Added Deezer for loading Artist images

app/src/main/java/code/name/monkey/retromusic/deezer/DeezerApiService.kt

@@ -0,0 +1,63 @@
+package code.name.monkey.retromusic.deezer
+
+import android.content.Context
+import okhttp3.Cache
+import okhttp3.Interceptor
+import okhttp3.OkHttpClient
+import retrofit2.Call
+import retrofit2.Retrofit
+import retrofit2.converter.gson.GsonConverterFactory
+import retrofit2.create
+import retrofit2.http.GET
+import retrofit2.http.Query
+import java.io.File
+import java.util.*
+
+private const val BASE_QUERY_ARTIST = "search/artist"
+private const val BASE_URL = "https://api.deezer.com/"
+
+interface DeezerApiService {
+
+    @GET("$BASE_QUERY_ARTIST&limit=1")
+    fun getArtistImage(
+            @Query("q") artistName: String
+    ): Call<DeezerResponse>
+
+    companion object {
+        operator fun invoke(client: okhttp3.Call.Factory): DeezerApiService {
+            return Retrofit.Builder()
+                    .baseUrl(BASE_URL)
+                    .callFactory(client)
+                    .addConverterFactory(GsonConverterFactory.create())
+                    .build()
+                    .create()
+        }
+
+        fun createDefaultOkHttpClient(context: Context): OkHttpClient.Builder =
+                OkHttpClient.Builder()
+                        .cache(createDefaultCache(context))
+                        .addInterceptor(createCacheControlInterceptor())
+
+        private fun createDefaultCache(context: Context): Cache? {
+            val cacheDir = File(context.applicationContext.cacheDir.absolutePath, "/okhttp-deezer/")
+            if (cacheDir.mkdir() or cacheDir.isDirectory) {
+                return Cache(cacheDir, 1024 * 1024 * 10)
+            }
+            return null
+        }
+
+        private fun createCacheControlInterceptor(): Interceptor {
+            return Interceptor { chain ->
+                val modifiedRequest = chain.request().newBuilder()
+                        .addHeader("Cache-Control",
+                                String.format(
+                                        Locale.getDefault(),
+                                        "max-age=%d, max-stale=%d",
+                                        31536000, 31536000
+                                )
+                        ).build()
+                chain.proceed(modifiedRequest)
+            }
+        }
+    }
+}

app/src/main/java/code/name/monkey/retromusic/deezer/DeezerResponse.kt

@@ -0,0 +1,31 @@
+package code.name.monkey.retromusic.deezer
+
+import com.google.gson.annotations.SerializedName
+
+data class Data(
+        val id: String,
+        val link: String,
+        val name: String,
+        @SerializedName("nb_album")
+        val nbAlbum: Int,
+        @SerializedName("nb_fan")
+        val nbFan: Int,
+        val picture: String,
+        @SerializedName("picture_big")
+        val pictureBig: String,
+        @SerializedName("picture_medium")
+        val pictureMedium: String,
+        @SerializedName("picture_small")
+        val pictureSmall: String,
+        @SerializedName("picture_xl")
+        val pictureXl: String,
+        val radio: Boolean,
+        val tracklist: String,
+        val type: String
+)
+
+data class DeezerResponse(
+        val data: List<Data>,
+        val next: String,
+        val total: Int
+)