package throttling

import (
	"time"
)

func (suite *ThrottlerTestSuite) Test_throttlerImmediateNotificationAfterInitialized() {
	value := 0
	throttler := NewThrottler[int](func(v int) {
		value = v
	}, 1.0)

	t0 := time.Now()
	v := 1
	currentTime.now = t0
	throttler.Notify(v)
	suite.Equal(v, value)
	value = 0
	// subsequent ping will not lead to a notification
	currentTime.now = t0.Add(10 * time.Second)
	throttler.Ping()
	suite.Equal(0, value)
}

func (suite *ThrottlerTestSuite) Test_TwoNotificationsInSHortSucessionSecondOneIsDeliverdWithDelay() {
	value := 0
	delayMs := 1000
	throttler := NewThrottler[int](func(v int) {
		value = v
	}, time.Duration(delayMs)*time.Millisecond)

	t0 := time.Now()
	v1 := 1
	// v2 will not be delivered, the last value in the time interval will be
	v2 := 2
	v3 := 3
	currentTime.now = t0
	throttler.Notify(v1)
	suite.Equal(v1, value)
	throttler.Notify(v2)
	throttler.Notify(v3)
	suite.Equal(v1, value)

	currentTime.now = t0.Add(time.Duration(delayMs-1) * time.Millisecond)
	throttler.Ping()
	suite.Equal(v1, value)

	currentTime.now = t0.Add(time.Duration(delayMs) * time.Millisecond)
	throttler.Ping()
	suite.Equal(v3, value)

	// another ping won't deliver the same value again.
	value = 0
	currentTime.now = t0.Add(time.Duration(delayMs) * time.Millisecond)
	throttler.Ping()
	suite.Equal(0, value)
}

func (suite *ThrottlerTestSuite) Test_DuplicateEventsIgnored() {
	value := 0
	mindelay := 1 * time.Second
	throttler := NewThrottler[int](func(v int) {
		value = v
	}, mindelay)

	t0 := time.Now()
	v := 1
	currentTime.now = t0
	throttler.Notify(v)
	suite.Equal(v, value)

	// sending the same value again will not lead to a notification
	value = 0
	currentTime.now = currentTime.now.Add(2 * mindelay)
	throttler.Notify(v)
	suite.Equal(0, value)

	// sending a different value later will lead to a new notification
	currentTime.now = currentTime.now.Add(2 * mindelay)
	v++
	throttler.Notify(v)
	suite.Equal(v, value)
}