intro

import co.q64.rain.api.core.database.Data
import co.q64.rain.api.core.database.Database
import co.q64.rain.api.core.database.Storage
import co.q64.rain.api.core.database.data
import co.q64.rain.api.core.database.get
import co.q64.rain.api.core.model.PlayerId
import co.q64.raindrop.annotation.Generate
import org.springframework.stereotype.Component

@Generate.Optics
data class SamplePlayerData(
    override val id: String,
    override val version: Int = CurrentVersion,

    val experience: Int = 0
) : Data {
    companion object {
        const val CurrentVersion = 1
    }
}

@Component
class ExperienceGetter(
    private val database: Database
) {
    suspend fun getExperienceOrNull(player: PlayerId): Int? {
        // We can grab the entire data object if needed
        val entireObject: SamplePlayerData? = database.data<SamplePlayerData>(player)

        // But in this case, we're only interested in experience
        // So the preferred method here would be to use the generated Optic
        val experience: Int? = database.data(player, SamplePlayerData.Experience)

        // database.data always returns a nullable value, since a lookup can fail
        // Under typical conditions, the result will never be null, since default
        // data objects are created when needed

        // A result of null indicates that some part of the database infrastructure
        // was unavailable. Alternatively, database.get can be used when more information
        // about a potential error is desired
        return when (val result = database.get(player, SamplePlayerData.Experience)) {
            is Storage.Get.Fail -> {
                // Do something useful with the message
                val message = result.message
                // Then return null
                null
            }
            is Storage.Get.Success -> {
                result.data
            }
        }
    }
}

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