on-demand: Simplify OS-specific code for interface type selection

Previously, the enum values themselves were different for iOS and macOS.
With this commit, the enum values are common, and only how they're handled
is specific to iOS and macOS.

Signed-off-by: Roopesh Chander <roop@roopc.net>

4 files changed, 43 insertions, 71 deletions

diff --git a/WireGuard/WireGuard/Tunnel/ActivateOnDemandSetting.swift b/WireGuard/WireGuard/Tunnel/ActivateOnDemandSetting.swift
index 38359da..0cb3f98 100644
--- a/WireGuard/WireGuard/Tunnel/ActivateOnDemandSetting.swift
+++ b/WireGuard/WireGuard/Tunnel/ActivateOnDemandSetting.swift
@@ -10,18 +10,19 @@ struct ActivateOnDemandSetting {
 
 enum ActivateOnDemandOption {
     case none // Valid only when isActivateOnDemandEnabled is false
-    case useOnDemandOverWiFiOnly
-    #if os(iOS)
-    case useOnDemandOverWiFiOrCellular
-    case useOnDemandOverCellularOnly
-    #elseif os(macOS)
-    case useOnDemandOverWiFiOrEthernet
-    case useOnDemandOverEthernetOnly
-    #else
-    #error("Unimplemented")
-    #endif
+    case wiFiInterfaceOnly
+    case nonWiFiInterfaceOnly
+    case anyInterface
 }
 
+#if os(iOS)
+private let nonWiFiInterfaceType: NEOnDemandRuleInterfaceType = .cellular
+#elseif os(macOS)
+private let nonWiFiInterfaceType: NEOnDemandRuleInterfaceType = .ethernet
+#else
+#error("Unimplemented")
+#endif
+
 extension ActivateOnDemandSetting {
     func apply(on tunnelProviderManager: NETunnelProviderManager) {
         tunnelProviderManager.isOnDemandEnabled = isActivateOnDemandEnabled
@@ -31,48 +32,22 @@ extension ActivateOnDemandSetting {
         switch activateOnDemandOption {
         case .none:
             rules = nil
-        #if os(iOS)
-        case .useOnDemandOverWiFiOrCellular:
-            rules = [connectRule]
-        case .useOnDemandOverWiFiOnly:
+        case .wiFiInterfaceOnly:
             connectRule.interfaceTypeMatch = .wiFi
-            disconnectRule.interfaceTypeMatch = .cellular
+            disconnectRule.interfaceTypeMatch = nonWiFiInterfaceType
             rules = [connectRule, disconnectRule]
-        case .useOnDemandOverCellularOnly:
-            connectRule.interfaceTypeMatch = .cellular
+        case .nonWiFiInterfaceOnly:
+            connectRule.interfaceTypeMatch = nonWiFiInterfaceType
             disconnectRule.interfaceTypeMatch = .wiFi
             rules = [connectRule, disconnectRule]
-        #elseif os(macOS)
-        case .useOnDemandOverWiFiOrEthernet:
+        case .anyInterface:
             rules = [connectRule]
-        case .useOnDemandOverWiFiOnly:
-            connectRule.interfaceTypeMatch = .wiFi
-            disconnectRule.interfaceTypeMatch = .ethernet
-            rules = [connectRule, disconnectRule]
-        case .useOnDemandOverEthernetOnly:
-            connectRule.interfaceTypeMatch = .ethernet
-            disconnectRule.interfaceTypeMatch = .wiFi
-            rules = [connectRule, disconnectRule]
-        #else
-        #error("Unimplemented")
-        #endif
         }
         tunnelProviderManager.onDemandRules = rules
     }
 
     init(from tunnelProviderManager: NETunnelProviderManager) {
         let rules = tunnelProviderManager.onDemandRules ?? []
-        #if os(iOS)
-        let otherInterfaceType: NEOnDemandRuleInterfaceType = .cellular
-        let useWiFiOrOtherOption: ActivateOnDemandOption = .useOnDemandOverWiFiOrCellular
-        let useOtherOnlyOption: ActivateOnDemandOption = .useOnDemandOverCellularOnly
-        #elseif os(macOS)
-        let otherInterfaceType: NEOnDemandRuleInterfaceType = .ethernet
-        let useWiFiOrOtherOption: ActivateOnDemandOption = .useOnDemandOverWiFiOrEthernet
-        let useOtherOnlyOption: ActivateOnDemandOption = .useOnDemandOverEthernetOnly
-        #else
-        #error("Unimplemented")
-        #endif
         let activateOnDemandOption: ActivateOnDemandOption
         switch rules.count {
         case 0:
@@ -80,14 +55,14 @@ extension ActivateOnDemandSetting {
         case 1:
             let rule = rules[0]
             precondition(rule.action == .connect)
-            activateOnDemandOption = useWiFiOrOtherOption
+            activateOnDemandOption = .anyInterface
         case 2:
             let connectRule = rules.first(where: { $0.action == .connect })!
             let disconnectRule = rules.first(where: { $0.action == .disconnect })!
-            if connectRule.interfaceTypeMatch == .wiFi && disconnectRule.interfaceTypeMatch == otherInterfaceType {
-                activateOnDemandOption = .useOnDemandOverWiFiOnly
-            } else if connectRule.interfaceTypeMatch == otherInterfaceType && disconnectRule.interfaceTypeMatch == .wiFi {
-                activateOnDemandOption = useOtherOnlyOption
+            if connectRule.interfaceTypeMatch == .wiFi && disconnectRule.interfaceTypeMatch == nonWiFiInterfaceType {
+                activateOnDemandOption = .wiFiInterfaceOnly
+            } else if connectRule.interfaceTypeMatch == nonWiFiInterfaceType && disconnectRule.interfaceTypeMatch == .wiFi {
+                activateOnDemandOption = .nonWiFiInterfaceOnly
             } else {
                 fatalError("Unexpected onDemandRules set on tunnel provider manager")
             }
diff --git a/WireGuard/WireGuard/UI/TunnelViewModel.swift b/WireGuard/WireGuard/UI/TunnelViewModel.swift
index e6b00a1..8a9b007 100644
--- a/WireGuard/WireGuard/UI/TunnelViewModel.swift
+++ b/WireGuard/WireGuard/UI/TunnelViewModel.swift
@@ -627,21 +627,24 @@ extension TunnelViewModel {
         switch activateOnDemandOption {
         case .none:
             return tr("tunnelOnDemandOptionOff")
-        case .useOnDemandOverWiFiOnly:
+        case .wiFiInterfaceOnly:
             return tr("tunnelOnDemandOptionWiFiOnly")
-        #if os(iOS)
-        case .useOnDemandOverWiFiOrCellular:
-            return tr("tunnelOnDemandOptionWiFiOrCellular")
-        case .useOnDemandOverCellularOnly:
+        case .nonWiFiInterfaceOnly:
+            #if os(iOS)
             return tr("tunnelOnDemandOptionCellularOnly")
-        #elseif os(macOS)
-        case .useOnDemandOverWiFiOrEthernet:
-            return tr("tunnelOnDemandOptionWiFiOrEthernet")
-        case .useOnDemandOverEthernetOnly:
+            #elseif os(macOS)
             return tr("tunnelOnDemandOptionEthernetOnly")
-        #else
-        #error("Unimplemented")
-        #endif
+            #else
+            #error("Unimplemented")
+            #endif
+        case .anyInterface:
+            #if os(iOS)
+            return tr("tunnelOnDemandOptionWiFiOrCellular")
+            #elseif os(macOS)
+            return tr("tunnelOnDemandOptionWiFiOrEthernet")
+            #else
+            #error("Unimplemented")
+            #endif
         }
     }
 
@@ -658,13 +661,7 @@ extension TunnelViewModel {
     }
 
     static func defaultActivateOnDemandOption() -> ActivateOnDemandOption {
-        #if os(iOS)
-        return .useOnDemandOverWiFiOrCellular
-        #elseif os(macOS)
-        return .useOnDemandOverWiFiOrEthernet
-        #else
-        #error("Unimplemented")
-        #endif
+        return .anyInterface
     }
 }
 
diff --git a/WireGuard/WireGuard/UI/iOS/ViewController/TunnelEditTableViewController.swift b/WireGuard/WireGuard/UI/iOS/ViewController/TunnelEditTableViewController.swift
index a15d5fe..1a20ffe 100644
--- a/WireGuard/WireGuard/UI/iOS/ViewController/TunnelEditTableViewController.swift
+++ b/WireGuard/WireGuard/UI/iOS/ViewController/TunnelEditTableViewController.swift
@@ -44,9 +44,9 @@ class TunnelEditTableViewController: UITableViewController {
     ]
 
     let activateOnDemandOptions: [ActivateOnDemandOption] = [
-        .useOnDemandOverWiFiOrCellular,
-        .useOnDemandOverWiFiOnly,
-        .useOnDemandOverCellularOnly
+        .anyInterface,
+        .wiFiInterfaceOnly,
+        .nonWiFiInterfaceOnly
     ]
 
     let tunnelsManager: TunnelsManager
diff --git a/WireGuard/WireGuard/UI/macOS/ViewController/TunnelEditViewController.swift b/WireGuard/WireGuard/UI/macOS/ViewController/TunnelEditViewController.swift
index 6e4a23a..2c1c538 100644
--- a/WireGuard/WireGuard/UI/macOS/ViewController/TunnelEditViewController.swift
+++ b/WireGuard/WireGuard/UI/macOS/ViewController/TunnelEditViewController.swift
@@ -82,9 +82,9 @@ class TunnelEditViewController: NSViewController {
 
     let activateOnDemandOptions: [ActivateOnDemandOption] = [
         .none,
-        .useOnDemandOverWiFiOrEthernet,
-        .useOnDemandOverWiFiOnly,
-        .useOnDemandOverEthernetOnly
+        .anyInterface,
+        .wiFiInterfaceOnly,
+        .nonWiFiInterfaceOnly
     ]
 
     let tunnelsManager: TunnelsManager