condense platform-specific logic into one file per platform

- change retryIfInternalServerError to retryOnInternalServerErrorTimes to allow multiple times/infinite retry on internal server error
- remove redundant base64 code

Signed-off-by: Adam Ratzman <adam@adamratzman.com>

Author: adamint

src/androidMain/kotlin/com/adamratzman/spotify/SpotifyLogger.kt

@@ -1,11 +1,21 @@
-/* Spotify Web API, Kotlin Wrapper; MIT License, 2017-2021; Original author: Adam Ratzman */
 package com.adamratzman.spotify.utils
 
+import android.annotation.SuppressLint
 import android.graphics.Bitmap
 import android.graphics.BitmapFactory
 import android.util.Base64
 import java.io.ByteArrayOutputStream
 import java.net.URL
+import java.net.URLEncoder
+import java.text.SimpleDateFormat
+import java.util.Date
+
+internal actual fun String.encodeUrl() = URLEncoder.encode(this, "UTF-8")!!
+
+@SuppressLint("SimpleDateFormat")
+internal actual fun formatDate(format: String, date: Long): String {
+    return SimpleDateFormat(format).format(Date(date))
+}
 
 internal actual fun encodeBufferedImageToBase64String(image: BufferedImage): String {
     val byteArrayOutputStream = ByteArrayOutputStream()
@@ -23,3 +33,16 @@ internal actual fun convertUrlPathToBufferedImage(url: String): BufferedImage {
         BitmapFactory.decodeStream(inputStream)
     }
 }
+
+/**
+ * Actual platform that this program is run on.
+ */
+public actual val currentApiPlatform: Platform = Platform.ANDROID
+
+public actual typealias ConcurrentHashMap<K, V> = java.util.concurrent.ConcurrentHashMap<K, V>
+
+public actual typealias BufferedImage = Bitmap // TODO
+
+public actual typealias File = java.io.File
+
+public actual fun <K, V> ConcurrentHashMap<K, V>.asList(): List<Pair<K, V>> = toList()

src/androidMain/kotlin/com/adamratzman/spotify/http/Endpoints.kt

@@ -863,7 +863,8 @@ public class SpotifyUserAuthorization(
  * @param requiredScopes Scopes that your application requires to function (only applicable to [SpotifyClientApi] and [SpotifyImplicitGrantApi]).
  * @param proxyBaseUrl Provide if you have a proxy base URL that you would like to use instead of the Spotify API base
  * (https://api.spotify.com/v1).
- * @param retryIfInternalServerError Whether to retry once if an internal server error (500..599) has been received
+ * @param retryOnInternalServerErrorTimes Whether and how often to retry once if an internal server error (500..599) has been received. Set to 0
+ * to avoid retrying at all, or set to null to keep retrying until success.
  *
  */
 public data class SpotifyApiOptions(
@@ -881,5 +882,5 @@ public data class SpotifyApiOptions(
     public var onTokenRefresh: (suspend (GenericSpotifyApi) -> Unit)? = null,
     public var requiredScopes: List<SpotifyScope>? = null,
     public var proxyBaseUrl: String? = null,
-    public var retryIfInternalServerError: Boolean = true
+    public var retryOnInternalServerErrorTimes: Int? = 5,
 )

src/androidMain/kotlin/com/adamratzman/spotify/utils/Concurrency.kt

@@ -30,14 +30,14 @@ import com.adamratzman.spotify.http.HttpRequestMethod
 import com.adamratzman.spotify.http.HttpResponse
 import com.adamratzman.spotify.http.SpotifyEndpoint
 import com.adamratzman.spotify.http.SpotifyRequest
-import com.adamratzman.spotify.http.base64ByteEncode
 import com.adamratzman.spotify.models.AuthenticationError
 import com.adamratzman.spotify.models.Token
 import com.adamratzman.spotify.models.TokenValidityResponse
 import com.adamratzman.spotify.models.serialization.toObject
 import com.adamratzman.spotify.utils.asList
-import kotlin.jvm.JvmOverloads
+import com.adamratzman.spotify.utils.base64ByteEncode
 import kotlinx.serialization.json.Json
+import kotlin.jvm.JvmOverloads
 
 /**
  * Represents an instance of the Spotify API client, with common
@@ -69,7 +69,6 @@ public sealed class SpotifyApi<T : SpotifyApi<T, B>, B : ISpotifyApiBuilder<T, B
 
             field = value
         }
-    public val logger: SpotifyLogger = SpotifyLogger(spotifyApiOptions.enableLogger)
     public val expireTime: Long get() = token.expiresAt
     public var runExecutableFunctions: Boolean = true
 
@@ -150,15 +149,6 @@ public sealed class SpotifyApi<T : SpotifyApi<T, B>, B : ISpotifyApiBuilder<T, B
         endpoints.forEach { it.cache.clear() }
     }
 
-    /**
-     * Allows enabling and disabling the logger
-     *
-     * @param enable Whether to enable the logger
-     */
-    public fun useLogger(enable: Boolean) {
-        logger.enabled = enable
-    }
-
     /**
      * Create a Spotify authorization URL from which client access can be obtained
      *
@@ -622,8 +612,7 @@ public open class SpotifyClientApi(
                 ).execute()
             }
 
-            if (response.responseCode / 200 == 1) {
-                api.logger.logInfo("Successfully refreshed the Spotify token")
+            if (response.responseCode in 200..399) {
                 response.body.toObject(Token.serializer(), api, api.spotifyApiOptions.json)
             } else throw BadRequestException(
                 response.body.toObject(