Bottleneck Defense Micro AI: code cleanup

data/ai/micro_ais/cas/ca_bottleneck_attack.lua

@@ -4,75 +4,73 @@ local H = wesnoth.require "lua/helper.lua"
 local ca_bottleneck_attack = {}
 
 function ca_bottleneck_attack:evaluation(ai, cfg, self)
-    -- All units with attacks_left and enemies next to them
-    -- This will be much easier once the 'attacks' variable is implemented
     local attackers = AH.get_units_with_attacks {
         side = wesnoth.current.side,
         { "filter_adjacent", {
             { "filter_side", { { "enemy_of", {side = wesnoth.current.side} } } }
         } }
     }
-    --print("\n\nAttackers:",#attackers)
     if (not attackers[1]) then return 0 end
 
-    -- Now loop through the attackers, and all attacks for each
-    local max_rating, best_att, best_tar, best_weapon = 0, {}, {}, -1
-    for i,a in ipairs(attackers) do
+    local max_rating, best_attacker, best_target, best_weapon = -9e99
+    for _,attacker in ipairs(attackers) do
         local targets = wesnoth.get_units {
-            { "filter_side", { {"enemy_of", {side = wesnoth.current.side} } } },
-            { "filter_adjacent", { id = a.id } }
+            { "filter_side", { { "enemy_of", { side = wesnoth.current.side } } } },
+            { "filter_adjacent", { id = attacker.id } }
         }
-        --print("  ",a.id,#targets)
 
-        for j,t in ipairs(targets) do
+        for _,target in ipairs(targets) do
             local n_weapon = 0
-            for weapon in H.child_range(a.__cfg, "attack") do
+            for weapon in H.child_range(attacker.__cfg, "attack") do
                 n_weapon = n_weapon + 1
 
-                local att_stats, def_stats = wesnoth.simulate_combat(a, n_weapon, t)
+                local att_stats, def_stats = wesnoth.simulate_combat(attacker, n_weapon, target)
 
-                local rating = 0
+                local rating
                 -- This is an acceptable attack if:
                 -- 1. There is no counter attack
                 -- 2. Probability of death is >=67% for enemy, 0% for attacker
-                if (att_stats.hp_chance[a.hitpoints] == 1)
+                if (att_stats.hp_chance[attacker.hitpoints] == 1)
                     or ((def_stats.hp_chance[0] >= 0.67) and (att_stats.hp_chance[0] == 0))
                 then
-                    rating = 1000 + t.max_hitpoints + def_stats.hp_chance[0]*100 + att_stats.average_hp - def_stats.average_hp
-                    -- if there's a chance to make the kill, unit closest to leveling up goes first, otherwise the other way around
+                    rating = target.max_hitpoints + def_stats.hp_chance[0] * 100
+                    rating = rating + att_stats.average_hp - def_stats.average_hp
+
+                    -- If there's a chance to make the kill, unit closest to leveling up goes first,
+                    -- otherwise the other way around
                     if (def_stats.hp_chance[0] >= 0.67) then
-                        rating = rating + (a.experience - a.max_experience) / 10.
+                        rating = rating + (attacker.experience - attacker.max_experience) / 10.
                     else
-                        rating = rating - (a.experience - a.max_experience) / 10.
+                        rating = rating - (attacker.experience - attacker.max_experience) / 10.
                     end
                 end
-                --print(a.id, t.id,weapon.name, rating)
-                if rating > max_rating then
-                    max_rating, best_att, best_tar, best_weapon = rating, a, t, n_weapon
+
+                if rating and (rating > max_rating) then
+                    max_rating = rating
+                    best_attacker, best_target, best_weapon = attacker, target, n_weapon
                 end
             end
         end
     end
-    --print("Best attack:",best_att.id, best_tar.id, max_rating, best_weapon)
 
-    if max_rating == 0 then
+    if (not best_attacker) then
         -- In this case we take attacks away from all units
-        -- This is done so that the RCA AI CAs can be kept in place
         self.data.BD_bottleneck_attacks_done = true
     else
         self.data.BD_bottleneck_attacks_done = false
-        self.data.BD_attacker = best_att
-        self.data.BD_target = best_tar
+        self.data.BD_attacker = best_attacker
+        self.data.BD_target = best_target
         self.data.BD_weapon = best_weapon
     end
+
     return cfg.ca_score
 end
 
 function ca_bottleneck_attack:execution(ai, cfg, self)
     if self.data.BD_bottleneck_attacks_done then
         local units = AH.get_units_with_attacks { side = wesnoth.current.side }
-        for i,u in ipairs(units) do
-            AH.checked_stopunit_attacks(ai, u)
+        for _,unit in ipairs(units) do
+            AH.checked_stopunit_attacks(ai, unit)
         end
     else
         AH.checked_attack(ai, self.data.BD_attacker, self.data.BD_target, self.data.BD_weapon)