Release 1.5.1

Bug fixes and code quality improvements:

- Fix mirror index dirtied on every sync (MirrorRecord.updatedAt in equality)
- Fix mirror URL corruption: encode calendar/source IDs before joining with ';'
  and use percentEncodedPath to prevent double-encoding
- Fix cleanup route mutating UI calendar picker selection unnecessarily
- Fix --exit flag redundancy (isCLIRun no longer implies termination)
- Remove dead SKIP_ALL_DAY_DEFAULT constant
- Replace deprecated FileHandle(forWritingAtPath:) with throwing variant
- Add EKEventStoreChanged observer for live calendar list refresh
- Extract AppLogStore into its own file (AppLogStore.swift)
- Add Block.span(start🔚) factory; replace verbose nil-field constructions
- Remove redundant MainActor.run{} wrappers inside @MainActor MirrorEngine
- Fix SettingsPayload indentation inside ContentView

All 45 unit tests pass.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

AGENTS.md

@@ -10,7 +10,7 @@ It is a single-platform macOS app written in **Swift 5** and **SwiftUI**, using
 
 Key capabilities:
 - Manual or route-driven multi-source mirroring
-- Privacy modes: hide details (placeholder title) or mark events Private server-side (best-effort)
+- Privacy mode: hide details (placeholder title)
 - DRY-RUN mode to preview changes without writing
 - Scheduled headless runs via a self-installed `launchd` LaunchAgent
 - Settings autosave/restore, plus Import/Export JSON
@@ -36,26 +36,26 @@ No external Swift Package Manager dependencies are used. The project is self-con
 ```
 BusyMirror/
 ├── BusyMirrorApp.swift          # App entry point; defines Window + MenuBarExtra
-├── ContentView.swift            # Main UI, mirror engine, settings, CLI, scheduling (≈2600 lines)
+├── ContentView.swift            # Main UI, settings, CLI, scheduling (≈1800 lines)
+├── MirrorEngine.swift           # EventKit mirror engine (read, deduplicate, merge, create/update/delete)
+├── MirrorConfig.swift           # Configuration struct passed to the engine
+├── MirrorUtils.swift            # URL builders, mirror detection, calendar labels
+├── BlockMath.swift              # Block merging, gap calculation, overlap logic (Block.span factory)
+├── EventFilters.swift           # Work-hours, title, and organizer filters
 ├── MenuBarSupport.swift         # `BusyMirrorAppController` (state coordinator) + menu bar view
+├── AppLogStore.swift            # File-backed log store with rotation (AppLogStore enum)
 ├── Info.plist                   # LSUIElement, calendar usage descriptions
 ├── BusyMirror.entitlements      # App sandbox + calendar access entitlement
 └── Assets.xcassets/             # AppIcon set and accent color
 
-BusyMirror.xcodeproj/            # Xcode project
-BusyMirrorTests/                 # Empty (no tests implemented)
-BusyMirrorUITests/               # Empty (no tests implemented)
+BusyMirror.xcodeproj/            # Xcode project (PBXFileSystemSynchronizedRootGroup — new .swift files are auto-included)
+BusyMirrorTests/                 # Unit tests: BlockMathTests, EventFiltersTests, MirrorUtilsTests (45 tests)
+BusyMirrorUITests/               # UI tests (empty)
 ```
 
-**Architecture note:** nearly all business logic lives inside `ContentView.swift`. This includes:
-- SwiftUI view body and subviews
-- EventKit mirror engine (read, deduplicate, merge, create/update/delete)
-- Settings serialization/deserialization
-- CLI argument parsing
-- `launchd` LaunchAgent installation/removal
-- Logging to file and UI
+**Architecture note:** `ContentView.swift` handles the SwiftUI view hierarchy, settings serialization, CLI argument parsing, `launchd` scheduling, and logging. The EventKit mirror engine lives in `MirrorEngine.swift` and is invoked from `ContentView` via `makeEngine()`. Pure helper logic (block math, filters, URL utilities) has been extracted into standalone files for testability.
 
-When making changes, be aware that `ContentView.swift` is a large monolithic file. Extracting helpers is fine, but keep the existing data flow ( `@EnvironmentObject`, `@AppStorage`, `@State`) intact.
+When making changes, keep the existing data flow (`@EnvironmentObject`, `@AppStorage`, `@State`) intact in `ContentView.swift`.
 
 ## Build and Release Commands
 
@@ -96,8 +96,8 @@ Built products:
 
 ## Testing
 
-- **There are no implemented tests.** `BusyMirrorTests/` and `BusyMirrorUITests/` exist as Xcode targets but contain no source files.
-- When adding logic, prefer extracting pure functions (e.g., block merging, gap calculation, filter logic) so they can be unit-tested later.
+- Unit tests exist in `BusyMirrorTests/` for `BlockMath`, `EventFilters`, and `MirrorUtils`.
+- When adding logic, prefer extracting pure functions (e.g., block merging, gap calculation, filter logic) so they can be unit-tested.
 - Manual testing checklist for releases:
   1. Grant Calendar permission.
   2. Select a source and target, run DRY-RUN, verify log output.
@@ -112,7 +112,6 @@ Built products:
 - **Calendar data:** the app reads and writes the user’s calendars via EventKit. It must handle permission denial gracefully.
 - **Sandbox:** the app uses the macOS app sandbox (`com.apple.security.app-sandbox`) and the `com.apple.security.personal-information.calendars` entitlement.
 - **Signing:** releases are ad-hoc signed only (`codesign --sign -`). They are **not notarized**. Gatekeeper may block the app on first launch; users may need to right-click → Open.
-- **Private events:** the "Mark Private" feature uses Objective-C runtime tricks (`perform(Selector:)`, KVC `setValue:forKey:`) because EventKit does not expose a public privacy API. This is best-effort and may silently fail on some calendar providers (e.g., some Exchange configurations).
 - **Loop guard:** a `sessionGuard` set prevents mirroring an event into the same target twice in one run, and prefix-based detection (`titlePrefix`) prevents re-mirroring already-mirrored placeholders.
 - **Logging:** log files are written to the user’s `~/Library/Logs/BusyMirror/`. No log data is transmitted externally.
 
@@ -136,9 +135,15 @@ Scheduled runs are implemented by generating a `launchd` plist in `~/Library/Lau
 
 | File | Purpose |
 |------|---------|
-| `BusyMirror/ContentView.swift` | UI, business logic, mirror engine, settings, CLI, scheduling |
+| `BusyMirror/ContentView.swift` | UI, settings, CLI, scheduling |
+| `BusyMirror/MirrorEngine.swift` | EventKit mirror engine (runMirror, runCleanup, index persistence) |
+| `BusyMirror/MirrorConfig.swift` | Configuration struct for mirror runs |
+| `BusyMirror/MirrorUtils.swift` | Mirror URL builders, event detection, calendar labels |
+| `BusyMirror/BlockMath.swift` | Block merging, gap calculation, overlap logic |
+| `BusyMirror/EventFilters.swift` | Work-hours, title, and organizer filters |
 | `BusyMirror/BusyMirrorApp.swift` | App struct, window scene, menu-bar extra |
 | `BusyMirror/MenuBarSupport.swift` | `@MainActor` app controller + menu bar SwiftUI view |
+| `BusyMirror/AppLogStore.swift` | File-backed log with rotation (`~/Library/Logs/BusyMirror/`) |
 | `BusyMirror/Info.plist` | `LSUIElement`, calendar usage descriptions |
 | `BusyMirror/BusyMirror.entitlements` | Sandbox + calendar entitlement |
 | `Makefile` | Reproducible build, sign, and package targets |
@@ -149,6 +154,6 @@ Scheduled runs are implemented by generating a `launchd` plist in `~/Library/Lau
 
 - Do **not** add third-party dependencies unless the user explicitly asks. The project intentionally has zero external packages.
 - If you refactor `ContentView.swift`, preserve `@AppStorage` keys and `UserDefaults` keys exactly; users have existing settings on disk.
-- The mirror engine is tightly coupled to SwiftUI state. Extract helpers for testability, but do not break the `@MainActor`/`@State` flow without careful review.
+- The mirror engine (`MirrorEngine.swift`) is `@MainActor` and accepts an `EKEventStore` plus a logging closure. It does not directly mutate SwiftUI `@State`; `ContentView` manages all view state.
 - When modifying build settings, update both Debug and Release configurations in `project.pbxproj`, and update `CHANGELOG.md` if the change is user-visible.
 - Do not run `git commit`, `git push`, or similar operations unless explicitly asked.

BusyMirror-1.5.1-macOS.zip.sha256

@@ -0,0 +1 @@
+9fd864e05f5091cbc23864ff226e7d909119a22e019584279a95d206b935cf15

BusyMirror.xcodeproj/project.pbxproj

@@ -410,7 +410,7 @@
 				"CODE_SIGN_IDENTITY[sdk=macosx*]" = "-";
 				CODE_SIGN_STYLE = Automatic;
 				COMBINE_HIDPI_IMAGES = YES;
-				CURRENT_PROJECT_VERSION = 18;
+				CURRENT_PROJECT_VERSION = 20;
 				ENABLE_PREVIEWS = YES;
 				GENERATE_INFOPLIST_FILE = YES;
 				INFOPLIST_FILE = BusyMirror/Info.plist;
@@ -421,7 +421,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-                MARKETING_VERSION = 1.4.0;
+                MARKETING_VERSION = 1.5.1;
 				PRODUCT_BUNDLE_IDENTIFIER = com.cqrenet.BusyMirror;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				REGISTER_APP_GROUPS = YES;
@@ -440,7 +440,7 @@
 				"CODE_SIGN_IDENTITY[sdk=macosx*]" = "-";
 				CODE_SIGN_STYLE = Automatic;
 				COMBINE_HIDPI_IMAGES = YES;
-				CURRENT_PROJECT_VERSION = 18;
+				CURRENT_PROJECT_VERSION = 20;
 				ENABLE_PREVIEWS = YES;
 				GENERATE_INFOPLIST_FILE = YES;
 				INFOPLIST_FILE = BusyMirror/Info.plist;
@@ -451,7 +451,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-                MARKETING_VERSION = 1.4.0;
+                MARKETING_VERSION = 1.5.1;
 				PRODUCT_BUNDLE_IDENTIFIER = com.cqrenet.BusyMirror;
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				REGISTER_APP_GROUPS = YES;

BusyMirror/AppLogStore.swift

@@ -0,0 +1,51 @@
+import Foundation
+
+enum AppLogStore {
+    private static let queue = DispatchQueue(label: "BusyMirror.log.store")
+    private static let maxLogSizeBytes: UInt64 = 1_000_000
+
+    static let logDirectoryURL: URL = {
+        let base = FileManager.default.urls(for: .libraryDirectory, in: .userDomainMask).first
+            ?? FileManager.default.homeDirectoryForCurrentUser.appendingPathComponent("Library", isDirectory: true)
+        return base.appendingPathComponent("Logs/BusyMirror", isDirectory: true)
+    }()
+
+    static let logFileURL = logDirectoryURL.appendingPathComponent("BusyMirror.log", isDirectory: false)
+    private static let archivedLogFileURL = logDirectoryURL.appendingPathComponent("BusyMirror.previous.log", isDirectory: false)
+    static let launchdStdoutURL = logDirectoryURL.appendingPathComponent("launchd.stdout.log", isDirectory: false)
+    static let launchdStderrURL = logDirectoryURL.appendingPathComponent("launchd.stderr.log", isDirectory: false)
+
+    private static let timestampFormatter: ISO8601DateFormatter = {
+        let f = ISO8601DateFormatter()
+        f.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
+        return f
+    }()
+
+    static func append(_ message: String) {
+        let line = "[\(timestampFormatter.string(from: Date()))] \(message)\n"
+        queue.async {
+            let fm = FileManager.default
+            do {
+                try fm.createDirectory(at: logDirectoryURL, withIntermediateDirectories: true)
+                if let attrs = try? fm.attributesOfItem(atPath: logFileURL.path),
+                   let size = attrs[.size] as? NSNumber,
+                   size.uint64Value >= maxLogSizeBytes {
+                    try? fm.removeItem(at: archivedLogFileURL)
+                    try? fm.moveItem(at: logFileURL, to: archivedLogFileURL)
+                }
+                if !fm.fileExists(atPath: logFileURL.path) {
+                    fm.createFile(atPath: logFileURL.path, contents: nil)
+                }
+                guard let data = line.data(using: .utf8) else { return }
+                // Use the throwing initialiser so we don't silently swallow
+                // an inaccessible file — the outer catch handles it.
+                let handle = try FileHandle(forWritingTo: logFileURL)
+                defer { try? handle.close() }
+                try handle.seekToEnd()
+                try handle.write(contentsOf: data)
+            } catch {
+                // Logging must never break the app's main behavior.
+            }
+        }
+    }
+}

BusyMirror/BlockMath.swift

@@ -7,6 +7,11 @@ struct Block: Hashable {
     let label: String?        // source title (for dry-run / non-private)
     let notes: String?        // source notes (for optional copy)
     let occurrence: Date?     // occurrenceDate for recurring instances
+
+    /// Convenience factory for time-only blocks (used internally for occupancy tracking).
+    static func span(start: Date, end: Date) -> Block {
+        Block(start: start, end: end, srcStableID: nil, label: nil, notes: nil, occurrence: nil)
+    }
 }
 
 // De-dup blocks by occurrence (preferred) or by time range
@@ -30,14 +35,14 @@ func mergeBlocks(_ blocks: [Block], gapMinutes: Int) -> [Block] {
     guard !blocks.isEmpty else { return [] }
     let sorted = blocks.sorted { $0.start < $1.start }
     var out: [Block] = []
-    var cur = Block(start: sorted[0].start, end: sorted[0].end, srcStableID: nil, label: nil, notes: nil, occurrence: nil)
+    var cur = Block.span(start: sorted[0].start, end: sorted[0].end)
     for b in sorted.dropFirst() {
         let gap = b.start.timeIntervalSince(cur.end) / 60.0
         if gap <= Double(gapMinutes) {
-            if b.end > cur.end { cur = Block(start: cur.start, end: b.end, srcStableID: nil, label: nil, notes: nil, occurrence: nil) }
+            if b.end > cur.end { cur = Block.span(start: cur.start, end: b.end) }
         } else {
             out.append(cur)
-            cur = Block(start: b.start, end: b.end, srcStableID: nil, label: nil, notes: nil, occurrence: nil)
+            cur = Block.span(start: b.start, end: b.end)
         }
     }
     out.append(cur)
@@ -55,21 +60,21 @@ func fullyCovered(_ mergedSegs: [Block], block: Block, tolMin: Double) -> Bool {
 }
 
 func gapsWithin(_ mergedSegs: [Block], in block: Block) -> [Block] {
-    if mergedSegs.isEmpty { return [Block(start: block.start, end: block.end, srcStableID: nil, label: nil, notes: nil, occurrence: nil)] }
+    if mergedSegs.isEmpty { return [Block.span(start: block.start, end: block.end)] }
     var segs: [Block] = []
     for s in mergedSegs where s.end > block.start && s.start < block.end {
         let ss = max(s.start, block.start)
         let ee = min(s.end, block.end)
-        if ee > ss { segs.append(Block(start: ss, end: ee, srcStableID: nil, label: nil, notes: nil, occurrence: nil)) }
+        if ee > ss { segs.append(Block.span(start: ss, end: ee)) }
     }
-    if segs.isEmpty { return [Block(start: block.start, end: block.end, srcStableID: nil, label: nil, notes: nil, occurrence: nil)] }
+    if segs.isEmpty { return [Block.span(start: block.start, end: block.end)] }
     let merged = coalesce(segs)
     var gaps: [Block] = []
     var prevEnd = block.start
     for s in merged {
-        if s.start > prevEnd { gaps.append(Block(start: prevEnd, end: s.start, srcStableID: nil, label: nil, notes: nil, occurrence: nil)) }
+        if s.start > prevEnd { gaps.append(Block.span(start: prevEnd, end: s.start)) }
         if s.end > prevEnd { prevEnd = s.end }
     }
-    if prevEnd < block.end { gaps.append(Block(start: prevEnd, end: block.end, srcStableID: nil, label: nil, notes: nil, occurrence: nil)) }
+    if prevEnd < block.end { gaps.append(Block.span(start: prevEnd, end: block.end)) }
     return gaps
 }

BusyMirror/MirrorConfig.swift

@@ -7,7 +7,6 @@ struct MirrorConfig {
     let mergeGapMin: Int
     let hideDetails: Bool
     let copyDescription: Bool
-    let markPrivate: Bool
     let mirrorAllDay: Bool
     let overlapMode: OverlapMode
     let titlePrefix: String

BusyMirror/MirrorEngine.swift

@@ -0,0 +1,626 @@
+import Foundation
+import EventKit
+
+private let SAME_TIME_TOL_MIN: Double = 5
+
+struct MirrorRecord: Hashable, Codable {
+    var targetCalendarID: String
+    var sourceCalendarID: String
+    var sourceStableID: String
+    var occurrenceTimestamp: TimeInterval?
+    var targetEventIdentifier: String?
+    var lastKnownStartTimestamp: TimeInterval
+    var lastKnownEndTimestamp: TimeInterval
+    var updatedAt: Date = Date()
+
+    // updatedAt is intentionally excluded from equality and hashing: it is a
+    // bookkeeping timestamp that changes on every write and should not cause
+    // the mirror index to be marked dirty when the meaningful fields are equal.
+    static func == (lhs: MirrorRecord, rhs: MirrorRecord) -> Bool {
+        lhs.targetCalendarID == rhs.targetCalendarID &&
+        lhs.sourceCalendarID == rhs.sourceCalendarID &&
+        lhs.sourceStableID == rhs.sourceStableID &&
+        lhs.occurrenceTimestamp == rhs.occurrenceTimestamp &&
+        lhs.targetEventIdentifier == rhs.targetEventIdentifier &&
+        lhs.lastKnownStartTimestamp == rhs.lastKnownStartTimestamp &&
+        lhs.lastKnownEndTimestamp == rhs.lastKnownEndTimestamp
+    }
+
+    func hash(into hasher: inout Hasher) {
+        hasher.combine(targetCalendarID)
+        hasher.combine(sourceCalendarID)
+        hasher.combine(sourceStableID)
+        hasher.combine(occurrenceTimestamp)
+        hasher.combine(targetEventIdentifier)
+        hasher.combine(lastKnownStartTimestamp)
+        hasher.combine(lastKnownEndTimestamp)
+    }
+
+    var sourceKey: String {
+        sourceOccurrenceKey(
+            sourceCalID: sourceCalendarID,
+            sourceStableID: sourceStableID,
+            occurrence: occurrenceTimestamp.map { Date(timeIntervalSince1970: $0) }
+        )
+    }
+
+    var timeKey: String {
+        "\(lastKnownStartTimestamp)|\(lastKnownEndTimestamp)"
+    }
+}
+
+@MainActor
+final class MirrorEngine {
+    private let log: (String) -> Void
+    private let mirrorIndexDefaultsKey = "mirror-index.v1"
+
+    init(log: @escaping (String) -> Void) {
+        self.log = log
+    }
+
+    private func loadMirrorIndex() -> [String: MirrorRecord] {
+        guard let data = UserDefaults.standard.data(forKey: mirrorIndexDefaultsKey) else { return [:] }
+        do {
+            return try JSONDecoder().decode([String: MirrorRecord].self, from: data)
+        } catch {
+            log("✗ Failed to load mirror index: \(error.localizedDescription)")
+            return [:]
+        }
+    }
+
+    private func saveMirrorIndex(_ index: [String: MirrorRecord]) {
+        do {
+            let data = try JSONEncoder().encode(index)
+            UserDefaults.standard.set(data, forKey: mirrorIndexDefaultsKey)
+        } catch {
+            log("✗ Failed to save mirror index: \(error.localizedDescription)")
+        }
+    }
+
+    func runMirror(
+        store: EKEventStore,
+        config: MirrorConfig,
+        sourceCalendar: EKCalendar,
+        targetCalendars: [EKCalendar],
+        sessionGuard: inout Set<String>,
+        isMultiRouteRun: Bool
+    ) async {
+        let srcCal = sourceCalendar
+        let srcName = calLabel(srcCal)
+        let targets = targetCalendars.filter { $0.calendarIdentifier != srcCal.calendarIdentifier }
+        if targets.isEmpty {
+            log("No target calendars selected. Choose at least one target or add a route with valid targets.")
+            return
+        }
+
+        let cal = Calendar.current
+        let todayStart = cal.startOfDay(for: Date())
+        let windowStart = cal.date(byAdding: .day, value: -config.daysBack, to: todayStart)!
+        let windowEnd = cal.date(byAdding: .day, value: config.daysForward, to: todayStart)!
+        log("=== BusyMirror ===")
+        log("Source: \(srcName)  Targets: \(targets.map { calLabel($0) }.joined(separator: ", "))")
+        log("Window: \(windowStart) -> \(windowEnd)")
+        log("WRITE: \(config.writeEnabled) \(config.writeEnabled ? "" : "(DRY-RUN)")  mode: \(config.overlapMode.rawValue)  mergeGapMin: \(config.mergeGapMin)  allDay: \(config.mirrorAllDay)")
+        log("Route: \(srcName) → {\(targets.map { calLabel($0) }.joined(separator: ", "))}")
+
+        // Source events (recurrences expanded by EventKit)
+        let srcPred = store.predicateForEvents(withStart: windowStart, end: windowEnd, calendars: [srcCal])
+        var srcEvents = store.events(matching: srcPred)
+        let srcFetched = srcEvents.count
+        srcEvents = srcEvents.filter { $0.calendar.calendarIdentifier == srcCal.calendarIdentifier }
+        let srcKept = srcEvents.count
+        if srcKept != srcFetched {
+            log("- WARN: filtered \(srcFetched - srcKept) stray source event(s) not in \(srcName)")
+        }
+        srcEvents.sort { ($0.startDate ?? .distantPast) < ($1.startDate ?? .distantPast) }
+
+        var srcBlocks: [Block] = []
+        var skippedMirrors = 0
+        let titleFilters = config.excludedTitleFilterTerms
+        let organizerFilters = config.excludedOrganizerFilterTerms
+        let enforceWorkHours = config.filterByWorkHours && config.workHoursEnd > config.workHoursStart
+        let allowedStartMinutes = config.workHoursStart * 60
+        let allowedEndMinutes = config.workHoursEnd * 60
+        var skippedWorkHours = 0
+        var skippedTitles = 0
+        var skippedOrganizers = 0
+        var skippedStatus = 0
+        for ev in srcEvents {
+            if Task.isCancelled { break }
+            if config.mirrorAcceptedOnly, ev.hasAttendees {
+                let attendees = ev.attendees ?? []
+                if let me = attendees.first(where: { $0.isCurrentUser }) {
+                    if me.participantStatus != .accepted {
+                        skippedStatus += 1
+                        continue
+                    }
+                } else {
+                    skippedStatus += 1
+                    continue
+                }
+            }
+            if enforceWorkHours, !ev.isAllDay, let start = ev.startDate,
+               isOutsideWorkHours(start, calendar: cal, startMinutes: allowedStartMinutes, endMinutes: allowedEndMinutes) {
+                skippedWorkHours += 1
+                continue
+            }
+            if shouldSkip(title: ev.title, filters: titleFilters, titlePrefix: config.titlePrefix) {
+                skippedTitles += 1
+                continue
+            }
+            if shouldSkipOrganizer(organizerValues: organizerStrings(for: ev), filters: organizerFilters) {
+                skippedOrganizers += 1
+                continue
+            }
+            if !config.mirrorAllDay && ev.isAllDay { continue }
+            if isMirrorEvent(ev, prefix: config.titlePrefix, placeholder: config.placeholderTitle) {
+                skippedMirrors += 1
+                continue
+            }
+            guard let s = ev.startDate, let e = ev.endDate, e > s else { continue }
+            guard ev.calendar.calendarIdentifier == srcCal.calendarIdentifier else { continue }
+            let srcID = stableSourceIdentifier(for: ev)
+            srcBlocks.append(Block(start: s, end: e, srcStableID: srcID, label: ev.title, notes: ev.notes, occurrence: ev.occurrenceDate))
+        }
+        if skippedMirrors > 0 {
+            log("- SKIP mirrored-on-source: \(skippedMirrors) instance(s)")
+        }
+        if skippedWorkHours > 0 {
+            log("- SKIP outside work hours: \(skippedWorkHours) event(s)")
+        }
+        if skippedTitles > 0 {
+            log("- SKIP title filter: \(skippedTitles) event(s)")
+        }
+        if skippedOrganizers > 0 {
+            log("- SKIP organizer filter: \(skippedOrganizers) event(s)")
+        }
+        if skippedStatus > 0 {
+            log("- SKIP non-accepted status: \(skippedStatus) event(s)")
+        }
+        srcBlocks = uniqueBlocks(srcBlocks, trackByID: config.mergeGapMin == 0)
+
+        let baseBlocks = (config.mergeGapMin > 0) ? mergeBlocks(srcBlocks, gapMinutes: config.mergeGapMin) : srcBlocks
+        let trackByID = (config.mergeGapMin == 0)
+        var mirrorIndex = loadMirrorIndex()
+        var mirrorIndexChanged = false
+
+        func sourceKey(for blk: Block) -> String? {
+            guard trackByID, let sid = blk.srcStableID else { return nil }
+            return sourceOccurrenceKey(sourceCalID: srcCal.calendarIdentifier, sourceStableID: sid, occurrence: blk.occurrence)
+        }
+
+        // Cache target events across routes when possible
+        var targetEventCache: [String: [EKEvent]] = [:]
+        for tgt in targets {
+            if Task.isCancelled { break }
+            let tgtName = calLabel(tgt)
+            log(">>> Target: \(tgtName)")
+            if tgt.calendarIdentifier == srcCal.calendarIdentifier {
+                log("- SKIP target is same as source: \(tgtName)")
+                continue
+            }
+            let tgtEvents: [EKEvent]
+            if let cached = targetEventCache[tgt.calendarIdentifier] {
+                tgtEvents = cached
+            } else {
+                let tgtPred = store.predicateForEvents(withStart: windowStart, end: windowEnd, calendars: [tgt])
+                var evs = store.events(matching: tgtPred)
+                let tgtFetched = evs.count
+                evs = evs.filter { $0.calendar.calendarIdentifier == tgt.calendarIdentifier }
+                if tgtFetched != evs.count {
+                    log("- WARN: filtered \(tgtFetched - evs.count) stray target event(s) not in \(tgtName)")
+                }
+                targetEventCache[tgt.calendarIdentifier] = evs
+                tgtEvents = evs
+            }
+
+            var placeholderSet = Set<String>()
+            var occupied: [Block] = []
+            var placeholdersBySourceKey: [String: EKEvent] = [:]
+            var placeholdersByTime: [String: EKEvent] = [:]
+            var targetEventsByIdentifier: [String: EKEvent] = [:]
+            for tv in tgtEvents {
+                guard tv.calendar.calendarIdentifier == tgt.calendarIdentifier else { continue }
+                if let eid = tv.eventIdentifier {
+                    targetEventsByIdentifier[eid] = tv
+                }
+                if let ts = tv.startDate, let te = tv.endDate {
+                    let timeKey = mirrorTimeKey(start: ts, end: te)
+                    if isMirrorEvent(tv, prefix: config.titlePrefix, placeholder: config.placeholderTitle) {
+                        placeholderSet.insert(timeKey)
+                        placeholdersByTime[timeKey] = tv
+                        let parsed = parseMirrorURL(tv.url)
+                        if let sourceCalID = parsed.sourceCalID,
+                           let sourceStableID = parsed.sourceStableID,
+                           !sourceCalID.isEmpty,
+                           !sourceStableID.isEmpty {
+                            let key = sourceOccurrenceKey(sourceCalID: sourceCalID, sourceStableID: sourceStableID, occurrence: parsed.occ)
+                            placeholdersBySourceKey[key] = tv
+                            let recordKey = mirrorRecordKey(targetCalID: tgt.calendarIdentifier, sourceKey: key)
+                            let record = MirrorRecord(
+                                targetCalendarID: tgt.calendarIdentifier,
+                                sourceCalendarID: sourceCalID,
+                                sourceStableID: sourceStableID,
+                                occurrenceTimestamp: parsed.occ?.timeIntervalSince1970,
+                                targetEventIdentifier: tv.eventIdentifier,
+                                lastKnownStartTimestamp: ts.timeIntervalSince1970,
+                                lastKnownEndTimestamp: te.timeIntervalSince1970
+                            )
+                            if mirrorIndex[recordKey] != record {
+                                mirrorIndex[recordKey] = record
+                                mirrorIndexChanged = true
+                            }
+                        }
+                    }
+                    occupied.append(Block.span(start: ts, end: te))
+                }
+            }
+            occupied = coalesce(occupied)
+
+            var created = 0
+            var skipped = 0
+            var updated = 0
+
+            func guardKey(for blk: Block, targetID: String) -> String {
+                if let key = sourceKey(for: blk) {
+                    return "\(key)|\(targetID)"
+                }
+                return "\(srcCal.calendarIdentifier)|\(blk.start.timeIntervalSince1970)|\(blk.end.timeIntervalSince1970)|\(targetID)"
+            }
+
+            func desiredNotes(for blk: Block) -> String? {
+                (!config.hideDetails && config.copyDescription) ? blk.notes : nil
+            }
+
+            func upsertMirrorRecord(for blk: Block, event: EKEvent) {
+                guard let sid = blk.srcStableID,
+                      let key = sourceKey(for: blk),
+                      let startDate = event.startDate,
+                      let endDate = event.endDate else { return }
+                let recordKey = mirrorRecordKey(targetCalID: tgt.calendarIdentifier, sourceKey: key)
+                let record = MirrorRecord(
+                    targetCalendarID: tgt.calendarIdentifier,
+                    sourceCalendarID: srcCal.calendarIdentifier,
+                    sourceStableID: sid,
+                    occurrenceTimestamp: blk.occurrence?.timeIntervalSince1970,
+                    targetEventIdentifier: event.eventIdentifier,
+                    lastKnownStartTimestamp: startDate.timeIntervalSince1970,
+                    lastKnownEndTimestamp: endDate.timeIntervalSince1970
+                )
+                if mirrorIndex[recordKey] != record {
+                    mirrorIndex[recordKey] = record
+                    mirrorIndexChanged = true
+                }
+            }
+
+            func removeMirrorRecord(for key: String) {
+                let recordKey = mirrorRecordKey(targetCalID: tgt.calendarIdentifier, sourceKey: key)
+                if mirrorIndex.removeValue(forKey: recordKey) != nil {
+                    mirrorIndexChanged = true
+                }
+            }
+
+            func resolveMappedEvent(for record: MirrorRecord) -> EKEvent? {
+                if let eid = record.targetEventIdentifier,
+                   let event = targetEventsByIdentifier[eid],
+                   event.calendar.calendarIdentifier == tgt.calendarIdentifier {
+                    return event
+                }
+                return placeholdersByTime[record.timeKey]
+            }
+
+            func rememberMirrorEvent(_ event: EKEvent, for blk: Block) {
+                if let startDate = event.startDate, let endDate = event.endDate {
+                    let timeKey = mirrorTimeKey(start: startDate, end: endDate)
+                    placeholderSet.insert(timeKey)
+                    placeholdersByTime[timeKey] = event
+                }
+                if let key = sourceKey(for: blk) {
+                    placeholdersBySourceKey[key] = event
+                }
+                if let eid = event.eventIdentifier {
+                    targetEventsByIdentifier[eid] = event
+                }
+                upsertMirrorRecord(for: blk, event: event)
+            }
+
+            func needsUpdate(existing: EKEvent, blk: Block, displayTitle: String, desiredNotes: String?, desiredURL: URL?) -> Bool {
+                let curS = existing.startDate ?? blk.start
+                let curE = existing.endDate ?? blk.end
+                if abs(curS.timeIntervalSince(blk.start)) > SAME_TIME_TOL_MIN * 60 { return true }
+                if abs(curE.timeIntervalSince(blk.end)) > SAME_TIME_TOL_MIN * 60 { return true }
+                if (existing.title ?? "") != displayTitle { return true }
+                if (existing.notes ?? "") != (desiredNotes ?? "") { return true }
+                if existing.isAllDay { return true }
+                if (existing.url?.absoluteString ?? "") != (desiredURL?.absoluteString ?? "") { return true }
+                return false
+            }
+
+            func createOrUpdateIfNeeded(_ blk: Block) async {
+                let gKey = guardKey(for: blk, targetID: tgt.calendarIdentifier)
+                if sessionGuard.contains(gKey) {
+                    skipped += 1
+                    log("- SKIP loop-guard [\(srcName) -> \(tgtName)] \(blk.start) -> \(blk.end)")
+                    return
+                }
+
+                let baseSourceTitle = stripPrefix(blk.label, prefix: config.titlePrefix)
+                let effectiveTitle = config.hideDetails ? config.placeholderTitle : (baseSourceTitle.isEmpty ? config.placeholderTitle : baseSourceTitle)
+                let titleSuffix = config.hideDetails ? "" : (baseSourceTitle.isEmpty ? "" : " — \(baseSourceTitle)")
+                let displayTitle = (config.titlePrefix.isEmpty ? "" : config.titlePrefix) + effectiveTitle
+                let notes = desiredNotes(for: blk)
+                let desiredURL = buildMirrorURL(
+                    targetCalID: tgt.calendarIdentifier,
+                    sourceCalID: srcCal.calendarIdentifier,
+                    sourceStableID: blk.srcStableID,
+                    occurrence: blk.occurrence,
+                    start: blk.start,
+                    end: blk.end
+                )
+                let exactTimeKey = mirrorTimeKey(start: blk.start, end: blk.end)
+                let blkSourceKey = sourceKey(for: blk)
+
+                func updateExisting(_ existing: EKEvent, byTime: Bool) async {
+                    let curS = existing.startDate ?? blk.start
+                    let curE = existing.endDate ?? blk.end
+                    rememberMirrorEvent(existing, for: blk)
+                    if !needsUpdate(existing: existing, blk: blk, displayTitle: displayTitle, desiredNotes: notes, desiredURL: desiredURL) {
+                        sessionGuard.insert(gKey)
+                        skipped += 1
+                        return
+                    }
+                    let byTimeSuffix = byTime ? " (by time)" : ""
+                    if !config.writeEnabled {
+                        sessionGuard.insert(gKey)
+                        log("~ WOULD UPDATE [\(srcName) -> \(tgtName)]\(byTimeSuffix) \(curS) -> \(curE)  TO  \(blk.start) -> \(blk.end)\(titleSuffix) [title: \(displayTitle)]")
+                        updated += 1
+                        return
+                    }
+                    existing.title = displayTitle
+                    existing.startDate = blk.start
+                    existing.endDate = blk.end
+                    existing.isAllDay = false
+                    existing.notes = notes
+                    existing.url = desiredURL
+                    do {
+                        try store.save(existing, span: .thisEvent, commit: true)
+                        log("✓ UPDATED [\(srcName) -> \(tgtName)]\(byTimeSuffix) \(blk.start) -> \(blk.end)")
+                        rememberMirrorEvent(existing, for: blk)
+                        occupied = coalesce(occupied + [Block.span(start: blk.start, end: blk.end)])
+                        sessionGuard.insert(gKey)
+                        updated += 1
+                    } catch {
+                        log("Update failed: \(error.localizedDescription)")
+                    }
+                }
+
+                if let blkSourceKey,
+                   let record = mirrorIndex[mirrorRecordKey(targetCalID: tgt.calendarIdentifier, sourceKey: blkSourceKey)],
+                   let existing = resolveMappedEvent(for: record) {
+                    await updateExisting(existing, byTime: false)
+                    return
+                }
+
+                if let blkSourceKey, let existing = placeholdersBySourceKey[blkSourceKey] {
+                    await updateExisting(existing, byTime: false)
+                    return
+                }
+
+                if let existingByTime = placeholdersByTime[exactTimeKey] {
+                    await updateExisting(existingByTime, byTime: true)
+                    return
+                }
+
+                if placeholderSet.contains(exactTimeKey) {
+                    skipped += 1
+                    return
+                }
+                if !config.writeEnabled {
+                    sessionGuard.insert(gKey)
+                    log("+ WOULD CREATE [\(srcName) -> \(tgtName)] \(blk.start) -> \(blk.end)\(titleSuffix) [title: \(displayTitle)]")
+                    return
+                }
+                guard tgt.calendarIdentifier != srcCal.calendarIdentifier else {
+                    skipped += 1
+                    log("- SKIP invariant: target is source [\(srcName)]")
+                    return
+                }
+                let newEv = EKEvent(eventStore: store)
+                newEv.calendar = tgt
+                newEv.title = displayTitle
+                newEv.startDate = blk.start
+                newEv.endDate = blk.end
+                newEv.isAllDay = false
+                newEv.notes = notes
+                newEv.url = desiredURL
+                newEv.availability = .busy
+                do {
+                    try store.save(newEv, span: .thisEvent, commit: true)
+                    created += 1
+                    log("✓ CREATED [\(srcName) -> \(tgtName)] \(blk.start) -> \(blk.end)")
+                    rememberMirrorEvent(newEv, for: blk)
+                    occupied = coalesce(occupied + [Block.span(start: blk.start, end: blk.end)])
+                    sessionGuard.insert(gKey)
+                } catch {
+                    log("Save failed: \(error.localizedDescription)")
+                }
+            }
+
+            for b in baseBlocks {
+                if Task.isCancelled { break }
+                switch config.overlapMode {
+                case .allow:
+                    await createOrUpdateIfNeeded(b)
+                case .skipCovered:
+                    if fullyCovered(occupied, block: b, tolMin: SAME_TIME_TOL_MIN) {
+                        log("- SKIP covered [\(srcName) -> \(tgtName)] \(b.start) -> \(b.end)")
+                        skipped += 1
+                    } else {
+                        await createOrUpdateIfNeeded(b)
+                    }
+                case .fillGaps:
+                    let gaps = gapsWithin(occupied, in: b)
+                    if gaps.isEmpty {
+                        log("- SKIP no gaps [\(srcName) -> \(tgtName)] \(b.start) -> \(b.end)")
+                        skipped += 1
+                    } else {
+                        for g in gaps { await createOrUpdateIfNeeded(g) }
+                    }
+                }
+            }
+            log("[Summary → \(tgtName)] created=\(created), updated=\(updated), skipped=\(skipped)")
+            if config.autoDeleteMissing {
+                let activeSourceKeys = Set(baseBlocks.compactMap { sourceKey(for: $0) })
+                let validTimeKeys = Set(baseBlocks.map { mirrorTimeKey(start: $0.start, end: $0.end) })
+
+                var byID: [String: EKEvent] = [:]
+                for tv in placeholdersByTime.values {
+                    guard tv.calendar.calendarIdentifier == tgt.calendarIdentifier else { continue }
+                    if let eid = tv.eventIdentifier { byID[eid] = tv }
+                }
+
+                var removed = 0
+                var skippedOtherSource = 0
+                var skippedLegacyNoURL = 0
+                var handledEventIDs = Set<String>()
+
+                let staleMirrorRecords = mirrorIndex.filter {
+                    $0.value.targetCalendarID == tgt.calendarIdentifier &&
+                    $0.value.sourceCalendarID == srcCal.calendarIdentifier &&
+                    !activeSourceKeys.contains($0.value.sourceKey)
+                }
+
+                for (recordKey, record) in staleMirrorRecords {
+                    if Task.isCancelled { break }
+                    let candidate = resolveMappedEvent(for: record)
+                    if let candidate {
+                        if !config.writeEnabled {
+                            log("~ WOULD DELETE (missing source) [\(srcName) -> \(tgtName)] \(candidate.startDate ?? windowStart) -> \(candidate.endDate ?? windowEnd)")
+                        } else {
+                            do {
+                                try store.remove(candidate, span: .thisEvent, commit: true)
+                                removed += 1
+                            } catch {
+                                log("Delete failed: \(error.localizedDescription)")
+                            }
+                        }
+                        if let eid = candidate.eventIdentifier {
+                            handledEventIDs.insert(eid)
+                        }
+                    }
+                    if config.writeEnabled || candidate == nil {
+                        if mirrorIndex.removeValue(forKey: recordKey) != nil {
+                            mirrorIndexChanged = true
+                        }
+                    }
+                }
+
+                for ev in byID.values {
+                    if Task.isCancelled { break }
+                    if let eid = ev.eventIdentifier, handledEventIDs.contains(eid) {
+                        continue
+                    }
+                    let parsed = parseMirrorURL(ev.url)
+                    var shouldDelete = false
+                    var parsedSourceKey: String? = nil
+                    if let sourceCalID = parsed.sourceCalID, !sourceCalID.isEmpty {
+                        if sourceCalID != srcCal.calendarIdentifier {
+                            skippedOtherSource += 1
+                            continue
+                        }
+                        if let sourceStableID = parsed.sourceStableID, !sourceStableID.isEmpty {
+                            let key = sourceOccurrenceKey(sourceCalID: sourceCalID, sourceStableID: sourceStableID, occurrence: parsed.occ)
+                            parsedSourceKey = key
+                            if !activeSourceKeys.contains(key) { shouldDelete = true }
+                        } else if trackByID,
+                                  let s = ev.startDate,
+                                  let e = ev.endDate,
+                                  !validTimeKeys.contains(mirrorTimeKey(start: s, end: e)) {
+                            shouldDelete = true
+                        }
+                    } else if trackByID && !isMultiRouteRun {
+                        if let s = ev.startDate,
+                           let e = ev.endDate,
+                           !validTimeKeys.contains(mirrorTimeKey(start: s, end: e)) {
+                            shouldDelete = true
+                        }
+                    } else if trackByID && isMultiRouteRun {
+                        let hasMapping = mirrorIndex.values.contains {
+                            $0.targetCalendarID == tgt.calendarIdentifier &&
+                            $0.sourceCalendarID == srcCal.calendarIdentifier &&
+                            $0.targetEventIdentifier == ev.eventIdentifier
+                        }
+                        if !hasMapping {
+                            skippedLegacyNoURL += 1
+                        }
+                        continue
+                    }
+                    if shouldDelete {
+                        if !config.writeEnabled {
+                            log("~ WOULD DELETE (missing source) [\(srcName) -> \(tgtName)] \(ev.startDate ?? windowStart) -> \(ev.endDate ?? windowEnd)")
+                        } else {
+                            do {
+                                try store.remove(ev, span: .thisEvent, commit: true)
+                                removed += 1
+                            } catch {
+                                log("Delete failed: \(error.localizedDescription)")
+                            }
+                        }
+                        if let key = parsedSourceKey {
+                            removeMirrorRecord(for: key)
+                        }
+                    }
+                }
+                if removed > 0 { log("[Cleanup missing for \(tgtName)] deleted=\(removed)") }
+                if skippedOtherSource > 0 {
+                    log("- INFO cleanup skipped \(skippedOtherSource) placeholders from other source routes on \(tgtName)")
+                }
+                if skippedLegacyNoURL > 0 {
+                    log("- INFO cleanup skipped \(skippedLegacyNoURL) unmanaged legacy placeholders without source metadata on \(tgtName)")
+                }
+            }
+        }
+        if mirrorIndexChanged {
+            saveMirrorIndex(mirrorIndex)
+        }
+    }
+
+    func runCleanup(
+        store: EKEventStore,
+        daysBack: Int,
+        daysForward: Int,
+        sourceCalendar: EKCalendar,
+        targetCalendars: [EKCalendar],
+        titlePrefix: String,
+        placeholderTitle: String,
+        writeEnabled: Bool
+    ) async {
+        let cal = Calendar.current
+        let todayStart = cal.startOfDay(for: Date())
+        let windowStart = cal.date(byAdding: .day, value: -daysBack, to: todayStart)!
+        let windowEnd = cal.date(byAdding: .day, value: daysForward, to: todayStart)!
+        log("=== Cleanup Busy placeholders in window ===")
+        log("(Cleanup is SAFE: mirrored events detected by url prefix or title prefix ‘\(titlePrefix)’)")
+        log("Window: \(windowStart) -> \(windowEnd)")
+
+        for tgt in targetCalendars {
+            let tgtPred = store.predicateForEvents(withStart: windowStart, end: windowEnd, calendars: [tgt])
+            let tgtEvents = store.events(matching: tgtPred)
+            var delCount = 0
+            for ev in tgtEvents {
+                guard isMirrorEvent(ev, prefix: titlePrefix, placeholder: placeholderTitle) else { continue }
+                if !writeEnabled {
+                    log("~ WOULD DELETE [\(tgt.title)] \(ev.startDate ?? todayStart) -> \(ev.endDate ?? todayStart)")
+                } else {
+                    do {
+                        try store.remove(ev, span: .thisEvent, commit: true)
+                        delCount += 1
+                    } catch {
+                        log("Delete failed: \(error.localizedDescription)")
+                    }
+                }
+            }
+            log("[Cleanup \(tgt.title)] deleted=\(delCount)")
+        }
+    }
+}

BusyMirror/MirrorUtils.swift

@@ -1,6 +1,12 @@
 import Foundation
 import EventKit
 
+// Calendar label helper to disambiguate identical names
+func calLabel(_ cal: EKCalendar) -> String {
+    let src = cal.source.title
+    return src.isEmpty ? cal.title : "\(cal.title) — \(src)"
+}
+
 // Remove our prefix when building titles so it never doubles up
 func stripPrefix(_ title: String?, prefix: String) -> String {
     guard let t = title else { return "" }
@@ -51,10 +57,12 @@ func mirrorTimeKey(start: Date, end: Date) -> String {
 func buildMirrorURL(targetCalID: String, sourceCalID: String, sourceStableID: String?, occurrence: Date?, start: Date, end: Date) -> URL? {
     let sourceID = sourceStableID ?? ""
     let occ = occurrence.map { String($0.timeIntervalSince1970) } ?? "-"
+    // Percent-encode IDs so that any embedded ";" doesn't corrupt the
+    // semicolon-delimited path when the URL is later parsed.
     let parts = [
-        targetCalID,
-        sourceCalID,
-        sourceID,
+        mirrorURLComponentEncode(targetCalID),
+        mirrorURLComponentEncode(sourceCalID),
+        mirrorURLComponentEncode(sourceID),
         occ,
         String(start.timeIntervalSince1970),
         String(end.timeIntervalSince1970)
@@ -62,7 +70,9 @@ func buildMirrorURL(targetCalID: String, sourceCalID: String, sourceStableID: St
     var components = URLComponents()
     components.scheme = "mirror"
     components.host = "x"
-    components.path = "/" + parts.joined(separator: ";")
+    // Use percentEncodedPath so URLComponents does not re-encode the already
+    // percent-encoded IDs (double-encoding would break round-trip parsing).
+    components.percentEncodedPath = "/" + parts.joined(separator: ";")
     return components.url
 }
 

CHANGELOG.md

@@ -2,6 +2,41 @@
 
 All notable changes to BusyMirror will be documented in this file.
 
+## [1.5.1] - 2026-05-27
+
+### Fixed
+- **Mirror index dirtied on every sync**: `MirrorRecord` used synthesized `Equatable` which included `updatedAt: Date = Date()`. Because `updatedAt` is set to the current time whenever a record is constructed, the comparison used to detect changes always returned "not equal", causing `UserDefaults` to be written on every sync run even when nothing changed. A custom `==` / `hash(into:)` now excludes `updatedAt`. ([MirrorEngine.swift](BusyMirror/MirrorEngine.swift))
+- **Mirror URL corruption with special characters in calendar IDs**: `buildMirrorURL` placed raw calendar and source IDs into the URL path without percent-encoding them. If any ID contained the `;` separator character the resulting URL would be mis-parsed on the next sync. `mirrorURLComponentEncode` (which already existed and was tested) is now called on all ID fields before they are joined. The path is set via `percentEncodedPath` to prevent `URLComponents` from double-encoding the already-encoded values. ([MirrorUtils.swift](BusyMirror/MirrorUtils.swift))
+- **Dead constant**: removed unused `SKIP_ALL_DAY_DEFAULT = true` from `ContentView.swift`.
+- **Deprecated `FileHandle` API**: replaced `FileHandle(forWritingAtPath:)` + `handle.closeFile()` with the modern throwing `FileHandle(forWritingTo:)`, `handle.seekToEnd()`, and `handle.write(contentsOf:)` in `AppLogStore`. ([AppLogStore.swift](BusyMirror/AppLogStore.swift))
+- **Cleanup jumps calendar picker**: `runCleanupForRoute` was mutating `sourceIndex`, `sourceID`, and `targetIDs` during route cleanup, visibly shifting the picker in the UI. Cleanup does not need to update the UI selection; those mutations are removed.
+- **`--exit` flag redundancy**: `NSApp.terminate` was called whenever `isCLIRun` was true, making `--exit` a no-op. The app now exits only when `--exit` is explicitly passed, so `--routes` / `--run-saved-routes` can be used without forcing termination.
+
+### Added
+- **Live calendar refresh**: the calendar list now updates automatically when the system calendar database changes (`EKEventStoreChanged` notification), removing the need to press "Refresh Calendars" after adding or removing a calendar. The observer is unregistered on view disappear and re-registered when the `EKEventStore` is recreated. ([ContentView.swift](BusyMirror/ContentView.swift))
+
+### Changed
+- **`AppLogStore` extracted**: moved from an inline private enum in `ContentView.swift` to its own file `AppLogStore.swift` for easier navigation. ([AppLogStore.swift](BusyMirror/AppLogStore.swift))
+- **`Block.span` factory**: added `Block.span(start:end:)` to replace the repetitive `Block(start:end:srcStableID:nil:label:nil:notes:nil:occurrence:nil)` construction pattern throughout `BlockMath.swift` and `MirrorEngine.swift`. ([BlockMath.swift](BusyMirror/BlockMath.swift))
+- **Removed redundant `MainActor.run` wrappers**: `MirrorEngine` is `@MainActor`; wrapping `store.save` / `store.remove` in `try await MainActor.run { }` was unnecessary and added overhead. ([MirrorEngine.swift](BusyMirror/MirrorEngine.swift))
+- **`SettingsPayload` indentation**: the nested struct was de-dented to column 0 inside `ContentView`, making it look like a top-level type. Indentation is now consistent with the surrounding members.
+
+### Build
+- Bump version to **1.5.1** (build **20**).
+
+## [1.5.0] - 2026-05-27
+
+### Removed
+- **Mark Private feature**: removed the non-functional server-side "Private" flagging for mirrored events. The Objective-C runtime hack (`setPrivate:`, KVC on `sensitivity`/`classification`) never worked reliably and would have blocked App Store review. This simplifies the UI and removes a private-API liability.
+
+### Changed
+- **Extracted mirror engine**: the ~500-line `runMirror` and `runCleanup` logic has been moved from `ContentView.swift` into a new `MirrorEngine.swift` class. `ContentView` now delegates to the engine via `makeEngine()`.
+- `MirrorRecord`, mirror index persistence, and `SAME_TIME_TOL_MIN` now live in the engine module.
+- `calLabel` moved to `MirrorUtils.swift` so it can be shared between UI and engine.
+
+### Build
+- Bump version to **1.5.0** (build **19**).
+
 ## [1.4.0] - 2026-05-27
 
 ### Fixed

ReleaseNotes-1.5.1.md

@@ -0,0 +1,21 @@
+# BusyMirror 1.5.1
+
+## Bug fixes
+
+- **Mirror index written on every sync** — `MirrorRecord`'s synthesized equality check included an `updatedAt` timestamp that is always set to the current date when a record is constructed. This meant every sync run marked the index as dirty and rewrote it to `UserDefaults`, even when no mirror events changed. Fixed with a custom `==` that ignores `updatedAt`.
+
+- **Mirror URLs corrupted by special characters in calendar IDs** — Calendar and source IDs placed into the `mirror://` URL were not percent-encoded before joining with `;`. An ID containing `;` would cause the URL to be mis-parsed on the next sync, potentially losing the link between a placeholder and its source event. IDs are now encoded with `mirrorURLComponentEncode` (already present and tested since 1.4.0) and the URL path is assigned via `percentEncodedPath` to prevent double-encoding.
+
+- **Calendar picker jumped during route cleanup** — Running "Cleanup Placeholders" over saved routes changed the source/target picker selection for each route. Cleanup no longer mutates the UI selection.
+
+- **`--exit` flag was always implied** — Using `--routes` or `--run-saved-routes` always terminated the app, making `--exit` redundant. The app now exits only when `--exit` is explicitly passed.
+
+## Improvements
+
+- **Live calendar refresh** — The calendar list now updates automatically when the system calendar database changes (new account added, calendar renamed, etc.), without requiring a manual "Refresh Calendars" press.
+
+- `AppLogStore` extracted into its own file; deprecated `FileHandle` API replaced with the modern throwing variant.
+
+- `Block.span(start:end:)` convenience factory added to `BlockMath`, eliminating repetitive nil-field construction.
+
+- Redundant `MainActor.run {}` wrappers removed from `MirrorEngine` (already running on `@MainActor`).