cleanup of scr_damage in DELTARUNE Chapter 2 for reference

damage.js

function selectRandomTarget()
{
    if (!partyCharacter[0].targetable && !partyCharacter[1].targetable && !partyCharacter[2].targetable)
        return 3
    var _target = choose(0, 1, 2)
    while (!partyCharacter[_target].targetable)
        _target = choose(0, 1, 2)
    return _target
}

function calcDamage(_damage, _target)
{
    var _tempDamage = _damage
    for (var i = 0; i < _target.def; i++)
    {
        if (_tempDamage > (_target.maxHp / 5))
            _tempDamage -= 3
        else if (_tempDamage > (_target.maxHp / 8))
            _tempDamage -= 2
        else
            _tempDamage -= 1
    }
    return Math.max(_tempDamage, 1)
}
function calcDamageOld(_damage, _target)
{
    return Math.ceil(_damage - (_target.def * 3))
}

function calcElementDamageReductionFactor(_element, _char)
{
    if (_element == 0)
        return 1
    var _reduction = 1
    for (var i = 1; i < 3; i++)
    {
        var _curItem = itemsWithElements[_char][i]
        if (_curItem.element != 0)
        {
            if (_curItem.element == 10)
                _reduction -= _curItem.elementReduceAmount
            else if (_curItem.element == 9 && (_element == 2 || _element == 8))
                _reduction -= _curItem.elementReduceAmount
            else if (_curItem.element == _element)
                _reduction -= _curItem.elementReduceAmount
        }
    }
    return Math.max(0.25, _reduction)
}

// target is the party slot to damage
// 3 damages all members, 4 selects a random member
function damage(damage, target, element = 0)
{
    var _target = target
    if (_target < 3 && partyCharacter[_target].hp <= 0)
        _target = selectRandomTarget()
    if (_target == 4)
    {
        _target = selectRandomTarget()
        var _partyAvgHp = 0
        var _totalHp = 0
        var _totalMaxHp = 0
        for (var i = 0; i < 3; i++)
        {
            if (partyCharacter[i] > 0)
            {
                _totalHp += partyCharacter[i].hp
                _totalMaxHp += partyCharacter[i].maxHp
            }
        }
        if (_totalHp > 0 && _totalMaxHp > 0)
            _partyAvgHp = Math.floor(_totalHp / _totalMaxHp)
        if ((partyCharacter[_target].hp / partyCharacter[_target].maxHp) < (_partyAvgHp / 2))
            _target = selectRandomTarget()
        if ((partyCharacter[_target].hp / partyCharacter[_target].maxHp) < (_partyAvgHp / 2))
            _target = selectRandomTarget()
        if (_target == 0 && (partyCharacter[_target].hp / partyCharacter[_target].maxHp) < 0.35)
            _target = selectRandomTarget()
    }
    var _targetChar = 3
    var _tempDamage = damage
    var oldCalculationAlgo = false
    if (_target < 3)
    {
        _targetChar = partyCharacter[_target]
        if (oldCalculationAlgo)
            _tempDamage = calcDamageOld(_tempDamage, _targetChar)
        else
            _tempDamage = calcDamage(_tempDamage, _targetChar)
        if (_targetChar.action == ACTION_DEFEND)
            _tempDamage = Math.ceil(_tempDamage * 2 / 3)
        _tempDamage = Math.max(1, Math.ceil(_tempDamage * calcElementDamageReductionFactor(element, _targetChar)))
        if (_targetChar.hp <= 0)
        {
            _tempDamage = Math.round(_tempDamage / 4)
            _targetChar.hurt(_tempDamage)
        }
        else
        {
            _targetChar.hurt(_tempDamage)
            if (_targetChar.hp <= 0)
                _targetChar.hp = Math.round(-(_targetChar.maxHp) / 2)
        }
    }
    else if (_target == 3)
    {
        for (var i = 0; i < 3; i++)
        {
            _targetChar = partyCharacter[i]
            if (_targetChar.hp >= 0)
            {
                if (oldCalculationAlgo)
                    _tempDamage = calcDamageOld(_tempDamage, _targetChar)
                else
                    _tempDamage = calcDamage(_tempDamage, _targetChar)
                _tempDamage = Math.ceil(_tempDamage * calcElementDamageReductionFactor(element, _targetChar))
                if (_targetChar.action == ACTION_DEFEND)
                    _tempDamage = Math.ceil(_tempDamage * 3 / 4)
                _targetChar.hurt(_tempDamage)
                if (_targetChar.hp <= 0)
                    _targetChar.hp = Math.round(-(partyCharacter[0].maxHp) / 2) // ??? selects kris' hp
            }
        }
    }
}