empty cards have owners, clogs and duds should work

board.go

@@ -23,6 +23,7 @@ func (b *Board) GetRow(id int) []*Card {
 		return b.Scourge[:]
 	} else {
 		log.Println("asked for invalid row")
+		panic("bad row")
 		return nil
 	}
 }
@@ -38,16 +39,27 @@ func (b *Board) GetCard(id int, pos int) *Card {
 func (b *Board) Remove(c *Card) {
 	for k, v := range b.Sentinal {
 		if v.Id == c.Id {
-			b.Sentinal[k] = NewEmpty(k)
+			b.Sentinal[k] = NewEmpty(c.Owner, k)
 		}
 	}
 	for k, v := range b.Scourge {
 		if v.Id == c.Id {
-			b.Scourge[k] = NewEmpty(k)
+			b.Scourge[k] = NewEmpty(c.Owner, k)
 		}
 	}
 }
 
+func (b *Board) Replace(old *Card, neo *Card) {
+	if old.Owner == SentinalID {
+		b.Sentinal[old.Position] = neo
+	} else if old.Owner == ScourgeID {
+		b.Scourge[old.Position] = neo
+	} else {
+		log.Printf("can't replace a card with bad owner:%v", old.Owner)
+		return
+	}
+}
+
 func (b *Board) Empty(id int) bool {
 	res := true
 	row := b.GetRow(id)
@@ -81,7 +93,7 @@ func (b *Board) Move(id, src, dest int) bool {
 	brd := b.GetRow(id)
 	brd[dest] = brd[src]
 	brd[dest].Position = dest
-	brd[src] = NewEmpty(src)
+	brd[src] = NewEmpty(brd[dest].Owner, src)
 	return true
 }
 

card.go

@@ -2,6 +2,7 @@ package tome_lib
 
 import (
 	"fmt"
+	"log"
 
 	"github.com/google/uuid"
 )
@@ -21,7 +22,12 @@ type Card struct {
 	Effects   []*Effect `json:"effects"`
 }
 
-func NewEmpty(p int) *Card {
+func NewEmpty(o, p int) *Card {
+	if o != ScourgeID && o != SentinalID {
+		log.Printf("Need valid owner for empty card:%v", o)
+		panic("err")
+		return nil
+	}
 	return &Card{
 		Type:      EmptyValue,
 		BasePower: -1,
@@ -29,7 +35,7 @@ func NewEmpty(p int) *Card {
 		Id:        uuid.New(),
 		Sick:      false,
 		Counters:  0,
-		Owner:     -1,
+		Owner:     o,
 		Position:  p,
 		Spell:     false,
 		Token:     false,