/* =============================================================================
 * M01_MasterData_UI_Rows.ts
 * 요소 파일(인력·재료·기계·환율·요율) 표 — 한 줄 = 요소 · 이름 찾기 · 쪽 나눔 · 눌러 고침(노랑)
 * ========================================================================== */

import { createButton, el, showToast } from "@ui/ui_template_elements";
import { t as L } from "@ui/ui_template_locale";
import { fetchRows, type Row, type RowsPage } from "./M01_MasterData_Api_Fetch";
import {
  addRow,
  editRow,
  onDraftChange,
  peek,
  removeAdd,
  same,
  setAdd,
  toggleDelete,
} from "./M01_MasterData_Draft";
import {
  buildCell,
  buildPager,
  coerce,
  flatten,
  isScalar,
  show,
  withCell,
} from "./M01_MasterData_UI_Cells";

const SIZE = 50;
const FALLBACK: Row = { 열쇠: "", 이름: "", 규격: "", 단위: "", 값: null, 출처: "" };

/** 새 줄 바탕 — 본 줄과 같은 칸 · 글 칸은 "" · 수·값 칸은 null. */
function blank(sample: Row): Row {
  const out: Row = {};
  for (const [k, v] of Object.entries(sample)) {
    if (v && typeof v === "object" && !Array.isArray(v)) out[k] = blank(v as Row);
    else out[k] = typeof v === "string" && k !== "값" ? "" : null;
  }
  return out;
}

/** 돌려받은 함수 = 이 화면을 걷을 때 부를 해제. */
export function renderRows(host: HTMLElement, file: string, q: string): () => void {
  let page = 1;
  let data: RowsPage | null = null;

  const paint = (): void => {
    if (!data) return;
    const d = data;
    const draft = peek(file);
    const adds = draft?.adds ?? [];
    const cols: string[] = [];
    for (const row of [...adds, ...d.rows]) {
      for (const k of Object.keys(flatten(row))) if (!cols.includes(k)) cols.push(k);
    }
    const head = el("tr", { children: [el("th"), ...cols.map((c) => el("th", { text: c }))] });
    const body = el("tbody");

    adds.forEach((row, i) => {
      const flat = flatten(row);
      const tr = el("tr", { className: "is-new" });
      tr.append(actionCell(L("M01_RowRemove"), () => removeAdd(file, i)));
      for (const c of cols) {
        tr.append(
          buildCell(show(flat[c]), {
            changed: true,
            onEdit: (text) => setAdd(file, i, withCell(row, c, coerce(text, flat[c]))),
          }),
        );
      }
      body.append(tr);
    });

    for (const row of d.rows) {
      const key = String(row["열쇠"]);
      const cur = draft?.edits[key] ?? row;
      const deleted = draft?.deletes.includes(key) ?? false;
      const orig = flatten(row);
      const now = flatten(cur);
      const tr = el("tr");
      tr.classList.toggle("is-deleted", deleted);
      tr.append(
        actionCell(deleted ? L("M01_RowRestore") : L("M01_RowDelete"), () =>
          toggleDelete(file, d.version, key),
        ),
      );
      for (const c of cols) {
        const editable = !deleted && isScalar(orig[c]);
        tr.append(
          buildCell(show(now[c]), {
            changed: !same(now[c], orig[c]),
            onEdit: editable
              ? (text) =>
                  editRow(file, d.version, key, row, withCell(cur, c, coerce(text, orig[c])))
              : undefined,
          }),
        );
      }
      body.append(tr);
    }

    const add = createButton({ label: L("M01_RowAdd"), variant: "ghost" });
    add.addEventListener("click", () => addRow(file, d.version, blank(d.rows[0] ?? FALLBACK)));
    const empty =
      d.rows.length || adds.length
        ? []
        : [el("p", { className: "m01-master__empty", text: L("M01_NoRows") })];
    host.replaceChildren(
      el("div", {
        className: "m01-master__bar",
        children: [add, buildPager(d.total, SIZE, d.page, go)],
      }),
      el("div", {
        className: "m01-master__grid-wrap",
        children: [
          el("table", {
            className: "m01-master__grid",
            children: [el("thead", { children: [head] }), body],
          }),
        ],
      }),
      ...empty,
    );
  };

  const go = (next: number): void => {
    page = next;
    void load();
  };

  const load = async (): Promise<void> => {
    try {
      data = await fetchRows(file, page, SIZE, q);
      paint();
    } catch (error) {
      showToast(error instanceof Error ? error.message : L("M01_LoadFailed"), "error");
    }
  };

  const off = onDraftChange(paint);
  void load();
  return off;
}

function actionCell(label: string, onClick: () => void): HTMLTableCellElement {
  const button = el("button", {
    className: "m01-master__row-btn",
    text: label,
    attrs: { type: "button" },
  });
  button.addEventListener("click", onClick);
  return el("td", { children: [button] });
}