Mock Battle

So now that we have all of our classes and subclasses set up we should take a look at using them. We'll do this through code, and observe the output in the Corona console.

If you want to follow along, you can download the demo project which contains the "battle" code as well as all the classes in a Corona project.

Here I'm just going to point out some important parts of the code. You can view the full code further below.

Code Setup

At the start of the file we localize a few string methods for output. You might notice we don't need to require the Classy OOP plugin here. As a matter of fact we've only needed the plugin in a couple of the code class pages.

Classes

Characters

Now we bring in the Character classes that we created:

...

local Mage    = require("classes.Mage")
local Warrior = require("classes.Warrior")

...

You should notice that we don't need to bring in the base Character class file. We only need the subclasses, as they already have references to the base Character class.

Weapons

We follow up with the Weapon classes:

...

local Wand    = require("classes.Wand")
local Melee   = require("classes.Melee")

...

Again, we don't need the base Weapon class file. We only need the subclasses.

Instances

Weapons

Now let's create our weapon instances. We are doing this first so that we can "equip" them on our upcoming character instances. We could of course equip them after the fact using the character class setWeapon method, but this is just as well.

...

local sword = Melee:new('Titan Blade', 'sword', 30)
local axe   = Melee:new('Gilded Axe', 'battle axe', 50)
local wand  = Wand:new('Enchanted Stick', 'wand', 10)

...

Above we are creating two Melee class weapons, and one Wand. The Weapon base class takes a name, isType, and attack argument, which we pass for each of the instaces we created.

We now have three weapon instances that we can "equip" on our characters.

Characters

Building the character instances is very much the same as our weapons:

...

local hero  = Warrior:new('Thundar', 'warrior', 100, 100, sword)
local boss  = Warrior:new('Azarak', 'warrior', 200, 200, axe)
local mage  = Mage:new('Chalice', 'mage', 60, 60, wand, 100, 100)

...

Above we have created two warriors, one a hero and the other a boss (baddie). We also have a mage along with us.

The Warrior class needs a name, isType, health, maxHealth, and weapon argument passed to it. The Mage is a special subclass that also takes a mana and maxMana argument along with the others.

As you can see, we pass the previously generated weapon instances directly to the character instances.

Output Methods

After our charactes and weapons there are a handful of utility methods to help print out the "battle" status as it takes place. These should be fairly self-explanatory.

There is one method that should be pointed out:

...

local function attackStatus(attacker, attacked)
  local weapon = attacker:getWeapon()

  psf("%s attacks %s with %s for %d HP", 
  attacker:getName(),
  attacked:getName(),
  weapon:getName(),
  weapon:getAttack())

  --Specialized for Mage type
  if attacker:instanceOf(Mage) then
    psf("%s now has %d MP", 
    attacker:getName(),
    attacker:getMana())
  end
end

...

In the method above, we are getting the "attack" status after an attack method has been called in battle. Since a Mage has an extra mana property, we need to treat it a little differently. We can use the instanceOf method to do a type check (in this case for a Mage type) and then add our logic as needed. In this case printing out the remaining mana.

Battle Methods

The "battle" itself takes place in a couple of rounds. We actually only use two methods through the entire thing, those being attack and heal.

The majority of the methods are used to print out the results after each method is called.

attack

The default attack method is defined in our base Character class. It looks like this:

...

function Character:attack(character)
  character:hit(self.weapon:getAttack())
end

...

The method is called like so:

<attacker>:attack(<attacked>)

In our "battle" code it ends up like this, depending on whose doing the attacking:

...

hero:attack(boss)

...

The Mage character class is a little different to facilitate its mana property. The default attack method is overidden, and looks like so in the Mage class:

...

--override parent method
function Mage:attack(character)
  local weapon = self:getWeapon()
  self:useMana(weapon:getManaCost())

  --Call parent attack method
  Mage.super.attack(self, character)
end

...

In the overridden method, we want to deplete some of the mages mana, and then we call the Mage.super.attack method, which does the rest of the work of the default Character attack method.

The attack method is still used the same in the "battle" code:

...

mage:attack(boss)

...

heal

The heal method is defined in the base Character class, and looks like so:

...

function Character:heal(amount)
  amount = self:getHealth() + amount
  self:setHealth(math.min(amount, self:getMaxHealth()))
end

...

We simply call this method in the "battle" on the instance we want to heal, along with the amount to heal with:

...

mage:heal(20)

...

The "Battle Code

If you'd like to run the full project in Corona, and see the output, download the demo project. The main "battle" code is shown below:

--#############################################################################
--# Classy OOP - Mock Battle Demo
--# (c)2018 C. Byerley (develephant)
--#############################################################################
local sf = string.format
local rep = string.rep
--#############################################################################
--# Character + Weapon Classes
--#############################################################################
local Mage    = require("classes.Mage")
local Warrior = require("classes.Warrior")
local Wand    = require("classes.Wand")
local Melee   = require("classes.Melee")
--#############################################################################
--# Create Weapon Instances
--#############################################################################
local sword = Melee:new('Titan Blade', 'sword', 30)
local axe   = Melee:new('Gilded Axe', 'battle axe', 50)
local wand  = Wand:new('Enchanted Stick', 'wand', 10)
--#############################################################################
--# Create Character Instances
--#############################################################################
local hero  = Warrior:new('Thundar', 'warrior', 100, 100, sword)
local boss  = Warrior:new('Azarak', 'warrior', 200, 200, axe)
local mage  = Mage:new('Chalice', 'mage', 60, 60, wand, 100, 100)
--#############################################################################
--# Battle Messaging / Utilities
--#############################################################################
local psf = function(str, ...) print(sf(str, ...)) end
local pblock = function(str)
  print(rep("#", 80))
  print("# "..str)
  print(rep("#", 80))
end

local function warriorPresence(warrior)
  psf("The %s %s has appeared with %d HP", 
  warrior:getType(), 
  warrior:getName(), 
  warrior:getHealth())

  local weapon = warrior:getWeapon()

  psf("%s welds %s, a %s with %d attack", 
  warrior:getName(),
  weapon:getName(), 
  weapon:getType(), 
  weapon:getAttack())
end

local function magePresence(mage)
  psf("The %s %s has appeared with %d HP and %d MP", 
  mage:getType(), 
  mage:getName(), 
  mage:getHealth(),
  mage:getMana())

  local weapon = mage:getWeapon()

  psf("%s welds %s, a %s with %d attack", 
  mage:getName(),
  weapon:getName(), 
  weapon:getType(), 
  weapon:getAttack())
end

local function attackStatus(attacker, attacked)
  local weapon = attacker:getWeapon()

  psf("%s attacks %s with %s for %d HP", 
  attacker:getName(),
  attacked:getName(),
  weapon:getName(),
  weapon:getAttack())

  --Specialized for Mage type
  if attacker:instanceOf(Mage) then
    psf("%s now has %d MP", 
    attacker:getName(),
    attacker:getMana())
  end
end

local function healStatus(character, amount)
  psf("%s heals for %d HP, now has %d HP.", 
  character:getName(),
  amount,
  character:getHealth())
end

local function isDead(character)
  if character:isDead() then
    psf("%s has been killed!", character:getName())
  end
end

local function healthStatus(character)
  psf("%s now has %d HP", 
  character:getName(),
  character:getHealth())

  isDead(character)
end

pblock("Classy OOP - Mock Battle Demo")

--#############################################################################
--# Battle Start Introductions
--#############################################################################
pblock("Battle Start")

--# Hero (warrior)
warriorPresence(hero)
--# Mage
magePresence(mage)
--# Boss (warrior)
warriorPresence(boss)

--#############################################################################
--# Attack Round One
--#############################################################################
pblock("Round One")

--# Mage attacks Boss
mage:attack(boss)
attackStatus(mage, boss)
healthStatus(boss)

--# Hero attacks Boss
hero:attack(boss)
attackStatus(hero, boss)
healthStatus(boss)

--# Boss attacks Mage
boss:attack(mage)
attackStatus(boss, mage)
healthStatus(mage)

--# Boss attacks Hero
boss:attack(hero)
attackStatus(boss, hero)
healthStatus(hero)

--#############################################################################
--# Attack Round Two
--#############################################################################
pblock("Round Two")

--# Mage attacks Boss
mage:attack(boss)
attackStatus(mage, boss)
healthStatus(boss)

--# Heal Mage
mage:heal(20)
healStatus(mage, 20)

--# Hero attacks Boss
hero:attack(boss)
attackStatus(hero, boss)
healthStatus(boss)

--# Boss attacks Hero
boss:attack(hero)
attackStatus(boss, hero)
healthStatus(hero)

--# Boss attacks Mage
boss:attack(mage)
attackStatus(boss, mage)
healthStatus(mage)

pblock("Battle Done")

--#############################################################################
--# UI
--#############################################################################
display.newText({
  text = "See console for demo output.",
  x = display.contentCenterX,
  y = display.contentCenterY,
  font = native.systemFontBold
})