package tf.bug.cats

import cats._
import cats.data._
import cats.implicits._
import scalax.collection.Graph
import scalax.collection.GraphPredef._, scalax.collection.GraphEdge._
import tf.bug.cataquack.{Read, Storage}

case class IDCat(id: Int, name: String, friends: Set[Int]) {
  def asNode: CatNode = CatNode(id, name)
}
case class CatNode(id: Int, name: String)

object Cat {

  def getCats[F[_]: Functor, T](s: Storage[F, T])(implicit read: Read[T, Vector[IDCat]]): F[Vector[IDCat]] = {
    s.get("cats").map(read.apply)
  }

  def getCatGraphFromVec[F[_]: Functor, T](s: Storage[F, T])(implicit read: Read[T, Vector[IDCat]]): F[Graph[CatNode, UnDiEdge]] = {
    getCats(s).map(cats => {
      val emptyGraph = Graph.empty[CatNode, UnDiEdge]
      cats.foldLeft(emptyGraph)((g, nc) => g ++ nc.friends.map(friendID => {
        val fc = cats.find(_.id == friendID)
        fc.map(rdc => {
          val ncd = nc.asNode
          val nrd = rdc.asNode
          ncd ~ nrd
        })
      }).filter(_.isDefined).map(_.get))
    })
  }

  def getCatGraph[F[_]: Functor, T](s: Storage[F, T])(implicit read: Read[T, Graph[CatNode, UnDiEdge]]): F[Graph[CatNode, UnDiEdge]] = {
    s.get("cats").map(read.apply)
  }

}