/* =============================================================================
 * B09_Estimation_UI_Tab_PriceCompare.ts
 * B09 자재단가대비표 탭 — 원천 슬롯 여섯 · 채택 · 최소단가 (실무 `자재단가대비표` · STmate `wM_Boxa`)
 *
 *   - 칸: 호표 · 명칭 · 규격 · 단위 · 슬롯 1~6(단가 · 페이지) · 채택 · 비고.
 *   - 채택 슬롯 = 굵게·색 · 최소단가 = 「최소」 표시(서버 `min_slot`). 값 없는 슬롯은 빈칸(0 아님).
 *   - 2차(PLAN 12장 · 프로젝트 단위) — 줄마다 채택 슬롯을 고르거나 「변동없음 / 1~5 단가 / 최소단가」로 일괄.
 *     고친 줄 = 「사용자」 표시 + ↺(지우면 계산값으로). 값 없는 슬롯은 서버가 받지 않음.
 *   - ⚠ 저장은 고른 슬롯 번호만 — 금액은 서버가 다시 셈(다른 탭은 내역 한 벌을 새로 받음).
 * ========================================================================== */

import { showToast } from "@ui/ui_template_elements";
import type { B09Tab, B09TabContext } from "./B09_Estimation_UI_Shell_Types";
import { L, el, hint, numberCell, sheetTable, userMark, won } from "./B09_Estimation_UI_Sheet";
import {
  loadEdits,
  loadPriceCompare,
  saveEdits,
  type EditChange,
  type EditsDto,
  type PriceCompareDto,
} from "./B09_Estimation_UI_Store";

const SECTION = "adopted_slots";

function head(slotNames: string[]): HTMLElement {
  const thead = el("thead");
  const top = el("tr");
  const bottom = el("tr");
  const fixed = [
    L("B09_Sheet_Col_Sheet"),
    L("B09_Sheet_Col_Name"),
    L("B09_Sheet_Col_Spec"),
    L("B09_Sheet_Col_Unit"),
  ];
  for (const label of fixed) {
    const th = el("th", "", label);
    th.rowSpan = 2;
    top.append(th);
  }
  slotNames.forEach((name, index) => {
    const th = el("th", "", `${index + 1} ${name}`);
    th.colSpan = 2;
    top.append(th);
    bottom.append(
      el("th", "", L("B09_Sheet_Col_UnitPrice")),
      el("th", "", L("B09_Sheet_Col_Page")),
    );
  });
  for (const label of [L("B09_Sheet_Adopt"), L("B09_Sheet_Col_Note")]) {
    const th = el("th", "", label);
    th.rowSpan = 2;
    top.append(th);
  }
  thead.append(top, bottom);
  return thead;
}

type Row = PriceCompareDto["material_comparison"]["rows"][number];

function adoptPicker(row: Row, onPick: (slot: number) => void): HTMLSelectElement {
  const select = el("select");
  row.slots.forEach((slot, index) => {
    if (slot.price_krw === null) return; // 값 없는 원천은 고를 수 없음
    const option = el("option", "", `${index + 1} ${won(slot.price_krw)}`);
    option.value = String(index + 1);
    option.selected = index + 1 === row.adopted_slot;
    select.append(option);
  });
  select.addEventListener("change", () => onPick(Number(select.value)));
  return select;
}

/** 일괄 — 「변동없음 / 1~5 단가 / 최소단가」. 그 슬롯에 값이 있는 줄만 고침(STmate `wM_Boxa`). */
function bulkChanges(rows: Row[], choice: string): EditChange[] {
  if (choice === "none") return [];
  return rows.flatMap((row) => {
    const slot = choice === "min" ? row.min_slot : Number(choice);
    if (!slot || row.slots[slot - 1]?.price_krw === null) return [];
    return [{ section: SECTION, key: row.code, value: slot }];
  });
}

function draw(ctx: B09TabContext, projectId: string, data: PriceCompareDto, edits: EditsDto): void {
  const table = data.material_comparison;
  const userSlots = edits[SECTION] ?? {};
  const save = (changes: EditChange[]): void => {
    if (changes.length === 0) return;
    void saveEdits(projectId, changes)
      .then(() => {
        showToast(L("B09_Sheet_Saved"), "success");
        ctx.open("price_compare");
      })
      .catch((error: Error) => showToast(`${L("B09_Sheet_SaveFailed")} ${error.message}`, "error"));
  };

  const bar = el("div", "b09s-bar");
  const bulk = el("select");
  const choices: Array<[string, string]> = [
    ["none", L("B09_Sheet_Bulk_None")],
    ...[1, 2, 3, 4, 5].map((n): [string, string] => [
      String(n),
      `${n} ${table.slot_names[n - 1] ?? ""}`,
    ]),
    ["min", L("B09_Sheet_Bulk_Min")],
  ];
  for (const [value, label] of choices) {
    const option = el("option", "", label);
    option.value = value;
    bulk.append(option);
  }
  const apply = el("button", "b09s-undo", L("B09_Sheet_Apply"));
  apply.type = "button";
  apply.addEventListener("click", () => save(bulkChanges(table.rows, bulk.value)));
  bar.append(el("span", "b09s-head", L("B09_Sheet_Bulk")), bulk, apply);

  const { wrap, tbody } = sheetTable(head(table.slot_names));
  table.rows.forEach((row, index) => {
    const tr = el("tr", row.code in userSlots ? "is-user" : "");
    tr.append(
      el("td", "", String(index + 1)),
      el("td", "", row.name),
      el("td", "", row.spec),
      el("td", "", row.unit),
    );
    row.slots.forEach((slot, slotIndex) => {
      const price = numberCell(won(slot.price_krw));
      if (slot.adopted) price.classList.add("b09s-adopted");
      if (row.min_slot === slotIndex + 1) price.append(el("span", "b09s-min", L("B09_Sheet_Min")));
      tr.append(price, el("td", "", slot.source_note));
    });
    const adopt = el("td");
    adopt.append(
      adoptPicker(row, (slot) => save([{ section: SECTION, key: row.code, value: slot }])),
    );
    if (row.code in userSlots) {
      adopt.append(userMark(() => save([{ section: SECTION, key: row.code, value: null }])));
    }
    tr.append(adopt, el("td", "b09s-note", row.note));
    tbody.append(tr);
  });
  ctx.body.append(el("div", "b09s-title", L("B09_Sheet_Tab_PriceCompare")), bar, wrap);
  if (table.rows.length === 0) ctx.body.append(hint(L("B09_Sheet_EmptyGroup")));
  for (const note of table.notes) ctx.body.append(hint(note));
}

export const priceCompareTab: B09Tab = {
  key: "price_compare",
  label: () => L("B09_Sheet_Tab_PriceCompare"),
  render(ctx) {
    if (!ctx.projectId) {
      ctx.body.append(hint(L("B09_Sheet_NoProject")));
      return;
    }
    const projectId = ctx.projectId;
    ctx.body.append(hint(L("B09_Sheet_Loading")));
    Promise.all([loadPriceCompare(projectId), loadEdits(projectId)])
      .then(([data, stored]) => {
        ctx.body.replaceChildren();
        draw(ctx, projectId, data, stored.edits);
        for (const line of stored.skipped) {
          ctx.body.append(hint(`${L("B09_Sheet_EditSkipped")} ${line}`, true));
        }
      })
      .catch((error: Error) => {
        ctx.body.replaceChildren(hint(`${L("B09_Sheet_LoadFailed")} ${error.message}`, true));
      });
  },
};