/* =============================================================================
 * B02_ProjRegister_UI_Page.ts
 * 로그인 후 02: 프로젝트 등록 (신규 임도 설계 프로젝트 기본 정보 입력)
 *
 * 제약 준수 (frontend.md):
 *   - 모든 문구는 ui_template_locale.ts 참조 (하드코딩 금지, §3).
 *   - 색상/간격은 theme.css 변수 + 공통 컴포넌트만 사용 (§1, §2).
 *   - 이벤트 핸들러는 onB02_[기능]_[액션] 명명 (§4).
 *   - 백엔드 전송 전 1차 유효성 검사 (§4).
 * ========================================================================== */

import { ui_locales, currentLanguageIndex } from "@ui/ui_template_locale";
import {
  createButton,
  createInputField,
  createSelectField,
  createCard,
  hideLoadingOverlay,
  showLoadingOverlay,
  showToast,
} from "@ui/ui_template_elements";
import { isBlank } from "@util/common_util_validate";
import {
  fetchCompanyAssets,
  fetchCompanyMembers,
  fetchDashboardMe,
  fetchUserCompany,
} from "../B01_Dashboard/B01_Dashboard_Api_Fetch";
import { createAssetField } from "../B01_Dashboard/B01_Dashboard_UI_AssetPicker";
import { openAddMemberModal } from "../B01_Dashboard/B01_Dashboard_UI_Modals";
import { navigateTo } from "../A00_Common/router";
import { API_BASE_URL, CURRENT_PROJECT_ID_KEY, ROUTES } from "@config/config_frontend";
import "./B02_ProjRegister_UI_Style.css";

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

/* -----------------------------------------------------------------------------
 * 페이지 진입점
 * -------------------------------------------------------------------------- */
export function renderB02ProjRegister(root: HTMLElement): void {
  const page = document.createElement("div");
  page.className = "b02-proj";

  const header = document.createElement("div");
  header.className = "b02-proj__header";
  const title = document.createElement("h1");
  title.className = "b02-proj__title";
  title.textContent = L("B02_Proj_Title");
  const subtitle = document.createElement("p");
  subtitle.className = "b02-proj__subtitle";
  subtitle.textContent = L("B02_Proj_Subtitle");
  header.append(title, subtitle);

  // 입력 필드
  const nameField = createInputField({
    label: L("B02_Proj_Field_Name"),
    placeholder: L("B02_Proj_Field_Name_Placeholder"),
    required: true,
  });
  const regionField = createInputField({
    label: L("B02_Proj_Field_Region"),
    placeholder: L("B02_Proj_Field_Region_Placeholder"),
    required: true,
  });
  // 임도 종류 3종 — 현행 규칙 기준(지선임도 폐지, 계류보전은 사방사업 구분이라 제외).
  // 이 값이 B05 계획선의 법정 기준(설계속도 선택지·종단기울기 상한)을 정한다
  // (2026-08-19 사용자 확정).
  const roadTypeField = createSelectField({
    label: L("B02_Proj_Field_RoadType"),
    options: [
      { value: "main", text: L("B02_Proj_RoadType_Main") },
      { value: "fire", text: L("B02_Proj_RoadType_Fire") },
      { value: "work", text: L("B02_Proj_RoadType_Work") },
    ],
  });
  const currentYear = new Date().getFullYear();
  const yearField = createInputField({
    label: L("B02_Proj_Field_Year"),
    type: "number",
    value: String(currentYear),
    min: 2000,
    max: currentYear + 5,
  });
  const lengthField = createInputField({
    label: L("B02_Proj_Field_Length"),
    placeholder: L("B02_Proj_Field_Length_Placeholder"),
    type: "number",
    min: 0,
  });
  // 계획노선 자료가 공사지 전체일 수 있어 쓸 구간을 받는다 (2026-09-04 사용자 지시).
  // 둘 다 비우면 전 구간을 쓴다.
  const routeStartField = createInputField({
    label: "노선 시작 누가거리 (m)",
    placeholder: "비우면 처음부터",
    type: "number",
    min: 0,
  });
  const routeEndField = createInputField({
    label: "노선 종료 누가거리 (m)",
    placeholder: "비우면 끝까지",
    type: "number",
    min: 0,
  });
  const memoField = createInputField({
    label: L("B02_Proj_Field_Memo"),
    placeholder: L("B02_Proj_Field_Memo_Placeholder"),
    type: "text",
  });

  // 도면 표제란·표지 값 — 프로젝트 수정 모달과 같은 항목을 등록 때부터 받는다
  // (2026-09-02 사용자 지시). 비워 두면 도면에 빈칸으로 나간다.
  const clientOrgField = createInputField({ label: "시행청 (도면 표제란)" });
  const projectNumberField = createInputField({
    label: "연도·기번 (표지)",
    placeholder: "예: 2026년 간선임도(기번3-울진.대흥)",
  });
  const workAmountField = createInputField({ label: "사업량 (표지)", placeholder: "예: L=2.14km" });
  const designDateField = createInputField({ label: "설계일자 (도면 표제란)", type: "date" });

  const NEW_MEMBER = "__new__";
  const person = (label: string) =>
    createSelectField({ label, options: [{ value: "", text: "(미지정)" }] });
  const pmField = person("과업책임자 (도면 표제란)");
  const fieldLeadField = person("분야별책임자 (도면 표제란)");
  const designerField = person("설계자 (도면 표제란)");
  const personSelects = [pmField.select, fieldLeadField.select, designerField.select];
  // 로고 칸은 회사 자산을 받아야 세울 수 있어 자리만 먼저 잡는다.
  const logoSlot = document.createElement("div");
  let logoValue: () => number | null = () => null;

  void (async () => {
    const [me, company] = await Promise.all([
      fetchDashboardMe(),
      fetchUserCompany().catch(() => null),
    ]);
    const [members, assets] = await Promise.all([
      fetchCompanyMembers().catch(() => []),
      fetchCompanyAssets().catch(() => []),
    ]);
    const memberText = (member: (typeof members)[number]) =>
      member.position ? `${member.name} (${member.position})` : member.name;
    const addOption = (select: HTMLSelectElement, value: string, text: string) => {
      const option = document.createElement("option");
      option.value = value;
      option.textContent = text;
      select.append(option);
    };
    for (const select of personSelects) {
      for (const member of members) addOption(select, String(member.id), memberText(member));
      // 계정을 만드는 것은 회사 관리자 권한이라 일반 사용자에게는 보이지 않는다.
      if (me.role !== "USER") addOption(select, NEW_MEMBER, "+ 신규 등록…");
    }
    for (const select of personSelects) {
      let last = select.value;
      select.addEventListener("change", () => {
        if (select.value !== NEW_MEMBER) {
          last = select.value;
          return;
        }
        select.value = last;
        openAddMemberModal((member) => {
          for (const other of personSelects) {
            const option = document.createElement("option");
            option.value = String(member.id);
            option.textContent = memberText(member);
            other.insertBefore(option, other.options[other.options.length - 1]);
          }
          select.value = String(member.id);
          last = select.value;
        });
      });
    }
    if (company) {
      // 회사 대표 로고가 기본값 — 프로젝트마다 다른 로고를 쓰면 여기서 바꾼다.
      const logo = createAssetField(
        "회사 로고 (도면 표제란)",
        "LOGO",
        assets,
        company.logo_asset_id ?? null,
        company.id,
        me,
      );
      logoValue = logo.value;
      logoSlot.append(logo.root);
    }
  })();

  const submitBtn = createButton({
    label: L("B02_Proj_Submit"),
    variant: "filled",
    onClick: onB02_Proj_Submit_Click,
  });
  submitBtn.classList.add("b02-proj__submit");

  const idOrNull = (select: HTMLSelectElement): number | null =>
    select.value && select.value !== NEW_MEMBER ? Number(select.value) : null;

  async function onB02_Proj_Submit_Click(): Promise<void> {
    nameField.setError();
    regionField.setError();
    yearField.setError();
    lengthField.setError();
    routeStartField.setError();
    routeEndField.setError();

    // 1차 유효성: 필수값 검사
    let hasError = false;
    const projectYear = Number.parseInt(yearField.input.value, 10);
    const estimatedLength = isBlank(lengthField.input.value)
      ? null
      : Number.parseFloat(lengthField.input.value);
    if (isBlank(nameField.input.value)) {
      nameField.setError(L("B02_Proj_Error_Required"));
      hasError = true;
    }
    if (isBlank(regionField.input.value)) {
      regionField.setError(L("B02_Proj_Error_Required"));
      hasError = true;
    }
    if (!Number.isInteger(projectYear) || projectYear < 2000 || projectYear > 2100) {
      yearField.setError(L("Common_Validation_NumberRange"));
      hasError = true;
    }
    if (estimatedLength !== null && (!Number.isFinite(estimatedLength) || estimatedLength < 0)) {
      lengthField.setError(L("Common_Validation_NumberRange"));
      hasError = true;
    }
    const routeStart = isBlank(routeStartField.input.value)
      ? null
      : Number.parseFloat(routeStartField.input.value);
    const routeEnd = isBlank(routeEndField.input.value)
      ? null
      : Number.parseFloat(routeEndField.input.value);
    if (routeStart !== null && (!Number.isFinite(routeStart) || routeStart < 0)) {
      routeStartField.setError(L("Common_Validation_NumberRange"));
      hasError = true;
    }
    if (routeEnd !== null && (!Number.isFinite(routeEnd) || routeEnd < 0)) {
      routeEndField.setError(L("Common_Validation_NumberRange"));
      hasError = true;
    }
    // 시작이 종료보다 뒤면 남는 구간이 없다 — 서버도 같은 규칙으로 막는다.
    if (routeStart !== null && routeEnd !== null && routeStart >= routeEnd) {
      routeEndField.setError("종료 누가거리는 시작보다 커야 합니다.");
      hasError = true;
    }
    if (hasError) return;

    showLoadingOverlay();
    try {
      const response = await fetch(`${API_BASE_URL}/b02/project`, {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        credentials: "include",
        body: JSON.stringify({
          name: nameField.input.value.trim(),
          region: regionField.input.value.trim(),
          road_type: roadTypeField.select.value,
          project_year: projectYear,
          estimated_length_m: estimatedLength,
          route_start_m: routeStart,
          route_end_m: routeEnd,
          memo: memoField.input.value.trim() || null,
          client_org: clientOrgField.input.value.trim() || null,
          project_number: projectNumberField.input.value.trim() || null,
          work_amount: workAmountField.input.value.trim() || null,
          design_date: designDateField.input.value || null,
          pm_user_id: idOrNull(pmField.select),
          field_lead_user_id: idOrNull(fieldLeadField.select),
          designer_user_id: idOrNull(designerField.select),
          logo_asset_id: logoValue(),
        }),
      });

      if (!response.ok) {
        let detail = L("Common_Status_Error");
        try {
          const errorBody = (await response.json()) as { detail?: string; message?: string };
          detail = errorBody.detail ?? errorBody.message ?? detail;
        } catch {
          detail = `${detail} (${response.status})`;
        }
        throw new Error(detail);
      }

      const data = (await response.json()) as { project_id: string };
      localStorage.setItem(CURRENT_PROJECT_ID_KEY, data.project_id);
      showToast(L("B02_Proj_Success"), "success");
      navigateTo(ROUTES.B03_FILE_INPUT);
    } catch (error) {
      const message = error instanceof Error ? error.message : L("Common_Status_Error");
      showToast(message, "error");
    } finally {
      hideLoadingOverlay();
    }
  }

  const grid = document.createElement("div");
  grid.className = "b02-proj__grid";
  grid.append(
    nameField.root,
    regionField.root,
    roadTypeField.root,
    yearField.root,
    lengthField.root,
    routeStartField.root,
    routeEndField.root,
    memoField.root,
    clientOrgField.root,
    projectNumberField.root,
    workAmountField.root,
    designDateField.root,
    pmField.root,
    fieldLeadField.root,
    designerField.root,
    logoSlot,
  );

  const card = createCard({ body: [grid, submitBtn], raised: true });
  page.append(header, card);
  root.append(page);
}