/* =============================================================================
 * D03_PlanAnalysis_UI_Page.ts
 * D 예정노선 2단계 노선분석(요구서 389 3장 6~13 · PLAN 562-3 · 563-1) — B05~B09 틀(`mountGroupStep`).
 *
 *   메인 = 평면(바탕 겹 켜고 끔 — 위성 · 등고선 · 세류 · 지적 · 도로 · 급경사 + 그은 선 · 측점 · 구역 마크) + 도구 여섯.
 *   좌 = 지형(범위를 카카오 지도에 먼저 보임 → [이 범위 받기] · [범위 밖 더 받기]는 선이 받은 범위 밖일 때만) ·
 *        그리기(본선 · 갈래 · 구역 마크 · 제약 칸) · 구역 · 연도(조각마다 연도) · [저장] [초기화].
 *
 * 데이터 3층(CLAUDE.md 5장) — 긋기 · 마크 · 연도 = 캐시(`d03-plan` {version: 2, network}) · [저장] =
 *   PUT plan/network(서버가 길이 · 측점 · 조각 · 연도 행을 다시 셈 · 응답으로 바꿈) · [초기화] = 빈 선 PUT.
 *   되돌리기 · 다시하기 = 이 화면 스택(걸음 = `commit` 한 번). 화면 전체 잠금 = [저장] · [초기화]만.
 *   공유 회사(산림청 아님) = 보기만 — 긋기 · 받기 · [저장] 없음.
 * ========================================================================== */

import "./D03_PlanAnalysis_UI_Style.css";
import { ROUTES } from "@config/config_frontend";
import { attachCollapsible, createPanelCard } from "@ui/ui_template_collapsible";
import { createInputField, createSelectField } from "@ui/ui_template_input";
import { editMap } from "@ui/ui_template_kakao_map";
import { askConfirm, openModal } from "@ui/ui_template_modal";
import { createProgressBar } from "@ui/ui_template_progress";
import { createText } from "@ui/ui_template_text";
import {
  createButton,
  hideLoadingOverlay,
  showLoadingOverlay,
  showToast,
} from "@ui/ui_template_elements";
import { clearState, readState, writeState } from "../A00_Common/b_page_state";
import { currentProjectId } from "../A00_Common/b_project_switch";
import { mountGroupStep } from "../A00_Common/group_workflow";
import { fetchSessionUser } from "../A06_Login/A06_Login_Api_Fetch";
import { heightAt as gridHeightAt } from "../common_util/common_util_surface_sampler";
import { stationLabel } from "../common_util/common_util_station";
import {
  fetchPlanNetwork,
  fetchPlanProgress,
  fetchPlanSurface,
  fetchTerrainExtent,
  savePlanNetwork,
  startTerrain,
  type PlanJob,
  type PlanNetworkView,
  type PlanSurface,
  type TerrainExtent,
} from "./D03_PlanAnalysis_Api";
import { openPlan3d } from "./D03_PlanAnalysis_UI_3D";
import { createPlanDraw } from "./D03_PlanAnalysis_UI_Draw";
import { createPlanLayers } from "./D03_PlanAnalysis_UI_Layers";
import { createPlanMap, PLAN_STATION_INTERVAL_M } from "./D03_PlanAnalysis_UI_Map";
import { createPlanMeasure } from "./D03_PlanAnalysis_UI_Measure";
import { lineLength, stationChainages } from "./logic/D03_PlanAnalysis_Draw";
import {
  emptyNetwork,
  fromServer,
  lineName,
  marksOf,
  normalizePieces,
  setPieceYear,
  type PlanNetwork,
  type Vertex,
} from "./logic/D03_PlanAnalysis_Plan";

const POLL_MS = 1000;
/** 되돌리기 쌓는 수. */
const UNDO_MAX = 100;
/** 조각 연도 고를 수 — 사업연도 시작부터. */
const YEAR_SPAN = 10;
/** 캐시 꼴 판 — 옛 꼴(지점 · 갈래 고름)은 안 읽음. */
const DRAFT_VERSION = 2;

interface Draft {
  version: number;
  network: PlanNetwork;
}

const sleep = (ms: number): Promise<void> => new Promise((done) => setTimeout(done, ms));
const errorText = (error: unknown): string =>
  error instanceof Error ? error.message : String(error);
const station = (m: number): string => stationLabel(m, PLAN_STATION_INTERVAL_M, 1);

export async function renderD03PlanAnalysis(root: HTMLElement): Promise<void> {
  const projectId = currentProjectId();
  let editable = false;
  let start: Vertex = [0, 0];
  let end: Vertex = [0, 0];
  let epsg = 0;
  let yearStart = new Date().getFullYear();
  let network: PlanNetwork = emptyNetwork(start);
  let savedJson = "";
  let undoStack: PlanNetwork[] = [];
  let redoStack: PlanNetwork[] = [];
  let surface: PlanSurface | null = null;
  let have: [number, number, number, number] | null = null;
  let busy = false;
  let failed: string | null = null;
  let measuring = false;
  let lastSaveMs: number | null = null;

  const z = (x: number, y: number): number => (surface ? gridHeightAt(surface.grid, x, y) : NaN);
  const draw = createPlanDraw({
    base: () => ({ start, end }),
    network: () => network,
    heightAt: () => z,
    commit,
    onMode: () => {
      if (draw.mode() !== "idle") setMeasure(false);
      refresh();
    },
  });
  const measure = createPlanMeasure(() => z);
  const map = createPlanMap({
    onUndo: undo,
    onRedo: redo,
    on3d: open3d,
    onMeasure: () => setMeasure(!measuring),
  });
  const backdrop = createPlanLayers({
    projectId,
    map,
    points: () => [start, end, ...allVertices()],
  });
  map.root.append(backdrop.bar, backdrop.legend);
  const main = document.createElement("div");
  main.className = "d03-plan";
  main.append(map.root);

  const terrainText = createText("", "muted");
  terrainText.classList.add("d03-plan__hint");
  const bar = createProgressBar();
  bar.root.hidden = true;
  const extentButton = createButton({
    label: "지형 범위 보기",
    variant: "filled",
    size: 28,
    onClick: () => void openExtent([]),
  });
  const moreButton = createButton({
    label: "범위 밖 더 받기",
    variant: "filled",
    size: 28,
    onClick: () => void openExtent(allVertices()),
  });
  const terrainCard = createPanelCard("지형", false);
  terrainCard.append(terrainText, bar.root, extentButton, moreButton);
  const drawCard = createPanelCard("그리기", false);
  drawCard.append(draw.panel);
  const pieceList = document.createElement("div");
  pieceList.className = "d03-plan__pieces";
  const pieceCard = createPanelCard("구역 · 연도", false);
  pieceCard.append(pieceList);
  const saveButton = createButton({ label: "저장", variant: "filled", onClick: () => void save() });
  const resetButton = createButton({
    label: "초기화",
    variant: "ghost",
    onClick: () => void reset(),
  });
  const actions = document.createElement("div");
  actions.className = "ui-sidebar-actions";
  actions.append(saveButton, resetButton);
  const panel = document.createElement("div");
  panel.className = "ui-sidebar-panel d03-plan__panel";
  panel.append(terrainCard, drawCard, pieceCard, actions);
  attachCollapsible(panel);
  // 떠날 때(단계 아이콘 · [<] [>] · 머리 메뉴 · 뒤로) 고친 선이 있으면 공용 물음 [취소][폐기][저장](572-3)
  mountGroupStep(root, ROUTES.D03_PLAN_ANALYSIS, {
    mainContent: main,
    leftPanel: panel,
    dirty: () => editable && dirty(),
    save,
    discard: () => clearState("d03-plan", projectId),
  });
  root.querySelector(".ui-workflow-layout")?.classList.add("d03-plan-layout");

  const allVertices = (): Vertex[] => network.lines.flatMap((line) => line.vertices);
  const dirty = (): boolean => JSON.stringify(network) !== savedJson;
  const keepDraft = (): void =>
    dirty()
      ? writeState("d03-plan", { version: DRAFT_VERSION, network } satisfies Draft, projectId)
      : clearState("d03-plan", projectId);

  /** 한 걸음 — 조각을 맞춰 넣고 되돌리기에 쌓음 · 캐시. */
  function commit(next: PlanNetwork): void {
    undoStack = [...undoStack.slice(1 - UNDO_MAX), network];
    redoStack = [];
    network = normalizePieces(next, yearStart);
    keepDraft();
    refresh();
  }

  function undo(): void {
    const last = undoStack.pop();
    if (!last) return;
    redoStack.push(network);
    network = last;
    keepDraft();
    refresh();
  }

  function redo(): void {
    const next = redoStack.pop();
    if (!next) return;
    undoStack.push(network);
    network = next;
    keepDraft();
    refresh();
  }

  function setMeasure(on: boolean): void {
    if (on === measuring) return;
    measuring = on;
    measure.clear();
    if (on) draw.setMode("idle");
    map.setLayers([...backdrop.layers, draw.layer, ...(measuring ? [measure.layer] : [])]);
    refresh();
  }

  /** 꺾임점이 받은 범위 밖인가(받은 범위 없음 = 밖 아님 — 그땐 [지형 범위 보기]). */
  const outside = (): boolean =>
    !!have &&
    allVertices().some(([x, y]) => x < have![0] || x > have![2] || y < have![1] || y > have![3]);

  function refresh(): void {
    draw.sync();
    map.setTools({
      undo: editable && undoStack.length > 0,
      redo: editable && redoStack.length > 0,
      view3d: !!surface && network.lines.some((line) => line.vertices.length > 1),
      measure: measuring,
    });
    map.redraw();
    renderPieces();
    extentButton.hidden = !editable || busy || !!surface;
    moreButton.hidden = !editable || busy || !surface || !outside();
    if (!busy)
      terrainText.textContent = failed
        ? `지형 받기 실패 — ${failed}`
        : !surface
          ? "받은 지형 없음 — 범위를 보고 받으세요(미리보기 길이 · 기울기는 지형을 받은 뒤)."
          : outside()
            ? "그은 선이 받은 지형 밖으로 나갔습니다 — 더 받아야 기울기를 셉니다."
            : "받은 지형 안";
    if (failed && editable && !busy) extentButton.hidden = false;
    extentButton.querySelector(".ui-btn__label")!.textContent = failed
      ? "다시 받기"
      : "지형 범위 보기";
    saveButton.hidden = resetButton.hidden = !editable;
    saveButton.disabled = busy || !dirty();
  }

  function renderPieces(): void {
    const years = new Set(Array.from({ length: YEAR_SPAN }, (_, i) => yearStart + i));
    network.pieces.forEach((piece) => years.add(piece.year));
    const options = [...years].sort().map((year) => ({ value: String(year), text: `${year}년` }));
    const rows: HTMLElement[] = [];
    network.lines.forEach((line, index) => {
      const pieces = network.pieces.filter((piece) => piece.line === line.id);
      if (!pieces.length) return;
      const head = createText(
        `${lineName(index)} · ${lineLength(line.vertices).toFixed(1)} m`,
        "muted",
      );
      head.classList.add("d03-plan__piece-head");
      rows.push(head);
      for (const piece of pieces) {
        const row = document.createElement("div");
        row.className = "d03-plan__piece";
        row.dataset.piece = piece.id;
        const span = createText(
          `${station(piece.from_m)} ~ ${station(piece.to_m)} (${(piece.to_m - piece.from_m).toFixed(1)} m)`,
          "muted",
        );
        const pick = createSelectField({
          options,
          value: String(piece.year),
          size: 24,
          ariaLabel: "연도",
          disabled: !editable,
          onChange: (value) =>
            commit(setPieceYear(network, network.pieces.indexOf(piece), Number(value))),
        });
        row.append(span, pick.root);
        rows.push(row);
      }
    });
    if (!rows.length) rows.push(createText("선을 그으면 구역이 생깁니다.", "muted"));
    pieceList.replaceChildren(...rows);
  }

  /** 받기 전 범위를 카카오 지도에 보임 → [이 범위 받기]. */
  async function openExtent(extra: Vertex[]): Promise<void> {
    let extent: TerrainExtent;
    try {
      extent = await fetchTerrainExtent(projectId, null, extra);
    } catch (error) {
      return void showToast(`받을 범위를 읽지 못했습니다 — ${errorText(error)}`, "error");
    }
    const info = createText("", "muted");
    const kakao = editMap({
      onMove: () => undefined,
      hint: "받을 범위(빨강) · 받은 범위(초록) · 도엽(옅게)",
    });
    const show = (view: TerrainExtent): void => {
      const ring = (points: Array<[number, number]>): Array<[number, number]> =>
        [...points, points[0]].map(([lon, lat]) => [lat, lon]);
      const lines = [
        ring(view.box),
        ...(view.have ? [ring(view.have)] : []),
        ...view.sheets.map((s) => ring(s.ring)),
      ];
      const colors = [
        "#E60046",
        ...(view.have ? ["#16a34a"] : []),
        ...view.sheets.map(() => "#94a3b8"),
      ];
      kakao.set([], lines, colors);
      const newSheets = view.sheets.filter((sheet) => !sheet.stored).length;
      info.textContent =
        `여유 ${view.margin_m.toFixed(0)} m · 도엽 ${view.sheets.length}매(새로 ${newSheets}) · ` +
        `지형 칸 약 ${(view.cells / 1e6).toFixed(1)}백만` +
        (view.covered ? " · 이미 받은 범위 안" : "");
    };
    const margin = createInputField({
      label: "여유",
      type: "number",
      value: extent.margin_m.toFixed(0),
      unit: "m",
      size: 24,
    });
    const applyMargin = createButton({
      label: "다시 보기",
      variant: "ghost",
      size: 24,
      onClick: () =>
        void fetchTerrainExtent(projectId, Number(margin.input.value) || null, extra)
          .then((view) => show((extent = view)))
          .catch((error) => showToast(errorText(error), "error")),
    });
    const row = document.createElement("div");
    row.className = "d03-plan__row";
    row.append(margin.root, applyMargin);
    let close = (): void => undefined;
    const go = createButton({
      label: "이 범위 받기",
      variant: "filled",
      onClick: () => {
        close();
        void download(extent.margin_m, extra);
      },
    });
    ({ close } = openModal({
      title: "지형 받기 — 범위 미리보기",
      closeLabel: "닫기",
      width: "960px",
      dialogClass: "d03-plan__extent-modal",
      actions: [go],
      mount: (body) => {
        body.classList.add("d03-plan__extent");
        body.append(row, info, kakao.root);
        show(extent);
      },
    }));
  }

  async function download(marginM: number, extra: Vertex[]): Promise<void> {
    try {
      await startTerrain(projectId, marginM, extra);
    } catch (error) {
      // 이미 도는 일(다른 창)이면 그것을 지켜봄
      if (!/이미 돌고/.test(errorText(error))) return void showToast(errorText(error), "error");
    }
    await follow();
  }

  /** 도는 받기를 지켜보고 끝나면 지형 · 바탕을 다시 읽음. */
  async function follow(): Promise<void> {
    const job = await watch();
    if (!job || !root.isConnected) return;
    failed = job.error;
    await Promise.all([loadSurface(), backdrop.load()]);
    refresh();
  }

  /** 지형 받기를 끝날 때까지 지켜봄 — 진행은 지형 칸에. */
  async function watch(): Promise<PlanJob | null> {
    busy = true;
    bar.root.hidden = false;
    refresh();
    try {
      for (;;) {
        if (!root.isConnected) return null;
        const job = (await fetchPlanProgress(projectId)).terrain;
        bar.set(job.percent / 100);
        terrainText.textContent = `지형 받기 ${job.percent}% · ${job.message ?? ""}`;
        if (!job.running) {
          if (job.error) showToast(job.error, "error");
          return job;
        }
        await sleep(POLL_MS);
      }
    } catch (error) {
      showToast(`진행을 읽지 못했습니다 — ${errorText(error)}`, "error");
      return null;
    } finally {
      busy = false;
      bar.root.hidden = true;
      refresh();
    }
  }

  async function loadSurface(): Promise<void> {
    try {
      surface = await fetchPlanSurface(projectId);
      const extent = surface ? await fetchTerrainExtent(projectId, null, []) : null;
      have = extent?.have_m ?? null;
    } catch (error) {
      showToast(`지형면을 읽지 못했습니다 — ${errorText(error)}`, "error");
    }
  }

  /** 서버 응답 → 지금 값 · 저장본(빈 선 = 시점만). */
  function takeServer(view: PlanNetworkView): void {
    if (view.year_start) yearStart = view.year_start;
    const server = view.network;
    network =
      server && server.lines.length
        ? fromServer(server.lines, server.marks, server.pieces, yearStart)
        : emptyNetwork(start);
    if (server?.epsg) epsg = server.epsg;
    savedJson = JSON.stringify(network);
  }

  function serverBody(): Parameters<typeof savePlanNetwork>[1] {
    return { epsg, lines: network.lines, marks: marksOf(network), pieces: network.pieces };
  }

  /** [저장] — 서버가 다시 셈 · 실패면 그대로(캐시 남음). 참 = 저장됨. */
  async function save(): Promise<boolean> {
    draw.setMode("idle");
    showLoadingOverlay();
    try {
      const began = performance.now();
      takeServer(await savePlanNetwork(projectId, serverBody()));
      lastSaveMs = Math.round(performance.now() - began);
      clearState("d03-plan", projectId);
      undoStack = [];
      redoStack = [];
      refresh();
      showToast("예정노선을 저장했습니다.", "success");
      return true;
    } catch (error) {
      showToast(`저장하지 못했습니다 — ${errorText(error)}`, "error");
      return false;
    } finally {
      hideLoadingOverlay();
    }
  }

  /** [초기화] = 시점 · 종점만 남은 빈 선을 정본에. */
  async function reset(): Promise<void> {
    const ok = await askConfirm({
      title: "초기화",
      message:
        "그은 선 · 갈래 · 구역을 모두 지우고 시점 · 종점만 남깁니다. 저장된 노선도 바뀝니다.",
      okLabel: "초기화",
      danger: true,
    });
    if (!ok) return;
    draw.setMode("idle");
    showLoadingOverlay();
    try {
      takeServer(await savePlanNetwork(projectId, { epsg, lines: [], marks: [], pieces: [] }));
      clearState("d03-plan", projectId);
      undoStack = [];
      redoStack = [];
      refresh();
      showToast("시점 · 종점만 남겼습니다.", "success");
    } catch (error) {
      showToast(`초기화하지 못했습니다 — ${errorText(error)}`, "error");
    } finally {
      hideLoadingOverlay();
    }
  }

  function open3d(): void {
    if (!surface) return;
    const lines = network.lines
      .map((line, index) => ({
        name: lineName(index),
        line: line.vertices,
        stations: stationChainages(lineLength(line.vertices), PLAN_STATION_INTERVAL_M),
      }))
      .filter((item) => item.line.length > 1);
    openPlan3d(projectId, surface, lines);
  }

  // 검증 창구 — 꼴 · 미리보기 · 제약 · 화면 자리 · 재기 · 회전 · 저장 시간(ORCA 판정)
  (window as unknown as { __d03Plan?: unknown }).__d03Plan = {
    network: () => network,
    base: () => ({ start, end }),
    screenOf: map.screenOf,
    preview: draw.preview,
    constraint: draw.constraint,
    setConstraint: draw.setConstraint,
    mode: draw.mode,
    setMode: draw.setMode,
    measure: measure.result,
    rotationDeg: map.rotationDeg,
    history: () => ({ undo: undoStack.length, redo: redoStack.length }),
    dirty,
    saveMs: () => lastSaveMs,
    heightAt: z,
    layers: backdrop.state,
  };
  const onKey = (event: KeyboardEvent): void => {
    if (!root.isConnected) return window.removeEventListener("keydown", onKey);
    const typing = (event.target as HTMLElement | null)?.closest?.("input, textarea, select");
    if (typing || !editable) return;
    const key = event.key.toLowerCase();
    const ctrl = event.ctrlKey || event.metaKey;
    const handled =
      ctrl && key === "z" && !event.shiftKey
        ? (undo(), true)
        : ctrl && (key === "y" || (key === "z" && event.shiftKey))
          ? (redo(), true)
          : measuring && event.key === "Escape"
            ? (setMeasure(false), true)
            : !ctrl && draw.key(event);
    if (handled) {
      event.preventDefault();
      map.redraw();
    }
  };
  window.addEventListener("keydown", onKey);
  map.setLayers([...backdrop.layers, draw.layer]);

  try {
    editable = !!(await fetchSessionUser())?.is_forest_service;
    draw.setEditable(editable);
    const view = await fetchPlanNetwork(projectId);
    const base = view.base;
    if (!base.start || !base.end || !base.epsg) {
      terrainText.textContent = "시점 · 종점이 비었습니다 — 1단계(기준 지정)에서 정하세요.";
      return;
    }
    start = [base.start.x, base.start.y];
    end = [base.end.x, base.end.y];
    epsg = base.epsg;
    takeServer(view);
    const draft = readState<Draft>("d03-plan", projectId);
    if (draft?.version === DRAFT_VERSION && draft.network?.lines?.length) network = draft.network;
    map.update({ fit: [start, end, ...allVertices()] });
    refresh();
    await loadSurface();
    refresh();
    await backdrop.load();
    if ((await fetchPlanProgress(projectId)).terrain.running) await follow();
  } catch (error) {
    terrainText.textContent = `불러오지 못했습니다 — ${errorText(error)}`;
  }
}