/* =============================================================================
 * B09_Estimation_UI_Tab_RateTable.ts
 * 제비율 요율표 탭 — STmate 「원가계산기준」(wM_KAN_RATE)을 본뜸 (PLAN 12장 · 랩탑 메인).
 *
 *   - 좌측 = 도구줄 자리: `수정기준선택 ☞` [기본제비율] · `수 정` · `취 소` · `저 장`.
 *   - 본문 = 첫 탭 「☞ 공사원가계산 제잡비율」 묶음 차례 · 아래 탭 넷(첫 탭만 켜짐).
 *   - 요율 덮어쓰기 = **이 프로젝트만** · 칸마다 사유 필수 · 「기본값 ↔ 고친 값」 갈라 보임 · ↺ 되돌리기.
 *   - ⚠ 값은 서버가 냄 — 화면은 칸 주소와 새 값·사유만 돌려줌. 마스터 요율표는 안 건드림.
 * ========================================================================== */

import { ui_locales, currentLanguageIndex } from "@ui/ui_template_locale";
import { createButton, showToast } from "@ui/ui_template_elements";
import { API_BASE_URL } from "@config/config_frontend";
import type { B09Tab, B09TabContext } from "./B09_Estimation_UI_Shell_Types";

function L(key: keyof typeof ui_locales): string {
  return ui_locales[key][currentLanguageIndex];
}

interface RateAddress {
  variable: string;
  table: string | null;
  match: Record<string, string | number>;
}

interface RateCell {
  value: number | null;
  default: number | null;
  overridden: boolean;
  address: RateAddress;
}

interface RateSection {
  title: string;
  formula: string;
  columns: string[];
  rows: (string | number | RateCell)[][];
}

interface Override extends RateAddress {
  rate_percent: string;
  reason: string;
  entered_at?: string;
}

interface RateTableDto {
  status: string;
  message?: string;
  rate_version: { dataset_id: string; effective_date: string; sha256: string };
  sections: RateSection[];
  overrides: Override[];
  override_error: string;
}

/** 고치는 중인 칸 — 저장 전 캐시(지침 5장). */
interface DraftEntry {
  address: RateAddress;
  value: string;
  reason: string;
  label: string;
  default: number | null;
}

/** DFM 아래 탭 — 화면에 보이는 묶음 제목 그대로. */
const RATE_TABS = [
  "☞ 공사원가계산 제잡비율",
  "표준시장단가 제잡비율",
  "☞ 행정자치부 적용 제잡비율",
  "☞ 실적공사비 적용시 제경비율 조정계수",
];

const STYLE_ID = "b09-rate-table-styles";
function injectStyles(): void {
  if (document.getElementById(STYLE_ID)) return;
  const style = document.createElement("style");
  style.id = STYLE_ID;
  style.textContent = `
.b09rt { display: flex; flex-direction: column; gap: 8px; height: 100%; min-height: 0; }
.b09rt__meta { font-size: 12px; color: var(--color-text-secondary); }
.b09rt__warn { font-size: 12px; color: var(--color-warning-text, #8a5a00); }
.b09rt__scroll { flex: 1; overflow: auto; min-height: 0; display: flex; flex-direction: column; gap: 12px; }
.b09rt__section { border: 1px solid var(--color-border); padding: 6px 8px; }
.b09rt__title { font-weight: 600; font-size: 13px; }
.b09rt__formula { font-size: 12px; color: var(--color-text-secondary); margin-left: 6px; font-weight: normal; }
.b09rt__table { border-collapse: collapse; font-size: 12px; margin-top: 4px; }
.b09rt__table th, .b09rt__table td { border: 1px solid var(--color-border); padding: 2px 8px; }
.b09rt__table td { text-align: right; font-variant-numeric: tabular-nums; white-space: nowrap; }
.b09rt__table td.b09rt__text { text-align: left; }
.b09rt__table td.is-changed { outline: 2px solid var(--color-accent, #6c8ebf); outline-offset: -2px; }
.b09rt__default { font-size: 11px; color: var(--color-text-secondary); margin-left: 4px; }
.b09rt__table input { width: 5em; text-align: right; }
.b09rt__tabs { display: flex; gap: 2px; border-top: 1px solid var(--color-border); padding-top: 4px; }
.b09rt__tab { font-size: 12px; padding: 2px 10px; border: 1px solid var(--color-border); border-top: none; background: none; }
.b09rt__tab[aria-selected="true"] { font-weight: 600; }
.b09rt__panel { display: flex; flex-direction: column; gap: 6px; font-size: 12px; }
.b09rt__change { display: flex; flex-direction: column; gap: 2px; border-top: 1px dotted var(--color-border); padding-top: 4px; }
.b09rt__change input { width: 100%; }
.b09rt__change input.is-empty { outline: 2px solid var(--color-danger, #d9534f); }
.b09rt__buttons { display: flex; gap: 6px; flex-wrap: wrap; }
`;
  document.head.append(style);
}

function el<K extends keyof HTMLElementTagNameMap>(
  tag: K,
  className = "",
  text = "",
): HTMLElementTagNameMap[K] {
  const node = document.createElement(tag);
  if (className) node.className = className;
  if (text) node.textContent = text;
  return node;
}

function addressKey(address: RateAddress): string {
  const match = Object.keys(address.match)
    .sort()
    .map((k) => `${k}=${address.match[k]}`)
    .join("&");
  return `${address.variable}|${address.table ?? ""}|${match}`;
}

function isCell(value: unknown): value is RateCell {
  return typeof value === "object" && value !== null && "address" in value;
}

async function fetchRates(projectId: string): Promise<RateTableDto> {
  const response = await fetch(
    `${API_BASE_URL}/projects/${encodeURIComponent(projectId)}/estimation/rate-table`,
    { credentials: "include" },
  );
  const body = (await response.json()) as RateTableDto;
  if (!response.ok) throw new Error(body.message ?? `HTTP ${response.status}`);
  return body;
}

async function saveOverrides(projectId: string, overrides: Override[]): Promise<void> {
  const response = await fetch(
    `${API_BASE_URL}/projects/${encodeURIComponent(projectId)}/estimation/rate-table`,
    {
      method: "PUT",
      credentials: "include",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ overrides }),
    },
  );
  const body = (await response.json()) as { message?: string };
  if (!response.ok) throw new Error(body.message ?? `HTTP ${response.status}`);
}

/** 프로젝트별 탭 상태 — 탭을 다시 골라도 [저장] 전 고친 칸이 남음. */
const states = new Map<string, { editing: boolean; draft: Map<string, DraftEntry> }>();

function stateOf(projectId: string, data: RateTableDto) {
  let state = states.get(projectId);
  if (!state) {
    state = { editing: false, draft: new Map() };
    states.set(projectId, state);
  }
  if (!state.editing) {
    // 편집 중이 아니면 저장본으로 다시 채움 — 저장본이 곧 정본.
    state.draft = new Map(
      data.overrides.map((o) => [
        addressKey(o),
        {
          address: { variable: o.variable, table: o.table, match: o.match },
          value: o.rate_percent,
          reason: o.reason,
          label: "",
          default: null,
        },
      ]),
    );
  }
  return state;
}

function render(ctx: B09TabContext): void {
  injectStyles();
  if (!ctx.projectId) {
    ctx.body.append(el("div", "b09rt__meta", "프로젝트를 고르세요"));
    return;
  }
  const projectId = ctx.projectId;
  const load = (): void => {
    ctx.body.replaceChildren(el("div", "b09rt__meta", "요율표 받는 중…"));
    fetchRates(projectId)
      .then((data) => {
        const state = stateOf(projectId, data);
        const redraw = (): void => {
          ctx.body.replaceChildren();
          ctx.panel.replaceChildren();
          drawBody(ctx, data, state, redraw);
          drawPanel(ctx, state, redraw, load);
        };
        redraw();
      })
      .catch((error: unknown) => {
        ctx.body.replaceChildren(
          el(
            "div",
            "b09rt__meta",
            `요율표를 받지 못함 — ${error instanceof Error ? error.message : ""}`,
          ),
        );
      });
  };
  load();
}

function drawPanel(
  ctx: B09TabContext,
  state: { editing: boolean; draft: Map<string, DraftEntry> },
  redraw: () => void,
  reload: () => void,
): void {
  const box = el("div", "b09rt__panel");
  const pick = el("label", "b09rt__panel");
  pick.append(el("span", "", "수정기준선택 ☞"));
  const select = el("select");
  for (const [i, name] of ["기본제비율", "표준시장", "행자부기준"].entries()) {
    const option = el("option", "", i ? `${name} (준비 중)` : name);
    option.disabled = i > 0;
    select.append(option);
  }
  pick.append(select);
  box.append(pick);

  const buttons = el("div", "b09rt__buttons");
  if (!state.editing) {
    buttons.append(
      createButton({
        label: "수 정",
        onClick: () => {
          state.editing = true;
          redraw();
        },
      }),
    );
  } else {
    buttons.append(
      createButton({
        label: "취 소",
        variant: "ghost",
        onClick: () => {
          state.editing = false;
          reload();
        },
      }),
      createButton({
        label: "저 장",
        onClick: async () => {
          const entries = [...state.draft.values()];
          if (entries.some((entry) => !entry.reason.trim())) {
            showToast("고친 요율마다 사유를 적어야 저장됨", "error");
            redraw();
            return;
          }
          try {
            await saveOverrides(
              ctx.projectId as string,
              entries.map((entry) => ({
                ...entry.address,
                rate_percent: entry.value,
                reason: entry.reason.trim(),
              })),
            );
            state.editing = false;
            showToast("요율 덮어쓰기 저장 — 이 프로젝트만", "success");
            reload();
          } catch (error) {
            showToast(error instanceof Error ? error.message : "저장 못 함", "error");
          }
        },
      }),
    );
  }
  box.append(buttons);
  box.append(
    el(
      "span",
      "b09rt__meta",
      "고친 요율은 이 프로젝트에만 걸림 — 마스터 요율표(조달청 판)는 그대로 · 칸마다 사유 필수",
    ),
  );

  // 고친 칸 목록 — 사유 칸(편집 중에만 고침).
  const changes = [...state.draft.values()];
  box.append(el("div", "b09rt__title", `고친 요율 ${changes.length}건`));
  for (const entry of changes) {
    const row = el("div", "b09rt__change");
    row.append(
      el(
        "span",
        "",
        `${entry.label || entry.address.variable} — ${entry.default ?? "?"} → ${entry.value}`,
      ),
    );
    if (state.editing) {
      const reason = el("input");
      reason.placeholder = "사유(필수) — 예: 발주처 지침 ○○호";
      reason.value = entry.reason;
      reason.classList.toggle("is-empty", !entry.reason.trim());
      reason.addEventListener("input", () => {
        entry.reason = reason.value;
        reason.classList.toggle("is-empty", !reason.value.trim());
      });
      row.append(reason);
    } else {
      row.append(el("span", "b09rt__meta", `사유: ${entry.reason}`));
    }
    box.append(row);
  }
  box.append(
    createButton({ label: "원가계산서", variant: "ghost", onClick: () => ctx.open("cost_sheet") }),
  );
  ctx.panel.append(box);
}

function drawBody(
  ctx: B09TabContext,
  data: RateTableDto,
  state: { editing: boolean; draft: Map<string, DraftEntry> },
  redraw: () => void,
): void {
  const wrap = el("div", "b09rt");
  wrap.append(
    el(
      "div",
      "b09rt__meta",
      `원가계산기준 — 요율 판 ${data.rate_version.effective_date} (${data.rate_version.dataset_id})` +
        (state.editing ? " · 수정 중" : ""),
    ),
  );
  if (data.override_error) {
    wrap.append(
      el("div", "b09rt__warn", `⚠ 저장된 덮어쓰기가 지금 판과 안 맞음 — ${data.override_error}`),
    );
  }
  const scroll = el("div", "b09rt__scroll");
  for (const section of data.sections) {
    const box = el("div", "b09rt__section");
    const title = el("div", "b09rt__title", section.title);
    if (section.formula) title.append(el("span", "b09rt__formula", section.formula));
    box.append(title);
    const table = el("table", "b09rt__table");
    const head = el("tr");
    for (const column of section.columns) head.append(el("th", "", column));
    table.append(head);
    for (const row of section.rows) {
      const tr = el("tr");
      const rowLabel = row.filter((c) => typeof c === "string" && c).join(" ");
      row.forEach((cell, index) => {
        if (!isCell(cell)) {
          tr.append(el("td", typeof cell === "number" ? "" : "b09rt__text", String(cell)));
          return;
        }
        const key = addressKey(cell.address);
        const entry = state.draft.get(key);
        if (entry) {
          entry.label = `${section.title} · ${rowLabel} · ${section.columns[index]}`;
          entry.default = cell.default;
        }
        tr.append(rateCell(cell, entry, state, section, rowLabel, index, redraw));
      });
      table.append(tr);
    }
    box.append(table);
    scroll.append(box);
  }
  wrap.append(scroll);
  const tabs = el("div", "b09rt__tabs");
  RATE_TABS.forEach((name, i) => {
    const tab = el("button", "b09rt__tab", name);
    tab.setAttribute("aria-selected", String(i === 0));
    tab.disabled = i > 0;
    if (i > 0) tab.title = "준비 중";
    tabs.append(tab);
  });
  wrap.append(tabs);
  ctx.body.append(wrap);
}

/** 요율 칸 — 보기: 값(+기본값) · 편집: 입력 + ↺. 기본값과 같아지면 덮어쓰기에서 빠짐. */
function rateCell(
  cell: RateCell,
  entry: DraftEntry | undefined,
  state: { editing: boolean; draft: Map<string, DraftEntry> },
  section: RateSection,
  rowLabel: string,
  index: number,
  redraw: () => void,
): HTMLTableCellElement {
  const td = el("td");
  const key = addressKey(cell.address);
  const shown = entry ? entry.value : String(cell.value ?? "");
  const changed = Boolean(entry) && Number(shown) !== cell.default;
  td.classList.toggle("is-changed", changed);
  if (entry?.reason) td.title = `기본 ${cell.default} · 사유: ${entry.reason}`;
  if (!state.editing) {
    td.append(document.createTextNode(shown));
    if (changed) td.append(el("span", "b09rt__default", `(기본 ${cell.default})`));
    return td;
  }
  const input = el("input");
  input.type = "number";
  input.step = "0.001";
  input.min = "0";
  input.value = shown;
  input.addEventListener("change", () => {
    if (input.value === "" || Number(input.value) === cell.default) {
      state.draft.delete(key);
    } else {
      state.draft.set(key, {
        address: cell.address,
        value: input.value,
        reason: entry?.reason ?? "",
        label: `${section.title} · ${rowLabel} · ${section.columns[index]}`,
        default: cell.default,
      });
    }
    redraw();
  });
  td.append(input);
  if (entry) {
    const undo = el("button", "", "↺");
    undo.type = "button";
    undo.title = `기본값(${cell.default})으로 — [저 장]하면 덮어쓰기에서 빠짐`;
    undo.addEventListener("click", () => {
      state.draft.delete(key);
      redraw();
    });
    td.append(undo);
  }
  return td;
}

export const rateTableTab: B09Tab = {
  key: "rate_table",
  label: () => L("B09_Estimation_Tab_RateTable"),
  render,
};