package api

import org.json4s._
import org.json4s.jackson.Serialization
import scala.util.Try
import org.joda.time.format._
import org.joda.time.DateTime
import org.joda.time.DateTimeZone
import java.util.Date


object JsonFormat {
  case class Context(baseUrl:String)
  val parserISO = DateTimeFormat.forPattern("yyyy-MM-dd'T'HH:mm:ss'Z'")
  val jsonFormats = Serialization.formats(NoTypeHints) + new CustomSerializer[Date](format =>
    (
      { case JString(s) => Try(parserISO.parseDateTime(s)).toOption.map(_.toDate)
        .getOrElse(throw new MappingException("Can't convert " + s + " to Date")) },
      { case x: Date => JString(parserISO.print(new DateTime(x).withZone(DateTimeZone.UTC))) }
    )
  ) + FieldSerializer[ApiUser]() + FieldSerializer[ApiPullRequest]() + FieldSerializer[ApiRepository]() +
    FieldSerializer[ApiCommitListItem.Parent]() + FieldSerializer[ApiCommitListItem]() + FieldSerializer[ApiCommitListItem.Commit]() +
    FieldSerializer[ApiCommitStatus]() + FieldSerializer[ApiCommit]() + FieldSerializer[ApiCombinedCommitStatus]() +
    FieldSerializer[ApiPullRequest.Commit]()
  def apiPathSerializer(c: Context) = new CustomSerializer[ApiPath](format =>
      (
        {
          case JString(s) if s.startsWith(c.baseUrl) => ApiPath(s.substring(c.baseUrl.length))
          case JString(s) => throw new MappingException("Can't convert " + s + " to ApiPath")
        },
        {
          case ApiPath(path) => JString(c.baseUrl+path)
        }
      )
    )
  /**
   * convert object to json string
   */
  def apply(obj: AnyRef)(implicit c: Context): String = Serialization.write(obj)(jsonFormats + apiPathSerializer(c))
}