Add adapter for Fever folders api call

api/src/main/java/com/readrops/api/services/fever/adapters/FeverFoldersAdapter.kt

@@ -0,0 +1,62 @@
+package com.readrops.api.services.fever.adapters
+
+import android.annotation.SuppressLint
+import com.readrops.api.utils.exceptions.ParseException
+import com.readrops.api.utils.extensions.nextNonEmptyString
+import com.readrops.api.utils.extensions.skipField
+import com.readrops.api.utils.extensions.skipToEnd
+import com.readrops.db.entities.Folder
+import com.squareup.moshi.FromJson
+import com.squareup.moshi.JsonReader
+import com.squareup.moshi.ToJson
+
+class FeverFoldersAdapter {
+
+    @ToJson
+    fun toJson(folders: List<Folder>) = ""
+
+    @SuppressLint("CheckResult")
+    @FromJson
+    fun fromJson(reader: JsonReader): List<Folder> = with(reader) {
+        return try {
+            val folders = arrayListOf<Folder>()
+
+            beginObject()
+
+            repeat(3) {
+                skipField()
+            }
+
+            nextName() // beginning of folders array
+            beginArray()
+
+            while (hasNext()) {
+                beginObject()
+
+                val folder = Folder()
+                while (hasNext()) {
+                    with(folder) {
+                        when (selectName(NAMES)) {
+                            0 -> remoteId = nextInt().toString()
+                            1 -> name = nextNonEmptyString()
+                        }
+                    }
+                }
+
+                folders += folder
+                endObject()
+            }
+
+            endArray()
+            skipToEnd()
+
+            folders
+        } catch (e: Exception) {
+            throw ParseException(e.message)
+        }
+    }
+
+    companion object {
+        val NAMES: JsonReader.Options = JsonReader.Options.of("id", "title")
+    }
+}

api/src/main/java/com/readrops/api/utils/extensions/JsonReaderExtensions.kt

@@ -13,3 +13,14 @@ fun JsonReader.nextNonEmptyString(): String {
 
 fun JsonReader.nextNullableInt(): Int? =
         if (peek() != JsonReader.Token.NULL) nextInt() else nextNull()
+
+fun JsonReader.skipField() {
+    skipName()
+    skipValue()
+}
+
+fun JsonReader.skipToEnd() {
+    while (hasNext()) {
+        skipField()
+    }
+}

api/src/test/java/com/readrops/api/services/fever/adapters/FeverFoldersAdapterTest.kt

@@ -0,0 +1,31 @@
+package com.readrops.api.services.fever.adapters
+
+import com.readrops.api.TestUtils
+import com.readrops.db.entities.Folder
+import com.squareup.moshi.Moshi
+import com.squareup.moshi.Types
+import okio.Buffer
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class FeverFoldersAdapterTest {
+
+    private val adapter = Moshi.Builder()
+        .add(FeverFoldersAdapter())
+        .build()
+        .adapter<List<Folder>>(Types.newParameterizedType(List::class.java, Folder::class.java))
+
+    @Test
+    fun validFoldersTest() {
+        val stream = TestUtils.loadResource("services/fever/folders.json")
+
+        val folders = adapter.fromJson(Buffer().readFrom(stream))!!
+
+        with(folders[0]) {
+            assertEquals(name, "Libre")
+            assertEquals(remoteId, "4")
+        }
+
+
+    }
+}

api/src/test/resources/services/fever/folders.json

@@ -0,0 +1,17 @@
+{
+  "api_version": 3,
+  "auth": 1,
+  "last_refreshed_on_time": 1635849601,
+  "groups": [
+    {
+      "id": 4,
+      "title": "Libre"
+    }
+  ],
+  "feeds_groups": [
+    {
+      "group_id": 3,
+      "feed_ids": "5,4"
+    }
+  ]
+}