iOS: expose onStart hook

ios/core/Sources/Player/HeadlessPlayer.swift

@@ -59,6 +59,9 @@ public protocol CoreHooks {
     /// Fired when the state changes
     var state: Hook<BaseFlowState> { get }
 
+    /// A hook to access the current flow
+    var onStart: Hook<FlowType> { get }
+
     /// Initialize hooks from reference to javascript core player
     init(from: JSValue)
 }

ios/core/Sources/Types/Core/FlowType.swift

@@ -0,0 +1,43 @@
+//
+//  FlowType.swift
+//  PlayerUI
+//
+//  Created by Zhao Xia Wu on 2025-03-05.
+//
+
+import Foundation
+import JavaScriptCore
+
+/**
+A wrapper around the JS FlowType in the core player
+The JSON payload for running Player, different from the Flow class which is the Flow Instance which contains the navigation state machine
+*/
+public class FlowType: CreatedFromJSValue {
+    /// Typealias for associated type
+    public typealias T = FlowType
+
+    /// The ID of this flow
+    public var id: String? { value.objectForKeyedSubscript("id")?.toString() }
+
+    /// The original data associated with this flow
+    public var data: [String: Any]? { value.objectForKeyedSubscript("data")?.toObject() as? [String: Any] }
+
+    /**
+    Creates an instance from a JSValue, used for generic construction
+    - parameters:
+       - value: The JSValue to construct from
+    */
+    public static func createInstance(value: JSValue) -> FlowType { FlowType(value) }
+
+    /// The JSValue that backs this wrapper
+    public private(set) var value: JSValue
+
+    /**
+    Construct a Flow from a JSValue
+    - parameters:
+       - value: The JSValue that is the Flow
+    */
+    public init(_ value: JSValue) {
+        self.value = value
+    }
+}

ios/core/Tests/FlowStateTests.swift

@@ -39,6 +39,12 @@ class FlowStateTests: XCTestCase {
     func testActionFlowState() {
         let player = HeadlessPlayerImpl(plugins: [])
         let hitActionNode = expectation(description: "ACTION state hit")
+
+        player.hooks?.onStart.tap { flow in
+            XCTAssertEqual(flow.id, "counter-flow")
+            XCTAssertEqual(flow.data as? [String: Int], ["count": 0])
+        }
+
         player.hooks?.flowController.tap({ flowController in
             flowController.hooks.flow.tap { flow in
                 flow.hooks.transition.tap { oldState, _ in

ios/internal-test-utils/Sources/FlowData.swift

@@ -122,6 +122,9 @@ public struct FlowData {
 {
   "id": "counter-flow",
   "views": [],
+  "data": {
+    "count": 0
+  },
   "navigation": {
     "BEGIN": "FLOW_1",
     "FLOW_1": {

ios/swiftui/Sources/SwiftUIPlayer.swift

@@ -288,6 +288,9 @@ public struct SwiftUIPlayerHooks: CoreHooks {
     /// Provide Transition Animation information for transition views in the same flow
     public var transition: SyncBailHook<Void, PlayerViewTransition>
 
+    /// Provides access to the current flow
+    public var onStart: Hook<FlowType>
+
     /// Initialize hooks from reference to javascript core player
     public init(from player: JSValue) {
         flowController = Hook<FlowController>(baseValue: player, name: "flowController")
@@ -296,6 +299,7 @@ public struct SwiftUIPlayerHooks: CoreHooks {
         state = Hook<BaseFlowState>(baseValue: player, name: "state")
         view = SyncWaterfallHook<AnyView>()
         transition = SyncBailHook<Void, PlayerViewTransition>()
+        onStart = Hook<FlowType>(baseValue: player, name: "onStart")
     }
 }
 

ios/test-utils-core/Sources/utilities/HeadlessPlayerImpl.swift

@@ -33,11 +33,14 @@ public class HeadlessHooks: CoreHooks {
 
     public var state: Hook<BaseFlowState>
 
+    public var onStart: Hook<FlowType>
+
     required public init(from value: JSValue) {
         flowController = Hook(baseValue: value, name: "flowController")
         viewController = Hook(baseValue: value, name: "viewController")
         dataController = Hook(baseValue: value, name: "dataController")
         state = Hook(baseValue: value, name: "state")
+        onStart = Hook<FlowType>(baseValue: value, name: "onStart")
     }
 }
 

ios/test-utils-core/Sources/utilities/TestPlayer.swift

@@ -48,10 +48,13 @@ public class TestHooks: CoreHooks {
 
     public var state: Hook<BaseFlowState>
 
+    public var onStart: Hook<FlowType>
+
     public required init(from player: JSValue) {
         flowController = Hook<FlowController>(baseValue: player, name: "flowController")
         viewController = Hook<ViewController>(baseValue: player, name: "viewController")
         dataController = Hook<DataController>(baseValue: player, name: "dataController")
         state = Hook<BaseFlowState>(baseValue: player, name: "state")
+        onStart = Hook<FlowType>(baseValue: player, name: "onStart")
     }
 }