Fix Blood DK Legacy Rotation Opener Usage of Blood Tap with new 4pc cooldown consideration

sim/deathknight/tank/openers.go

@@ -1,12 +1,17 @@
 package tank
 
 import (
+	"github.com/wowsims/wotlk/sim/core/proto"
+	"slices"
 	"time"
 
 	"github.com/wowsims/wotlk/sim/core"
 	"github.com/wowsims/wotlk/sim/deathknight"
 )
 
+const threatOpenerCastsBeforeBloodTap = 2
+const normalOpenerCastsBeforeBloodTap = 3
+
 func (dk *TankDeathknight) TankRA_BloodSpell(sim *core.Simulation, target *core.Unit, s *deathknight.Sequence) time.Duration {
 	casted := dk.BloodSpell.Cast(sim, target)
 	advance := dk.LastOutcome.Matches(core.OutcomeLanded)
@@ -33,7 +38,38 @@ func (dk *TankDeathknight) TankRA_IT(sim *core.Simulation, target *core.Unit, s
 	return -1
 }
 
+func shouldUseBloodTapInOpener(dk *TankDeathknight) bool {
+	bloodTapDefensiveCd := dk.GetMajorCooldown(dk.BloodTap.ActionID)
+	if bloodTapDefensiveCd != nil {
+		timings := bloodTapDefensiveCd.GetTimings()
+		slices.Sort(timings)
+		if len(timings) == 0 ||
+			(len(timings) > 0 && timings[0] <
+				dk.BloodTap.CD.Duration+getPlannedOpenerBloodTapUsageTime(dk)) {
+			return false
+		} else {
+			return true
+		}
+	}
+	return true
+}
+
+func getPlannedOpenerBloodTapUsageTime(dk *TankDeathknight) time.Duration {
+	if dk.Rotation.Opener == proto.TankDeathknight_Rotation_Threat {
+		return threatOpenerCastsBeforeBloodTap * core.GCDDefault
+	}
+	return normalOpenerCastsBeforeBloodTap * core.GCDDefault
+}
+
 func (dk *TankDeathknight) setupTankRegularERWOpener() {
+	if shouldUseBloodTapInOpener(dk) {
+		dk.setupTankRegularERWOpenerWithBloodTap()
+	} else {
+		dk.setupTankRegularERWOpenerWithoutBloodTap()
+	}
+}
+
+func (dk *TankDeathknight) setupTankRegularERWOpenerWithBloodTap() {
 	dk.RotationSequence.
 		NewAction(dk.TankRA_IT).
 		NewAction(dk.RotationActionCallback_PS).
@@ -50,7 +86,30 @@ func (dk *TankDeathknight) setupTankRegularERWOpener() {
 		NewAction(dk.TankRA_FuSpell)
 }
 
+func (dk *TankDeathknight) setupTankRegularERWOpenerWithoutBloodTap() {
+	dk.RotationSequence.
+		NewAction(dk.TankRA_IT).
+		NewAction(dk.RotationActionCallback_PS).
+		NewAction(dk.TankRA_FuSpell).
+		NewAction(dk.TankRA_BloodSpell).
+		NewAction(dk.RotationActionCallback_ERW).
+		NewAction(dk.RotationActionCallback_Pesti).
+		NewAction(dk.TankRA_IT).
+		NewAction(dk.TankRA_IT).
+		NewAction(dk.TankRA_IT).
+		NewAction(dk.RotationActionCallback_RD).
+		NewAction(dk.TankRA_FuSpell)
+}
+
 func (dk *TankDeathknight) setupTankThreatERWOpener() {
+	if shouldUseBloodTapInOpener(dk) {
+		dk.setupTankThreatERWOpenerWithBloodTap()
+	} else {
+		dk.setupTankThreatERWOpenerWithoutBloodTap()
+	}
+}
+
+func (dk *TankDeathknight) setupTankThreatERWOpenerWithBloodTap() {
 	dk.RotationSequence.
 		NewAction(dk.TankRA_IT).
 		NewAction(dk.TankRA_IT).
@@ -63,3 +122,9 @@ func (dk *TankDeathknight) setupTankThreatERWOpener() {
 		NewAction(dk.RotationActionCallback_PS).
 		NewAction(dk.TankRA_BloodSpell)
 }
+
+// If maintaining GCD parity is desired, the threat opener without BT should cast DS with
+// the GCD previously allocated to the Blood Tapped IT before using ERW
+func (dk *TankDeathknight) setupTankThreatERWOpenerWithoutBloodTap() {
+	dk.setupTankRegularERWOpenerWithoutBloodTap()
+}