// Copyright 2018 The Energi Core Authors
// Copyright 2018 The go-ethereum Authors
// This file is part of the Energi Core library.
//
// The Energi Core library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The Energi Core library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the Energi Core library. If not, see <http://www.gnu.org/licenses/>.

package metrics

import "testing"

func BenchmarkGuageFloat64(b *testing.B) {
	g := NewGaugeFloat64()
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		g.Update(float64(i))
	}
}

func TestGaugeFloat64(t *testing.T) {
	g := NewGaugeFloat64()
	g.Update(float64(47.0))
	if v := g.Value(); float64(47.0) != v {
		t.Errorf("g.Value(): 47.0 != %v\n", v)
	}
}

func TestGaugeFloat64Snapshot(t *testing.T) {
	g := NewGaugeFloat64()
	g.Update(float64(47.0))
	snapshot := g.Snapshot()
	g.Update(float64(0))
	if v := snapshot.Value(); float64(47.0) != v {
		t.Errorf("g.Value(): 47.0 != %v\n", v)
	}
}

func TestGetOrRegisterGaugeFloat64(t *testing.T) {
	r := NewRegistry()
	NewRegisteredGaugeFloat64("foo", r).Update(float64(47.0))
	t.Logf("registry: %v", r)
	if g := GetOrRegisterGaugeFloat64("foo", r); float64(47.0) != g.Value() {
		t.Fatal(g)
	}
}

func TestFunctionalGaugeFloat64(t *testing.T) {
	var counter float64
	fg := NewFunctionalGaugeFloat64(func() float64 {
		counter++
		return counter
	})
	fg.Value()
	fg.Value()
	if counter != 2 {
		t.Error("counter != 2")
	}
}

func TestGetOrRegisterFunctionalGaugeFloat64(t *testing.T) {
	r := NewRegistry()
	NewRegisteredFunctionalGaugeFloat64("foo", r, func() float64 { return 47 })
	if g := GetOrRegisterGaugeFloat64("foo", r); 47 != g.Value() {
		t.Fatal(g)
	}
}
