try to fix mobs stuck forever in water

mods/ENTITIES/mcl_mobs/api.lua

@@ -300,6 +300,11 @@ end
 -- Returns true is node can deal damage to self
 local is_node_dangerous = function(self, nodename)
 	local nn = nodename
+	if self.fly then
+		if not minetest.get_item_group(nn, self.fly_in) then
+			return true
+		end
+	end
 	if self.water_damage > 0 then
 		if minetest.get_item_group(nn, "water") ~= 0 then
 			return true
@@ -317,9 +322,12 @@ local is_node_dangerous = function(self, nodename)
 	end
 	if minetest.registered_nodes[nn].drowning > 0 then
 		if self.breath_max ~= -1 then
+			-- check if the mob is water-breathing _and_ the block is water; only return true if neither is the case
+			if not self.breathes_in_water and minetest.get_item_group(nn, "water") ~= 0 then
 				return true
 			end
 		end
+	end
 	if minetest.registered_nodes[nn].damage_per_second > 0 then
 		return true
 	end
@@ -2013,8 +2021,12 @@ local do_states = function(self, dtime)
 		if (self.water_damage > 0
 		and self.lava_damage > 0)
 		or self.breath_max ~= -1 then
-
+			-- water-breathing mobs don't have to avoid water, but air
+			if self.breathes_in_water then
+				lp = minetest.find_node_near(s, 1, {"air", "group:lava"})
+			else 
 				lp = minetest.find_node_near(s, 1, {"group:water", "group:lava"})
+			end
 
 		elseif self.water_damage > 0 then
 
@@ -2032,35 +2044,61 @@ local do_states = function(self, dtime)
 
 		local is_in_danger = false
 		if lp then
-			-- If mob in or on dangerous block, look for land
-			if (is_node_dangerous(self, self.standing_in) or
+			-- minetest.log(self.name .. ": " .. minetest.get_node(lp).name)
+			-- if mob is flying, only check the block it is inside
+			if self.fly then 
+				if is_node_dangerous(self, self.standing_in) then
+					is_in_danger = true
+				end
+			elseif not self.fly and (is_node_dangerous(self, self.standing_in) or
 				is_node_dangerous(self, self.standing_on)) then
 				is_in_danger = true
-
+			end
+			-- If mob in or on dangerous block, look for land
+			if is_in_danger then
+				-- minetest.log(self.name .. " is in/on dangerous node " .. self.standing_on .. " or " .. self.standing_in)
 				lp = minetest.find_node_near(s, 5, {"group:solid"})
 
 				-- did we find land?
 				if lp then
 					local nn = minetest.get_node(lp).name
-					if is_node_dangerous(self, nn) then
-						-- is the chosen destination safe? Retry if not (max 10 iterations)
+					-- minetest.log(self.name .. " found land: " .. nn)
+
+					-- is the chosen destination safe and walkable? Retry if not (max 10 iterations)
 					local i = 0
-						while i < 10 do
+					local max_i = 10
+					while i < max_i do
+						local node_above_ok = false
 						if lp then
 							nn = minetest.get_node(lp).name
-								minetest.log("Found solid block: " .. nn)
-								if not is_node_dangerous(self, nn) then break
+							local pos = {x = lp.x, y = lp.y + 2, z = lp.z}
+							local node_above = minetest.get_node(pos)
+							local nn_above = node_above.name
+
+							minetest.log("Node: " .. nn .. " Node above: " .. nn_above)
+							if self.breath_max ~= -1 then
+								-- water-breathing mobs don't have to avoid water, but air
+								if self.breathes_in_water and minetest.get_item_group(nn_above, "water") then
+									node_above_ok = true
+								elseif not self.breathes_in_water and nn_above == "air"  then
+									node_above_ok = true
+								end
+							else
+								node_above_ok = true
+							end
+							if not is_node_dangerous(self, nn) and minetest.registered_nodes[nn].walkable and node_above_ok then 
+								minetest.log(self.name .. ": Found solid block: " .. nn .. " Above: " .. nn_above)
+								break
 						end
 						-- look for solid node 5 blocks around the mob's position
-							elseif i < 5 then
+						elseif i < (max_i / 2) then
 							lp = minetest.find_node_near(s, 5, {"group:solid"})
 						-- after 5 iterations double search radius
-							elseif i < 10 then
+						elseif i < max_i then
 							lp = minetest.find_node_near(s, 10, {"group:solid"})
 						end
 						i = i + 1
 					end
-					end
 
 					local vec = {
 						x = lp.x - s.x,