silphius/app/ecs-components/inventory.js

import Schema from '@/ecs/schema.js';

export default function(Component) {
  return class Inventory extends Component {
    insertMany(entities) {
      for (const [id, {slotChanged}] of entities) {
        if (slotChanged) {
          for (const slotIndex in slotChanged) {
            this.get(id).slots[slotIndex] = {
              ...this.get(id).slots[slotIndex],
              ...slotChanged[slotIndex],
            };
          }
        }
      }
      return super.insertMany(entities);
    }
    markChange(entityId, key, value) {
      if ('slotChange' === key) {
        const {index, change} = value;
        return super.markChange(entityId, key, {[index]: change});
      }
      return super.markChange(entityId, key, value);
    }
    mergeDiff(original, update) {
      if (update.slotChange) {
        if (!original.slotChange) {
          original.slotChange = {};
        }
        const merged = {};
        for (const index in update.slotChange) {
          merged[index] = {
            ...original.slotChange[index],
            ...update.slotChange[index],
          };
        }
        return {slotChanged: merged};
      }
      return super.mergeDiff(original, update);
    }
    instanceFromSchema() {
      const Instance = super.instanceFromSchema();
      const Component = this;
      Instance.prototype.item = function (slot) {
        const {slots} = this;
        const instance = this;
        for (const index in slots) {
          const item = slots[index];
          if (slot === item.slotIndex) {
            const proxy = new Proxy(item, {
              set(target, property, value) {
                target[property] = value;
                const change = {[property]: value};
                Component.markChange(instance.entity, 'slotChange', {index, change});
                return true;
              },
            });
            return proxy;
          }
        }
      };
      return Instance;
    }
    static schema = new Schema({
      type: 'object',
      properties: {
        slots: {
          type: 'array',
          subtype: {
            type: 'object',
            properties: {
              quantity: {type: 'uint16'},
              slotIndex: {type: 'uint16'},
              source: {type: 'string'},
            },
          },
        },
      },
    });
  }
}