feat: add picker component

picker/intstate.go

@@ -0,0 +1,82 @@
+package picker
+
+type IntState struct {
+ min int
+ max int
+ selection int
+ ignoreMin bool
+ ignoreMax bool
+}
+
+func NewIntState(min, max, selection int, ignoreMin, ignoreMax bool) *IntState {
+ switch {
+ case selection < min && !ignoreMin:
+ selection = min
+ case selection > max && !ignoreMax:
+ selection = max
+ }
+
+ return &IntState{
+ min: min,
+ max: max,
+ ignoreMin: ignoreMin,
+ ignoreMax: ignoreMax,
+ selection: selection,
+ }
+}
+
+func (s *IntState) GetValue() interface{} {
+ return s.selection
+}
+
+func (s *IntState) NextExists() bool {
+ return s.ignoreMax ||
+ s.selection < s.max
+}
+
+func (s *IntState) PrevExists() bool {
+ return s.ignoreMin ||
+ s.selection > s.min
+}
+
+func (s *IntState) Next(canCycle bool) {
+ switch {
+ case s.NextExists():
+ s.selection++
+
+ case canCycle:
+ s.selection = s.min
+ }
+}
+
+func (s *IntState) Prev(canCycle bool) {
+ switch {
+ case s.PrevExists():
+ s.selection--
+
+ case canCycle:
+ s.selection = s.max
+ }
+}
+
+func (s *IntState) StepForward(size int) {
+ s.selection += size
+ if s.selection > s.max && !s.ignoreMax {
+ s.selection = s.max
+ }
+}
+
+func (s *IntState) StepBackward(size int) {
+ s.selection -= size
+ if s.selection < s.min && !s.ignoreMin {
+ s.selection = s.min
+ }
+}
+
+func (s *IntState) JumpForward() {
+ s.selection = s.max
+}
+
+func (s *IntState) JumpBackward() {
+ s.selection = s.min
+}