/* =============================================================================
 * M02_MasterTemplete_Sangeun_Unit.ts
 * 단가산출(SK) 단위 환산 칸(PLAN 728-2 · 요구서_내역19 3장 5) — 바탕 기준단위(「100본」) → SK 단위 근거 글 ·
 *   같은 성격 = 배 자동(글만) · 성격 다름 = 환산 계수 칸 · 부피 ↔ 무게 = 단위중량 표(CC000337) 고르기.
 *   칸 보임 · 근거 글 = `swapUnit`(짝 `A00_Common/master_unit_swap.ts`) · 셈 = 서버(`M02_Sangeun_Calc.ratio_of`)
 *   문서 칸 `환산` {계수 | 단위중량 {종별, 형상}}(꼴 = 서버 `M02_Sangeun_Doc._swap_how`) · 바꿈 = 캐시 → [저장].
 * ========================================================================== */

import { el } from "@ui/ui_template_elements";
import { createInputField, createSelectField } from "@ui/ui_template_input";
import { t as L } from "@ui/ui_template_locale";
import { createText } from "@ui/ui_template_text";
import { swapUnit } from "../A00_Common/master_unit_swap";
import { loadTable } from "../M01_MasterData/M01_MasterData_UI_Logic_Note";

export interface SwapHow {
  계수?: number;
  단위중량?: { 종별: string; 형상: string };
}

const WEIGHT_TABLE = "CC000337";

/** 결과단위 「원/100본」 → 기준단위 「100본」(SK 단위 처음 값) */
export const baseUnitOf = (result: string): string => result.replace(/^원\s*\/\s*/, "").trim();

/** 단위중량 표 줄 → ㎏/㎥(위 끝 · 서버 `master_unit.unit_weight` 기본과 같음) */
const rhoOf = (row: Record<string, unknown> | undefined): number | null =>
  row && Number.isFinite(Number(row.위)) ? Number(row.위) : null;

/** 환산 칸 — 「식」 · 빈 단위 · 바탕 없음 = null(옛 셈) */
export function buildUnitSwap(opt: {
  result: string;
  unit: string;
  how: SwapHow | undefined;
  edit: boolean;
  onChange: (how: SwapHow | undefined) => void;
}): HTMLElement | null {
  const have = baseUnitOf(opt.result);
  if (!have || !opt.unit || opt.unit === "식") return null;
  const how = opt.how ?? {};
  const probe = swapUnit(have, opt.unit, 1000, how.계수);
  const root = el("div", { className: "m02-sk__tags", attrs: { "data-sk-swap": "" } });
  const note = createText("", "muted", 14);
  const say = (rho: number | null): void => {
    const got = swapUnit(have, opt.unit, rho, how.계수);
    note.textContent = got.근거;
    note.dataset.skSwapBlocked = got.배 === null ? "1" : "";
  };
  if (probe.계수 === "사용자") {
    const [, ua] = probe.가;
    const [, ub] = probe.나;
    const box = createInputField({
      label: `${L("M02_SangeunSwapCoef")} — 1 ${ua} = ? ${ub}`,
      type: "number",
      value: how.계수 != null ? String(how.계수) : "",
      min: 0,
      compact: true,
      size: 28,
    });
    box.input.dataset.skSwapCoef = "";
    box.input.disabled = !opt.edit;
    box.input.addEventListener("change", () => {
      const v = Number(box.input.value);
      opt.onChange(Number.isFinite(v) && v > 0 ? { 계수: v } : undefined);
    });
    root.append(box.root);
  } else if (probe.계수 === "단위중량") {
    const pick = how.단위중량;
    const value = pick ? `${pick.종별}|${pick.형상}` : "";
    const select = createSelectField({
      label: `${L("M02_SangeunSwapWeight")} (${WEIGHT_TABLE})`,
      options: [{ value: "", text: L("M02_SangeunSwapPick") }],
      value,
      compact: true,
      size: 28,
      disabled: !opt.edit,
      onChange: (v) => {
        const [종별, 형상] = v.split("|");
        opt.onChange(v ? { 단위중량: { 종별, 형상 } } : undefined);
      },
    });
    select.select.dataset.skSwapWeight = "";
    root.append(select.root);
    void loadTable(WEIGHT_TABLE).then((table) => {
      const rows = table?.줄 ?? [];
      select.setOptions(
        [
          { value: "", text: L("M02_SangeunSwapPick") },
          ...rows.map((r) => ({
            value: `${String(r.종별)}|${String(r.형상)}`,
            text: `${String(r.종별)} · ${String(r.형상)} (${String(r.위)}㎏/㎥)`,
          })),
        ],
        value,
      );
      say(rhoOf(rows.find((r) => r.종별 === pick?.종별 && r.형상 === pick?.형상)));
    });
  }
  say(null);
  if (!root.childElementCount && !note.textContent) return null;
  root.append(note);
  return root;
}