add post preview

features/posts/common/build.gradle

@@ -0,0 +1,18 @@
+plugins {
+    id "org.jetbrains.kotlin.multiplatform"
+    id "org.jetbrains.kotlin.plugin.serialization"
+    id "com.android.library"
+}
+
+apply from: "$mppProjectWithSerializationPresetPath"
+
+kotlin {
+    sourceSets {
+        commonMain {
+            dependencies {
+                api project(":postssystem.features.common.common")
+                api project(":postssystem.features.content.common")
+            }
+        }
+    }
+}

features/posts/common/src/commonMain/kotlin/dev/inmo/postssystem/features/posts/common/Post.kt

@@ -0,0 +1,47 @@
+package dev.inmo.postssystem.features.posts.common
+
+import com.soywiz.klock.DateTime
+import dev.inmo.postssystem.features.common.common.DateTimeSerializer
+import dev.inmo.postssystem.features.content.common.ContentId
+import kotlinx.serialization.Serializable
+import kotlin.jvm.JvmInline
+
+/**
+ * Identifier of [RegisteredPost] in system
+ */
+@Serializable
+@JvmInline
+value class PostId(val long: Long) {
+    override fun toString(): String = long.toString()
+}
+typealias ContentIds = List<ContentId>
+
+/**
+ * Base interface for creating of new post
+ *
+ * @see NewPost
+ * @see RegisteredPost
+ */
+@Serializable
+sealed class Post {
+    abstract val content: ContentIds
+}
+
+/**
+ * This type of [Post] should be used in case you wish to register new post in system
+ */
+@Serializable
+data class NewPost(
+    override val content: ContentIds
+) : Post()
+
+/**
+ * Registered [Post]
+ */
+@Serializable
+data class RegisteredPost(
+    val id: PostId,
+    override val content: ContentIds,
+    @Serializable(DateTimeSerializer::class)
+    val creationDate: DateTime
+) : Post()

features/posts/common/src/main/AndroidManifest.xml

@@ -0,0 +1 @@
+<manifest package="dev.inmo.postssystem.features.posts.common"/>