v2.1.0: combo strike now has a visible buff icon

core/src/main/assets/messages/items/items.properties

@@ -1680,6 +1680,8 @@ items.weapon.melee.sai.stats_desc=This is a very fast weapon.
 items.weapon.melee.sai.ability_name=combo strike
 items.weapon.melee.sai.ability_desc=The Duelist can perform a _combo strike_ with sai. This attack is guaranteed to hit and deals +35% damage for each time the Duelist has already successfully attacked with melee or thrown weapons in the last 5 turns.
 items.weapon.melee.sai.desc=Two thin blades meant to be wielded in one hand each. Excellent for tearing down enemies with a flurry of cuts.
+items.weapon.melee.sai$combostriketracker.name=combo strike
+items.weapon.melee.sai$combostriketracker.desc=The duelist is building combo that can be used to increase the damage of the combo strike ability. Each strike made with a melee or thrown weapon in the last 5 turns will count.\n\nRecent hits: %d.
 
 items.weapon.melee.scimitar.name=scimitar
 items.weapon.melee.scimitar.stats_desc=This is a rather fast weapon.

core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/actors/hero/Hero.java

@@ -458,7 +458,7 @@ public class Hero extends Char {
 		}
 
 		if (hit && heroClass == HeroClass.DUELIST && wasEnemy){
-			Buff.append( this, Sai.ComboStrikeTracker.class, Sai.ComboStrikeTracker.DURATION);
+			Buff.append( this, Sai.ComboStrikeTracker.class).addHit();
 		}
 
 		return hit;
@@ -2023,7 +2023,7 @@ public class Hero extends Char {
 		}
 
 		if (hit && heroClass == HeroClass.DUELIST && wasEnemy){
-			Buff.append( this, Sai.ComboStrikeTracker.class, Sai.ComboStrikeTracker.DURATION);
+			Buff.affect( this, Sai.ComboStrikeTracker.class).addHit();
 		}
 
 		RingOfForce.BrawlersStance brawlStance = buff(RingOfForce.BrawlersStance.class);

core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/items/weapon/melee/Sai.java

@@ -32,8 +32,10 @@ import com.shatteredpixel.shatteredpixeldungeon.actors.hero.Hero;
 import com.shatteredpixel.shatteredpixeldungeon.messages.Messages;
 import com.shatteredpixel.shatteredpixeldungeon.sprites.ItemSpriteSheet;
 import com.shatteredpixel.shatteredpixeldungeon.ui.AttackIndicator;
+import com.shatteredpixel.shatteredpixeldungeon.ui.BuffIndicator;
 import com.shatteredpixel.shatteredpixeldungeon.utils.GLog;
 import com.watabou.noosa.audio.Sample;
+import com.watabou.utils.Bundle;
 import com.watabou.utils.Callback;
 
 import java.util.HashSet;
@@ -90,10 +92,11 @@ public class Sai extends MeleeWeapon {
 				wep.beforeAbilityUsed(hero);
 				AttackIndicator.target(enemy);
 
-				HashSet<ComboStrikeTracker> buffs = hero.buffs(ComboStrikeTracker.class);
-				int recentHits = buffs.size();
-				for (Buff b : buffs){
-					b.detach();
+				int recentHits = 0;
+				ComboStrikeTracker buff = hero.buff(ComboStrikeTracker.class);
+				if (buff != null){
+					recentHits = buff.totalHits();
+					buff.detach();
 				}
 
 				boolean hit = hero.attack(enemy, 1f + boostPerHit*recentHits, 0, Char.INFINITE_ACCURACY);
@@ -112,10 +115,89 @@ public class Sai extends MeleeWeapon {
 		});
 	}
 
-	public static class ComboStrikeTracker extends FlavourBuff{
+	public static class ComboStrikeTracker extends Buff {
 
-		public static float DURATION = 5f;
+		{
+			type = buffType.POSITIVE;
+		}
 
+		public static int DURATION = 6; //to account for the turn the attack is made in
+		public int[] hits = new int[DURATION];
+
+		@Override
+		public int icon() {
+			//pre-v2.1 saves
+			if (totalHits() == 0) return BuffIndicator.NONE;
+
+			if (Dungeon.hero.belongings.weapon() instanceof Gloves
+					|| Dungeon.hero.belongings.weapon() instanceof Sai
+					|| Dungeon.hero.belongings.weapon() instanceof Gauntlet
+					|| Dungeon.hero.belongings.secondWep() instanceof Gloves
+					|| Dungeon.hero.belongings.secondWep() instanceof Sai
+					|| Dungeon.hero.belongings.secondWep() instanceof Gauntlet) {
+				return BuffIndicator.DUEL_COMBO;
+			} else {
+				return BuffIndicator.NONE;
+			}
+		}
+
+		@Override
+		public boolean act() {
+
+			//shuffle all hits down one turn
+			for (int i = 0; i < DURATION; i++){
+				if (i == DURATION-1){
+					hits[i] = 0;
+				} else {
+					hits[i] =  hits[i+1];
+				}
+			}
+
+			if (totalHits() == 0){
+				detach();
+			}
+
+			spend(TICK);
+			return true;
+		}
+
+		public void addHit(){
+			hits[DURATION-1]++;
+		}
+
+		public int totalHits(){
+			int sum = 0;
+			for (int i = 0; i < DURATION; i++){
+				sum += hits[i];
+			}
+			return sum;
+		}
+
+		@Override
+		public String iconTextDisplay() {
+			return Integer.toString(totalHits());
+		}
+
+		@Override
+		public String desc() {
+			return Messages.get(this, "desc", totalHits());
+		}
+
+		public static String RECENT_HITS = "recent_hits";
+
+		@Override
+		public void storeInBundle(Bundle bundle) {
+			super.storeInBundle(bundle);
+			bundle.put(RECENT_HITS, hits);
+		}
+
+		@Override
+		public void restoreFromBundle(Bundle bundle) {
+			super.restoreFromBundle(bundle);
+			if (bundle.contains(RECENT_HITS)) {
+				hits = bundle.getIntArray(RECENT_HITS);
+			}
+		}
 	}
 
 }

core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/ui/BuffIndicator.java

@@ -120,6 +120,7 @@ public class BuffIndicator extends Component {
 	public static final int DUEL_XBOW   = 66;
 	public static final int CHALLENGE   = 67;
 	public static final int MONK_ENERGY = 68;
+	public static final int DUEL_COMBO  = 69;
 
 	public static final int SIZE_SMALL  = 7;
 	public static final int SIZE_LARGE  = 16;