add mimetype is image check for binary content and upgrade mime types

core/api/src/commonMain/kotlin/com/insanusmokrassar/postssystem/core/content/Content.kt

@@ -33,6 +33,9 @@ data class BinaryContent(
     val dataAllocator: ByteArrayAllocator
 ) : Content()
 
+val BinaryContent.isImage: Boolean
+    get() = mimeType is KnownMimeTypes.Image
+
 /**
  * Content which is already registered in database. Using its [id] you can retrieve all known
  * [com.insanusmokrassar.postssystem.core.post.RegisteredPost]s by using

utils/common/src/commonMain/kotlin/com/insanusmokrassar/postssystem/utils/common/KnownMimeTypes.kt

@@ -0,0 +1,32 @@
+package com.insanusmokrassar.postssystem.utils.common
+
+import kotlinx.serialization.Serializable
+
+@Serializable(MimeTypeSerializer::class)
+interface MimeType {
+    val raw: String
+}
+data class CustomMimeType(override val raw: String) : MimeType
+
+private const val imageMainType = "image"
+
+sealed class KnownMimeTypes(override val raw: String) : MimeType {
+    object Any : MimeType, KnownMimeTypes("*/*")
+    sealed class Image(raw: String) : MimeType, KnownMimeTypes(raw) {
+        object Any : Image("$imageMainType/*")
+        object Gif : Image("$imageMainType/gif")
+        object Jpeg : Image("$imageMainType/jpeg")
+        object PNG : Image("$imageMainType/png")
+    }
+}
+
+internal val knownMimeTypes: Set<MimeType> = setOf(
+    KnownMimeTypes.Any,
+    KnownMimeTypes.Image.Any,
+    KnownMimeTypes.Image.Gif,
+    KnownMimeTypes.Image.Jpeg,
+    KnownMimeTypes.Image.PNG
+)
+fun findBuiltinMimeType(from: String): MimeType? {
+    return knownMimeTypes.firstOrNull { it.raw == from }
+}

utils/common/src/commonMain/kotlin/com/insanusmokrassar/postssystem/utils/common/MimeTypeTools.kt

@@ -2,18 +2,15 @@ package com.insanusmokrassar.postssystem.utils.common
 
 import kotlinx.serialization.*
 
-private val mimesCache = mutableMapOf<String, MimeType>()
-
-@Serializable(MimeTypeSerializer::class)
-expect class MimeType {
-    val raw: String
+private val mimesCache = mutableMapOf<String, MimeType>().also {
+    knownMimeTypes.forEach { mimeType -> it[mimeType.raw] = mimeType }
 }
 
 fun mimeType(raw: String) = mimesCache.getOrPut(raw) {
     parseMimeType(raw)
 }
 
-internal expect fun parseMimeType(raw: String): MimeType
+internal fun parseMimeType(raw: String): MimeType = findBuiltinMimeType(raw) ?: CustomMimeType(raw)
 
 @Serializer(MimeType::class)
 internal object MimeTypeSerializer : KSerializer<MimeType> {

utils/common/src/jsMain/kotlin/com/insanusmokrassar/postssystem/utils/common/MimeType.kt

@@ -1,19 +0,0 @@
-package com.insanusmokrassar.postssystem.utils.common
-
-import kotlinx.serialization.*
-import org.w3c.dom.get
-import kotlin.browser.window
-
-private val mimesCache = mutableMapOf<String, MimeType>()
-
-@Serializable(MimeTypeSerializer::class)
-actual class MimeType(
-    actual val raw: String
-) {
-    @Transient
-    val jsMimeType = window.navigator.mimeTypes[raw]
-
-    override fun toString(): String = raw
-}
-
-actual fun parseMimeType(raw: String) = MimeType(raw)

utils/common/src/jsMain/kotlin/com/insanusmokrassar/postssystem/utils/common/MimeTypeTools.kt

@@ -0,0 +1,7 @@
+package com.insanusmokrassar.postssystem.utils.common
+
+import org.w3c.dom.get
+import kotlin.browser.window
+
+val MimeType.jsMimeType
+    get() = window.navigator.mimeTypes[raw]

utils/common/src/jvmMain/kotlin/com/insanusmokrassar/postssystem/utils/common/MimeType.kt

@@ -1,13 +0,0 @@
-package com.insanusmokrassar.postssystem.utils.common
-
-import kotlinx.serialization.*
-
-private val mimesCache = mutableMapOf<String, MimeType>()
-
-@Serializable(MimeTypeSerializer::class)
-actual class MimeType(
-    actual val raw: String
-) : javax.activation.MimeType(raw)
-
-actual fun parseMimeType(raw: String): MimeType = MimeType(raw)
-

utils/common/src/jvmMain/kotlin/com/insanusmokrassar/postssystem/utils/common/MimeTypeTools.kt

@@ -0,0 +1,5 @@
+package com.insanusmokrassar.postssystem.utils.common
+
+val MimeType.asActivationMimeType: javax.activation.MimeType
+    get() = javax.activation.MimeType(raw)
+