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

export default function(Component) {
  return class Inventory extends Component {
    insertMany(entities) {
      for (const [id, {slotChange}] of entities) {
        if (slotChange) {
          const {slots} = this.get(id);
          for (const slotIndex in slotChange) {
            if (false === slotChange[slotIndex]) {
              delete slots[slotIndex];
            }
            else {
              slots[slotIndex] = {
                ...slots[slotIndex],
                ...slotChange[slotIndex],
              };
            }
          }
        }
      }
      return super.insertMany(entities);
    }
    mergeDiff(original, update) {
      if (!update.slotChange) {
        return super.mergeDiff(original, update);
      }
      const slotChange = {
        ...original.slotChange,
      };
      for (const index in update.slotChange) {
        if (false === update.slotChange[index]) {
          slotChange[index] = false;
        }
        else {
          slotChange[index] = {
            ...slotChange[index],
            ...update.slotChange[index],
          };
        }
      }
      return {slotChange};
    }
    instanceFromSchema() {
      const Instance = super.instanceFromSchema();
      const Component = this;
      Instance.prototype.item = async function (slot) {
        const {slots} = this;
        if (!(slot in slots)) {
          return undefined;
        }
        const json = await (
          fetch([slots[slot].source, 'item.json'].join('/'))
            .then((response) => (response.ok ? response.json() : {}))
        );
        const item = {
          ...slots[slot],
          ...json,
        };
        const instance = this;
        const proxy = new Proxy(item, {
          set(target, property, value) {
            slots[slot][property] = value;
            if ('qty' === property && value <= 0) {
              Component.markChange(instance.entity, 'slotChange', {[slot]: false});
              delete slots[slot];
            }
            else {
              Component.markChange(instance.entity, 'slotChange', {[slot]: {[property]: value}});
            }
            return true;
          },
        });
        return proxy;
      };
      Instance.prototype.swapSlots = function(l, r) {
        const {slots} = this;
        const tmp = slots[l];
        const change = {};
        if (slots[r]) {
          change[l] = slots[l] = slots[r];
        }
        else {
          change[l] = false;
          delete slots[l];
        }
        if (tmp) {
          change[r] = slots[r] = tmp;
        }
        else {
          change[r] = false;
          delete slots[r];
        }
        Component.markChange(this.entity, 'slotChange', change);
      };
      return Instance;
    }
    static schema = new Schema({
      type: 'object',
      properties: {
        slots: {
          type: 'map',
          value: {
            type: 'object',
            properties: {
              quantity: {type: 'uint16'},
              source: {type: 'string'},
            },
          },
        },
      },
    });
  }
}