add lazy loadable bot info

tgbotapi.behaviour_builder/src/commonMain/kotlin/dev/inmo/tgbotapi/extensions/behaviour_builder/BehaviourBuilders.kt

@@ -3,6 +3,7 @@ package dev.inmo.tgbotapi.extensions.behaviour_builder
 import dev.inmo.micro_utils.coroutines.ContextSafelyExceptionHandler
 import dev.inmo.micro_utils.coroutines.ExceptionHandler
 import dev.inmo.tgbotapi.bot.TelegramBot
+import dev.inmo.tgbotapi.extensions.behaviour_builder.utils.DefaultCustomBehaviourContextAndTypeReceiver
 import dev.inmo.tgbotapi.extensions.utils.updates.retrieving.longPolling
 import dev.inmo.tgbotapi.extensions.utils.updates.retrieving.startGettingOfUpdatesByLongPolling
 import dev.inmo.tgbotapi.extensions.utils.updates.retrieving.updateHandlerWithMediaGroupsAdaptation
@@ -31,6 +32,7 @@ suspend fun TelegramBot.buildBehaviour(
     scope: CoroutineScope = defaultCoroutineScopeProvider(),
     defaultExceptionsHandler: ExceptionHandler<Unit>? = null,
     subcontextInitialAction: CustomBehaviourContextAndTypeReceiver<BehaviourContext, Unit, Update> = {},
+    useDefaultSubcontextInitialAction: Boolean = true,
     block: BehaviourContextReceiver<Unit>
 ): BehaviourContext = BehaviourContext(
     bot = this,
@@ -42,7 +44,11 @@ suspend fun TelegramBot.buildBehaviour(
         }
     },
     flowsUpdatesFilter = flowUpdatesFilter,
-    subcontextInitialAction = subcontextInitialAction
+    subcontextInitialAction = if (useDefaultSubcontextInitialAction) {
+        DefaultCustomBehaviourContextAndTypeReceiver(subcontextInitialAction)
+    } else {
+        subcontextInitialAction
+    }
 ).apply {
     block()
 }
@@ -67,12 +73,14 @@ suspend fun TelegramBot.buildBehaviourWithLongPolling(
     autoSkipTimeoutExceptions: Boolean = true,
     mediaGroupsDebounceTimeMillis: Long? = 1000L,
     subcontextInitialAction: CustomBehaviourContextAndTypeReceiver<BehaviourContext, Unit, Update> = {},
+    useDefaultSubcontextInitialAction: Boolean = true,
     block: BehaviourContextReceiver<Unit>
 ): Job {
     val behaviourContext = buildBehaviour(
         scope = scope,
         defaultExceptionsHandler = defaultExceptionsHandler,
         subcontextInitialAction = subcontextInitialAction,
+        useDefaultSubcontextInitialAction = useDefaultSubcontextInitialAction,
         block = block
     )
     return longPolling(

tgbotapi.behaviour_builder/src/commonMain/kotlin/dev/inmo/tgbotapi/extensions/behaviour_builder/BehaviourContext.kt

@@ -6,6 +6,7 @@ import dev.inmo.kslog.common.KSLog
 import dev.inmo.micro_utils.coroutines.*
 import dev.inmo.tgbotapi.bot.TelegramBot
 import dev.inmo.tgbotapi.extensions.behaviour_builder.utils.handlers_registrar.TriggersHolder
+import dev.inmo.tgbotapi.extensions.behaviour_builder.utils.optionallyWithDefaultReceiver
 import dev.inmo.tgbotapi.types.UpdateId
 import dev.inmo.tgbotapi.types.update.abstracts.Update
 import dev.inmo.tgbotapi.updateshandlers.*
@@ -24,6 +25,7 @@ typealias CustomBehaviourContextAndTwoTypesReceiver<BC, T, I1, I2> = suspend BC.
 typealias BehaviourContextAndTwoTypesReceiver<T, I1, I2> = CustomBehaviourContextAndTwoTypesReceiver<BehaviourContext, T, I1, I2>
 inline fun <T> BehaviourContextReceiver(noinline block: BehaviourContextReceiver<T>) = block
 inline fun <BC, T> CustomBehaviourContextReceiver(noinline block: CustomBehaviourContextReceiver<BC, T>) = block
+inline fun <BC, T, I> CustomBehaviourContextAndTypeReceiver(noinline block: CustomBehaviourContextAndTypeReceiver<BC, T, I>) = block
 inline fun <T, I> BehaviourContextAndTypeReceiver(noinline block: BehaviourContextAndTypeReceiver<T, I>) = block
 inline fun <T, I1, I2> BehaviourContextAndTwoTypesReceiver(noinline block: BehaviourContextAndTwoTypesReceiver<T, I1, I2>) = block
 internal inline fun <BC, T, I1, I2> CustomBehaviourContextAndTwoTypesReceiver<BC, T, I1, I2>.toOneType(
@@ -134,8 +136,15 @@ fun BehaviourContext(
     scope: CoroutineScope,
     flowsUpdatesFilter: FlowsUpdatesFilter = FlowsUpdatesFilter(),
     triggersHolder: TriggersHolder = TriggersHolder(),
+    useDefaultSubcontextInitialAction: Boolean = true,
     subcontextInitialAction: CustomBehaviourContextAndTypeReceiver<BehaviourContext, Unit, Update> = {}
-) = DefaultBehaviourContext(bot, scope, upstreamUpdatesFlow = flowsUpdatesFilter.allUpdatesFlow, triggersHolder = triggersHolder, subcontextInitialAction = subcontextInitialAction)
+) = DefaultBehaviourContext(
+    bot = bot,
+    scope = scope,
+    upstreamUpdatesFlow = flowsUpdatesFilter.allUpdatesFlow,
+    triggersHolder = triggersHolder,
+    subcontextInitialAction = subcontextInitialAction.optionallyWithDefaultReceiver(useDefaultSubcontextInitialAction)
+)
 
 inline fun <T> BehaviourContext(
     bot: TelegramBot,
@@ -143,8 +152,15 @@ inline fun <T> BehaviourContext(
     flowsUpdatesFilter: FlowsUpdatesFilter = FlowsUpdatesFilter(),
     triggersHolder: TriggersHolder = TriggersHolder(),
     noinline subcontextInitialAction: CustomBehaviourContextAndTypeReceiver<BehaviourContext, Unit, Update> = {},
+    useDefaultSubcontextInitialAction: Boolean = true,
     crossinline block: BehaviourContext.() -> T
-) = DefaultBehaviourContext(bot, scope, upstreamUpdatesFlow = flowsUpdatesFilter.allUpdatesFlow, triggersHolder = triggersHolder, subcontextInitialAction = subcontextInitialAction).run(block)
+) = DefaultBehaviourContext(
+    bot = bot,
+    scope = scope,
+    upstreamUpdatesFlow = flowsUpdatesFilter.allUpdatesFlow,
+    triggersHolder = triggersHolder,
+    subcontextInitialAction = subcontextInitialAction.optionallyWithDefaultReceiver(useDefaultSubcontextInitialAction)
+).run(block)
 
 /**
  * Creates new [BehaviourContext] using its [BehaviourContext.copy] method

tgbotapi.behaviour_builder/src/commonMain/kotlin/dev/inmo/tgbotapi/extensions/behaviour_builder/TelegramBot.kt

@@ -39,6 +39,7 @@ suspend fun telegramBotWithBehaviour(
     testServer: Boolean = false,
     subcontextInitialAction: CustomBehaviourContextAndTypeReceiver<BehaviourContext, Unit, Update> = {},
     fileLinkUrlMapper: TelegramAPIUrlsKeeper.(String) -> String = { "${fileBaseUrl}/$it" },
+    useDefaultSubcontextInitialAction: Boolean = true,
     block: BehaviourContextReceiver<Unit>
 ): TelegramBot = telegramBot(
     token,
@@ -52,6 +53,7 @@ suspend fun telegramBotWithBehaviour(
         scope = scope ?: CoroutineScope(coroutineContext),
         defaultExceptionsHandler = defaultExceptionsHandler,
         subcontextInitialAction = subcontextInitialAction,
+        useDefaultSubcontextInitialAction = useDefaultSubcontextInitialAction,
         block = block
     )
 }
@@ -86,6 +88,7 @@ suspend fun telegramBotWithBehaviourAndLongPolling(
     mediaGroupsDebounceTimeMillis: Long? = 1000L,
     subcontextInitialAction: CustomBehaviourContextAndTypeReceiver<BehaviourContext, Unit, Update> = {},
     fileLinkUrlMapper: TelegramAPIUrlsKeeper.(String) -> String = { "${fileBaseUrl}/$it" },
+    useDefaultSubcontextInitialAction: Boolean = true,
     block: BehaviourContextReceiver<Unit>
 ): Pair<TelegramBot, Job> {
     return telegramBot(
@@ -103,6 +106,7 @@ suspend fun telegramBotWithBehaviourAndLongPolling(
             autoSkipTimeoutExceptions = autoSkipTimeoutExceptions,
             mediaGroupsDebounceTimeMillis = mediaGroupsDebounceTimeMillis,
             subcontextInitialAction = subcontextInitialAction,
+            useDefaultSubcontextInitialAction = useDefaultSubcontextInitialAction,
             block = block
         )
     }

tgbotapi.behaviour_builder/src/commonMain/kotlin/dev/inmo/tgbotapi/extensions/behaviour_builder/utils/DefaultCustomBehaviourContextAndTypeReceiver.kt

@@ -0,0 +1,102 @@
+package dev.inmo.tgbotapi.extensions.behaviour_builder.utils
+
+import dev.inmo.micro_utils.common.Warning
+import dev.inmo.tgbotapi.extensions.behaviour_builder.BehaviourContext
+import dev.inmo.tgbotapi.extensions.behaviour_builder.CustomBehaviourContextAndTypeReceiver
+import dev.inmo.tgbotapi.extensions.behaviour_builder.utils.DefaultCustomBehaviourContextAndTypeReceiver.Companion.BOT_INFO_RECEIVER
+import dev.inmo.tgbotapi.requests.bot.GetMe
+import dev.inmo.tgbotapi.types.chat.ExtendedBot
+import dev.inmo.tgbotapi.types.update.abstracts.Update
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+
+/**
+ * Returns bot information (result of [GetMe]) associated with this [BehaviourContext], if available.
+ *
+ * The value is lazily computed and cached by [DefaultCustomBehaviourContextAndTypeReceiver] when it is used
+ * to wrap behaviour handlers. If this context was not prepared by that wrapper, the function returns null.
+ *
+ * Thread-safety:
+ * - The underlying retrieval is protected by a mutex to ensure the info is fetched at most once per context.
+ *
+ * @return [ExtendedBot] with bot details, or null if no bot info provider is registered in this context.
+ */
+suspend fun BehaviourContext.botInfo(): ExtendedBot? {
+    return (data[BOT_INFO_RECEIVER] as? DefaultCustomBehaviourContextAndTypeReceiver.IReceiver) ?.run {
+        invoke()
+    }
+}
+
+@Warning("It is internal API and can be changed without notes")
+fun <BC : BehaviourContext, R, U : Update> CustomBehaviourContextAndTypeReceiver<BC, R, U>.withDefaultReceiver() = DefaultCustomBehaviourContextAndTypeReceiver(this)
+@Warning("It is internal API and can be changed without notes")
+fun <BC : BehaviourContext, R, U : Update> CustomBehaviourContextAndTypeReceiver<BC, R, U>.optionallyWithDefaultReceiver(
+    include: Boolean
+) = if (include) {
+    withDefaultReceiver()
+} else {
+    this
+}
+
+/**
+ * Behaviour wrapper that injects a lazily-evaluated, cached provider of bot information into the [BehaviourContext].
+ *
+ * When this wrapper is used, any code executed inside it may call [BehaviourContext.botInfo] to obtain
+ * the current bot's [ExtendedBot] information. The info is fetched via [GetMe] only once and then cached
+ * for subsequent calls, with concurrent access synchronized by a mutex.
+ *
+ * @param BC Type of [BehaviourContext] used in the wrapped logic.
+ * @param R Result type produced by the wrapped receiver.
+ * @param U Type of [Update] handled by the wrapped receiver.
+ * @param wrapperReceiver The original receiver to be invoked after the bot info provider is registered in the context.
+ */
+class DefaultCustomBehaviourContextAndTypeReceiver<BC : BehaviourContext, R, U : Update>(
+    private val wrapperReceiver: CustomBehaviourContextAndTypeReceiver<BC, R, U>
+) : CustomBehaviourContextAndTypeReceiver<BC, R, U> {
+    private var botInfo: ExtendedBot? = null
+    private val mutex = Mutex()
+
+    /**
+     * Lightweight provider of bot information bound to a [BehaviourContext].
+     *
+     * Implementations must return the current [ExtendedBot] instance, computing it if necessary.
+     */
+    fun interface IReceiver {
+        /**
+         * Get or compute the bot information for the current [BehaviourContext].
+         *
+         * Implementations may cache the value and are free to apply synchronization as needed.
+         */
+        suspend fun BehaviourContext.invoke(): ExtendedBot
+    }
+
+    /**
+     * Internal provider that performs a single, thread-safe retrieval of bot info via [GetMe] and caches it.
+     */
+    private val internalReceiver: IReceiver = IReceiver {
+        botInfo ?: mutex.withLock {
+            botInfo ?: execute(GetMe).also {
+                botInfo = it
+            }
+        }
+    }
+
+    /**
+     * Registers the internal bot info provider in [BehaviourContext.data] and then delegates to [wrapperReceiver].
+     *
+     * The provider is stored under [BOT_INFO_RECEIVER] key, enabling calls to [BehaviourContext.botInfo] within
+     * the wrapped behaviour.
+     */
+    override suspend fun invoke(p1: BC, p2: U): R {
+        p1.data[BOT_INFO_RECEIVER] = internalReceiver
+
+        return wrapperReceiver(p1, p2)
+    }
+
+    companion object {
+        /**
+         * Key used to store the bot info provider inside [BehaviourContext.data].
+         */
+        const val BOT_INFO_RECEIVER = "ktgbotapi_bot_info_receiver"
+    }
+}