Simplify indifferent access to sets

internal/sets/sets.go

@@ -18,6 +18,8 @@ type MapSet struct {
 	RightCount   int
 	CenterCount  int
 
+	Palette []string
+
 	// TODO: is there any more structure than this? Should I preserve empty lines?
 	SurfacePalette []string
 	LeftPalette    []string
@@ -25,6 +27,10 @@ type MapSet struct {
 	CenterPalette  []string
 }
 
+func (m *MapSet) Count() int {
+	return m.SurfaceCount + m.LeftCount + m.RightCount + m.CenterCount
+}
+
 func LoadSets(dir string) (map[string]*MapSet, error) {
 	fis, err := ioutil.ReadDir(dir)
 	if err != nil {
@@ -73,17 +79,24 @@ func LoadSet(filename string) (*MapSet, error) {
 		return nil, err
 	}
 
-	if err := consumePalette(s, out.SurfaceCount, &out.SurfacePalette); err != nil {
+	fmt.Println(filename)
-		return nil, fmt.Errorf("Failed to read surface palette: %v", err)
+	out.Palette = make([]string, out.Count())
-	}
+	offset := 0
-	if err := consumePalette(s, out.LeftCount, &out.LeftPalette); err != nil {
+
-		return nil, fmt.Errorf("Failed to read left palette: %v", err)
+	out.SurfacePalette = out.Palette[offset : offset+out.SurfaceCount : offset+out.SurfaceCount]
-	}
+	offset += out.SurfaceCount
-	if err := consumePalette(s, out.RightCount, &out.RightPalette); err != nil {
+
-		return nil, fmt.Errorf("Failed to read right palette: %v", err)
+	out.LeftPalette = out.Palette[offset : offset+out.LeftCount : offset+out.LeftCount]
-	}
+	offset += out.LeftCount
-	if err := consumePalette(s, out.CenterCount, &out.CenterPalette); err != nil {
+
-		return nil, fmt.Errorf("Failed to read center palette: %v", err)
+	out.RightPalette = out.Palette[offset : offset+out.RightCount : offset+out.RightCount]
+	offset += out.RightCount
+
+	out.CenterPalette = out.Palette[offset : offset+out.CenterCount : offset+out.CenterCount]
+	offset += out.CenterCount
+
+	if err := consumePalette(s, out.Palette); err != nil {
+		return nil, fmt.Errorf("Failed to read palette: %v", err)
 	}
 
 	return out, nil
@@ -128,18 +141,15 @@ func consumeDefs(scanner *asciiscan.Scanner, in *MapSet) error {
 	return nil
 }
 
-func consumePalette(scanner *asciiscan.Scanner, n int, in *[]string) error {
+func consumePalette(scanner *asciiscan.Scanner, into []string) error {
-	out := make([]string, 0, n)
+	for i := 0; i < len(into); i++ {
-
-	for i := 0; i < n; i++ {
 		str, err := scanner.ConsumeString()
 		if err != nil {
 			return err // EOF is bad: the number of entries is explicit
 		}
 
-		out = append(out, str)
+		into[i] = str
 	}
 
-	*in = out
 	return nil
 }