import type { Resource, TemplateResultOrSymbol } from "@src/tems";
import { LitElement, nothing } from "lit";

import * as rdf from "@src/rdf";
import { property } from "lit/decorators.js";

const rdfs = Object.values(rdf);

export class TemsObjectsHandler extends LitElement {
  @property({ attribute: false })
  objects?: Resource[] = [];

  hasType = (type: string, objs: Resource[] = this.objects as Resource[]) => {
    const typeValue = new Set(objs.flatMap((o) => o["@type"]));
    return typeValue.has(type);
  };

  renderTemplateWhenWith(
    requiredProperties: (string | string[])[],
    template: () => TemplateResultOrSymbol,
    objs: Resource[] = this.objects as Resource[]
  ): TemplateResultOrSymbol {
    const tester = (
      property: string | string[],
      cb: (some: string) => boolean
    ) =>
      Array.isArray(property)
        ? property.some((subProp) => cb(subProp))
        : cb(property);

    const typeProperties = requiredProperties.filter((property) =>
      tester(property, (p) => rdfs.includes(p))
    );

    if (
      typeProperties.every((property) =>
        tester(property, (p) => this.hasType(p, objs))
      )
    ) {
      return template.call(this);
    }
    return nothing;
  }
}