import { emit } from "../../shared/helpers";

/** PettyDataTable — sortable table with click-to-sort column headers. */
export class PettyDataTable extends HTMLElement {
  connectedCallback(): void {
    const headers = this.querySelectorAll<HTMLElement>("th[data-sort]");
    for (const th of headers) {
      th.setAttribute("role", "columnheader");
      th.setAttribute("aria-sort", "none");
      th.style.cursor = "pointer";
      th.addEventListener("click", this.#onHeaderClick);
    }
  }

  disconnectedCallback(): void {
    const headers = this.querySelectorAll<HTMLElement>("th[data-sort]");
    for (const th of headers) th.removeEventListener("click", this.#onHeaderClick);
  }

  #onHeaderClick = (e: Event): void => {
    const th = e.currentTarget as HTMLElement;
    const column = th.dataset.sort ?? "";
    const current = th.getAttribute("aria-sort") ?? "none";
    const next = current === "ascending" ? "descending" : "ascending";
    this.#clearSorts();
    th.setAttribute("aria-sort", next);
    th.dataset.state = next;
    this.#sortBy(th, next === "ascending" ? 1 : -1);
    emit(this, "sort", { column, direction: next });
  };

  #clearSorts(): void {
    const headers = this.querySelectorAll<HTMLElement>("th[data-sort]");
    for (const th of headers) { th.setAttribute("aria-sort", "none"); th.dataset.state = "none"; }
  }

  #sortBy(th: HTMLElement, dir: number): void {
    const tbody = this.querySelector("tbody[data-part=body]") ?? this.querySelector("tbody");
    if (!tbody) return;
    const headerRow = th.parentElement;
    if (!headerRow) return;
    const colIdx = Array.from(headerRow.children).indexOf(th);
    const rows = Array.from(tbody.querySelectorAll("tr"));
    rows.sort((a, b) => {
      const aText = a.children[colIdx]?.textContent?.trim() ?? "";
      const bText = b.children[colIdx]?.textContent?.trim() ?? "";
      const aNum = Number(aText);
      const bNum = Number(bText);
      if (!Number.isNaN(aNum) && !Number.isNaN(bNum)) return (aNum - bNum) * dir;
      return aText.localeCompare(bText) * dir;
    });
    for (const row of rows) tbody.appendChild(row);
  }
}