package monitoring

import "strings"

type KeyValueVisitor struct {
	cb    func(key string, value interface{})
	level []string
}

func NewKeyValueVisitor(cb func(string, interface{})) *KeyValueVisitor {
	return &KeyValueVisitor{cb: cb}
}

func (vs *KeyValueVisitor) OnRegistryStart() {}

func (vs *KeyValueVisitor) OnRegistryFinished() {
	if len(vs.level) > 0 {
		vs.dropName()
	}
}

func (vs *KeyValueVisitor) OnKey(name string) {
	vs.level = append(vs.level, name)
}

func (vs *KeyValueVisitor) getName() string {
	defer vs.dropName()
	if len(vs.level) == 1 {
		return vs.level[0]
	}
	return strings.Join(vs.level, ".")
}

func (vs *KeyValueVisitor) dropName() {
	vs.level = vs.level[:len(vs.level)-1]
}

func (vs *KeyValueVisitor) OnString(s string) { vs.cb(vs.getName(), s) }
func (vs *KeyValueVisitor) OnBool(b bool)     { vs.cb(vs.getName(), b) }
func (vs *KeyValueVisitor) OnNil()            { vs.cb(vs.getName(), nil) }
func (vs *KeyValueVisitor) OnInt(i int64)     { vs.cb(vs.getName(), i) }
func (vs *KeyValueVisitor) OnFloat(f float64) { vs.cb(vs.getName(), f) }