From a3106ca93e55c53243c8310309a1c8ffc175f357 Mon Sep 17 00:00:00 2001
From: Kirill Ruban <krumsosh@gmail.com>
Date: Sun, 16 Feb 2025 13:53:09 +0300
Subject: [PATCH] Coroutines homework

---
 app/build.gradle                              |  2 +
 .../otus/homework/coroutines/CatsPresenter.kt | 35 ------------
 .../otus/homework/coroutines/CatsService.kt   |  8 ++-
 .../java/otus/homework/coroutines/CatsView.kt | 36 ++++++++++--
 .../otus/homework/coroutines/CatsViewModel.kt | 55 +++++++++++++++++++
 .../otus/homework/coroutines/DiContainer.kt   | 14 +++--
 .../otus/homework/coroutines/MainActivity.kt  | 25 +++++----
 app/src/main/res/layout/activity_main.xml     |  9 +++
 app/src/main/res/values/strings.xml           |  2 +
 9 files changed, 129 insertions(+), 57 deletions(-)
 delete mode 100644 app/src/main/java/otus/homework/coroutines/CatsPresenter.kt
 create mode 100644 app/src/main/java/otus/homework/coroutines/CatsViewModel.kt

diff --git a/app/build.gradle b/app/build.gradle
index a414e0e8..06a9e121 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -41,4 +41,6 @@ dependencies {
     implementation 'com.google.android.material:material:1.11.0'
     implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
     implementation 'com.squareup.picasso:picasso:2.71828'
+    implementation 'androidx.activity:activity-ktx:1.9.2'
+    implementation 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.8.6'
 }
\ No newline at end of file
diff --git a/app/src/main/java/otus/homework/coroutines/CatsPresenter.kt b/app/src/main/java/otus/homework/coroutines/CatsPresenter.kt
deleted file mode 100644
index e4b05120..00000000
--- a/app/src/main/java/otus/homework/coroutines/CatsPresenter.kt
+++ /dev/null
@@ -1,35 +0,0 @@
-package otus.homework.coroutines
-
-import retrofit2.Call
-import retrofit2.Callback
-import retrofit2.Response
-
-class CatsPresenter(
-    private val catsService: CatsService
-) {
-
-    private var _catsView: ICatsView? = null
-
-    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()
-            }
-        })
-    }
-
-    fun attachView(catsView: ICatsView) {
-        _catsView = catsView
-    }
-
-    fun detachView() {
-        _catsView = null
-    }
-}
\ No newline at end of file
diff --git a/app/src/main/java/otus/homework/coroutines/CatsService.kt b/app/src/main/java/otus/homework/coroutines/CatsService.kt
index 479b2cfb..774a9957 100644
--- a/app/src/main/java/otus/homework/coroutines/CatsService.kt
+++ b/app/src/main/java/otus/homework/coroutines/CatsService.kt
@@ -6,5 +6,11 @@ import retrofit2.http.GET
 interface CatsService {
 
     @GET("fact")
-    fun getCatFact() : Call<Fact>
+    suspend fun getCatFact() : Fact
+}
+
+interface CatsImageService {
+
+    @GET("search")
+    suspend fun getCatImage(): List<Image>
 }
\ No newline at end of file
diff --git a/app/src/main/java/otus/homework/coroutines/CatsView.kt b/app/src/main/java/otus/homework/coroutines/CatsView.kt
index be04b2a8..2e0a7980 100644
--- a/app/src/main/java/otus/homework/coroutines/CatsView.kt
+++ b/app/src/main/java/otus/homework/coroutines/CatsView.kt
@@ -1,10 +1,16 @@
 package otus.homework.coroutines
 
 import android.content.Context
+
 import android.util.AttributeSet
 import android.widget.Button
+import android.widget.ImageView
 import android.widget.TextView
+import android.widget.Toast
 import androidx.constraintlayout.widget.ConstraintLayout
+import com.google.gson.annotations.SerializedName
+import com.squareup.picasso.Picasso
+
 
 class CatsView @JvmOverloads constructor(
     context: Context,
@@ -12,21 +18,39 @@ class CatsView @JvmOverloads constructor(
     defStyleAttr: Int = 0
 ) : ConstraintLayout(context, attrs, defStyleAttr), ICatsView {
 
-    var presenter :CatsPresenter? = null
+    var catsViewModel: CatsViewModel? = null
 
     override fun onFinishInflate() {
         super.onFinishInflate()
         findViewById<Button>(R.id.button).setOnClickListener {
-            presenter?.onInitComplete()
+            catsViewModel?.getData()
         }
     }
 
-    override fun populate(fact: Fact) {
-        findViewById<TextView>(R.id.fact_textView).text = fact.fact
+    override fun populate(catsData: CatsData) {
+        findViewById<TextView>(R.id.fact_textView).text = catsData.fact
+        Picasso.get().load(catsData.image.url).into(findViewById<ImageView>(R.id.cat_imageView))
+    }
+
+    override fun showError(message: String) {
+        Toast.makeText(context, message, Toast.LENGTH_SHORT).show()
+
     }
 }
 
 interface ICatsView {
 
-    fun populate(fact: Fact)
-}
\ No newline at end of file
+    fun populate(catsData: CatsData)
+    fun showError(message: String)
+}
+
+
+data class Image(
+    @field:SerializedName("url")
+    val url: String
+)
+
+data class CatsData(
+    val fact: String,
+    val image: Image
+)
diff --git a/app/src/main/java/otus/homework/coroutines/CatsViewModel.kt b/app/src/main/java/otus/homework/coroutines/CatsViewModel.kt
new file mode 100644
index 00000000..f371fda8
--- /dev/null
+++ b/app/src/main/java/otus/homework/coroutines/CatsViewModel.kt
@@ -0,0 +1,55 @@
+package otus.homework.coroutines
+
+import android.app.Application
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
+import androidx.lifecycle.viewModelScope
+import kotlinx.coroutines.CoroutineExceptionHandler
+import kotlinx.coroutines.async
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.launch
+
+class CatsViewModel(
+    private val catsService: CatsService,
+    private val imageService: CatsImageService,
+    private val context: Application
+) : ViewModel() {
+    private val _catsLiveData = MutableLiveData<Result>()
+    val catsLiveData: LiveData<Result> = _catsLiveData
+
+    init {
+        getData()
+    }
+
+    fun getData() {
+        val handler = CoroutineExceptionHandler { _, throwable ->
+            CrashMonitor.trackWarning()
+            if (throwable is java.net.SocketTimeoutException) _catsLiveData.value =
+                Error(context.getString(R.string.socket_timeout_exception))
+            else _catsLiveData.value =
+                Error(throwable.message ?: context.getString(R.string.unknown_exception))
+        }
+        viewModelScope.launch(handler) {
+            coroutineScope {
+                val fact = async { catsService.getCatFact().fact }
+                val image = async { imageService.getCatImage().first() }
+                _catsLiveData.value = Success(CatsData(fact.await(), image.await()))
+            }
+        }
+    }
+}
+
+class CatsViewModelFactory(
+    private val catsService: CatsService,
+    private val imageService: CatsImageService,
+    private val context: Application
+) : ViewModelProvider.NewInstanceFactory() {
+    override fun <T : ViewModel> create(modelClass: Class<T>): T =
+        CatsViewModel(catsService, imageService, context) as T
+}
+
+sealed class Result
+data class Success(val data: CatsData) : Result()
+data class Error(val message: String) : Result()
\ No newline at end of file
diff --git a/app/src/main/java/otus/homework/coroutines/DiContainer.kt b/app/src/main/java/otus/homework/coroutines/DiContainer.kt
index 23ddc3b2..64fad4f9 100644
--- a/app/src/main/java/otus/homework/coroutines/DiContainer.kt
+++ b/app/src/main/java/otus/homework/coroutines/DiContainer.kt
@@ -5,12 +5,18 @@ import retrofit2.converter.gson.GsonConverterFactory
 
 class DiContainer {
 
-    private val retrofit by lazy {
+    private fun getRetrofit(url: String) =
         Retrofit.Builder()
-            .baseUrl("https://catfact.ninja/")
+            .baseUrl(url)
             .addConverterFactory(GsonConverterFactory.create())
             .build()
-    }
 
-    val service by lazy { retrofit.create(CatsService::class.java) }
+
+    val service: CatsService by lazy { getRetrofit(FACT_URL).create(CatsService::class.java) }
+    val imageService: CatsImageService by lazy { getRetrofit(IMAGE_URL).create(CatsImageService::class.java) }
+
+    companion object {
+        private const val FACT_URL = "https://catfact.ninja/"
+        private const val IMAGE_URL = "https://api.thecatapi.com/v1/images/"
+    }
 }
\ No newline at end of file
diff --git a/app/src/main/java/otus/homework/coroutines/MainActivity.kt b/app/src/main/java/otus/homework/coroutines/MainActivity.kt
index a9dafb3b..2b9e0e80 100644
--- a/app/src/main/java/otus/homework/coroutines/MainActivity.kt
+++ b/app/src/main/java/otus/homework/coroutines/MainActivity.kt
@@ -2,10 +2,17 @@ package otus.homework.coroutines
 
 import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
+import androidx.activity.viewModels
 
 class MainActivity : AppCompatActivity() {
 
-    lateinit var catsPresenter: CatsPresenter
+    private val catsViewModel by viewModels<CatsViewModel> {
+        CatsViewModelFactory(
+            diContainer.service,
+            diContainer.imageService,
+            application
+        )
+    }
 
     private val diContainer = DiContainer()
 
@@ -15,16 +22,12 @@ class MainActivity : AppCompatActivity() {
         val view = layoutInflater.inflate(R.layout.activity_main, null) as CatsView
         setContentView(view)
 
-        catsPresenter = CatsPresenter(diContainer.service)
-        view.presenter = catsPresenter
-        catsPresenter.attachView(view)
-        catsPresenter.onInitComplete()
-    }
-
-    override fun onStop() {
-        if (isFinishing) {
-            catsPresenter.detachView()
+        view.catsViewModel = catsViewModel
+        catsViewModel.catsLiveData.observe(this) {
+            when (it) {
+                is Error -> view.showError(it.message)
+                is Success -> view.populate(it.data)
+            }
         }
-        super.onStop()
     }
 }
\ No newline at end of file
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index 9508066d..e410c17e 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -7,6 +7,15 @@
     android:layout_height="match_parent"
     tools:context=".MainActivity">
 
+    <ImageView
+        android:id="@+id/cat_imageView"
+        android:layout_width="match_parent"
+        android:layout_height="200dp"
+        android:contentDescription="Cat's image"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent" />
+
     <TextView
         android:id="@+id/fact_textView"
         android:textColor="@color/black"
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 6c270d5d..11a7aec1 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -1,4 +1,6 @@
 <resources>
     <string name="app_name">Cat Facts </string>
     <string name="more_facts">More Facts</string>
+    <string name="socket_timeout_exception">socket timeout</string>
+    <string name="unknown_exception">unknown error</string>
 </resources>
\ No newline at end of file