add support of data checking in webapp

WebApp/src/jsMain/kotlin/main.kt

@@ -2,10 +2,8 @@ import dev.inmo.micro_utils.coroutines.launchSafelyWithoutExceptions
 import dev.inmo.tgbotapi.types.webAppQueryIdField
 import dev.inmo.tgbotapi.webapps.*
 import io.ktor.client.HttpClient
-import io.ktor.client.call.receive
 import io.ktor.client.request.*
-import io.ktor.client.statement.HttpResponse
-import io.ktor.client.statement.readText
+import io.ktor.client.statement.bodyAsText
 import io.ktor.http.*
 import io.ktor.http.content.TextContent
 import kotlinx.browser.document
@@ -13,6 +11,7 @@ import kotlinx.browser.window
 import kotlinx.coroutines.*
 import kotlinx.dom.appendElement
 import kotlinx.dom.appendText
+import kotlinx.serialization.json.Json
 import org.w3c.dom.HTMLElement
 
 fun HTMLElement.log(text: String) {
@@ -22,14 +21,38 @@ fun HTMLElement.log(text: String) {
 
 fun main() {
     console.log("Web app started")
+    val client = HttpClient()
+    val baseUrl = window.location.origin.removeSuffix("/")
+
     window.onload = {
         val scope = CoroutineScope(Dispatchers.Default)
         runCatching {
+
+            scope.launchSafelyWithoutExceptions {
+                val response = client.post("$baseUrl/check") {
+                    setBody(
+                        Json { }.encodeToString(
+                            WebAppDataWrapper.serializer(),
+                            WebAppDataWrapper(webApp.initData, webApp.initDataUnsafe.hash)
+                        )
+                    )
+                }
+                val dataIsSafe = response.bodyAsText().toBoolean()
+
+                document.body ?.appendElement("div") {
+                    textContent = if (dataIsSafe) {
+                        "Data is safe"
+                    } else {
+                        "Data is unsafe"
+                    }
+                }
+            }
+
             document.body ?.appendElement("button") {
                 addEventListener("click", {
                     scope.launchSafelyWithoutExceptions {
                         handleResult({ "Clicked" }) {
-                            HttpClient().post("${window.location.origin.removeSuffix("/")}/inline") {
+                            client.post("${window.location.origin.removeSuffix("/")}/inline") {
                                 parameter(webAppQueryIdField, it)
                                 setBody(TextContent("Clicked", ContentType.Text.Plain))
                                 document.body ?.log(url.build().toString())