/* =============================================================================
 * M01_MasterData_UI_Combo_Preview.ts
 * 조합 미리 보기 — 담은 로직 저마다 받은 입력값을 서버 미리 보기(`POST /combo/preview`)에 실어 비목별 합계를 받음
 * 입력값(수량)은 이 화면 안에만 두고 조합에 저장하지 않음(계약 9장)
 * ========================================================================== */

import { createInputField, createSelectField, el } from "@ui/ui_template_elements";
import { fetchLogic, type LogicInput } from "./M01_MasterData_UI_Logic_Api";
import { previewCombo, type Combo } from "./M01_MasterData_UI_Combo_Api";
import { tc, type ComboTextKey } from "./M01_MasterData_UI_Combo_Text";

const COSTS = ["노무비", "재료비", "경비"] as const;
const LABEL: Record<(typeof COSTS)[number], ComboTextKey> = {
  노무비: "Prev_Labor",
  재료비: "Prev_Material",
  경비: "Prev_Expense",
};

const num = (v: string): number | string => (v.trim() !== "" && !isNaN(Number(v)) ? Number(v) : v);
const fmt = (n: number): string => n.toLocaleString("ko-KR", { maximumFractionDigits: 4 });

/** 로직 입력 정의 → 처음 값(고르기 첫째 · 범위 아래끝) */
const initial = (i: LogicInput): string => String(i.고르기?.[0] ?? i.범위?.[0] ?? "");

/** 입력 칸 — 바꾼 값은 `values`(이 화면 메모)에만 적음 */
function inputCell(
  input: LogicInput,
  key: string,
  values: Record<string, Record<string, string>>,
): HTMLElement {
  const mine = (values[key] ??= {});
  const value = mine[input.이름] ?? initial(input);
  mine[input.이름] = value;
  const choices = input.고르기?.map((v) => ({ value: String(v), text: String(v) }));
  const field = choices
    ? createSelectField({ options: choices, value, compact: true, label: input.이름 })
    : createInputField({ type: "text", label: input.이름 });
  const control = "select" in field ? field.select : field.input;
  control.value = value;
  control.setAttribute("data-input", `${key}|${input.이름}`);
  control.addEventListener("input", () => (mine[input.이름] = control.value));
  control.addEventListener("change", () => (mine[input.이름] = control.value));
  return field.root;
}

export interface PreviewHandle {
  root: HTMLElement;
  /** 담은 로직이 바뀐 뒤 입력 칸을 다시 그림 */
  redraw: () => Promise<void>;
}

export function buildPreview(combo: () => Combo): PreviewHandle {
  const values: Record<string, Record<string, string>> = {};
  /** 서버가 받을 꼴 — 원래 숫자·고르기 값으로 되돌림 */
  const inputs = new Map<string, LogicInput[]>();
  const form = el("div", { className: "m01-logic__stack" });
  const out = el("div", { attrs: { "data-combo": "preview" } });
  const rowOf = (cells: string[], note = "", bold = false): HTMLElement =>
    el("tr", {
      className: bold ? "m01lab__subtotal" : "",
      children: cells.map((t, i) => el("td", { text: i === 0 && note ? `${t} — ${note}` : t })),
    });

  const run = async (): Promise<void> => {
    out.replaceChildren(el("p", { className: "m01-logic__muted", text: "…" }));
    const send: Record<string, Record<string, unknown>> = {};
    for (const [key, defs] of inputs) {
      send[key] = {};
      for (const i of defs) {
        const raw = values[key]?.[i.이름] ?? initial(i);
        if (raw.trim() === "") continue; // 빈 칸은 안 보냄(로직 화면과 같음)
        send[key][i.이름] = i.고르기?.find((o) => String(o) === raw) ?? num(raw);
      }
    }
    let got;
    try {
      got = await previewCombo(combo(), send);
    } catch (error) {
      out.replaceChildren(
        el("p", { text: `${tc("Prev_Fail")}: ${error instanceof Error ? error.message : ""}` }),
      );
      return;
    }
    const trs = got.줄.map((l) =>
      rowOf(
        [
          `${l.로직} ${l.이름}`,
          fmt(l.노무비 ?? 0),
          fmt(l.재료비 ?? 0),
          fmt(l.경비 ?? 0),
          fmt(l.계 ?? 0),
        ],
        l.ok ? "" : `${tc("Prev_Fail")}: ${l.까닭 ?? ""}`,
      ),
    );
    trs.push(
      rowOf(
        [tc("Prev_Sum"), fmt(got.노무비), fmt(got.재료비), fmt(got.경비), fmt(got.계)],
        "",
        true,
      ),
    );
    const heads = [tc("Prev_Row"), ...COSTS.map((c) => tc(LABEL[c])), tc("Prev_Sum")];
    out.replaceChildren(
      el("table", {
        className: "m01-master__grid",
        children: [
          el("thead", {
            children: [el("tr", { children: heads.map((t) => el("th", { text: t })) })],
          }),
          el("tbody", { children: trs }),
        ],
      }),
    );
  };

  const button = el("button", {
    className: "ui-btn ui-btn--filled",
    text: tc("Prev_Run"),
    attrs: { type: "button", "data-combo": "run" },
  });
  button.addEventListener("click", () => void run());

  const redraw = async (): Promise<void> => {
    const blocks: HTMLElement[] = [];
    inputs.clear();
    for (const row of combo().담은로직) {
      try {
        const one = await fetchLogic(row.로직);
        inputs.set(row.로직, one.logic.입력);
        blocks.push(
          el("div", {
            className: "m01lab__info",
            children: [
              el("strong", {
                className: "m01lab__cell--wide",
                text: `${row.로직} ${one.logic.이름}`,
              }),
              ...one.logic.입력.map((i) => inputCell(i, row.로직, values)),
            ],
          }),
        );
      } catch {
        /* 못 읽은 로직은 미리 보기에서 그 줄만 까닭이 뜸 */
      }
    }
    form.replaceChildren(...blocks);
    out.replaceChildren(el("p", { className: "m01-logic__muted", text: tc("Prev_Wait") }));
  };

  const root = el("section", {
    className: "m01lab__box m01-logic__section",
    children: [
      el("div", {
        className: "m01-logic__section-head",
        children: [el("h3", { text: tc("Prev_Title") })],
      }),
      el("h4", { text: tc("Prev_Inputs") }),
      form,
      button,
      out,
    ],
  });
  return { root, redraw };
}