commonMain.entity.optional.OptionalLong.kt Maven / Gradle / Ivy
package dev.kord.common.entity.optional
import kotlinx.serialization.KSerializer
import kotlinx.serialization.Serializable
import kotlinx.serialization.descriptors.PrimitiveKind
import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
import kotlinx.serialization.descriptors.SerialDescriptor
import kotlinx.serialization.encoding.Decoder
import kotlinx.serialization.encoding.Encoder
/**
* Represents a value that encapsulate [the optional and value state of a Long in the Discord API](https://discord.com/developers/docs/reference#nullable-and-optional-resource-fields).
* Specifically:
* * [Missing] - a Long field that was not present in the serialized entity.
* * [Value] - a Long field that was assigned a non-null value in the serialized entity.
*
* > Note that there is no nullable variant present. Use Long? or `OptionalLong?` for this case instead.
*
* The base class is (de)serializable with kotlinx.serialization.
*
* Note that kotlinx.serialization does **not** call serializers for values that are not
* present in the serialized format. `Optional` fields should have a default value of `OptionalLong.Missing`:
*
* ```kotlin
* @Serializable
* class DiscordUser(
* val id: Long,
* val username: String,
* val bot: OptionalLong = OptionalLong.Missing
* )
* ```
*/
@Serializable(with = OptionalLong.Serializer::class)
public sealed class OptionalLong {
public val asNullable: Long?
get() = when (this) {
Missing -> null
is Value -> value
}
public val asOptional: Optional
get() = when (this) {
Missing -> Optional.Missing()
is Value -> Optional.Value(value)
}
/**
* returns [default] if the optional is [Missing], or [Value.value] if is [Value].
*/
public fun orElse(default: Long): Long = when (this) {
Missing -> default
is Value -> value
}
/**
* Represents a Long field that was not present in the serialized entity.
*/
public object Missing : OptionalLong() {
override fun toString(): String = "OptionalLong.Missing"
}
/**
* Represents a field that was assigned a non-null value in the serialized entity.
* Equality and hashcode is implemented through its [value].
*
* @param value the value this optional wraps.
*/
public class Value(public val value: Long) : OptionalLong() {
/**
* Destructures this optional to its [value].
*/
public operator fun component1(): Long = value
override fun toString(): String = "Optional.Value(value=$value)"
override fun equals(other: Any?): Boolean {
val value = other as? Value ?: return false
return value.value == this.value
}
override fun hashCode(): Int = value.hashCode()
}
internal object Serializer : KSerializer {
override val descriptor: SerialDescriptor
get() = PrimitiveSerialDescriptor("Kord.OptionalLong", PrimitiveKind.LONG)
override fun deserialize(decoder: Decoder): OptionalLong = Value(decoder.decodeLong())
override fun serialize(encoder: Encoder, value: OptionalLong) = when (value) {
Missing -> Unit//ignore value
is Value -> encoder.encodeLong(value.value)
}
}
}
/**
* returns `null` if this is `null`, calls [OptionalLong.asNullable] otherwise.
*/
public val OptionalLong?.asNullable: Long? get() = this?.asNullable
/**
* returns `null` if this is `null`, calls [OptionalLong.asNullable] otherwise.
*/
public val OptionalLong?.value: Long? get() = this?.asNullable
/**
* returns [default] if this is `null`, calls [OptionalLong.asNullable] otherwise.
*/
public fun OptionalLong?.orElse(default: Long): Long = this?.orElse(default) ?: default
public fun Long?.optional(): OptionalLong = if (this == null) OptionalLong.Missing else OptionalLong.Value(this)