/* =============================================================================
 * B08_DesignDetail_UI_Page.ts
 * 로그인 후 07: 4차 워크플로우 (상세 설계) — 독립형 2D CAD 임베드
 *
 * B08_DesignDetail/openwebcad를 프로젝트 소유 B08 CAD 앱으로 빌드하여
 * /b08-cad 경로로 서빙한다. 업무 도면은 추후 same-origin postMessage로
 * JSON만 전달하며 DXF/DWG 파싱은 이 브라우저 앱에서 수행하지 않는다.
 *
 * 레이아웃 (사용자 지시): 사이드 패널 빈 상태 유지 + 상세 영역 CAD 화면.
 * 제약 준수 (frontend.md §2 3단 레이아웃): createWorkflowLayout 재사용.
 * ========================================================================== */

import "./B08_DesignDetail_UI_Style.css";
import { attachCollapsible } from "@ui/ui_template_collapsible";
import { ui_locales, currentLanguageIndex } from "@ui/ui_template_locale";
import {
  createButton,
  hideLoadingOverlay,
  showLoadingOverlay,
  showToast,
} from "@ui/ui_template_elements";
import { createWorkflowLayout } from "@ui/ui_template_workflow_layout";
import { CURRENT_PROJECT_ID_KEY } from "@config/config_frontend";
import { workflowSteps } from "../A00_Common/b_page_scaffold";
import {
  fetchWorkflowState,
  goToWorkflowStage,
  WORKFLOW_STEP_ROUTES,
  type WorkflowState,
} from "../A00_Common/b_workflow_nav";
import {
  confirmDesignDrawing,
  fetchDesignDrawing,
  fetchDesignDrawingList,
  invalidateDesignDrawing,
  type CadDrawing,
  type CrossDesignInfo,
  type DesignDrawingItem,
  type DesignDrawingResponse,
  type QuantityTable,
} from "./B08_DesignDetail_Api_Fetch";

/** CAD 앱 수량 패널로 넘기는 설계 컨텍스트 (openwebcad DesignMeta와 동일 형식). */
interface DesignMeta {
  kind: "cross" | "longitudinal";
  title: string;
  info: string;
  confirmed: boolean;
  quantityTable: QuantityTable | null;
  hasPrev: boolean;
  hasNext: boolean;
}

/** CAD 저장 응답 (도면 + 편집된 수량표). */
interface SaveResult {
  drawing: CadDrawing;
  quantityTable: QuantityTable | null;
}

/** B08 독립형 CAD 정적 경로 (main.py 마운트, dev는 vite proxy 위임) */
const B08_CAD_APP_URL = "/b08-cad/index.html";

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

const CAD_LOAD_MESSAGE = "aislo:b08:load-drawing";
const CAD_READY_MESSAGE = "aislo:b08:drawing-ready";
const CAD_LOADED_MESSAGE = "aislo:b08:drawing-loaded";
const CAD_ERROR_MESSAGE = "aislo:b08:drawing-error";
const CAD_CHANGED_MESSAGE = "aislo:b08:drawing-changed";
const CAD_SAVE_REQUEST_MESSAGE = "aislo:b08:save-request";
const CAD_SAVE_RESPONSE_MESSAGE = "aislo:b08:save-response";
const CAD_NAVIGATE_MESSAGE = "aislo:b08:navigate";

/** 측점 간격을 연속 chainage 차이의 최빈값으로 추정한다 (B06 그래프와 동일 방식). */
function inferStationInterval(chainages: number[]): number {
  const counts = new Map<number, number>();
  const sorted = [...chainages].sort((a, b) => a - b);
  for (let index = 1; index < sorted.length; index += 1) {
    const difference = sorted[index] - sorted[index - 1];
    if (difference <= 0) continue;
    const rounded = Math.round(difference * 10) / 10;
    counts.set(rounded, (counts.get(rounded) ?? 0) + 1);
  }
  return (
    [...counts.entries()].sort(
      ([intervalA, countA], [intervalB, countB]) => countB - countA || intervalB - intervalA,
    )[0]?.[0] ?? 1
  );
}

/** 측점 번호+나머지 표기 (B06 그래프 영역 횡단도 라벨과 동일 형식, 예: "2+0.0"). */
function stationLabel(chainage: number, interval: number): string {
  const safeInterval = interval > 0 ? interval : 1;
  let stationNumber = Math.floor((chainage + 1e-6) / safeInterval);
  let remainder = chainage - stationNumber * safeInterval;
  if (Math.abs(remainder) < 0.05) remainder = 0;
  if (remainder >= safeInterval - 0.05) {
    stationNumber += 1;
    remainder = 0;
  }
  return `${stationNumber}+${remainder.toFixed(1)}`;
}

/** B06 확정 산출물 기반 도면 목록 패널. */
function buildDrawingSidePanel(
  drawings: DesignDrawingItem[],
  stationInterval: number,
  onSelect: (drawing: DesignDrawingItem) => void,
  errorMessage?: string,
): HTMLDivElement {
  const panel = document.createElement("div");
  panel.className = "b08-drawing-list";
  const heading = document.createElement("div");
  heading.className = "b08-drawing-list__heading";
  const title = document.createElement("strong");
  title.textContent = "설계 도면";
  const count = document.createElement("span");
  count.textContent = `${drawings.length}건`;
  heading.append(title, count);
  panel.append(heading);

  if (errorMessage || drawings.length === 0) {
    const empty = document.createElement("p");
    empty.className = "b08-drawing-list__empty";
    empty.textContent = errorMessage ?? "확정된 종·횡단 도면이 없습니다.";
    panel.append(empty);
    return panel;
  }

  const groups: [string, DesignDrawingItem["kind"], DesignDrawingItem[]][] = [
    ["종단도", "longitudinal", drawings.filter((item) => item.kind === "longitudinal")],
    ["횡단도", "cross", drawings.filter((item) => item.kind === "cross")],
  ];
  for (const [label, kind, items] of groups) {
    if (!items.length) continue;
    const section = document.createElement("section");
    // ui-sidebar-section: 사이드 컨테이너 공통 외곽선(B04~B06과 통일, 2026-08-06 사용자 지시).
    section.className = "b08-drawing-group ui-collapsible ui-sidebar-section";
    section.dataset.kind = kind;
    const sectionTitle = document.createElement("h3");
    sectionTitle.className = "ui-collapsible__title";
    sectionTitle.textContent = `${label} ${items.length}`;
    section.append(sectionTitle);
    for (const drawing of items) {
      const button = document.createElement("button");
      button.type = "button";
      button.className = "b08-drawing-button";
      button.dataset.drawingId = drawing.id;
      button.dataset.confirmed = String(drawing.confirmed);
      const name = document.createElement("span");
      name.className = "b08-drawing-button__name";
      name.textContent =
        drawing.kind === "cross" && typeof drawing.chainage_m === "number"
          ? stationLabel(drawing.chainage_m, stationInterval)
          : drawing.label;
      button.append(name);
      button.addEventListener("click", () => onSelect(drawing));
      section.append(button);
    }
    panel.append(section);
  }
  attachCollapsible(panel);
  return panel;
}

const GROUND_TYPE_LABEL: Record<CrossDesignInfo["ground_type"], keyof typeof ui_locales> = {
  soil: "B06_Design_Ground_Soil",
  ripping_rock: "B06_Design_Ground_Ripping",
  blasting_rock: "B06_Design_Ground_Blasting",
};

/** 단면유형에서 절토측 표기를 유도한다. */
function cutSideLabel(mode: CrossDesignInfo["section_mode"]): string {
  if (mode === "left_cut") return L("B06_Design_Ditch_Left");
  if (mode === "right_cut") return L("B06_Design_Ditch_Right");
  if (mode === "both_cut") return L("B06_Design_Mode_BothCut");
  return L("B06_Design_Mode_BothFill");
}

/** 측구 규격 표시 문자열 (design 신구조: 형식별 ditch spec, F-2 호환). */
function ditchLabel(design: CrossDesignInfo): string {
  const ditch = design.ditch;
  if (!ditch || ditch.type === "none" || design.ditch_enabled === false) return "없음";
  if (ditch.type === "l_type")
    return `L형 ${ditch.width_m.toFixed(2)}×${ditch.depth_m.toFixed(2)}m`;
  return `${ditch.top_width_m.toFixed(2)}×${ditch.depth_m.toFixed(2)}m`;
}

function infoRow(label: string, value: string): HTMLElement {
  const row = document.createElement("div");
  row.className = "b08-info__row";
  const key = document.createElement("span");
  key.className = "b08-info__key";
  key.textContent = label;
  const val = document.createElement("span");
  val.className = "b08-info__val";
  val.textContent = value;
  row.append(key, val);
  return row;
}

/** 선택 횡단도의 지반정보/계획정보를 2분할로 렌더한다 (잠정치, B08 확정 시 재계산). */
function buildDesignInfoPanel(title: string, design: CrossDesignInfo | null): HTMLElement {
  const panel = document.createElement("div");
  panel.className = "b08-info";
  const heading = document.createElement("div");
  heading.className = "b08-info__heading";
  const stationName = document.createElement("strong");
  stationName.textContent = `${L("B08_Info_Station")} ${title}`;
  const confirmed = design?.status === "confirmed";
  const badge = document.createElement("span");
  badge.className = `b08-info__badge${confirmed ? " b08-info__badge--confirmed" : ""}`;
  badge.textContent = confirmed ? L("B08_Info_Confirmed") : L("B08_Info_Provisional");
  heading.append(stationName, badge);
  panel.append(heading);

  if (!design) {
    const empty = document.createElement("p");
    empty.className = "b08-info__empty";
    empty.textContent = L("B08_Info_NoDesign");
    panel.append(empty);
    return panel;
  }

  const ground = document.createElement("section");
  ground.className = "b08-info__block";
  const groundTitle = document.createElement("h4");
  groundTitle.textContent = L("B08_Info_Ground_Title");
  ground.append(
    groundTitle,
    infoRow(L("B08_Info_GroundType"), L(GROUND_TYPE_LABEL[design.ground_type])),
    infoRow(L("B08_Info_CutSide"), cutSideLabel(design.section_mode)),
    infoRow(
      L("B08_Info_DitchSide"),
      design.ditch_side === "left" ? L("B06_Design_Ditch_Left") : L("B06_Design_Ditch_Right"),
    ),
  );

  const plan = document.createElement("section");
  plan.className = "b08-info__block";
  const planTitle = document.createElement("h4");
  planTitle.textContent = L("B08_Info_Plan_Title");
  plan.append(
    planTitle,
    infoRow(L("B08_Info_DesignElevation"), `${design.design_elevation_m.toFixed(2)}m`),
    infoRow(L("B08_Info_CutSlope"), `1:${design.cut_slope_ratio}`),
    infoRow(L("B08_Info_FillSlope"), `1:${design.fill_slope_ratio}`),
    infoRow(L("B08_Info_RoadWidth"), `${design.roadbed_width_m.toFixed(2)}m`),
    infoRow(L("B08_Info_Ditch"), ditchLabel(design)),
    infoRow(L("B08_Info_CutArea"), `${design.cut_area_m2.toFixed(2)}㎡`),
    infoRow(L("B08_Info_FillArea"), `${design.fill_area_m2.toFixed(2)}㎡`),
  );

  panel.append(ground, plan);
  return panel;
}

/* -----------------------------------------------------------------------------
 * 페이지 진입점
 * -------------------------------------------------------------------------- */
export async function renderB08DesignDetail(root: HTMLElement): Promise<void> {
  const projectId = localStorage.getItem(CURRENT_PROJECT_ID_KEY);
  let workflowState: WorkflowState | undefined;
  let drawings: DesignDrawingItem[] = [];
  let drawingError: string | undefined;
  if (projectId) {
    const [workflowResult, drawingResult] = await Promise.allSettled([
      fetchWorkflowState(projectId),
      fetchDesignDrawingList(projectId),
    ]);
    if (workflowResult.status === "fulfilled") workflowState = workflowResult.value;
    if (drawingResult.status === "fulfilled") drawings = drawingResult.value.drawings;
    else
      drawingError =
        drawingResult.reason instanceof Error
          ? drawingResult.reason.message
          : "도면 목록을 불러오지 못했습니다.";
  }

  const cadHost = document.createElement("div");
  cadHost.className = "b08-cad-host";
  const frame = document.createElement("iframe");
  frame.className = "b08-cad-frame";
  frame.src = B08_CAD_APP_URL;
  frame.title = L("B08_Design_Title");
  const license = document.createElement("a");
  license.className = "b08-cad-license";
  license.href = "/b08-cad/THIRD_PARTY_LICENSES.txt";
  license.target = "_blank";
  license.rel = "noreferrer";
  license.textContent = "Drawing engine based on OpenWebCAD · MIT License";
  cadHost.append(frame, license);

  const crossChainages = drawings
    .filter((item) => item.kind === "cross" && typeof item.chainage_m === "number")
    .map((item) => item.chainage_m as number);
  const stationInterval = inferStationInterval(crossChainages);

  let cadReady = false;
  let pendingLoad: { drawing: CadDrawing; meta: DesignMeta } | undefined;
  let currentDrawing: DesignDrawingItem | undefined;
  let currentIndex = -1;
  let currentConfirmed = false;
  // 단계 완료 기준은 횡단도만 본다 (종단도 확정 여부는 다음 단계 진행과 무관).
  const isCross = (item: DesignDrawingItem): boolean => item.kind === "cross";
  let allDrawingsConfirmed =
    drawings.some(isCross) && drawings.filter(isCross).every((item) => item.confirmed);
  let resolveSave: ((payload: SaveResult) => void) | undefined;
  let drawingListEl: HTMLElement | undefined;
  const infoPanelHost = document.createElement("div");
  infoPanelHost.className = "b08-info-host";

  const updateInfoPanel = (drawing: DesignDrawingItem, response: DesignDrawingResponse): void => {
    if (drawing.kind !== "cross") {
      infoPanelHost.replaceChildren();
      return;
    }
    const title =
      typeof drawing.chainage_m === "number"
        ? stationLabel(drawing.chainage_m, stationInterval)
        : drawing.label;
    infoPanelHost.replaceChildren(buildDesignInfoPanel(title, response.design ?? null));
  };

  const confirmButton = createButton({
    label: "현재 도면 확정",
    variant: "filled",
    onClick: () => void confirmCurrentDrawing(),
  });
  confirmButton.disabled = true;

  const findButton = (drawingId: string) =>
    drawingListEl?.querySelector<HTMLButtonElement>(
      `.b08-drawing-button[data-drawing-id="${drawingId}"]`,
    ) ?? undefined;

  const highlightActive = (drawingId: string) => {
    drawingListEl?.querySelectorAll<HTMLButtonElement>(".b08-drawing-button").forEach((item) => {
      item.dataset.active = String(item.dataset.drawingId === drawingId);
    });
  };

  const buildMeta = (
    drawing: DesignDrawingItem,
    response: DesignDrawingResponse,
    index: number,
  ): DesignMeta => ({
    kind: drawing.kind,
    title:
      drawing.kind === "cross" && typeof drawing.chainage_m === "number"
        ? stationLabel(drawing.chainage_m, stationInterval)
        : drawing.label,
    info: drawing.kind === "cross" ? drawing.label : "",
    confirmed: response.confirmed,
    quantityTable: response.quantity_table ?? null,
    hasPrev: index > 0,
    hasNext: index < drawings.length - 1,
  });

  const sendLoad = (drawing: CadDrawing, meta: DesignMeta) => {
    pendingLoad = { drawing, meta };
    if (!cadReady) return;
    frame.contentWindow?.postMessage(
      { type: CAD_LOAD_MESSAGE, drawing, meta },
      window.location.origin,
    );
    pendingLoad = undefined;
  };

  const loadDrawing = async (drawing: DesignDrawingItem, index: number) => {
    if (!projectId) return;
    highlightActive(drawing.id);
    const button = findButton(drawing.id);
    if (button) button.dataset.loading = "true";
    cadHost.dataset.loading = "true";
    try {
      const response = await fetchDesignDrawing(projectId, drawing.id);
      currentDrawing = drawing;
      currentIndex = index;
      currentConfirmed = response.confirmed;
      confirmButton.disabled = response.confirmed;
      updateInfoPanel(drawing, response);
      sendLoad(response.drawing, buildMeta(drawing, response, index));
    } catch (error) {
      cadHost.dataset.loading = "false";
      cadHost.dataset.error =
        error instanceof Error ? error.message : "CAD 도면을 불러오지 못했습니다.";
    } finally {
      if (button) button.dataset.loading = "false";
    }
  };

  const selectDrawing = (drawing: DesignDrawingItem) => {
    void loadDrawing(drawing, drawings.indexOf(drawing));
  };

  const navigateDrawing = (direction: "prev" | "next") => {
    if (currentIndex < 0) return;
    const target = direction === "prev" ? currentIndex - 1 : currentIndex + 1;
    if (target < 0 || target >= drawings.length) return;
    void loadDrawing(drawings[target], target);
  };

  const requestCadDrawing = (): Promise<SaveResult> =>
    new Promise((resolve, reject) => {
      resolveSave = resolve;
      frame.contentWindow?.postMessage({ type: CAD_SAVE_REQUEST_MESSAGE }, window.location.origin);
      window.setTimeout(() => {
        if (!resolveSave) return;
        resolveSave = undefined;
        reject(new Error("CAD 저장 응답 시간이 초과되었습니다."));
      }, 5000);
    });

  async function confirmCurrentDrawing(): Promise<void> {
    if (!projectId || !currentDrawing) return;
    showLoadingOverlay();
    try {
      const saved = await requestCadDrawing();
      const result = await confirmDesignDrawing(
        projectId,
        currentDrawing.id,
        saved.drawing,
        currentDrawing.kind === "cross" ? (saved.quantityTable ?? null) : null,
      );
      currentConfirmed = true;
      currentDrawing.confirmed = true;
      confirmButton.disabled = true;
      const button = findButton(currentDrawing.id);
      if (button) button.dataset.confirmed = "true";
      // 확정 시 재계산된 확정 단면적으로 지반/계획 정보 패널을 갱신한다.
      if (currentDrawing.kind === "cross") {
        const infoTitle =
          typeof currentDrawing.chainage_m === "number"
            ? stationLabel(currentDrawing.chainage_m, stationInterval)
            : currentDrawing.label;
        infoPanelHost.replaceChildren(buildDesignInfoPanel(infoTitle, result.design ?? null));
      }
      showToast("현재 도면을 확정하고 저장했습니다.", "success");
      if (result.all_confirmed) {
        allDrawingsConfirmed = true;
        goToWorkflowStage(projectId, WORKFLOW_STEP_ROUTES[6]);
      }
    } catch (error) {
      showToast(
        error instanceof Error ? error.message : "현재 도면을 확정하지 못했습니다.",
        "error",
      );
    } finally {
      hideLoadingOverlay();
    }
  }

  const invalidateCurrentDrawing = async () => {
    if (!projectId || !currentDrawing) return;
    const wasConfirmed = currentConfirmed;
    currentConfirmed = false;
    allDrawingsConfirmed = false;
    currentDrawing.confirmed = false;
    confirmButton.disabled = false;
    const button = findButton(currentDrawing.id);
    if (button) button.dataset.confirmed = "false";
    if (wasConfirmed) {
      try {
        await invalidateDesignDrawing(projectId, currentDrawing.id);
      } catch (error) {
        showToast(
          error instanceof Error ? error.message : "도면 확정 상태를 되돌리지 못했습니다.",
          "error",
        );
      }
    }
  };

  window.addEventListener("message", (event: MessageEvent<unknown>) => {
    if (event.origin !== window.location.origin || event.source !== frame.contentWindow) return;
    const message = event.data as {
      type?: string;
      detail?: string;
      drawing?: CadDrawing;
      quantityTable?: QuantityTable | null;
      direction?: "prev" | "next";
    };
    if (message.type === CAD_READY_MESSAGE) {
      cadReady = true;
      if (pendingLoad) sendLoad(pendingLoad.drawing, pendingLoad.meta);
    } else if (message.type === CAD_LOADED_MESSAGE) {
      cadHost.dataset.loading = "false";
    } else if (message.type === CAD_ERROR_MESSAGE) {
      cadHost.dataset.error = message.detail ?? "CAD 도면을 표시하지 못했습니다.";
    } else if (message.type === CAD_CHANGED_MESSAGE) {
      void invalidateCurrentDrawing();
    } else if (message.type === CAD_NAVIGATE_MESSAGE && message.direction) {
      navigateDrawing(message.direction);
    } else if (message.type === CAD_SAVE_RESPONSE_MESSAGE && message.drawing && resolveSave) {
      const resolve = resolveSave;
      resolveSave = undefined;
      resolve({ drawing: message.drawing, quantityTable: message.quantityTable ?? null });
    }
  });

  const drawingPanel = buildDrawingSidePanel(
    drawings,
    stationInterval,
    selectDrawing,
    drawingError,
  );
  drawingListEl = drawingPanel;
  const confirmActions = document.createElement("div");
  // 하단 고정은 공용 ui-sidebar-actions로 통일 — 사이드 본문이 [스크롤 영역][액션 줄]로
  // 쪼개지고 액션 줄은 스크롤 밖에 남는다(2026-08-18 사용자 지시, B04~B08 공통).
  confirmActions.className = "b08-drawing-actions ui-sidebar-actions";
  confirmActions.append(confirmButton);

  drawingPanel.append(infoPanelHost, confirmActions);

  const layout = createWorkflowLayout({
    title: L("B08_Design_Title"),
    steps: workflowSteps(),
    activeStep: 5,
    leftPanel: drawingPanel,
    mainContent: cadHost,
    stages: workflowState?.stages,
    currentStage: workflowState?.current_stage,
    routes: WORKFLOW_STEP_ROUTES,
    onStepClick: (stepIndex) => {
      if (!projectId) return;
      if (stepIndex > 5 && !allDrawingsConfirmed) {
        showToast("모든 설계 도면을 확정한 뒤 다음 단계로 이동할 수 있습니다.", "warning");
        return;
      }
      goToWorkflowStage(projectId, WORKFLOW_STEP_ROUTES[stepIndex]);
    },
  });
  layout.root.classList.add("b08-design-layout");
  root.replaceChildren(layout.root);

  // 페이지 진입 시 첫 도면(종단도)을 자동 선택 — 빈 CAD 화면 방지.
  // CAD가 아직 준비 전이면 sendLoad가 pendingLoad로 대기했다가 ready 시 전송한다.
  if (drawings.length > 0) {
    void loadDrawing(drawings[0], 0);
  }
}