Hw reactive cats kuzmin

app/build.gradle

@@ -4,13 +4,13 @@ plugins {
 }
 
 android {
-    compileSdkVersion 30
+    compileSdkVersion 33
     buildToolsVersion "30.0.3"
 
     defaultConfig {
         applicationId "otus.homework.reactivecats"
         minSdkVersion 23
-        targetSdkVersion 30
+        targetSdkVersion 33
         versionCode 1
         versionName "1.0"
 
@@ -46,4 +46,5 @@ dependencies {
     implementation 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.3.1'
     implementation "io.reactivex.rxjava2:rxjava:2.2.21"
     implementation 'io.reactivex.rxjava2:rxandroid:2.1.1'
+    implementation 'com.squareup.retrofit2:adapter-rxjava2:2.4.0'
 }

app/src/main/java/otus/homework/reactivecats/CatFactsCallable.kt

@@ -0,0 +1,21 @@
+package otus.homework.reactivecats
+
+import java.util.concurrent.Callable
+import kotlin.random.Random
+
+class CatFactsCallable(
+    private val catFacts: Array<String>
+    ) : Callable<Fact> {
+
+    private var previous: String? = null
+
+    override fun call(): Fact {
+        while (true) {
+            val fact = catFacts[Random.nextInt(5)]
+            return if (fact != previous) {
+                previous = fact
+                Fact(fact)
+            } else continue
+        }
+    }
+}

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

@@ -1,10 +1,10 @@
 package otus.homework.reactivecats
 
-import retrofit2.Call
+import io.reactivex.Single
 import retrofit2.http.GET
 
 interface CatsService {
 
     @GET("random?animal_type=cat")
-    fun getCatFact(): Call<Fact>
+    fun getCatFact(): Single<Fact>
 }

app/src/main/java/otus/homework/reactivecats/CatsViewModel.kt

@@ -5,40 +5,44 @@ import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.ViewModelProvider
-import retrofit2.Call
-import retrofit2.Callback
-import retrofit2.Response
+import io.reactivex.disposables.CompositeDisposable
+import io.reactivex.schedulers.Schedulers
+import java.util.concurrent.TimeUnit
 
 class CatsViewModel(
-    catsService: CatsService,
-    localCatFactsGenerator: LocalCatFactsGenerator,
-    context: Context
+    val catsService: CatsService,
+    val localCatFactsGenerator: LocalCatFactsGenerator,
+    val context: Context
 ) : ViewModel() {
 
+    private val compositeDisposable = CompositeDisposable()
+
     private val _catsLiveData = MutableLiveData<Result>()
     val catsLiveData: LiveData<Result> = _catsLiveData
 
     init {
-        catsService.getCatFact().enqueue(object : Callback<Fact> {
-            override fun onResponse(call: Call<Fact>, response: Response<Fact>) {
-                if (response.isSuccessful && response.body() != null) {
-                    _catsLiveData.value = Success(response.body()!!)
-                } else {
-                    _catsLiveData.value = Error(
-                        response.errorBody()?.string() ?: context.getString(
-                            R.string.default_error_text
-                        )
-                    )
-                }
-            }
-
-            override fun onFailure(call: Call<Fact>, t: Throwable) {
-                _catsLiveData.value = ServerError
-            }
-        })
+        getFacts()
+    }
+
+    fun getFacts() {
+        val disposable = catsService.getCatFact()
+            .subscribeOn(Schedulers.io())
+            .delay(2, TimeUnit.SECONDS)
+            .onErrorResumeNext(localCatFactsGenerator.generateCatFact())
+            .subscribe({
+                _catsLiveData.postValue(Success(it))
+            }, {
+                _catsLiveData.postValue(
+                    Error(it.message ?: context.getString(R.string.default_error_text)))
+            })
+
+        compositeDisposable.add(disposable)
     }
 
-    fun getFacts() {}
+    override fun onCleared() {
+        super.onCleared()
+        compositeDisposable.dispose()
+    }
 }
 
 class CatsViewModelFactory(

app/src/main/java/otus/homework/reactivecats/DiContainer.kt

@@ -2,6 +2,7 @@ package otus.homework.reactivecats
 
 import android.content.Context
 import retrofit2.Retrofit
+import retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory
 import retrofit2.converter.gson.GsonConverterFactory
 
 class DiContainer {
@@ -10,6 +11,7 @@ class DiContainer {
         Retrofit.Builder()
             .baseUrl("https://cat-fact.herokuapp.com/facts/")
             .addConverterFactory(GsonConverterFactory.create())
+            .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
             .build()
     }
 

app/src/main/java/otus/homework/reactivecats/LocalCatFactsGenerator.kt

@@ -3,6 +3,7 @@ package otus.homework.reactivecats
 import android.content.Context
 import io.reactivex.Flowable
 import io.reactivex.Single
+import java.util.concurrent.TimeUnit
 import kotlin.random.Random
 
 class LocalCatFactsGenerator(
@@ -15,7 +16,8 @@ class LocalCatFactsGenerator(
      * обернутую в подходящий стрим(Flowable/Single/Observable и т.п)
      */
     fun generateCatFact(): Single<Fact> {
-        return Single.never()
+        val catFacts = context.resources.getStringArray(R.array.local_cat_facts)
+        return Single.just(Fact(catFacts[Random.nextInt(5)]))
     }
 
     /**
@@ -24,7 +26,8 @@ class LocalCatFactsGenerator(
      * Если вновь заэмиченный Fact совпадает с предыдущим - пропускаем элемент.
      */
     fun generateCatFactPeriodically(): Flowable<Fact> {
-        val success = Fact(context.resources.getStringArray(R.array.local_cat_facts)[Random.nextInt(5)])
-        return Flowable.empty()
+        val catFacts = context.resources.getStringArray(R.array.local_cat_facts)
+        return Flowable.fromCallable(CatFactsCallable(catFacts))
+            .repeatWhen { it.delay(2, TimeUnit.SECONDS) }
     }
 }

app/src/main/java/otus/homework/reactivecats/MainActivity.kt

@@ -1,10 +1,9 @@
 package otus.homework.reactivecats
 
-import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
 import android.widget.Toast
 import androidx.activity.viewModels
-import androidx.lifecycle.lifecycleScope
+import androidx.appcompat.app.AppCompatActivity
 import com.google.android.material.snackbar.Snackbar
 
 class MainActivity : AppCompatActivity() {