Задание 1. Перейти с коллбеков на саспенд функции и корутины

app/build.gradle

@@ -42,4 +42,5 @@ dependencies {
     implementation 'com.google.android.material:material:1.3.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
     implementation 'com.squareup.picasso:picasso:2.71828'
+    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.6.4'
 }

app/src/main/java/otus/homework/coroutines/CatsPresenter.kt

@@ -1,28 +1,29 @@
 package otus.homework.coroutines
 
-import retrofit2.Call
-import retrofit2.Callback
-import retrofit2.Response
+import kotlinx.coroutines.*
+import java.net.SocketTimeoutException
 
 class CatsPresenter(
     private val catsService: CatsService
 ) {
 
     private var _catsView: ICatsView? = null
+    private val outerScope = PresenterScope()
+    private lateinit var innerScope: CoroutineScope
 
     fun onInitComplete() {
-        catsService.getCatFact().enqueue(object : Callback<Fact> {
-
-            override fun onResponse(call: Call<Fact>, response: Response<Fact>) {
-                if (response.isSuccessful && response.body() != null) {
-                    _catsView?.populate(response.body()!!)
-                }
-            }
-
-            override fun onFailure(call: Call<Fact>, t: Throwable) {
-                CrashMonitor.trackWarning()
+        outerScope.launch {
+            innerScope = CoroutineScope(Dispatchers.IO)
+            try {
+                val catFact = innerScope.async { catsService.getCatFact() }
+                _catsView?.populate(catFact.await())
+            } catch (exc: SocketTimeoutException) {
+                _catsView?.makeToast("Не удалось получить ответ от сервером")
+            } catch (exc: Exception) {
+                CrashMonitor.trackWarning(exc)
+                _catsView?.makeToast(exc.message.toString())
             }
-        })
+        }
     }
 
     fun attachView(catsView: ICatsView) {
@@ -31,5 +32,7 @@ class CatsPresenter(
 
     fun detachView() {
         _catsView = null
+        outerScope.cancel()
+        innerScope.cancel()
     }
 }

app/src/main/java/otus/homework/coroutines/CatsService.kt

@@ -1,10 +1,9 @@
 package otus.homework.coroutines
 
-import retrofit2.Call
 import retrofit2.http.GET
 
 interface CatsService {
 
     @GET("fact")
-    fun getCatFact() : Call<Fact>
+    suspend fun getCatFact(): Fact
 }

app/src/main/java/otus/homework/coroutines/CatsView.kt

@@ -4,6 +4,7 @@ import android.content.Context
 import android.util.AttributeSet
 import android.widget.Button
 import android.widget.TextView
+import android.widget.Toast
 import androidx.constraintlayout.widget.ConstraintLayout
 
 class CatsView @JvmOverloads constructor(
@@ -22,11 +23,17 @@ class CatsView @JvmOverloads constructor(
     }
 
     override fun populate(fact: Fact) {
-        findViewById<TextView>(R.id.fact_textView).text = fact.text
+        findViewById<TextView>(R.id.fact_textView).text = fact.fact
+    }
+
+    override fun makeToast(text: String) {
+        Toast.makeText(context, text, Toast.LENGTH_LONG).show()
     }
 }
 
 interface ICatsView {
 
     fun populate(fact: Fact)
+
+    fun makeToast(text: String)
 }

app/src/main/java/otus/homework/coroutines/CrashMonitor.kt

@@ -5,6 +5,6 @@ object CrashMonitor {
     /**
      * Pretend this is Crashlytics/AppCenter
      */
-    fun trackWarning() {
+    fun trackWarning(e: Throwable) {
     }
 }

app/src/main/java/otus/homework/coroutines/Fact.kt

@@ -3,22 +3,8 @@ package otus.homework.coroutines
 import com.google.gson.annotations.SerializedName
 
 data class Fact(
-	@field:SerializedName("createdAt")
-	val createdAt: String,
-	@field:SerializedName("deleted")
-	val deleted: Boolean,
-	@field:SerializedName("_id")
-	val id: String,
-	@field:SerializedName("text")
-	val text: String,
-	@field:SerializedName("source")
-	val source: String,
-	@field:SerializedName("used")
-	val used: Boolean,
-	@field:SerializedName("type")
-	val type: String,
-	@field:SerializedName("user")
-	val user: String,
-	@field:SerializedName("updatedAt")
-	val updatedAt: String
+	@field:SerializedName("fact")
+	val fact: String,
+	@field:SerializedName("length")
+	val length: Int
 )

app/src/main/java/otus/homework/coroutines/PresenterScope.kt

@@ -0,0 +1,12 @@
+package otus.homework.coroutines
+
+import kotlinx.coroutines.CoroutineName
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlin.coroutines.CoroutineContext
+
+class PresenterScope: CoroutineScope {
+
+    override val coroutineContext: CoroutineContext
+        get() = Dispatchers.Main + CoroutineName("CatsCoroutine")
+}