package solutions.bitbadger.documents

import kotlinx.serialization.json.Json
import java.sql.Connection
import java.sql.DriverManager

object Configuration {

    /**
     * JSON serializer; replace to configure with non-default options
     *
     * The default sets `encodeDefaults` to `true` and `explicitNulls` to `false`; see
     * https://github.com/Kotlin/kotlinx.serialization/blob/master/docs/json.md for all configuration options
     */
    var json = Json {
        encodeDefaults = true
        explicitNulls  = false
    }

    /** The field in which a document's ID is stored */
    var idField = "id"

    /** The automatic ID strategy to use */
    var autoIdStrategy = AutoId.DISABLED

    /** The length of automatic random hex character string */
    var idStringLength = 16

    /** The derived dialect value from the connection string */
    internal var dialectValue: Dialect? = null

    /** The connection string for the JDBC connection */
    var connectionString: String? = null
        set(value) {
            field = value
            dialectValue = if (value.isNullOrBlank()) null else Dialect.deriveFromConnectionString(value)
        }

    /**
     * Retrieve a new connection to the configured database
     *
     * @return A new connection to the configured database
     * @throws IllegalArgumentException If the connection string is not set before calling this
     */
    fun dbConn(): Connection {
        if (connectionString == null) {
            throw IllegalArgumentException("Please provide a connection string before attempting data access")
        }
        return DriverManager.getConnection(connectionString)
    }

    /**
     * The dialect in use
     *
     * @param process The process being attempted
     * @return The dialect for the current connection
     * @throws DocumentException If the dialect has not been set
     */
    fun dialect(process: String? = null): Dialect =
        dialectValue ?: throw DocumentException(
            "Database mode not set" + if (process == null) "" else "; cannot $process")
}