From 82e4fa9d2a5fb2940ad4bc72f2aa3c803ed287fc Mon Sep 17 00:00:00 2001
From: scttbnsn <80784472+scttbnsn@users.noreply.github.com>
Date: Tue, 10 Nov 2026 15:01:46 -0500
Subject: [PATCH] fix(triggers): retain rules when the legacy projection is
 missing

---
 Sources/DilatedCore/TriggerStore.swift        |  1 +
 .../DilatedCoreTests/TriggerStoreTests.swift  | 28 +++++++++++++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 Tests/DilatedCoreTests/TriggerStoreTests.swift

diff --git a/Sources/DilatedCore/TriggerStore.swift b/Sources/DilatedCore/TriggerStore.swift
index e6101f2..227c5dc 100644
--- a/Sources/DilatedCore/TriggerStore.swift
+++ b/Sources/DilatedCore/TriggerStore.swift
@@ -32,6 +32,7 @@ public struct TriggerStore: Sendable {
       try persist(record.rules, previous: legacy)
       return record.rules
     }
+    guard FileManager.default.fileExists(atPath: legacyFile.path) else { return record.rules }
     let baseline = Dictionary(uniqueKeysWithValues: record.legacy.map { ($0.id, $0) })
     let current = Dictionary(uniqueKeysWithValues: legacy.map { ($0.id, $0) })
     var rules = record.rules.filter { baseline[$0.id] == nil || current[$0.id] != nil }
diff --git a/Tests/DilatedCoreTests/TriggerStoreTests.swift b/Tests/DilatedCoreTests/TriggerStoreTests.swift
new file mode 100644
index 0000000..d2e22a9
--- /dev/null
+++ b/Tests/DilatedCoreTests/TriggerStoreTests.swift
@@ -0,0 +1,28 @@
+import Foundation
+import Testing
+
+@testable import DilatedCore
+
+struct TriggerStoreTests {
+  @Test(arguments: [false, true])
+  func missingProjectionPreservesRulesWhileAnEmptyProjectionDeletesThem(missing: Bool) throws {
+    let directory = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString)
+    defer { try? FileManager.default.removeItem(at: directory) }
+    let store = TriggerStore(directory: directory)
+    let rule = TriggerRule(name: "AC", criteria: [.power(onBattery: false)])
+    try store.save([rule])
+    let projection = directory.appendingPathComponent("triggers.json")
+    if missing {
+      try FileManager.default.removeItem(at: projection)
+    } else {
+      try JSONEncoder().encode([TriggerRule]()).write(to: projection, options: .atomic)
+    }
+    let expected = missing ? [rule] : []
+    let loaded = try store.load()
+    #expect(loaded == expected)
+    try store.save(loaded)
+    #expect(try store.load() == expected)
+    #expect(
+      try JSONDecoder().decode([TriggerRule].self, from: Data(contentsOf: projection)) == expected)
+  }
+}