Move BlockStack into a separate file blockstack.go

blockstack.go

@@ -0,0 +1,74 @@
+package gold
+
+import (
+	"bytes"
+)
+
+type BlockElement struct {
+	Block *bytes.Buffer
+	Style *ElementStyle
+}
+
+type BlockStack []BlockElement
+
+func (s *BlockStack) Push(e BlockElement) {
+	*s = append(*s, e)
+}
+
+func (s *BlockStack) Pop() {
+	stack := *s
+	if len(stack) == 0 {
+		return
+	}
+
+	stack = stack[0 : len(stack)-1]
+	*s = stack
+}
+
+func (s BlockStack) Indent() uint {
+	var i uint
+
+	for _, v := range s {
+		if v.Style == nil {
+			continue
+		}
+		i += v.Style.Indent
+	}
+
+	return i
+}
+
+func (s BlockStack) Margin() uint {
+	var i uint
+
+	for _, v := range s {
+		if v.Style == nil {
+			continue
+		}
+		i += v.Style.Margin
+	}
+
+	return i
+}
+
+func (s BlockStack) Parent() BlockElement {
+	if len(s) < 2 {
+		return s.Current()
+	}
+
+	return s[len(s)-2]
+}
+
+func (s BlockStack) Current() BlockElement {
+	if len(s) == 0 {
+		return BlockElement{
+			Block: &bytes.Buffer{},
+		}
+	}
+
+	return s[len(s)-1]
+}
+
+func (s BlockStack) With(child *ElementStyle) *ElementStyle {
+	return cascadeStyle(s.Current().Style, child)
+}