/* =============================================================================
 * E03_StabSection_UI_Page.ts
 * E03 2D 측점 해석(요구서 345 4-3 · 요구 347 · 351 · PLAN 532-3) — B05~B09 틀(group_workflow).
 *   좌 = 측점 목록(조건 · 정렬 · N.G 만 · 대표 단면 별) · [해석] · [3D 보기] · [대표 단면 저장]
 *   위 = 평면 위험 띠 · 가운데 = 횡단(임계면 · 등안전율 · 후보 · 절편) · 우 = 결과 · 절편표 · 자유물체도 · 그래프
 *   계산 = 서버 단독([해석] → POST …/stab/analyze2d · 잠금판 진행률 = GET …/stab/progress) ·
 *   대표 단면 켬/끔 = sessionStorage 캐시 → [대표 단면 저장] = PUT(자동저장 없음).
 * ========================================================================== */

import "./E03_StabSection_UI_Style.css";
import { API_BASE_URL, CURRENT_PROJECT_ID_KEY, ROUTES } from "@config/config_frontend";
import {
  createButton,
  createSelectField,
  el,
  hideLoadingOverlay,
  setLoadingOverlayProgress,
  showLoadingOverlay,
  showToast,
} from "@ui/ui_template_elements";
import { t, type LocaleKey } from "@ui/ui_template_locale";
import { mountGroupStep } from "../A00_Common/group_workflow";
import { buildList } from "./E03_StabSection_UI_List";
import { buildPlan } from "./E03_StabSection_UI_Plan";
import { buildResult } from "./E03_StabSection_UI_Result";
import {
  buildLegends,
  createSectionCanvas,
  type SectionToggles,
} from "./E03_StabSection_UI_Section";
import { openView3d } from "./E03_StabSection_UI_View3D";
import type {
  Analysis,
  Condition,
  SectionView,
  SortMode,
  StationRow,
} from "./logic/E03_StabSection_Logic";

interface Result2d {
  status: "ok" | "none";
  fresh: boolean;
  editable: boolean;
  running: boolean;
  conditions: Condition[];
  computed_at?: string;
  summary?: Record<string, unknown>;
  stations: StationRow[];
}

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

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) {
    throw new Error(typeof body.detail === "string" ? body.detail : `HTTP ${response.status}`);
  }
  return body;
}

const repKey = (projectId: string): string => `e03_representative_cache:${projectId}`;
const sleep = (ms: number): Promise<void> => new Promise((r) => setTimeout(r, ms));

function checkbox(label: string, checked: boolean, onChange: (v: boolean) => void): HTMLElement {
  const input = el("input", { attrs: { type: "checkbox" } });
  input.checked = checked;
  input.addEventListener("change", () => onChange(input.checked));
  return el("label", { className: "e03-check", children: [input, label] });
}

export function renderE03StabSection(root: HTMLElement): void {
  const projectId = localStorage.getItem(CURRENT_PROJECT_ID_KEY);
  const main = el("div", { className: "e03-page" });
  const panel = el("div", { className: "ui-sidebar-panel e03-panel" });
  mountGroupStep(root, ROUTES.E03_STAB_SECTION, { mainContent: main, leftPanel: panel });
  if (!projectId)
    return void main.append(el("p", { className: "e03-empty", text: t("E03_NoProject") }));
  const pid: string = projectId;
  const base = `/projects/${pid}/stab`;

  let result: Result2d | null = null;
  const sections = new Map<string, SectionView>();
  let condition: Condition = "dry";
  let sort: SortMode = "chainage";
  let ngOnly = false;
  let active: string | null = null;
  let side: string | null = null;
  let picked: number | null = null;
  const toggles: SectionToggles = { map: true, centers: false, candidates: true };
  let repCache: Record<string, boolean | null> = JSON.parse(
    sessionStorage.getItem(repKey(pid)) ?? "{}",
  );

  // ---- 좌측 ----
  const condField = createSelectField({
    label: t("E03_Condition"),
    options: [],
    compact: true,
    onChange: (v) => {
      condition = v as Condition;
      side = null;
      picked = null;
      paint();
    },
  });
  const sortField = createSelectField({
    label: t("E03_Sort"),
    options: [
      { value: "chainage", text: t("E03_Sort_Chainage") },
      { value: "fs", text: t("E03_Sort_Fs") },
    ],
    compact: true,
    onChange: (v) => {
      sort = v as SortMode;
      paintList();
    },
  });
  const ngBox = checkbox(t("E03_NgOnly"), false, (v) => {
    ngOnly = v;
    paintList();
  });
  const status = el("p", { className: "e03-muted", attrs: { "data-role": "status" } });
  const listHost = el("div", {
    className: "e03-panel",
    attrs: { style: "flex: 1 1 auto; min-height: 0" },
  });
  const analyzeButton = createButton({
    label: t("E03_Analyze"),
    variant: "filled",
    onClick: () => void analyze(),
  });
  const view3dButton = createButton({
    label: t("E03_View3d"),
    variant: "ghost",
    onClick: () => void show3d(),
  });
  const repButton = createButton({
    label: t("E03_RepSave"),
    variant: "ghost",
    onClick: () => void saveRep(),
  });
  const controls = el("div", { className: "e03-panel__row" });
  controls.append(condField.root, sortField.root);
  const actions = el("div", { className: "ui-sidebar-actions" });
  actions.append(repButton, view3dButton, analyzeButton);
  panel.append(controls, ngBox, status, listHost, actions);

  // ---- 본문 ----
  const planHost = el("div");
  const toolbar = el("div", { className: "e03-card__head" });
  const sectionCard = el("div", { className: "e03-card" });
  const legendHost = el("div");
  const canvas = createSectionCanvas((i) => {
    picked = i;
    paintSection();
  });
  sectionCard.append(toolbar, canvas.root, legendHost);
  const resultHost = el("div", { className: "e03-result", attrs: { style: "min-height: 0" } });
  const body = el("div", { className: "e03-body" });
  body.append(sectionCard, resultHost);
  main.append(planHost, body);

  const repOf = (row: StationRow): { on: boolean; user: boolean | null } => {
    const server = row.representative ?? { auto: [], user: null, on: false };
    if (!(row.key in repCache)) return { on: server.on, user: server.user };
    const user = repCache[row.key];
    return { on: user === null ? server.auto.length > 0 : user, user };
  };
  const repDirty = (): boolean => Object.keys(repCache).length > 0;

  const currentRow = (): StationRow | undefined => result?.stations.find((r) => r.key === active);

  /** 고른 측점 · 조건의 비탈 — 고른 게 없으면 안전율 가장 낮은 쪽 */
  const currentAnalysis = (view: SectionView): Analysis | null => {
    const list = view.analyses.filter((a) => a.condition === condition);
    if (!list.length) return null;
    const found = side ? list.find((a) => a.side === side) : null;
    if (found) return found;
    const worst = list
      .slice()
      .sort((a, b) => (a.critical?.fs ?? Infinity) - (b.critical?.fs ?? Infinity))[0];
    side = worst.side;
    return worst;
  };

  const paintStatus = (): void => {
    const lines: string[] = [];
    if (!result) lines.push(t("E03_Loading"));
    else if (result.status === "none") lines.push(t("E03_NotYet"));
    else {
      lines.push(`${t("E03_Computed")} ${result.computed_at ?? ""}`);
      if (!result.fresh) lines.push(t("E03_Stale"));
    }
    if (result && !result.editable) lines.push(t("E03_ReadOnly"));
    if (repDirty()) lines.push(t("E03_RepUnsaved"));
    status.textContent = lines.join("\n");
    analyzeButton.disabled = !result?.editable;
    repButton.disabled = !result?.editable || !repDirty();
    view3dButton.disabled = result?.status !== "ok";
  };

  const paintList = (): void => {
    if (!result) return;
    listHost.replaceChildren(
      buildList(
        {
          rows: result.stations,
          conditions: result.conditions,
          condition,
          sort,
          ngOnly,
          active,
          representative: repOf,
          editable: result.editable,
        },
        (key) => void select(key),
        (key) => {
          const row = result!.stations.find((r) => r.key === key)!;
          const now = repOf(row).on;
          const auto = (row.representative?.auto.length ?? 0) > 0;
          // 자동과 같아지면 사용자 값 지움(null) — 서버 값과 같으면 캐시에서 뺌
          const next = !now === auto ? null : !now;
          if (next === (row.representative?.user ?? null)) delete repCache[key];
          else repCache[key] = next;
          sessionStorage.setItem(repKey(pid), JSON.stringify(repCache));
          paintList();
          paintStatus();
        },
      ),
    );
  };

  const paintSection = (): void => {
    const view = active ? sections.get(active) : undefined;
    toolbar.replaceChildren();
    resultHost.replaceChildren();
    legendHost.replaceChildren();
    if (!view) {
      canvas.render(null);
      const text = result?.status === "ok" ? t("E03_PickStation") : t("E03_NotYet");
      resultHost.append(
        el("div", { className: "e03-card", children: [el("p", { className: "e03-empty", text })] }),
      );
      return;
    }
    const analysis = currentAnalysis(view);
    const sides = view.analyses.filter((a) => a.condition === condition);
    const sideField = createSelectField({
      options: sides.map((a) => ({
        value: a.side,
        text: `${t(a.side === "left" ? "E03_Left" : "E03_Right")} · ${t(a.role === "cut" ? "E03_Cut" : "E03_Fill")}`,
      })),
      value: analysis?.side,
      compact: true,
      ariaLabel: t("E03_Side"),
      onChange: (v) => {
        side = v;
        picked = null;
        paintSection();
      },
    });
    const title = el("h3", {
      className: "e03-card__title",
      text: `${view.label ?? view.key} · ${t(`E03_Cond_${condition}` as LocaleKey)}`,
    });
    const flags = el("div", { className: "e03-panel__row" });
    flags.append(
      checkbox(t("E03_Show_Map"), toggles.map, (v) => ((toggles.map = v), paintSection())),
      checkbox(
        t("E03_Show_Centers"),
        toggles.centers,
        (v) => ((toggles.centers = v), paintSection()),
      ),
      checkbox(
        t("E03_Show_Candidates"),
        toggles.candidates,
        (v) => ((toggles.candidates = v), paintSection()),
      ),
    );
    toolbar.append(title, sideField.root, flags);
    const draw = { view, analysis, toggles, picked };
    canvas.render(draw);
    legendHost.append(
      buildLegends(draw),
      el("p", { className: "e03-muted", text: t("E03_NoWalls") }),
    );
    resultHost.append(
      buildResult(view, analysis, picked, (i) => {
        picked = i;
        paintSection();
      }),
    );
  };

  const paintPlan = (): void => {
    planHost.replaceChildren(
      result ? buildPlan(result.stations, condition, active, (key) => void select(key)) : el("div"),
    );
  };

  function paint(): void {
    paintStatus();
    paintList();
    paintPlan();
    paintSection();
  }

  async function select(key: string): Promise<void> {
    if (active !== key) picked = null;
    active = key;
    paintList();
    paintPlan();
    if (result?.status === "ok" && !sections.has(key) && !currentRow()?.error) {
      try {
        sections.set(key, await api<SectionView>(`${base}/section/${encodeURIComponent(key)}`));
      } catch (error) {
        showToast(error instanceof Error ? error.message : t("Common_Status_Error"), "error");
      }
    }
    if (active === key) paintSection();
  }

  async function load(): Promise<void> {
    result = await api<Result2d>(`${base}/result2d`);
    sections.clear();
    const conds = result.conditions;
    if (!conds.includes(condition)) condition = conds[0] ?? "dry";
    condField.setOptions(
      conds.map((c) => ({ value: c, text: t(`E03_Cond_${c}` as LocaleKey) })),
      condition,
    );
    const keys = result.stations.map((r) => r.key);
    repCache = Object.fromEntries(Object.entries(repCache).filter(([k]) => keys.includes(k)));
    if (!active || !keys.includes(active)) {
      // 처음 = 그 조건 가장 낮은 안전율 측점
      const worst = result.stations
        .filter((r) => r.min[condition] !== null && r.min[condition] !== undefined)
        .sort((a, b) => (a.min[condition] as number) - (b.min[condition] as number))[0];
      active = worst?.key ?? keys[0] ?? null;
    }
    paint();
    if (active) await select(active);
    if (result.running) await watch();
  }

  /** 잠금판 + 진행률 — 끝나면 다시 읽음 */
  async function watch(): Promise<void> {
    showLoadingOverlay();
    try {
      for (;;) {
        const p = await api<Progress>(`${base}/progress`);
        setLoadingOverlayProgress(
          p.percent / 100,
          `${t("E03_Analyzing")} ${p.percent}% · ${p.message}`,
        );
        if (!p.running) {
          if (p.error) showToast(p.error, "error");
          else showToast(t("E03_Done"), "success");
          break;
        }
        await sleep(1000);
      }
    } finally {
      hideLoadingOverlay();
    }
    await load();
  }

  async function analyze(): Promise<void> {
    try {
      const response = await api<{ status: string }>(`${base}/analyze2d`, { method: "POST" });
      if (response.status === "fresh") {
        showToast(t("E03_Fresh"), "info");
        await load();
        return;
      }
      await watch();
    } catch (error) {
      showToast(error instanceof Error ? error.message : t("Common_Status_Error"), "error");
    }
  }

  async function saveRep(): Promise<void> {
    try {
      const overrides: Record<string, boolean | null> = {};
      for (const row of result?.stations ?? []) {
        const user = row.key in repCache ? repCache[row.key] : (row.representative?.user ?? null);
        if (user !== null) overrides[row.key] = user;
      }
      await api(`${base}/representative`, { method: "PUT", body: JSON.stringify({ overrides }) });
      repCache = {};
      sessionStorage.removeItem(repKey(pid));
      showToast(t("E03_RepSaved"), "success");
      await load();
    } catch (error) {
      showToast(error instanceof Error ? error.message : t("Common_Status_Error"), "error");
    }
  }

  async function show3d(): Promise<void> {
    if (!result) return;
    try {
      const data = await api<Parameters<typeof openView3d>[0]>(`${base}/corridor3d`);
      await openView3d(data, result.stations, condition, t(`E03_Cond_${condition}` as LocaleKey));
    } catch (error) {
      showToast(error instanceof Error ? error.message : t("Common_Status_Error"), "error");
    }
  }

  paintStatus();
  load().catch((error) => {
    status.textContent = error instanceof Error ? error.message : t("Common_Status_Error");
  });
}