BucketStorage.kt

package com.powersync.bucket

import com.powersync.db.SqlCursor
import com.powersync.db.StreamKey
import com.powersync.db.crud.CrudEntry
import com.powersync.db.internal.PowerSyncTransaction
import com.powersync.db.schema.Schema
import com.powersync.sync.Instruction
import com.powersync.utils.JsonUtil
import kotlinx.serialization.SerialName
import kotlinx.serialization.Serializable
import kotlinx.serialization.json.JsonObject

internal interface BucketStorage {
    fun getMaxOpId(): String

    suspend fun getClientId(): String

    suspend fun nextCrudItem(): CrudEntry?

    suspend fun nextCrudItem(transaction: PowerSyncTransaction): CrudEntry?

    suspend fun hasCrud(): Boolean

    suspend fun hasCrud(transaction: PowerSyncTransaction): Boolean

    fun mapCrudEntry(row: SqlCursor): CrudEntry

    suspend fun updateLocalTarget(checkpointCallback: suspend () -> String): Boolean

    suspend fun hasCompletedSync(): Boolean

    suspend fun control(args: PowerSyncControlArguments): List<Instruction>
}

internal sealed interface PowerSyncControlArguments {
    /**
     * Returns the arguments for the `powersync_control` SQL invocation.
     */
    val sqlArguments: Pair<String, Any?>

    @Serializable
    class Start(
        val parameters: JsonObject,
        val schema: Schema,
        @SerialName("include_defaults")
        val includeDefaults: Boolean,
        @SerialName("active_streams")
        val activeStreams: List<StreamKey>,
        @SerialName("app_metadata")
        val appMetadata: Map<String, String>,
    ) : PowerSyncControlArguments {
        override val sqlArguments: Pair<String, Any?>
            get() = "start" to JsonUtil.json.encodeToString(this)
    }

    data object Stop : PowerSyncControlArguments {
        override val sqlArguments: Pair<String, Any?> = "stop" to null
    }

    data class TextLine(
        val line: String,
    ) : PowerSyncControlArguments {
        override val sqlArguments: Pair<String, Any?> = "line_text" to line
    }

    class BinaryLine(
        line: ByteArray,
    ) : PowerSyncControlArguments {
        override fun toString(): String = "BinaryLine"

        override val sqlArguments: Pair<String, Any?> = "line_binary" to line
    }

    data object DidRefreshToken : PowerSyncControlArguments {
        override val sqlArguments: Pair<String, Any?> = "refreshed_token" to null
    }

    data object CompletedUpload : PowerSyncControlArguments {
        override val sqlArguments: Pair<String, Any?> = "completed_upload" to null
    }

    data object ConnectionEstablished : PowerSyncControlArguments {
        override val sqlArguments: Pair<String, Any?> = "connection" to "established"
    }

    data object ResponseStreamEnd : PowerSyncControlArguments {
        override val sqlArguments: Pair<String, Any?> = "connection" to "end"
    }

    class UpdateSubscriptions(
        activeStreams: List<StreamKey>,
    ) : PowerSyncControlArguments {
        override val sqlArguments: Pair<String, Any?> =
            "update_subscriptions" to JsonUtil.json.encodeToString(activeStreams)
    }
}