fvtt-oath-hammer/module/applications/defense-dialog.mjs

/**
 * Defense roll dialog.
 *
 * Pool = governing attribute (Agility default; Might option for melee) + Defense skill
 *   + armorPenalty (auto from equipped armor, always ≤ 0)
 *   + parryBonus / blockBonus (from equipped weapon traits)
 *   + manual bonus
 *
 * Parry trait on equipped weapon → red dice (3+) vs melee; +1 if two Parry weapons
 * Block  trait on equipped weapon → red dice (3+) vs ranged; +1 to ranged defense
 */
export default class OathHammerDefenseDialog {

  static async prompt(actor) {
    const actorSys = actor.system

    // ── Attributes & skill ──────────────────────────────────────────────
    const agiRank     = actorSys.attributes.agility.rank
    const mightRank   = actorSys.attributes.might.rank
    const defRank     = actorSys.skills.defense.rank

    // ── Equipped weapons ────────────────────────────────────────────────
    const equipped = actor.items.filter(i => i.type === "weapon" && i.system.equipped)
    const parryCount = equipped.filter(w => w.system.traits?.has?.("parry") || [...(w.system.traits ?? [])].includes("parry")).length
    const blockCount = equipped.filter(w => w.system.traits?.has?.("block") || [...(w.system.traits ?? [])].includes("block")).length

    // ── Equipped armor penalty (sum) ────────────────────────────────────
    const armorPenalty = actor.items
      .filter(i => i.type === "armor" && i.system.equipped)
      .reduce((sum, a) => sum + (a.system.penalty ?? 0), 0)

    // ── Build option lists ───────────────────────────────────────────────
    const attackTypeOptions = [
      { value: "melee",  label: game.i18n.localize("OATHHAMMER.Dialog.DefenseMelee"),  selected: true },
      { value: "ranged", label: game.i18n.localize("OATHHAMMER.Dialog.DefenseRanged"), selected: false },
    ]

    const attrOptions = [
      { value: "agility", label: `${game.i18n.localize("OATHHAMMER.Attribute.Agility")} (${agiRank})`,  selected: true },
      { value: "might",   label: `${game.i18n.localize("OATHHAMMER.Attribute.Might")} (${mightRank})`,   selected: false },
    ]

    const bonusOptions = Array.from({ length: 13 }, (_, i) => {
      const v = i - 6
      return { value: v, label: v > 0 ? `+${v}` : String(v), selected: v === 0 }
    })

    const rollModes = foundry.utils.duplicate(CONFIG.Dice.rollModes)

    const context = {
      actorName:      actor.name,
      agiRank,
      mightRank,
      defRank,
      parryCount,
      blockCount,
      armorPenalty,
      attackTypeOptions,
      attrOptions,
      bonusOptions,
      rollModes,
      visibility: game.settings.get("core", "rollMode"),
    }

    const content = await foundry.applications.handlebars.renderTemplate(
      "systems/fvtt-oath-hammer/templates/defense-roll-dialog.hbs",
      context
    )

    const result = await foundry.applications.api.DialogV2.wait({
      window:      { title: game.i18n.format("OATHHAMMER.Dialog.DefenseTitle", { actor: actor.name }), resizable: true },
      classes:     ["fvtt-oath-hammer"],
      position:    { width: 420 },
      content,
      rejectClose: false,
      buttons: [{
        label:    game.i18n.localize("OATHHAMMER.Dialog.RollDefense"),
        callback: (_ev, btn) => Object.fromEntries(
          [...btn.form.elements].filter(e => e.name).map(e => [e.name, e.value])
        ),
      }],
    })

    if (!result) return null

    const attackType  = result.attackType ?? "melee"
    const attrChoice  = result.attribute  ?? "agility"
    const attrRank    = attrChoice === "might" ? mightRank : agiRank
    const bonus       = parseInt(result.bonus) || 0

    // Determine red dice and trait bonus from equipped weapons
    let redDice    = false
    let traitBonus = 0
    if (attackType === "melee" && parryCount > 0) {
      redDice    = true
      if (parryCount >= 2) traitBonus = 1
    } else if (attackType === "ranged" && blockCount > 0) {
      redDice    = true
      traitBonus = 1
    }

    return {
      attackType,
      attrRank,
      attrChoice,
      redDice,
      traitBonus,
      armorPenalty,
      bonus,
      visibility: result.visibility ?? game.settings.get("core", "rollMode"),
    }
  }
}