swade-mb-helpers/scripts/rollHelpers.js

import { log, shim } from './shim.js'

export async function preTraitRollModifiers (actor, trait, roll, modifiers, options) {
  const targets = Array.from(shim.targets)
  const token = shim.canvas.tokens.controlled.length > 0 ? shim.canvas.tokens.controlled[0] : null
  // log('ACTOR', actor)
  // log('TOKEN', token)
  // log('TRAIT', trait)
  // log('ROLL', roll)
  // log('MODIFIERS', modifiers)
  // log('OPTIONS', options)
  // log('TARGET', targets)
  if (targets.some(target => target.actor.system.status.isVulnerable)) {
    modifiers.push({ label: 'Target is Vulnerable', value: '+2', ignore: false })
  }
  if (targets.some(
    target => target.actor.effects.filter(
      e => !e.disabled && e.name.toLowerCase().includes('deflection')).length > 0)
  ) {
    modifiers.push({ label: 'Target has Deflection', value: '-2', ignore: false })
  }
  if (targets.length === 1 && token) {
    const target = targets[0]
    _addArcaneModifiers(target, modifiers)
    const scaleMod = calcScaleMod(token, target)
    if (scaleMod !== 0) {
      modifiers.push({ label: 'Scale', value: scaleMod, ignore: false })
    }
    if (trait?.type === 'skill' && trait?.system?.swid === 'fighting') {
      const gangUpBonus = calcGangup(token, target)
      if (gangUpBonus > 0) {
        modifiers.push({ label: 'Gang Up', value: gangUpBonus, ignore: false })
      }
    }
  }
}

export async function preDamageRollModifiers (actor, item, roll, modifiers, options) {
  const targets = Array.from(shim.targets)
  const token = shim.canvas.tokens.controlled.length > 0 ? shim.canvas.tokens.controlled[0] : null
  // log('ACTOR', actor)
  // log('TOKEN', token)
  // log('ITEM', item)
  // log('ROLL', roll)
  // log('MODIFIERS', modifiers)
  // log('OPTIONS', options)
  // log('TARGET', targets)
  if (targets.length === 1 && token) {
    const target = targets[0]
    _addArcaneModifiers(target, modifiers)
    const weaknesses = target.actor.items.filter(
      i => i.type === 'ability' && i.system.swid.toLowerCase().includes('weakness'))
    if (weaknesses.length > 0) {
      modifiers.push(...weaknesses.map(i => { return { label: i.name, value: '+4', ignore: true } }))
    }
    const resistances = target.actor.items.filter(
      i => i.type === 'ability' && i.system.swid.toLowerCase().includes('resistance'))
    if (resistances.length > 0) {
      modifiers.push(...resistances.map(i => { return { label: i.name, value: '-4', ignore: true } }))
    }
    if (_findItem(token.actor, 'ability', 'pack-tactics')) {
      const gangupBonus = calcGangup(token, target)
      if (gangupBonus > 0) {
        modifiers.push({ label: 'Gang Up (Pack Tactics)', value: gangupBonus, ignore: false })
      }
    }
  }
}

function _addArcaneModifiers (target, modifiers) {
  if (_findItem(target.actor, 'edge', 'improved-arcane-resistance')) {
    modifiers.push({ label: 'Arcane Resistance', value: '-4', ignore: true })
  } else if (_findItem(target.actor, 'edge', 'arcane-resistance')) {
    modifiers.push({ label: 'Arcane Resistance', value: '-2', ignore: true })
  }
  const effect = target.actor.effects.find(
    e => !e.disabled && e.name.toLowerCase().includes('arcane protection'))
  if (effect) {
    const effectName = effect.name.toLowerCase()
    const effectMod = (
      -2 +
      (effectName.includes('major') ? -2 : 0) +
      (effectName.includes('greater') ? -2 : 0)
    )
    modifiers.push({ label: 'Target Arcane Protection', value: effectMod, ignore: true })
  }
}

function withinRange (origin, target, range) {
  const ray = new Ray(origin, target)
  const distance = shim.canvas.grid.measureDistances([{ ray }], { gridSpaces: true })[0]
  const originScale = origin.actor.system.stats.scale
  const targetScale = target.actor.system.stats.scale
  range += (originScale > 0 ? originScale / 2 : 0) + (targetScale > 0 ? targetScale / 2 : 0)
  return range >= distance
}

function _findItem (actor, type, swid) {
  return actor.items.find(i => i.type === type && i.system.swid === swid)
}

function calcScaleMod (attacker, target) {
  const attackerScale = attacker.actor.system.stats.scale
  const targetScale = target.actor.system.stats.scale
  const attackerHasSwat = !!_findItem(attacker.actor, 'ability', 'swat')
  let modifier = targetScale - attackerScale
  if (attackerHasSwat && modifier < 0) {
    modifier = Math.min(modifier + 4, 0)
  }
  return modifier
}

function calcGangup (attacker, target, debug) {
  debug = (typeof debug === 'undefined') ? false : debug
  const range = 1.2
  let modifier = 0
  if (_findItem(target.actor, 'edge', 'improved-block')) {
    modifier = -2
  } else if (_findItem(target.actor, 'edge', 'block')) {
    modifier = -1
  }
  const attackerHasFormationFighter = !!(_findItem(attacker.actor, 'edge', 'formation-fighter'))

  const withinRangeOfToken = shim.canvas.tokens.placeables.filter(t =>
    t.id !== attacker.id &&
    t.id !== target.id &&
    t.actor.system.status.isStunned === false &&
    t.visible &&
    withinRange(target, t, range)
  )
  const attackerAllies = withinRangeOfToken.filter(
    t => t.document.disposition === attacker.document.disposition)
  const targetAllies = withinRangeOfToken.filter(
    t => t.document.disposition === target.document.disposition &&
    withinRange(attacker, t, range)
  )
  const attackersWithFormationFighter = attackerAllies.filter(
    t => !!_findItem(t.actor, 'edge', 'formation-fighter'))
  const attackerCount = attackerAllies.length
  const attackerFormationBonus = (
    (attackerCount > 0 && attackerHasFormationFighter ? 1 : 0) +
    attackersWithFormationFighter.length
  )
  const defenderCount = targetAllies.length
  const gangUp = Math.max(
    0,
    Math.min(
      4,
      attackerCount + attackerFormationBonus - defenderCount + modifier))
  if (debug) {
    log('GANG UP | Attacker:', attacker)
    log('GANG UP | Target:', target)
    log('GANG UP | Others within range:', withinRangeOfToken)
    log('GANG UP | Attacker Allies:', attackerCount)
    log('GANG UP | Attacker Formation Bonus:', attackerFormationBonus)
    log('GANG UP | Effective Defender Allies:', defenderCount)
    log('GANG UP | Target Block Modifier:', modifier)
    log('GANG UP | Total Bonus:', gangUp)
  }
  return gangUp
}