Add split_tree and ability to create splits

cmd/micro/split_tree.go

@@ -0,0 +1,152 @@
+package main
+
+type SplitType bool
+
+const (
+	VerticalSplit   = false
+	HorizontalSplit = true
+)
+
+type Node interface {
+	VSplit(buf *Buffer)
+	HSplit(buf *Buffer)
+	String() string
+}
+
+type LeafNode struct {
+	view *View
+
+	parent *SplitTree
+}
+
+func NewLeafNode(v *View, parent *SplitTree) *LeafNode {
+	n := new(LeafNode)
+	n.view = v
+	n.view.splitNode = n
+	n.parent = parent
+	return n
+}
+
+type SplitTree struct {
+	kind SplitType
+
+	parent   *SplitTree
+	children []Node
+
+	x int
+	y int
+
+	width  int
+	height int
+
+	tabNum int
+}
+
+func (l *LeafNode) VSplit(buf *Buffer) {
+	tab := tabs[l.parent.tabNum]
+	if l.parent.kind == VerticalSplit {
+		newView := NewView(buf)
+		newView.TabNum = l.parent.tabNum
+		newView.Num = len(tab.views)
+		l.parent.children = append(l.parent.children, NewLeafNode(newView, l.parent))
+
+		tab.curView++
+		tab.views = append(tab.views, newView)
+	} else {
+		s := new(SplitTree)
+		s.kind = VerticalSplit
+		s.parent = l.parent
+		newView := NewView(buf)
+		newView.TabNum = l.parent.tabNum
+		newView.Num = len(tab.views)
+		s.children = []Node{l, NewLeafNode(newView, s)}
+		l.parent.children[search(l.parent.children, l)] = s
+
+		tab.curView++
+		tab.views = append(tab.views, newView)
+	}
+}
+
+func (l *LeafNode) HSplit(buf *Buffer) {
+	tab := tabs[l.parent.tabNum]
+	if l.parent.kind == HorizontalSplit {
+		newView := NewView(buf)
+		newView.TabNum = l.parent.tabNum
+		newView.Num = len(tab.views)
+		l.parent.children = append(l.parent.children, NewLeafNode(newView, l.parent))
+
+		tab.curView++
+		tab.views = append(tab.views, newView)
+	} else {
+		s := new(SplitTree)
+		s.kind = HorizontalSplit
+		s.parent = l.parent
+		newView := NewView(buf)
+		newView.TabNum = l.parent.tabNum
+		newView.Num = len(tab.views)
+		s.children = []Node{l, NewLeafNode(newView, s)}
+		l.parent.children[search(l.parent.children, l)] = s
+
+		tab.curView++
+		tab.views = append(tab.views, newView)
+	}
+}
+
+func (s *SplitTree) ResizeSplits() {
+	for i, node := range s.children {
+		if n, ok := node.(*LeafNode); ok {
+			if s.kind == VerticalSplit {
+				n.view.width = s.width / len(s.children)
+				n.view.height = s.height
+
+				n.view.x = s.x + n.view.width*i
+				n.view.y = s.y
+			} else {
+				n.view.height = s.height / len(s.children)
+				n.view.width = s.width
+
+				n.view.y = s.y + n.view.height*i
+				n.view.x = s.x
+			}
+		} else if n, ok := node.(*SplitTree); ok {
+			if s.kind == VerticalSplit {
+				n.width = s.width / len(s.children)
+				n.height = s.height
+
+				n.x = s.x + n.width*i
+				n.y = s.y
+			} else {
+				n.height = s.height / len(s.children)
+				n.width = s.width
+
+				n.y = s.y + n.height*i
+				n.x = s.x
+			}
+			n.ResizeSplits()
+		}
+	}
+}
+
+func (l *LeafNode) String() string {
+	return l.view.Buf.Name
+}
+
+func search(haystack []Node, needle Node) int {
+	for i, x := range haystack {
+		if x == needle {
+			return i
+		}
+	}
+	return 0
+}
+
+func (s *SplitTree) VSplit(buf *Buffer) {}
+func (s *SplitTree) HSplit(buf *Buffer) {}
+
+func (s *SplitTree) String() string {
+	str := "["
+	for _, child := range s.children {
+		str += child.String() + ", "
+	}
+	return str + "]"
+}