home work RxJava, and fix comment

app/build.gradle

@@ -46,4 +46,5 @@ dependencies {
     implementation 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.7.0'
     implementation "io.reactivex.rxjava2:rxjava:2.2.21"
     implementation 'io.reactivex.rxjava2:rxandroid:2.1.1'
+    implementation 'com.squareup.retrofit2:adapter-rxjava2:2.3.0'
 }

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

@@ -1,55 +1,60 @@
 package otus.homework.reactivecats
 
-import android.content.Context
+import android.annotation.SuppressLint
 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.android.schedulers.AndroidSchedulers
+import io.reactivex.disposables.CompositeDisposable
+import io.reactivex.schedulers.Schedulers
+import java.util.concurrent.TimeUnit
 
+@SuppressLint("CheckResult")
 class CatsViewModel(
-    catsService: CatsService,
-    localCatFactsGenerator: LocalCatFactsGenerator,
-    context: Context
+    private val catsService: CatsService,
+    private val localCatFactsGenerator: LocalCatFactsGenerator,
 ) : ViewModel() {
-
+    private val subscriptionDisposables: 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
-                        )
-                    )
-                }
-            }
+        getFacts()
+    }
 
-            override fun onFailure(call: Call<Fact>, t: Throwable) {
-                _catsLiveData.value = ServerError
-            }
-        })
+    fun getFacts() {
+        val dispos = catsService.getCatFact()
+            .delay(2000, TimeUnit.MILLISECONDS)
+            .repeat()
+            .subscribeOn(Schedulers.io())
+            .observeOn(AndroidSchedulers.mainThread())
+            .subscribe(
+                { fact ->
+                    _catsLiveData.value = Success(fact)
+                }, {
+                    _catsLiveData.value =
+                        Success(localCatFactsGenerator.generateCatFact().blockingGet())
+                }
+            )
+        subscriptionDisposables.add(dispos)
     }
 
-    fun getFacts() {}
+    override fun onCleared() {
+        super.onCleared()
+        subscriptionDisposables.clear()
+    }
 }
 
 class CatsViewModelFactory(
     private val catsRepository: CatsService,
     private val localCatFactsGenerator: LocalCatFactsGenerator,
-    private val context: Context
-) :
+
+    ) :
     ViewModelProvider.NewInstanceFactory() {
 
     override fun <T : ViewModel> create(modelClass: Class<T>): T =
-        CatsViewModel(catsRepository, localCatFactsGenerator, context) as T
+        CatsViewModel(catsRepository, localCatFactsGenerator) as T
 }
 
 sealed class Result

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

@@ -1,7 +1,8 @@
 package otus.homework.reactivecats
 
-import android.content.Context
+import android.content.res.Resources
 import retrofit2.Retrofit
+import retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory
 import retrofit2.converter.gson.GsonConverterFactory
 
 class DiContainer {
@@ -10,10 +11,11 @@ class DiContainer {
         Retrofit.Builder()
             .baseUrl("https://cat-fact.herokuapp.com/facts/")
             .addConverterFactory(GsonConverterFactory.create())
+            .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
             .build()
     }
 
     val service by lazy { retrofit.create(CatsService::class.java) }
 
-    fun localCatFactsGenerator(context: Context) = LocalCatFactsGenerator(context)
+    fun localCatFactsGenerator(resources: Resources) = LocalCatFactsGenerator(resources)
 }

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

@@ -1,12 +1,14 @@
 package otus.homework.reactivecats
 
-import android.content.Context
+import android.content.res.Resources
 import io.reactivex.Flowable
 import io.reactivex.Single
+import java.util.concurrent.TimeUnit
 import kotlin.random.Random
 
+
 class LocalCatFactsGenerator(
-    private val context: Context
+    private val resources: Resources
 ) {
 
     /**
@@ -15,7 +17,9 @@ class LocalCatFactsGenerator(
      * обернутую в подходящий стрим(Flowable/Single/Observable и т.п)
      */
     fun generateCatFact(): Single<Fact> {
-        return Single.never()
+        return Single.just(
+            Fact(resources.getStringArray(R.array.local_cat_facts)[Random.nextInt(5)])
+        )
     }
 
     /**
@@ -24,7 +28,14 @@ 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()
+        var localFacts = ""
+        return Flowable.interval(2000, TimeUnit.MILLISECONDS).map {
+            localFacts = generateCatFactTest()
+            Fact(localFacts)
+        }
+            .distinctUntilChanged()
     }
+
+    private fun generateCatFactTest() =
+        resources.getStringArray(R.array.local_cat_facts)[Random.nextInt(5)]
 }

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() {
@@ -13,21 +12,22 @@ class MainActivity : AppCompatActivity() {
     private val catsViewModel by viewModels<CatsViewModel> {
         CatsViewModelFactory(
             diContainer.service,
-            diContainer.localCatFactsGenerator(applicationContext),
-            applicationContext
+            diContainer.localCatFactsGenerator(applicationContext.resources)
         )
     }
 
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         val view = layoutInflater.inflate(R.layout.activity_main, null) as CatsView
         setContentView(view)
-        catsViewModel.catsLiveData.observe(this) { result ->
-            when (result) {
-                is Success -> view.populate(result.fact)
-                is Error -> Toast.makeText(this, result.message, Toast.LENGTH_LONG).show()
-                ServerError -> Snackbar.make(view, "Network error", 1000).show()
+        catsViewModel.catsLiveData
+            .observe(this) { result ->
+                when (result) {
+                    is Success -> view.populate(result.fact)
+                    is Error -> Toast.makeText(this, result.message, Toast.LENGTH_LONG).show()
+                    ServerError -> Snackbar.make(view, "Network error", 1000).show()
+                }
             }
-        }
     }
 }