boilerplate

module/documents/item.mjs

@@ -0,0 +1,68 @@
+/**
+ * Extend the basic Item with some very simple modifications.
+ * @extends {Item}
+ */
+export class TotemItem extends Item {
+  /**
+   * Augment the basic Item data model with additional dynamic data.
+   */
+  prepareData() {
+    // As with the actor class, items are documents that can have their data
+    // preparation methods overridden (such as prepareBaseData()).
+    super.prepareData();
+  }
+
+  /**
+   * Prepare a data object which is passed to any Roll formulas which are created related to this Item
+   * @private
+   */
+   getRollData() {
+    // If present, return the actor's roll data.
+    if ( !this.actor ) return null;
+    const rollData = this.actor.getRollData();
+    // Grab the item's system data as well.
+    rollData.item = foundry.utils.deepClone(this.system);
+
+    return rollData;
+  }
+
+  /**
+   * Handle clickable rolls.
+   * @param {Event} event   The originating click event
+   * @private
+   */
+  async roll() {
+    const item = this;
+
+    // Initialize chat data.
+    const speaker = ChatMessage.getSpeaker({ actor: this.actor });
+    const rollMode = game.settings.get('core', 'rollMode');
+    const label = `[${item.type}] ${item.name}`;
+
+    // If there's no roll data, send a chat message.
+    if (!this.system.formula) {
+      ChatMessage.create({
+        speaker: speaker,
+        rollMode: rollMode,
+        flavor: label,
+        content: item.system.description ?? ''
+      });
+    }
+    // Otherwise, create a roll and send a chat message from it.
+    else {
+      // Retrieve roll data.
+      const rollData = this.getRollData();
+
+      // Invoke the roll and submit it to chat.
+      const roll = new Roll(rollData.item.formula, rollData);
+      // If you need to store the value first, uncomment the next line.
+      // let result = await roll.roll({async: true});
+      roll.toMessage({
+        speaker: speaker,
+        rollMode: rollMode,
+        flavor: label,
+      });
+      return roll;
+    }
+  }
+}