  margin-bottom: 28px;
+}
+
+.logo { display: flex; align-items: center; gap: 10px; font-size: 1.5rem; font-weight: 700; }
+
+.status-dot {
+  width: 12px; height: 12px; border-radius: 50%; background: var(--green);
+  animation: pulse 2s ease-in-out infinite;
+}
+
+.status-dot.error { background: var(--red); }
+.status-dot.syncing { background: var(--blue); animation-duration: 0.6s; }
+.status-dot.backoff { background: var(--yellow); }
+
+@keyframes pulse {
+  0%, 100% { box-shadow: 0 0 0 0 rgba(0,184,148,0.5); }
+  50% { box-shadow: 0 0 0 8px rgba(0,184,148,0); }
+}
+
+.theme-toggle {
+  background: var(--card); border: 1px solid var(--border); border-radius: 8px;
+  width: 40px; height: 40px; cursor: pointer; display: flex;
+  align-items: center; justify-content: center; font-size: 1.2rem;
+  transition: background var(--transition), border-color var(--transition);
+}
+
+.theme-toggle:hover { border-color: var(--text-secondary); }
+
+.card {
+  background: var(--card); border: 1px solid var(--border); border-radius: 12px;
+  padding: 20px; transition: background var(--transition), border-color var(--transition), box-shadow var(--transition);
+  box-shadow: var(--shadow);
+}
+
+.status-bar { margin-bottom: 24px; }
+
+.status-main {
+  display: flex; align-items: center; justify-content: space-between;
+  flex-wrap: wrap; gap: 12px; margin-bottom: 16px;
+}
+
+.status-text { font-size: 1.35rem; font-weight: 600; }
+
+.status-meta { display: flex; gap: 20px; flex-wrap: wrap; color: var(--text-secondary); font-size: 0.9rem; }
+
+.countdown-bar { margin-top: 12px; }
+
+.countdown-label { font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 6px; display: flex; justify-content: space-between; }
+
+.progress-track {
+  height: 6px; background: var(--border); border-radius: 3px; overflow: hidden;
+}
+
+.progress-fill {
+  height: 100%; background: var(--green); border-radius: 3px;
+  transition: width 1s linear;
+}
+
+.stats-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
+  gap: 16px; margin-bottom: 24px;
+}
+
+.stat-card { padding: 18px; }
+
+.stat-label { font-size: 0.8rem; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 0.5px; margin-bottom: 8px; }
+
+.stat-value { font-size: 1.7rem; font-weight: 700; }
+
+.stat-sub { font-size: 0.8rem; color: var(--text-secondary); margin-top: 4px; }
+
+.stat-card.green .stat-value { color: var(--green); }
+.stat-card.blue .stat-value { color: var(--blue); }
+.stat-card.yellow .stat-value { color: var(--yellow); }
+.stat-card.red .stat-value { color: var(--red); }
+.stat-card.purple .stat-value { color: var(--purple); }
+
+.section-card { margin-bottom: 24px; }
+.section-title { font-size: 1.05rem; font-weight: 600; margin-bottom: 16px; }
+
+.stacked-bar-container { margin-bottom: 20px; }
+
+.stacked-bar {
+  height: 32px; border-radius: 6px; overflow: hidden; display: flex;
+  background: var(--border);
+}
+
+.stacked-segment { height: 100%; transition: width 0.5s ease; min-width: 0; }
+
+.legend {
+  display: flex; gap: 16px; flex-wrap: wrap; margin-top: 10px;
+  font-size: 0.85rem; color: var(--text-secondary);
+}
+
+.legend-item { display: flex; align-items: center; gap: 6px; }
+
+.legend-dot { width: 10px; height: 10px; border-radius: 50%; }
+
+.toggle-group {
+  display: flex; gap: 4px; margin-bottom: 16px;
+  background: var(--border); border-radius: 8px; padding: 3px; width: fit-content;
+}
+
+.toggle-btn {
+  background: transparent; border: none; color: var(--text-secondary);
+  padding: 6px 14px; border-radius: 6px; cursor: pointer; font-size: 0.85rem;
+  transition: all var(--transition);
+}
+
+.toggle-btn.active { background: var(--card); color: var(--text); font-weight: 600; }
+
+.chart-area {
+  display: flex; align-items: flex-end; gap: 2px; height: 120px;
+  background: var(--chart-bg); border-radius: 8px; padding: 8px; overflow: hidden;
+}
+
+.chart-bar {
+  flex: 1; border-radius: 2px 2px 0 0; transition: height 0.3s ease, background 0.3s ease;
+  min-width: 3px; position: relative;
+}
+
+.chart-bar.ok { background: var(--green); }
+.chart-bar.fail { background: var(--red); }
+
+.chart-labels {
+  display: flex; justify-content: space-between; margin-top: 4px;
+  font-size: 0.7rem; color: var(--text-secondary);
+}
+
+.config-section { margin-bottom: 24px; }
+
+.copy-btn {
+  background: var(--green); color: #fff; border: none; border-radius: 8px;
+  padding: 8px 18px; cursor: pointer; font-size: 0.9rem; font-weight: 600;
+  transition: opacity var(--transition); margin-bottom: 16px;
+}
+
+.copy-btn:hover { opacity: 0.85; }
+.copy-btn.copied { background: var(--blue); }
+
+.config-table { width: 100%; border-collapse: collapse; }
+
+.config-table td {
+  padding: 10px 12px; border-bottom: 1px solid var(--border);
+  font-size: 0.9rem;
+}
+
+.config-table tr:last-child td { border-bottom: none; }
+
+.config-table td:first-child {
+  color: var(--text-secondary); font-weight: 500; width: 140px;
+  white-space: nowrap;
+}
+
+.config-table td:last-child { word-break: break-all; }
+
+.password-cell { display: flex; align-items: center; gap: 8px; }
+
+.password-text { flex: 1; }
+
+.eye-btn {
+  background: none; border: none; cursor: pointer; font-size: 1.1rem;
+  opacity: 0.6; transition: opacity var(--transition); padding: 4px;
+}
+
+.eye-btn:hover { opacity: 1; }
+
+.history-section { margin-bottom: 24px; }
+
+.timeline { display: flex; flex-direction: column; gap: 6px; max-height: 400px; overflow-y: auto; }
+
+.timeline-entry {
+  display: flex; align-items: center; gap: 10px; padding: 10px 14px;
+  border-radius: 8px; background: var(--chart-bg); font-size: 0.88rem;
+  transition: background var(--transition);
+}
+
+.entry-dot { width: 8px; height: 8px; border-radius: 50%; flex-shrink: 0; }
+
+.entry-dot.ok { background: var(--green); }
+.entry-dot.fail { background: var(--red); }
+
+.entry-time { color: var(--text-secondary); font-variant-numeric: tabular-nums; min-width: 60px; }
+
+.entry-msg { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
+
+.badge {
+  padding: 2px 8px; border-radius: 4px; font-size: 0.78rem; font-weight: 600;
+  white-space: nowrap;
+}
+
+.badge.added { background: rgba(0,184,148,0.15); color: var(--green); }
+.badge.updated { background: rgba(116,185,255,0.15); color: var(--blue); }
+.badge.skipped { background: rgba(139,144,160,0.15); color: var(--text-secondary); }
+.badge.error { background: rgba(225,112,85,0.15); color: var(--red); }
+
+.empty-state {
+  text-align: center; padding: 40px 20px; color: var(--text-secondary);
+  font-size: 0.95rem;
+}
+
+@media (max-width: 768px) {
+  .stats-grid { grid-template-columns: repeat(2, 1fr); }
+  .status-main { flex-direction: column; align-items: flex-start; }
+  .status-meta { flex-direction: column; gap: 4px; }
+}
+
+@media (max-width: 480px) {
+  .stats-grid { grid-template-columns: 1fr; }
+}
+</style>
+</head>
+<body>
+<div class="container">
+  <header>
+    <div class="logo">
+      <span class="status-dot" id="headerDot"></span>
+      Baikal Sync
+    </div>
+    <button class="theme-toggle" id="themeToggle" aria-label="Toggle theme">🌙</button>
+  </header>
+
+  <div class="card status-bar" id="statusBar">
+    <div class="empty-state">Loading…</div>
+  </div>
+
+  <div class="stats-grid" id="statsGrid">
+    <div class="card stat-card green"><div class="stat-label">Total Events</div><div class="stat-value" id="statEvents">—</div></div>
+    <div class="card stat-card blue"><div class="stat-label">Total Added</div><div class="stat-value" id="statAdded">—</div></div>
+    <div class="card stat-card purple"><div class="stat-label">Avg Events/Sync</div><div class="stat-value" id="statAvgEvents">—</div></div>
+    <div class="card stat-card blue"><div class="stat-label">Syncs Total</div><div class="stat-value" id="statSyncs">—</div><div class="stat-sub" id="statSyncsSub"></div></div>
+    <div class="card stat-card yellow"><div class="stat-label">Avg Sync Time</div><div class="stat-value" id="statAvgDuration">—</div></div>
+    <div class="card stat-card purple"><div class="stat-label">Avg Latency</div><div class="stat-value" id="statAvgLatency">—</div></div>
+    <div class="card stat-card green"><div class="stat-label">Bandwidth Saved</div><div class="stat-value" id="statBandwidth">—</div></div>
+    <div class="card stat-card" id="backoffCard"><div class="stat-label">Backoff</div><div class="stat-value" id="statBackoff">—</div></div>
+  </div>
+
+  <div class="card section-card">
+    <div class="section-title">Session Breakdown</div>
+    <div class="stacked-bar-container">
+      <div class="stacked-bar" id="stackedBar"></div>
+      <div class="legend" id="stackedLegend"></div>
+    </div>
+    <div class="toggle-group" id="chartToggle">
+      <button class="toggle-btn active" data-metric="duration">Duration</button>
+      <button class="toggle-btn" data-metric="events">Events</button>
+      <button class="toggle-btn" data-metric="latency">Latency</button>
+    </div>
+    <div class="chart-area" id="chartArea"></div>
+    <div class="chart-labels" id="chartLabels"></div>
+  </div>
+
+  <div class="card config-section">
+    <div class="section-title">Configuration</div>
+    <button class="copy-btn" id="copyBtn">Copy .env</button>
+    <table class="config-table" id="configTable">
+      <tbody id="configBody"></tbody>
+    </table>
+  </div>
+
+  <div class="card history-section">
+    <div class="section-title">Sync History</div>
+    <div class="timeline" id="timeline">
+      <div class="empty-state">No sync history yet.</div>
+    </div>
+  </div>
+</div>
+
+<script>
+(function () {
+  "use strict";
+
+  const state = {
+    data: null,
+    chartMetric: "duration",
+    passwordVisible: false,
+    pollTimer: null,
+    countdownTimer: null,
+    lastPoll: null
+  };
+
+  const $ = (sel) => document.querySelector(sel);
+
+  function fmtBytes(b) {
+    if (b == null || b === 0) return "0 B";
+    if (b >= 1048576) return (b / 1048576).toFixed(2) + " MB";
+    return (b / 1024).toFixed(1) + " KB";
+  }
+
+  function fmtUptime(sec) {
+    if (sec == null) return "—";
+    const h = Math.floor(sec / 3600);
+    const m = Math.floor((sec % 3600) / 60);
+    return h + "h " + m + "m";
+  }
+
+  function fmtDuration(s) {
+    if (s == null) return "—";
+    if (s < 1) return (s * 1000).toFixed(0) + "ms";
+    return s.toFixed(2) + "s";
+  }
+
+  function fmtTime(iso) {
+    if (!iso) return "Never";
+    try {
+      const d = new Date(iso);
+      return d.toLocaleTimeString();
+    } catch { return iso; }
+  }
+
+  function fmtCountdown(sec) {
+    if (sec == null || sec < 0) return "00:00";
+    const m = Math.floor(sec / 60);
+    const s = sec % 60;
+    return String(m).padStart(2, "0") + ":" + String(s).padStart(2, "0");
+  }
+
+  function truncate(str, max) {
+    if (!str) return "";
+    max = max || 60;
+    return str.length > max ? str.slice(0, 30) + "…" : str;
+  }
+
+  function maskPassword(p) {
+    if (!p) return "";
+    return "•".repeat(Math.min(p.length, 20));
+  }
+
+  function getStatusLabel(s) {
+    switch (s) {
+      case "syncing": return "Syncing…";
+      case "error": return "Error";
+      case "backoff": return "Backing off";
+      case "idle":
+      default: return "Up to Date";
+    }
+  }
+
+  function getSyncStatusClass(s) {
+    switch (s) {
+      case "syncing": return "syncing";
+      case "error": return "error";
+      case "backoff": return "backoff";
+      default: return "";
+    }
+  }
+
+  /* ── Theme ── */
+  function initTheme() {
+    const saved = localStorage.getItem("baikal-theme");
+    const theme = saved || "dark";
+    document.documentElement.setAttribute("data-theme", theme);
+    $("#themeToggle").textContent = theme === "dark" ? "☀️" : "🌙";
+  }
+
+  function toggleTheme() {
+    const current = document.documentElement.getAttribute("data-theme");
+    const next = current === "dark" ? "light" : "dark";
+    document.documentElement.setAttribute("data-theme", next);
+    localStorage.setItem("baikal-theme", next);
+    $("#themeToggle").textContent = next === "dark" ? "☀️" : "🌙";
+  }
+
+  /* ── Render Status Bar ── */
+  function renderStatusBar(d) {
+    const cls = getSyncStatusClass(d.status);
+    $("#headerDot").className = "status-dot" + (cls ? " " + cls : "");
+
+    let statusText = "";
+    if (d.status === "backoff" && d.next_sync_in != null) {
+      const mins = Math.ceil(d.next_sync_in / 60);
+      statusText = "Backing off — " + mins + " min remaining";
+    } else {
+      statusText = "Sync " + getStatusLabel(d.status);
+    }
+
+    const progressPct = d.next_sync_in != null && d.config && d.config.sync_frequency
+      ? Math.max(0, Math.min(100, ((d.config.sync_frequency * 60 - d.next_sync_in) / (d.config.sync_frequency * 60)) * 100))
+      : 0;
+
+    $("#statusBar").innerHTML =
+      '<div class="status-main">' +
+        '<div class="status-text">' + statusText + "</div>" +
+        '<div class="status-meta">' +
+          '<span>Last sync: ' + fmtTime(d.last_sync) + "</span>" +
+          (d.duration != null ? '<span>Duration: ' + fmtDuration(d.duration) + "</span>" : "") +
+          (d.ics_latency_ms != null ? '<span>Latency: ' + d.ics_latency_ms + "ms</span>" : "") +
+          '<span>Uptime: ' + fmtUptime(d.session.uptime_sec) + "</span>" +
+        "</div>" +
+      "</div>" +
+      '<div class="countdown-bar">' +
+        '<div class="countdown-label">' +
+          '<span>Next sync</span><span id="countdown">' + fmtCountdown(d.next_sync_in) + "</span>" +
+        "</div>" +
+        '<div class="progress-track"><div class="progress-fill" id="progressFill" style="width:' + progressPct + '%"></div></div>' +
+      "</div>";
+  }
+
+  /* ── Render Stats ── */
+  function renderStats(d) {
+    const s = d.session;
+    $("#statEvents").textContent = d.event_count != null ? d.event_count : "—";
+    $("#statAdded").textContent = s.total_added != null ? s.total_added : "—";
+
+    const totalOps = (s.total_added || 0) + (s.total_updated || 0);
+    const avgEvents = s.syncs_total > 0 ? (totalOps / s.syncs_total).toFixed(2) : "—";
+    $("#statAvgEvents").textContent = avgEvents;
+
+    $("#statSyncs").textContent = s.syncs_total || 0;
+    const skipPct = s.syncs_total > 0 ? ((s.syncs_skipped || 0) / s.syncs_total * 100).toFixed(0) : "0";
+    $("#statSyncsSub").textContent = (s.syncs_failed || 0) + " failed · " + skipPct + "% skipped";
+
+    $("#statAvgDuration").textContent = fmtDuration(s.avg_duration);
+    $("#statAvgLatency").textContent = s.avg_latency_ms != null ? s.avg_latency_ms + " ms" : "—";
+    $("#statBandwidth").textContent = fmtBytes(s.bandwidth_saved_bytes);
+
+    const bc = $("#backoffCard");
+    if (d.status === "backoff") {
+      bc.className = "card stat-card yellow";
+      const mins = Math.ceil((d.next_sync_in || 0) / 60);
+      $("#statBackoff").textContent = mins + " min";
+    } else {
+      bc.className = "card stat-card green";
+      $("#statBackoff").textContent = "None";
+    }
+  }
+
+  /* ── Render Stacked Bar ── */
+  function renderStackedBar(d) {
+    const s = d.session;
+    const added = s.total_added || 0;
+    const updated = s.total_updated || 0;
+    const deleted = s.total_deleted || 0;
+    const skipped = s.syncs_skipped || 0;
+    const total = added + updated + deleted + skipped || 1;
+
+    const w1 = (added / total * 100).toFixed(2);
+    const w2 = (updated / total * 100).toFixed(2);
+    const w3 = (deleted / total * 100).toFixed(2);
+    const w4 = (skipped / total * 100).toFixed(2);
+
+    $("#stackedBar").innerHTML =
+      '<div class="stacked-segment" style="width:' + w1 + '%;background:var(--green)"></div>' +
+      '<div class="stacked-segment" style="width:' + w2 + '%;background:var(--blue)"></div>' +
+      '<div class="stacked-segment" style="width:' + w3 + '%;background:var(--purple)"></div>' +
+      '<div class="stacked-segment" style="width:' + w4 + '%;background:var(--text-secondary)"></div>';
+
+    $("#stackedLegend").innerHTML =
+      '<div class="legend-item"><span class="legend-dot" style="background:var(--green)"></span>Added: ' + added + "</div>" +
+      '<div class="legend-item"><span class="legend-dot" style="background:var(--blue)"></span>Updated: ' + updated + "</div>" +
+      '<div class="legend-item"><span class="legend-dot" style="background:var(--purple)"></span>Deleted: " + deleted + "</div>" +
+      '<div class="legend-item"><span class="legend-dot" style="background:var(--text-secondary)"></span>Skipped: ' + skipped + "</div>";
+  }
+
+  /* ── Render Chart ── */
+  function renderChart(d) {
+    const history = d.session.history || [];
+    const metric = state.chartMetric;
+    const sliced = history.slice(-50);
+    if (!sliced.length) {
+      $("#chartArea").innerHTML = "";
+      $("#chartLabels").innerHTML = "";
+      return;
+    }
+
+    let key = "";
+    if (metric === "duration") key = "duration";
+    else if (metric === "events") {
+      const vals = sliced.map(function (e) { return (e.added || 0) + (e.updated || 0) + (e.deleted || 0); });
+      const maxVal = Math.max(1, ...vals);
+      const bars = sliced.map(function (e, i) {
+        const v = (e.added || 0) + (e.updated || 0) + (e.deleted || 0);
+        const h = Math.max(2, (v / maxVal) * 100);
+        return '<div class="chart-bar ' + (e.ok ? "ok" : "fail") + '" style="height:' + h + '%" title="' + v + ' events"></div>';
+      }).join("");
+      $("#chartArea").innerHTML = bars;
+      const first = sliced[0];
+      const last = sliced[sliced.length - 1];
+      $("#chartLabels").innerHTML = '<span>' + (first.time || "") + "</span><span>" + (last.time || "") + "</span>";
+      return;
+    } else { key = "latency_ms"; }
+
+    const vals = sliced.map(function (e) { return e[key] || 0; });
+    const maxVal = Math.max(1, ...vals);
+
+    const bars = sliced.map(function (e) {
+      const v = e[key] || 0;
+      const h = Math.max(2, (v / maxVal) * 100);
+      const tip = metric === "duration" ? (v * 1000).toFixed(0) + "ms" : v + "ms";
+      return '<div class="chart-bar ' + (e.ok ? "ok" : "fail") + '" style="height:' + h + '%" title="' + tip + '"></div>';
+    }).join("");
+
+    $("#chartArea").innerHTML = bars;
+    const first = sliced[0];
+    const last = sliced[sliced.length - 1];
+    $("#chartLabels").innerHTML = '<span>' + (first.time || "") + "</span><span>" + (last.time || "") + "</span>";
+  }
+
+  /* ── Render Config ── */
+  function renderConfig(d) {
+    const c = d.config || {};
+    const rows = [
+      ["ICS URL", truncate(c.ics_url || "")],
+      ["Baikal URL", truncate(c.baikal_url || "")],
+      ["User", c.baikal_user || ""],
+      ["Password", "password", c.baikal_pass || ""],
+      ["Frequency", c.sync_frequency ? c.sync_frequency + " minutes" : "—"],
+      ["Calendar ID", c.calendar_id || "—"]
+    ];
+
+    let html = "";
+    rows.forEach(function (r) {
+      if (r[1] === "password") {
+        const pw = state.passwordVisible ? r[2] : maskPassword(r[2]);
+        html += '<tr><td>' + r[0] + "</td><td>" +
+          '<div class="password-cell">' +
+          '<span class="password-text">' + pw + "</span>" +
+          '<button class="eye-btn" id="eyeBtn">' + (state.passwordVisible ? "🙈" : "👁️") + "</button>" +
+          "</div></td></tr>";
+      } else {
+        html += '<tr><td>' + r[0] + "</td><td>" + r[1] + "</td></tr>";
+      }
+    });
+    $("#configBody").innerHTML = html;
+
+    if ($("#eyeBtn")) {
+      $("#eyeBtn").addEventListener("click", function () {
+        state.passwordVisible = !state.passwordVisible;
+        renderConfig(state.data);
+      });
+    }
+  }
+
+  /* ── Render History ── */
+  function renderHistory(d) {
+    const history = d.session.history || [];
+    const sliced = history.slice(-50).reverse();
+    if (!sliced.length) {
+      $("#timeline").innerHTML = '<div class="empty-state">No sync history yet.</div>';
+      return;
+    }
+
+    let html = "";
+    sliced.forEach(function (entry) {
+      const ok = entry.ok !== false;
+      const badge = getBadge(entry);
+      html +=
+        '<div class="timeline-entry">' +
+          '<span class="entry-dot ' + (ok ? "ok" : "fail") + '"></span>' +
+          '<span class="entry-time">' + (entry.time || "") + "</span>" +
+          '<span class="entry-msg">' + escapeHtml(entry.msg || (ok ? "OK" : "Error")) + "</span>" +
+          badge +
+        "</div>";
+    });
+    $("#timeline").innerHTML = html;
+  }
+
+  function getBadge(e) {
+    const added = e.added || 0;
+    const updated = e.updated || 0;
+    const deleted = e.deleted || 0;
+    if (!e.ok) return '<span class="badge error">error</span>';
+    if (e.skipped || (added === 0 && updated === 0 && deleted === 0)) return '<span class="badge skipped">skipped</span>';
+    const parts = [];
+    if (added) parts.push("+" + added);
+    if (updated) parts.push("~" + updated);
+    if (deleted) parts.push("−" + deleted);
+    return '<span class="badge ' + (added ? "added" : "updated") + '">' + parts.join(" / ") + "</span>";
+  }
+
+  function escapeHtml(str) {
+    const div = document.createElement("div");
+    div.textContent = str;
+    return div.innerHTML;
+  }
+
+  /* ── Copy .env ── */
+  function copyEnv() {
+    const c = state.data.config;
+    if (!c) return;
+    const lines = [
+      "ICS_URL=" + (c.ics_url || ""),
+      "BAIKAL_URL=" + (c.baikal_url || ""),
+      "BAIKAL_USER=" + (c.baikal_user || ""),
+      "BAIKAL_PASS=" + (c.baikal_pass || ""),
+      "SYNC_FREQUENCY=" + (c.sync_frequency || ""),
+      "CALENDAR_ID=" + (c.calendar_id || "")
+    ].join("\n");
+
+    navigator.clipboard.writeText(lines).then(function () {
+      const btn = $("#copyBtn");
+      btn.textContent = "Copied!";
+      btn.classList.add("copied");
+      setTimeout(function () {
+        btn.textContent = "Copy .env";
+        btn.classList.remove("copied");
+      }, 2000);
+    }).catch(function () {
+      const ta = document.createElement("textarea");
+      ta.value = lines;
+      document.body.appendChild(ta);
+      ta.select();
+      document.execCommand("copy");
+      document.body.removeChild(ta);
+      const btn = $("#copyBtn");
+      btn.textContent = "Copied!";
+      btn.classList.add("copied");
+      setTimeout(function () {
+        btn.textContent = "Copy .env";
+        btn.classList.remove("copied");
+      }, 2000);
+    });
+  }
+
+  /* ── Polling ── */
+  function updateCountdown() {
+    if (!state.data) return;
+    const el = $("#countdown");
+    const fill = $("#progressFill");
+    if (!el || !fill) return;
+
+    let remaining = (state.data.next_sync_in || 0) - 1;
+    if (remaining < 0) remaining = 0;
+    el.textContent = fmtCountdown(remaining);
+
+    const freq = state.data.config ? state.data.config.sync_frequency * 60 : 600;
+    const pct = freq > 0 ? Math.max(0, Math.min(100, ((freq - remaining) / freq) * 100)) : 100;
+    fill.style.width = pct + "%";
+    state.data.next_sync_in = remaining;
+  }
+
+  async function poll() {
+    try {
+      const res = await fetch("/api/status");
+      if (!res.ok) throw new Error("HTTP " + res.status);
+      state.data = await res.json();
+      state.lastPoll = Date.now();
+      renderStatusBar(state.data);
+      renderStats(state.data);
+      renderStackedBar(state.data);
+      renderChart(state.data);
+      renderConfig(state.data);
+      renderHistory(state.data);
+    } catch (err) {
+      console.error("Poll error:", err);
+    }
+  }
+
+  /* ── Init ── */
+  function init() {
+    initTheme();
+    $("#themeToggle").addEventListener("click", toggleTheme);
+    $("#copyBtn").addEventListener("click", copyEnv);
+
+    document.getElementById("chartToggle").addEventListener("click", function (e) {
+      const btn = e.target.closest(".toggle-btn");
+      if (!btn) return;
+      state.chartMetric = btn.getAttribute("data-metric");
+      document.querySelectorAll("#chartToggle .toggle-btn").forEach(function (b) { b.classList.remove("active"); });
+      btn.classList.add("active");
+      if (state.data) renderChart(state.data);
+    });
+
+    poll();
+    state.pollTimer = setInterval(poll, 10000);
+    state.countdownTimer = setInterval(updateCountdown, 1000);
+  }
+
+  if (document.readyState === "loading") {
+    document.addEventListener("DOMContentLoaded", init);
+  } else {
+    init();
+  }
+})();
+</script>
+</body>
+</html>

sync_calendar.py

@@ -12,7 +12,8 @@ from config import validate, HEADERS, Config
 from state import SyncState
 from diff import parse_ics_events, compute_diff, parse_ics_events_with_data
 from apply import apply_adds, apply_updates, apply_deletes
-from health import HealthServer
+from health import HealthServer, SyncSession
+from dashboard import DashboardServer
 
 logger = logging.getLogger(__name__)
 shutdown_event = threading.Event()
@@ -51,8 +52,23 @@ def find_calendar(client, config):
     return None
 
 
-def sync_once(state: SyncState, health: HealthServer, config: Config) -> bool:
+def sync_once(
+    state: SyncState,
+    health: HealthServer,
+    session: SyncSession,
+    config: Config,
+    dashboard: DashboardServer,
+) -> bool:
     start_time = time.time()
+    ics_latency_ms = 0
+    added = 0
+    updated = 0
+    deleted = 0
+    skipped = False
+    ics_download_size = 0
+    msg = ""
+
+    dashboard.set_syncing(True)
     logger.info("Starting sync cycle...")
 
     try:
@@ -68,17 +84,35 @@ def sync_once(state: SyncState, health: HealthServer, config: Config) -> bool:
 
         if remote_etag and cached_etag == remote_etag:
             logger.info("No changes detected (ETag match). Skipping sync.")
+            duration = time.time() - start_time
+            skipped = True
+            msg = "no changes (ETag)"
+            session.record(True, duration, 0, 0, 0, True, 0, msg)
+            health.update_status(datetime.now(timezone.utc), duration, True, 0)
+            dashboard.set_syncing(False)
             return True
 
+        dl_start = time.time()
         response = requests.get(config.ics_url, headers=HEADERS, timeout=30)
         response.raise_for_status()
         ics_text = response.text
+        dl_end = time.time()
+        ics_latency_ms = round((dl_end - dl_start) * 1000)
+        ics_download_size = len(ics_text)
         ics_hash = hashlib.sha256(ics_text.encode("utf-8")).hexdigest()
 
         if cached_hash == ics_hash:
             logger.info("No changes detected (hash match). Skipping sync.")
             if remote_etag:
                 state.set_ics_cache(ics_hash, remote_etag)
+            duration = time.time() - start_time
+            skipped = True
+            msg = "no changes (hash)"
+            session.record(True, duration, 0, 0, 0, True, ics_latency_ms, msg, ics_download_size)
+            if ics_download_size:
+                pass
+            health.update_status(datetime.now(timezone.utc), duration, True, 0)
+            dashboard.set_syncing(False)
             return True
 
         state.set_ics_cache(ics_hash, remote_etag)
@@ -101,30 +135,29 @@ def sync_once(state: SyncState, health: HealthServer, config: Config) -> bool:
         if not to_add and not to_update and not to_delete:
             logger.info("Calendar is already in sync.")
             duration = time.time() - start_time
-            health.update_status(
-                datetime.now(timezone.utc),
-                duration,
-                True,
-                len(ics_uids),
-            )
+            skipped = True
+            msg = "already in sync"
+            session.record(True, duration, 0, 0, 0, True, ics_latency_ms, msg, ics_download_size)
             for uid, h in ics_uids.items():
                 state.upsert_event(uid, h)
+            health.update_status(datetime.now(timezone.utc), duration, True, len(ics_uids))
+            dashboard.set_event_count(len(ics_uids))
+            dashboard.set_syncing(False)
             return True
 
         if is_first_run and not to_delete:
             logger.info(
-                "First run detected: %d events in ICS. Registering state without re-adding to calendar.",
+                "First run detected: %d events in ICS. Registering state without re-adding.",
                 len(to_add),
             )
             for uid, h in ics_uids.items():
                 state.upsert_event(uid, h)
             duration = time.time() - start_time
-            health.update_status(
-                datetime.now(timezone.utc),
-                duration,
-                True,
-                len(ics_uids),
-            )
+            msg = f"first run, registered {len(to_add)} events"
+            session.record(True, duration, len(to_add), 0, 0, False, ics_latency_ms, msg, ics_download_size)
+            health.update_status(datetime.now(timezone.utc), duration, True, len(ics_uids))
+            dashboard.set_event_count(len(ics_uids))
+            dashboard.set_syncing(False)
             return True
 
         logger.info(
@@ -145,12 +178,10 @@ def sync_once(state: SyncState, health: HealthServer, config: Config) -> bool:
         if not calendar:
             logger.error("Failed to find calendar")
             duration = time.time() - start_time
-            health.update_status(
-                datetime.now(timezone.utc),
-                duration,
-                False,
-                0,
-            )
+            msg = "calendar not found"
+            session.record(False, duration, 0, 0, 0, False, ics_latency_ms, msg, ics_download_size)
+            health.update_status(datetime.now(timezone.utc), duration, False, 0)
+            dashboard.set_syncing(False)
             return False
 
         snapshot = state.snapshot()
@@ -162,19 +193,26 @@ def sync_once(state: SyncState, health: HealthServer, config: Config) -> bool:
 
         try:
             logger.info("Phase 1: Adding %d events...", len(add_events))
+            s_a, e_a = 0, 0
             if add_events:
-                s, e = apply_adds(calendar, add_events)
-                logger.info("Added %d/%d events (%d errors)", s, len(add_events), e)
+                s_a, e_a = apply_adds(calendar, add_events)
+                logger.info("Added %d/%d events (%d errors)", s_a, len(add_events), e_a)
 
             logger.info("Phase 2: Updating %d events...", len(update_events))
+            s_u, e_u = 0, 0
             if update_events:
-                s, e = apply_updates(calendar, update_events)
-                logger.info("Updated %d/%d events (%d errors)", s, len(update_events), e)
+                s_u, e_u = apply_updates(calendar, update_events)
+                logger.info("Updated %d/%d events (%d errors)", s_u, len(update_events), e_u)
 
             logger.info("Phase 3: Deleting %d events...", len(delete_uids))
+            s_d, e_d = 0, 0
             if delete_uids:
-                s, e = apply_deletes(calendar, delete_uids)
-                logger.info("Deleted %d/%d events (%d errors)", s, len(delete_uids), e)
+                s_d, e_d = apply_deletes(calendar, delete_uids)
+                logger.info("Deleted %d/%d events (%d errors)", s_d, len(delete_uids), e_d)
+
+            added = s_a
+            updated = s_u
+            deleted = s_d
 
             for uid, h in ics_uids.items():
                 state.upsert_event(uid, h)
@@ -184,36 +222,31 @@ def sync_once(state: SyncState, health: HealthServer, config: Config) -> bool:
 
             total = len(ics_uids)
             duration = time.time() - start_time
+            msg = f"+{added} / ~{updated} / -{deleted}"
+            session.record(True, duration, added, updated, deleted, False, ics_latency_ms, msg, ics_download_size)
             logger.info("Sync completed in %.1fs. Total events: %d", duration, total)
-            health.update_status(
-                datetime.now(timezone.utc),
-                duration,
-                True,
-                total,
-            )
+            health.update_status(datetime.now(timezone.utc), duration, True, total)
+            dashboard.set_event_count(total)
+            dashboard.set_syncing(False)
             return True
 
         except Exception as exc:
             logger.error("Sync failed: %s. Rolling back state.", exc)
             state.restore_snapshot(snapshot)
             duration = time.time() - start_time
-            health.update_status(
-                datetime.now(timezone.utc),
-                duration,
-                False,
-                0,
-            )
+            msg = str(exc)[:80]
+            session.record(False, duration, 0, 0, 0, False, ics_latency_ms, msg, ics_download_size)
+            health.update_status(datetime.now(timezone.utc), duration, False, 0)
+            dashboard.set_syncing(False)
             return False
 
     except Exception as exc:
         logger.error("Sync error: %s", exc)
         duration = time.time() - start_time
-        health.update_status(
-            datetime.now(timezone.utc),
-            duration,
-            False,
-            0,
-        )
+        msg = str(exc)[:80]
+        session.record(False, duration, 0, 0, 0, False, ics_latency_ms, msg, ics_download_size)
+        health.update_status(datetime.now(timezone.utc), duration, False, 0)
+        dashboard.set_syncing(False)
         return False
 
 
@@ -233,6 +266,19 @@ def main():
     health.start()
     logger.info("Health endpoint on :8081")
 
+    session = SyncSession()
+    dashboard = DashboardServer(8082, health, session)
+    dashboard.update_config({
+        "ics_url": config.ics_url,
+        "baikal_url": config.baikal_url,
+        "baikal_user": config.baikal_user,
+        "baikal_pass": config.baikal_pass,
+        "sync_frequency": config.sync_frequency,
+        "calendar_id": os.environ.get("CALENDAR_ID", ""),
+    })
+    dashboard.start()
+    logger.info("Dashboard on :8082")
+
     backoff = 0
 
     def handle_signal(signum, frame):
@@ -243,7 +289,7 @@ def main():
     signal.signal(signal.SIGINT, handle_signal)
 
     while not shutdown_event.is_set():
-        success = sync_once(state, health, config)
+        success = sync_once(state, health, session, config, dashboard)
 
         if success:
             backoff = 0
@@ -253,11 +299,14 @@ def main():
             sleep_time = backoff * 60
             logger.info("Sync failed. Backing off %d minutes...", backoff)
 
+        dashboard.set_next_sync_in(sleep_time)
+        dashboard.set_backoff_min(backoff)
         logger.info("Next sync in %d seconds...", sleep_time)
         shutdown_event.wait(sleep_time)
 
     state.close()
     health.stop()
+    dashboard.stop()
     logger.info("Shutdown complete.")