/* =============================================================================
 * E04_Stab3D_UI_Page.ts
 * E04 안정성평가 3D 해석(요구 347-1 · 요구서 4-2 · 4-3 · PLAN 533-3) — B05~B09 틀(group_workflow).
 *   좌 = 구간 목록 · 탐색 설정(기본 · 고급 접힘) · [해석] · 진행률 · [끊기]
 *   가운데 = 평면 지도(셀별 최소 안전율 · 임계 체적) · [3D 보기](지표 + 노선면 + 임계 활동면)
 *   우 = 구간 결과(3D 최소 · 2D 최소(같은 구간 E03 측점 · 3D 와 같은 조건 안전율 최소) · 3D/2D 비 · 체적 · 방법)
 *   계산 = 서버 단독(POST …/stab/analyze3d · 뒤에서) · 화면은 값 · 그림만. 탐색 설정 = 캐시 `e04-settings`
 *   · 없으면 저장된 결과의 설정 · 결과 열쇠 = 구간 + 조건(건기 · 우기 따로 남음).
 * ========================================================================== */

import "./E04_Stab3D_UI_Style.css";
import { API_BASE_URL, ROUTES } from "@config/config_frontend";
import { attachCollapsible, createPanelCard } from "@ui/ui_template_collapsible";
import { createBadge } from "@ui/ui_template_badge";
import { createBanner } from "@ui/ui_template_banner";
import { createButton, el, showToast } from "@ui/ui_template_elements";
import { createEmpty } from "@ui/ui_template_empty";
import { createFloatPanel } from "@ui/ui_template_float_panel";
import { createKv, type KvRow } from "@ui/ui_template_kv";
import { createLegend } from "@ui/ui_template_flow_legend";
import { createListRow } from "@ui/ui_template_list_row";
import { t, type LocaleKey } from "@ui/ui_template_locale";
import { createProgressBar } from "@ui/ui_template_progress";
import { createSegment } from "@ui/ui_template_segment";
import { createSidePanels } from "@ui/ui_template_side_panels";
import { createText } from "@ui/ui_template_text";
import { readState, writeState } from "../A00_Common/b_page_state";
import { currentProjectId } from "../A00_Common/b_project_switch";
import { mountGroupStep } from "../A00_Common/group_workflow";
import { inferStationInterval, stationLabel } from "../common_util/common_util_station";
import { createPlanMap, type MapLayer, type StationPoint } from "./E04_Stab3D_UI_Map";
import { createView3D } from "./E04_Stab3D_UI_View3D";
import { buildSettingsCards, type Settings } from "./E04_Stab3D_UI_Settings";
import {
  FS_STEPS,
  VOLUME_STEPS,
  legendRows,
  fs2dOf,
  min2d,
  ratio3d2d,
  stepColor,
  type Result3d,
} from "./logic/E04_Stab3D_Raster";

interface SavedSummary {
  key: string;
  start_m: number;
  end_m: number;
  f_min: number;
  volume: number;
  method: string;
  condition: string;
  stale: boolean;
}

interface Overview {
  editable: boolean;
  sections: { start_m: number; end_m: number }[];
  stations: StationPoint[];
  line: number[][];
  saved: SavedSummary[];
  defaults: Settings;
  max_section_m: number;
}

interface Progress {
  running: boolean;
  percent: number;
  message: string | null;
  error: string | null;
  cancelled: boolean;
  key: string | null;
}

const CONDITIONS = ["dry", "wet"] as const;
const rangeKey = (start: number, end: number): string => `${start.toFixed(2)}_${end.toFixed(2)}`;
const sectionKey = (start: number, end: number, condition: string): string =>
  `${rangeKey(start, end)}_${condition}`;

async function api<T>(path: string, init?: RequestInit): Promise<T> {
  const response = await fetch(`${API_BASE_URL}${path}`, {
    credentials: "include",
    headers: { "Content-Type": "application/json" },
    ...init,
  });
  const body = (await response.json().catch(() => ({}))) as T & { detail?: unknown };
  if (!response.ok) {
    const detail = body.detail;
    throw new Error(typeof detail === "string" ? detail : `HTTP ${response.status}`);
  }
  return body;
}

/** E03 2D 측점 줄(GET …/stab/result2d · fs_by_condition · min = 조건별) — 없으면 빈 목록 */
type Station2d = Parameters<typeof fs2dOf>[0] & { chainage_m: number };

async function fetch2d(projectId: string): Promise<Station2d[]> {
  try {
    const body = await api<{ stations?: Station2d[] }>(`/projects/${projectId}/stab/result2d`);
    return (body.stations ?? []).map((s) => ({ ...s, chainage_m: Number(s.chainage_m) }));
  } catch {
    return [];
  }
}

/** 안내 글 한 줄 — 걸이 이름(`e04-hint` 같은)만 얹음 */
function note(text: string, hook: string): HTMLElement {
  const node = createText(text, "muted");
  node.classList.add(hook);
  return node;
}

function emptyBox(text: string): HTMLElement {
  const node = createEmpty({ text, small: true });
  node.classList.add("e04-empty");
  return node;
}

/** 지도 범례 — 떠 있는 판(머리 = 제목) 안에 범례 부품 */
function legend(layer: MapLayer): HTMLElement {
  const rows = layer === "fs" ? legendRows(FS_STEPS, 1) : legendRows(VOLUME_STEPS, 0);
  const panel = createFloatPanel({
    title: t(layer === "fs" ? "E04_Legend_FS" : "E04_Legend_Volume"),
  });
  panel.root.classList.add("e04-legend");
  panel.body.append(
    createLegend(
      [...rows, { color: stepColor(FS_STEPS, null), label: t("E04_NoData") }].map((row) => ({
        label: row.label,
        color: row.color,
      })),
      { vertical: true },
    ),
  );
  return panel.root;
}

export function renderE04Stab3D(root: HTMLElement): void {
  const projectId = currentProjectId();
  const panel = el("div", { className: "ui-sidebar-panel e04-panel" });
  const main = el("div", { className: "e04-page" });
  mountGroupStep(root, ROUTES.E04_STAB_3D, { mainContent: main, leftPanel: panel });
  if (!projectId) return void main.append(emptyBox(t("E04_NoProject")));

  // ---- 가운데 ----
  const map = createPlanMap();
  const view3d = createView3D();
  view3d.root.hidden = true;
  let mode: "plan" | "3d" = "plan";
  let layer: MapLayer = "fs";
  const toggle = (labels: [LocaleKey, string][], onPick: (value: string) => void) => {
    const group = createSegment({
      options: labels.map(([key, value]) => ({ value, label: t(key) })),
      value: labels[0][1],
      size: 24,
      onChange: onPick,
    });
    group.root.classList.add("e04-toggle");
    return group.root;
  };
  const legendSlot = el("div", { className: "e04-legend-slot" });
  const paintLegend = (): void => legendSlot.replaceChildren(legend(layer));
  const stage = el("div", { className: "e04-stage" });
  stage.append(map.root, view3d.root, legendSlot);
  const toolbar = el("div", { className: "e04-toolbar" });
  toolbar.append(
    toggle(
      [
        ["E04_View_Plan", "plan"],
        ["E04_View_3D", "3d"],
      ],
      (value) => {
        mode = value as "plan" | "3d";
        map.root.hidden = mode !== "plan";
        view3d.root.hidden = mode !== "3d";
        view3d.setActive(mode === "3d");
        if (mode === "3d") view3d.show(result, overview?.line ?? [], layer);
      },
    ),
    toggle(
      [
        ["E04_Layer_FS", "fs"],
        ["E04_Layer_Volume", "volume"],
      ],
      (value) => {
        layer = value as MapLayer;
        map.setLayer(layer);
        if (mode === "3d") view3d.show(result, overview?.line ?? [], layer, false);
        paintLegend();
      },
    ),
  );
  const center = el("div", { className: "e04-center" });
  center.append(toolbar, stage);
  paintLegend();

  // ---- 우 ----
  const resultBody = el("div", { className: "e04-result" });
  const side = createSidePanels({
    prefKey: "e04-stab3d-result",
    panels: [{ id: "result", title: t("E04_Result_Title"), body: resultBody }],
    defaultOpen: "result",
    defaultWidth: 320,
    follow: false,
  });
  const row = el("div", { className: "ui-side-panels-row e04-row" });
  row.append(center, side.root);
  main.append(row);

  // ---- 좌 ----
  const sectionList = el("div", { className: "e04-sections" });
  const sectionCard = createPanelCard(t("E04_Card_Sections"), false);
  const settings = buildSettingsCards();
  sectionCard.append(sectionList, settings.rangeRow);
  const progressBar = createProgressBar();
  const progressText = note("", "e04-progress__text");
  const cancelButton = createButton({
    label: t("E04_Cancel"),
    variant: "danger-ghost",
    size: "sm",
    onClick: () => void api(`/projects/${projectId}/stab/analyze3d/cancel`, { method: "POST" }),
  });
  const progressBox = el("div", { className: "e04-progress-box" });
  progressBox.append(progressBar.root, progressText, cancelButton);
  progressBox.hidden = true;
  const analyzeButton = createButton({
    label: t("E04_Analyze"),
    variant: "filled",
    onClick: () => void analyze(),
  });
  analyzeButton.disabled = true;
  const actions = el("div", { className: "ui-sidebar-actions" });
  actions.append(analyzeButton);
  const readOnly = note(t("E04_ReadOnly"), "e04-hint");
  readOnly.hidden = true;
  panel.append(
    note(t("E04_Hint"), "e04-hint"),
    readOnly,
    sectionCard,
    settings.basicCard,
    settings.advancedCard,
    progressBox,
    actions,
  );
  attachCollapsible(panel);

  // ---- 상태 ----
  let overview: Overview | null = null;
  let result: Result3d | null = null;
  let stations2d: Station2d[] = [];
  let running = false;
  /** 측점 글 = No.+거리(소수 한 자리) · 간격 = 측점 목록 추정 */
  const station = (chainage: number): string =>
    stationLabel(chainage, inferStationInterval(overview?.stations ?? []), 1);

  const remember = (): void => writeState("e04-settings", settings.read(), projectId);
  let shownKey = "";
  settings.onChange(() => {
    remember();
    const { start_m, end_m, condition } = settings.read();
    map.setRange(start_m, end_m);
    paintSections();
    if (shownKey !== sectionKey(start_m, end_m, condition)) void openResult();
  });

  function paintButtons(): void {
    const editable = Boolean(overview?.editable);
    analyzeButton.disabled = !editable || running || !overview;
    readOnly.hidden = !overview || editable;
  }

  function paintSections(): void {
    if (!overview) return;
    const { start_m, end_m, condition } = settings.read();
    const savedOf = new Map(overview.saved.map((s) => [s.key, s]));
    const items = new Map(overview.sections.map((x) => [rangeKey(x.start_m, x.end_m), x]));
    for (const s of overview.saved) {
      const key = rangeKey(s.start_m, s.end_m);
      if (!items.has(key)) items.set(key, { start_m: s.start_m, end_m: s.end_m });
    }
    sectionList.replaceChildren(
      ...[...items].map(([key, section]) => {
        const byCondition = CONDITIONS.map((c) => savedOf.get(`${key}_${c}`));
        const saved = savedOf.get(`${key}_${condition}`);
        const row = createListRow({
          label: `${station(section.start_m)} – ${station(section.end_m)}`,
          trailing: byCondition
            .flatMap((x) =>
              x
                ? [
                    `${t(`E04_Short_${x.condition}` as LocaleKey)} ${x.f_min.toFixed(2)}${
                      x.stale ? ` ${t("E04_Stale")}` : ""
                    }`,
                  ]
                : [],
            )
            .join(" · "),
          stripe: saved ? stepColor(FS_STEPS, saved.f_min) : "transparent",
          active: key === rangeKey(start_m, end_m),
          onClick: () => settings.setRange(section.start_m, section.end_m),
        });
        row.classList.add("e04-section");
        row.dataset.key = key;
        return row;
      }),
    );
  }

  function paintResult(): void {
    if (!result) {
      resultBody.replaceChildren(emptyBox(t("E04_Result_None")));
      return;
    }
    const s = result.summary;
    const f2d = min2d(
      stations2d.map((x) => ({ chainage_m: x.chainage_m, fs_min: fs2dOf(x, s.condition) })),
      s.start_m,
      s.end_m,
    );
    const ratio = ratio3d2d(s.f_min, f2d);
    const nearest = overview?.stations.reduce<StationPoint | null>(
      (best, x) =>
        !best || Math.abs(x.chainage_m - s.chainage_m) < Math.abs(best.chainage_m - s.chainage_m)
          ? x
          : best,
      null,
    );
    const rows: [LocaleKey, string, string?][] = [
      ["E04_Result_F3d", s.f_min.toFixed(3), stepColor(FS_STEPS, s.f_min)],
      [
        "E04_Result_Verdict",
        `${t(s.verdict === "ok" ? "E04_Verdict_ok" : "E04_Verdict_ng")} (${t(
          `E04_Condition_${s.condition}` as LocaleKey,
        )} ≥ ${s.reference_fs.toFixed(2)})`,
      ],
      ["E04_Result_F2d", f2d === null ? t("E04_No2D") : f2d.toFixed(3)],
      ["E04_Result_Ratio", ratio === null ? "-" : ratio.toFixed(3)],
      ["E04_Result_Volume", `${Math.round(s.volume).toLocaleString()} m³`],
      ["E04_Result_Method", t(`E04_MethodName_${s.method}` as LocaleKey)],
      ["E04_Result_Bishop", s.by_method.bishop.toFixed(3)],
      ["E04_Result_Janbu", s.by_method.janbu_corrected.toFixed(3)],
      ["E04_Result_Hovland", s.by_method.hovland.toFixed(3)],
      ["E04_Result_Where", station(nearest?.chainage_m ?? s.chainage_m)],
      ["E04_Result_Cells", s.cells.toLocaleString()],
      ["E04_Result_Columns", s.columns == null ? "-" : s.columns.toLocaleString()],
      ["E04_Result_Trials", s.trials.toLocaleString()],
      ["E04_Result_Time", `${result.elapsed_s.toFixed(1)} s`],
    ];
    const kv: KvRow[] = rows.map(([key, value, color]) => {
      const cell = document.createDocumentFragment();
      if (color) {
        const chip = el("i", { className: "e04-section__chip" });
        chip.style.background = color;
        cell.append(chip);
      }
      cell.append(value);
      if (key === "E04_Result_Columns" && s.few_columns) {
        cell.append(" ", createBadge(t("E04_Result_FewColumns"), "warning", { size: 18 }));
      }
      return {
        label: t(key),
        value: cell,
        ...(key === "E04_Result_Verdict" ? { ok: s.verdict === "ok" } : {}),
      };
    });
    const list = createKv(kv);
    list.classList.add("e04-result__list");
    list.querySelectorAll("dd").forEach((dd, i) => {
      dd.setAttribute("data-field", rows[i][0]);
      if (rows[i][0] === "E04_Result_Verdict") dd.classList.add(`is-${s.verdict}`);
    });
    const notes: HTMLElement[] = [];
    if (result.stale) {
      const warn = createBanner({ tone: "warning", text: t("E04_Result_Stale") });
      warn.classList.add("e04-warn");
      notes.push(warn);
    }
    notes.push(note(t("E04_Result_Note"), "e04-note"));
    resultBody.replaceChildren(list, ...notes);
  }

  const currentKey = (): string => {
    const { start_m, end_m, condition } = settings.read();
    return sectionKey(start_m, end_m, condition);
  };

  async function openResult(): Promise<void> {
    const key = currentKey();
    shownKey = key;
    const saved = overview?.saved.some((s) => s.key === key);
    result = saved
      ? await api<Result3d>(`/projects/${projectId}/stab/result3d?key=${key}`).catch(() => null)
      : null;
    if (key !== currentKey()) return; // 그새 바뀜
    map.setResult(result);
    if (mode === "3d") view3d.show(result, overview?.line ?? [], layer);
    paintResult();
  }

  async function refresh(): Promise<void> {
    overview = await api<Overview>(`/projects/${projectId}/stab/result3d`);
    paintButtons();
    paintSections();
  }

  async function poll(): Promise<void> {
    while (root.isConnected) {
      const p = await api<Progress>(`/projects/${projectId}/stab/progress3d`).catch(() => null);
      if (!p) break;
      running = p.running;
      progressBox.hidden = !p.running;
      progressBar.set(p.percent / 100);
      progressText.replaceChildren(`${t("E04_Running")} ${p.percent}% · ${p.message ?? ""}`);
      paintButtons();
      if (!p.running) {
        if (p.error) showToast(p.error, "error");
        else if (p.cancelled) showToast(t("E04_Cancelled"), "info");
        else showToast(t("E04_Done"), "success");
        await refresh();
        await openResult();
        return;
      }
      await new Promise((resolve) => setTimeout(resolve, 700));
    }
  }

  async function analyze(): Promise<void> {
    const values = settings.read();
    const { start_m, end_m, condition, ...search } = values;
    try {
      const body = await api<{ status: string }>(`/projects/${projectId}/stab/analyze3d`, {
        method: "POST",
        body: JSON.stringify({ start_m, end_m, condition, search }),
      });
      if (body.status === "cached") {
        showToast(t("E04_Cached"), "info");
        await openResult();
        return;
      }
      running = true;
      paintButtons();
      progressBox.hidden = false;
      void poll();
    } catch (error) {
      showToast(error instanceof Error ? error.message : String(error), "error");
    }
  }

  // ---- 처음 ----
  void (async () => {
    try {
      await refresh();
    } catch (error) {
      main.replaceChildren(emptyBox(error instanceof Error ? error.message : String(error)));
      return;
    }
    const ov = overview!;
    settings.setDefaults(ov.defaults, ov.max_section_m);
    const cached = readState<Settings>("e04-settings", projectId);
    const first = ov.saved[0] ?? ov.sections[0];
    settings.write(
      cached ?? {
        ...ov.defaults,
        start_m: first?.start_m ?? 0,
        end_m: first?.end_m ?? 100,
        condition: ov.saved[0]?.condition ?? "dry",
      },
    );
    map.setRoute(ov.line, ov.stations);
    const { start_m, end_m } = settings.read();
    map.setRange(start_m, end_m);
    paintSections();
    stations2d = await fetch2d(projectId);
    await openResult();
    // 캐시가 없으면 저장된 결과의 탐색 설정을 되살림
    const opened = result as Result3d | null; // openResult 가 바꿈(흐름 좁힘 풀기)
    if (!cached && opened?.settings) {
      settings.write(opened.settings as Partial<Settings>);
      remember();
    }
    const p = await api<Progress>(`/projects/${projectId}/stab/progress3d`).catch(() => null);
    if (p?.running) void poll();
  })();

  // 떠날 때 — WebGL · 관찰자 정리
  const leave = new MutationObserver(() => {
    if (root.isConnected && main.isConnected) return;
    leave.disconnect();
    map.dispose();
    view3d.dispose();
  });
  leave.observe(document.body, { childList: true, subtree: true });
}