From de3d14dc41f20006ace53f80b0c79208379cf6aa Mon Sep 17 00:00:00 2001
From: InsanusMokrassar <ovsyannikov.alexey95@gmail.com>
Date: Wed, 3 Nov 2021 15:36:25 +0600
Subject: [PATCH] solution of #109

---
 CHANGELOG.md                                      |  3 +++
 ...ateHandlerHolder.kt => StatesHandlerHolder.kt} | 15 +++++++++++++--
 .../inmo/micro_utils/fsm/common/StatesMachine.kt  |  7 +++----
 .../inmo/micro_utils/fsm/common/dsl/FSMBuilder.kt | 14 ++++++++------
 4 files changed, 27 insertions(+), 12 deletions(-)
 rename fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/{StateHandlerHolder.kt => StatesHandlerHolder.kt} (71%)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 261fbce2879..7c19c45fe22 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,9 @@
     * `Ktor`: `1.6.4` -> `1.6.5`
 * `Common`:
     * Type `Either` got its own serializer
+* `FSM`:
+    * `Common`:
+        * Add opportunity for comfortable adding default state handler
 
 ## 0.7.4
 
diff --git a/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/StateHandlerHolder.kt b/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/StatesHandlerHolder.kt
similarity index 71%
rename from fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/StateHandlerHolder.kt
rename to fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/StatesHandlerHolder.kt
index a92f9b96602..b849ba8462d 100644
--- a/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/StateHandlerHolder.kt
+++ b/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/StatesHandlerHolder.kt
@@ -6,7 +6,7 @@ import kotlin.reflect.KClass
  * Default realization of [StatesHandler]. It will incapsulate checking of [State] type in [checkHandleable] and class
  * casting in [handleState]
  */
-class StateHandlerHolder<I : State>(
+class StatesHandlerHolder<I : State>(
     private val inputKlass: KClass<I>,
     private val strict: Boolean = false,
     private val delegateTo: StatesHandler<I>
@@ -19,9 +19,20 @@ class StateHandlerHolder<I : State>(
 
     /**
      * Calls [delegateTo] method [StatesHandler.handleState] with [state] casted to [I]. Use [checkHandleable]
-     * to be sure that this [StateHandlerHolder] will be able to handle [state]
+     * to be sure that this [StatesHandlerHolder] will be able to handle [state]
      */
     override suspend fun StatesMachine.handleState(state: State): State? {
         return delegateTo.run { handleState(state as I) }
     }
 }
+
+@Deprecated("Renamed", ReplaceWith("StatesHandlerHolder"))
+typealias StateHandlerHolder<T> = StatesHandlerHolder<T>
+
+inline fun <reified T : State> StatesHandler<T>.holder(
+    strict: Boolean = true
+) = StatesHandlerHolder(
+    T::class,
+    strict,
+    this
+)
diff --git a/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/StatesMachine.kt b/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/StatesMachine.kt
index 11170c5b030..3dc9ef89cfa 100644
--- a/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/StatesMachine.kt
+++ b/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/StatesMachine.kt
@@ -2,11 +2,10 @@ package dev.inmo.micro_utils.fsm.common
 
 import dev.inmo.micro_utils.coroutines.*
 import kotlinx.coroutines.*
-import kotlinx.coroutines.flow.asFlow
 
 private suspend fun <I : State> StatesMachine.launchStateHandling(
     state: State,
-    handlers: List<StateHandlerHolder<out I>>
+    handlers: List<StatesHandlerHolder<out I>>
 ): State? {
     return handlers.firstOrNull { it.checkHandleable(state) } ?.run {
         handleState(state)
@@ -35,7 +34,7 @@ interface StatesMachine : StatesHandler<State> {
          */
         operator fun invoke(
             statesManager: StatesManager,
-            handlers: List<StateHandlerHolder<*>>
+            handlers: List<StatesHandlerHolder<*>>
         ) = DefaultStatesMachine(statesManager, handlers)
     }
 }
@@ -46,7 +45,7 @@ interface StatesMachine : StatesHandler<State> {
  */
 class DefaultStatesMachine (
     private val statesManager: StatesManager,
-    private val handlers: List<StateHandlerHolder<*>>
+    private val handlers: List<StatesHandlerHolder<*>>
 ) : StatesMachine {
     /**
      * Will call [launchStateHandling] for state handling
diff --git a/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/dsl/FSMBuilder.kt b/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/dsl/FSMBuilder.kt
index a5fd74a5ddb..11d39ec0752 100644
--- a/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/dsl/FSMBuilder.kt
+++ b/fsm/common/src/commonMain/kotlin/dev/inmo/micro_utils/fsm/common/dsl/FSMBuilder.kt
@@ -2,25 +2,27 @@ package dev.inmo.micro_utils.fsm.common.dsl
 
 import dev.inmo.micro_utils.fsm.common.*
 import dev.inmo.micro_utils.fsm.common.managers.*
-import dev.inmo.micro_utils.fsm.common.managers.InMemoryStatesManager
 import kotlin.reflect.KClass
 
 class FSMBuilder(
-    var statesManager: StatesManager = DefaultStatesManager(InMemoryDefaultStatesManagerRepo())
+    var statesManager: StatesManager = DefaultStatesManager(InMemoryDefaultStatesManagerRepo()),
+    var defaultStateHandler: StatesHandler<State>? = StatesHandler { null }
 ) {
-    private var states = mutableListOf<StateHandlerHolder<*>>()
+    private var states = mutableListOf<StatesHandlerHolder<*>>()
 
     fun <I : State> add(kClass: KClass<I>, handler: StatesHandler<I>) {
-        states.add(StateHandlerHolder(kClass, false, handler))
+        states.add(StatesHandlerHolder(kClass, false, handler))
     }
 
     fun <I : State> addStrict(kClass: KClass<I>, handler: StatesHandler<I>) {
-        states.add(StateHandlerHolder(kClass, true, handler))
+        states.add(StatesHandlerHolder(kClass, true, handler))
     }
 
     fun build() = StatesMachine(
         statesManager,
-        states.toList()
+        states.toList().let { list ->
+            defaultStateHandler ?.let { list + it.holder(false) } ?: list
+        }
     )
 }