/* =============================================================================
 * B06_Section_Cross_Save.ts
 * [저장] · [확정] 서버 횡단 한 바퀴(PLAN 511-B B-4 · 서버 Node `cross.enforce`) — 저장 입력으로 모든 측점 설계선
 * 다시 냄 → 미교차 넓힘(DTM 격자) → 포장 구간 → 세월교 노면 하강. 차례 · 승계 · 입력 = 파이썬 그대로.
 *
 *   ⚠ ① 짝 — `B06_Section_Router_Design.py` `enforce_design_lines` · `enforce_pavement_ranges` ·
 *     `enforce_ford_surface_drops` + `B06_Section_Engine_SampleExtend.py` `extend_unclosed_sections`
 *     (서버 `_enforce_stored_designs` 차례 · DTM 아닌 지표면은 파이썬 길) · 저장분 입력 읽기
 *     (`stored_cut_slope` · `berm_from` · `stored_shoulder_extend` · `stored_tilt` · `curve_widening_args`) ·
 *     계획고 = `design_elevation_from_longitudinal`. 거울 시험 `test_511_b4_cross_save_mirror.py`.
 *   crossOptions = 파이썬 `compute_cross_design` 키 → TS 짝 키(Node `cross.design` 도 이것).
 * 순수 — 화면 · fetch · 세션 없음.
 * ========================================================================== */

import { bermSpansFromStructures, bermSpecAt } from "@util/common_util_berm_spans";
import {
  BERM_DEFAULT_DEPTH_M,
  BERM_DEFAULT_INTERVAL_M,
  BERM_DEFAULT_SLOPE_DEG,
  BERM_DEFAULT_WIDTH_M,
  type BermSpec,
} from "@util/common_util_cross_berm";
import { computeCrossDesign } from "@util/common_util_cross_design";
import type { CrossDesignOptions, CrossGroundSample } from "@util/common_util_cross_design";
import type { CulvertPipePoint } from "@util/common_util_culvert_sets";
import type { DtmGrid } from "@util/common_util_surface_sampler";
import {
  extendUnclosed,
  type CrossGroundPoint,
  type ExtendInfo,
  type UnclosedDesign,
} from "../../B05_Profile/logic/B05_Profile_Sections_Ground";
import { USER_TOUCHED_KEYS } from "./B06_Section_Design_Keys";
import { facilityAt, facilityRanges, type FacilityStructure } from "./B06_Section_Cross_Enforce";

type Raw = Record<string, unknown>;

/** 파이썬 `compute_cross_design` 키 → TS 짝 키(거울 시험 test_b06_cross_design_mirror 표와 같음). */
const CROSS_OPTION_KEYS: Record<string, keyof CrossDesignOptions> = {
  ground_type: "groundType",
  section_mode: "sectionMode",
  ditch_side: "ditchSide",
  ditch_type: "ditchType",
  paved: "paved",
  rock_boundary_offset_m: "rockBoundaryOffsetM",
  two_stage_slope: "twoStageSlope",
  cut_slope_ratio: "cutSlopeRatio",
  ditch_enabled: "ditchEnabled",
  ditch_choice: "ditchChoice",
  surface_drop_m: "surfaceDropM",
  plan_radius_m: "planRadiusM",
  curve_outer_side: "curveOuterSide",
  curve_widening_m: "curveWideningM",
  shoulder_extend_left_m: "shoulderExtendLeftM",
  shoulder_extend_right_m: "shoulderExtendRightM",
  tilted: "tilted",
  tilt_pct: "tiltPct",
};

/** 파이썬 BermSpec(NamedTuple → dict) → TS BermSpec. */
function bermOf(value: unknown): BermSpec | null {
  if (!value || typeof value !== "object") return null;
  const berm = value as Record<string, number | null>;
  return {
    widthM: berm.width_m as number,
    intervalM: berm.interval_m as number,
    slopeDeg: berm.slope_deg as number,
    depthM: berm.depth_m as number,
    depthLeftM: berm.depth_left_m ?? null,
    depthRightM: berm.depth_right_m ?? null,
  };
}

/** 파이썬 키 입력 → 엔진 입력(모르는 키 = 던짐). */
export function crossOptions(
  raw: Raw,
  standard: CrossDesignOptions["standard"],
): CrossDesignOptions {
  const options: Raw = { standard };
  for (const [key, value] of Object.entries(raw)) {
    if (key === "berm") options.berm = bermOf(value);
    else if (key in CROSS_OPTION_KEYS) options[CROSS_OPTION_KEYS[key]] = value;
    else throw new Error(`모르는 횡단 설계 키: ${key}`);
  }
  return options as unknown as CrossDesignOptions;
}

const isNum = (value: unknown): value is number =>
  typeof value === "number" && Number.isFinite(value);

/** 파이썬 `stored_cut_slope` — 측점별 암 절토 경사 · 없거나 0 = null. */
const storedCutSlope = (design: Raw): number | null =>
  isNum(design.cut_slope_ratio_user) && design.cut_slope_ratio_user > 0
    ? design.cut_slope_ratio_user
    : null;

/** 파이썬 `berm_from` — 소단 제원 dict + 쪽마다 옮긴 깊이 → BermSpec(python 키). */
function bermFrom(spec: unknown, sides: Raw): Raw | null {
  if (!spec || typeof spec !== "object" || Array.isArray(spec)) return null;
  const own = (side: string): number | null => {
    const value = sides[`berm_depth_${side}_m`];
    return isNum(value) ? Math.max(value, 0) : null;
  };
  const s = spec as Raw;
  const field = (key: string, fallback: number): number => Number(s[key] ?? fallback);
  const out = {
    width_m: field("width_m", BERM_DEFAULT_WIDTH_M),
    interval_m: field("interval_m", BERM_DEFAULT_INTERVAL_M),
    slope_deg: field("slope_deg", BERM_DEFAULT_SLOPE_DEG),
    depth_m: Math.max(field("depth_m", BERM_DEFAULT_DEPTH_M), 0),
  };
  if (!Object.values(out).every(Number.isFinite)) return null; // 파이썬 TypeError · ValueError
  return { ...out, depth_left_m: own("left"), depth_right_m: own("right") };
}

const storedBerm = (design: Raw): Raw | null => bermFrom(design.berm, design);

/** 파이썬 `stored_shoulder_extend` — 없거나 음수 = 0. */
const storedShoulder = (design: Raw): Raw =>
  Object.fromEntries(
    (["left", "right"] as const).map((side) => {
      const value = design[`shoulder_extend_${side}_m`];
      return [`shoulder_extend_${side}_m`, isNum(value) ? Math.max(value, 0) : 0];
    }),
  );

/** 파이썬 `stored_tilt`. */
const storedTilt = (design: Raw): { tilted: boolean; tilt_pct: number | null } => ({
  tilted: Boolean(design.tilted),
  tilt_pct: isNum(design.tilt_pct) ? design.tilt_pct : null,
});

/** 파이썬 `curve_widening_args`. */
const curveArgs = (section: Raw): Raw => ({
  plan_radius_m: section.plan_radius_m ?? null,
  curve_outer_side: section.curve_outer_side ?? null,
  curve_widening_m: section.curve_widening_m ?? null,
});

/** 파이썬 `design_elevation_from_longitudinal` — 계획선 표본 선형 보간 · 범위 밖 끝값 · 없으면 null. */
export function elevationAt(
  samples: ReadonlyArray<{ chainage_m?: unknown; elevation_m?: unknown }>,
  chainageM: number,
): number | null {
  const rows = samples.filter((s) => isNum(s.elevation_m) && isNum(s.chainage_m)) as Array<{
    chainage_m: number;
    elevation_m: number;
  }>;
  if (!rows.length) return null;
  if (chainageM <= rows[0].chainage_m) return rows[0].elevation_m;
  const last = rows[rows.length - 1];
  if (chainageM >= last.chainage_m) return last.elevation_m;
  for (let index = 1; index < rows.length; index += 1) {
    const [previous, current] = [rows[index - 1], rows[index]];
    if (chainageM > current.chainage_m) continue;
    const span = current.chainage_m - previous.chainage_m;
    if (span <= 0) return current.elevation_m;
    const ratio = (chainageM - previous.chainage_m) / span;
    return previous.elevation_m + (current.elevation_m - previous.elevation_m) * ratio;
  }
  return last.elevation_m;
}

/** 저장분 공통 입력(파이썬 넷이 같은 꼴로 모음) — 포장 · 하강 · 기울임은 부르는 자리가 덮음. */
function storedOptions(design: Raw, section: Raw, rockDefaultM: number): Raw {
  return {
    ground_type: String(design.ground_type || "ripping_rock"),
    section_mode: String(design.section_mode || "left_cut"),
    ditch_side: design.ditch_side ?? null,
    ditch_type: String(design.ditch_type || "standard"),
    paved: Boolean(design.paved),
    rock_boundary_offset_m:
      "rock_boundary_offset_m" in design ? design.rock_boundary_offset_m : rockDefaultM,
    two_stage_slope: Boolean(design.two_stage_slope),
    cut_slope_ratio: storedCutSlope(design),
    ditch_enabled: design.ditch_enabled ?? null,
    ditch_choice: design.ditch_choice ?? null,
    berm: storedBerm(design),
    ...curveArgs(section),
    ...storedShoulder(design),
  };
}

/** 측점 하나(서버 상세 꼴) — 쓰는 칸만. */
export interface SaveSection {
  chainage_m: number;
  design?: Raw | null;
  samples?: CrossGroundSample[];
  frame?: { origin?: { x: number; y: number }; left_xy?: [number, number] };
  plan_radius_m?: number | null;
  curve_outer_side?: string | null;
  curve_widening_m?: number | null;
}

export interface SaveCrossInput {
  /** 종단 계획선 표본(`design_profiles[0].samples`). */
  profile: ReadonlyArray<{ chainage_m?: unknown; elevation_m?: unknown }>;
  sections: SaveSection[];
  standard: CrossDesignOptions["standard"];
  rockDefaultM: number;
  pipes: readonly CulvertPipePoint[];
  /** 구조물 정본 — null = 못 읽음(소단 = 저장분 그대로 · 포장 · 맹암거 구간 없음). */
  structures: readonly FacilityStructure[] | null;
}

/** 측점마다 결과 — 설계 없는 측점 null · 넓혔으면 표본 · 넓힘 기록. */
export interface SaveCrossRow {
  design: Raw;
  samples?: CrossGroundSample[];
  extended?: ExtendInfo;
}

/** [저장] 횡단 한 바퀴 — 파이썬 `_recompute` 의 설계선 · 넓힘 · 포장 · 하강 넷(차례 그대로 · 제자리 아님). */
export function enforceSavedCross(
  input: SaveCrossInput,
  grid: () => DtmGrid | null,
): Array<SaveCrossRow | null> {
  const ranges = facilityRanges(input.pipes, input.structures ?? []);
  const spans = input.structures
    ? bermSpansFromStructures(input.structures as Parameters<typeof bermSpansFromStructures>[0])
    : null;
  const rows = input.sections.map((section): SaveCrossRow | null =>
    section.design && typeof section.design === "object" ? { design: section.design } : null,
  );
  const elevation = (section: SaveSection) => elevationAt(input.profile, section.chainage_m);
  const compute = (samples: CrossGroundSample[] | undefined, z: number | null, raw: Raw) => {
    try {
      return computeCrossDesign(
        samples ?? [],
        z,
        crossOptions(raw, input.standard),
      ) as unknown as Raw;
    } catch {
      return null; // 파이썬 ValueError · Node { error } 자리 — 저장분 그대로
    }
  };
  /** 다시 세운 설계에 사용자 값 · 상태 승계(파이썬 `apply_designs`). */
  const keep = (next: Raw, from: Raw): Raw => {
    for (const key of ["status", "pavement_suggested", ...USER_TOUCHED_KEYS])
      if (from[key] !== undefined && from[key] !== null) next[key] = from[key];
    return next;
  };
  const at = (section: SaveSection) => facilityAt(ranges, section.chainage_m);
  const sectionRaw = (section: SaveSection) => section as unknown as Raw;

  // ① 모든 측점 설계선(`enforce_design_lines`) — 소단 = 구조물 정본 구간 · 하강 · 기울임 = 지금 시설
  input.sections.forEach((section, index) => {
    const row = rows[index];
    if (!row) return;
    const design = spans
      ? { ...row.design, berm: bermSpecAt(spans, section.chainage_m) }
      : row.design;
    const facility = at(section);
    const next = compute(section.samples, elevation(section), {
      ...storedOptions(design, sectionRaw(section), input.rockDefaultM),
      surface_drop_m: facility.surfaceDropM,
      tilted: facility.tilted,
      tilt_pct: facility.tiltPct,
    });
    if (next) row.design = keep(next, design);
  });
  // ② 미교차 넓힘(`extend_unclosed_sections`) — 열린 쪽만 +5 m · DTM 격자 · 넓힌 표본으로 다시 셈
  const open = rows.some((row) => row?.design.slope_unclosed);
  const map = open ? grid() : null;
  input.sections.forEach((section, index) => {
    const row = rows[index];
    const origin = section.frame?.origin;
    const left = section.frame?.left_xy;
    if (!map || !row?.design.slope_unclosed || !origin || !left) return;
    const design = row.design;
    const z = elevation(section);
    const raw = {
      ...storedOptions(design, sectionRaw(section), input.rockDefaultM),
      surface_drop_m: at(section).surfaceDropM,
      ...storedTilt(design),
    };
    let wide;
    try {
      wide = extendUnclosed(
        (section.samples ?? []) as Array<Partial<CrossGroundPoint>>,
        [origin.x, origin.y],
        left,
        (samples) => {
          const next = compute(samples as CrossGroundSample[], z, raw);
          if (!next) throw new Error("넓힘 셈 못 함");
          return next as unknown as UnclosedDesign;
        },
        map,
      );
    } catch {
      return; // 파이썬 ValueError · KeyError — 그 측점 그대로
    }
    if (!wide || (!wide.info.left_m && !wide.info.right_m)) return;
    const samples = wide.samples as CrossGroundSample[];
    const next = compute(samples, z, raw);
    if (!next) return;
    rows[index] = { design: keep(next, design), samples, extended: wide.info };
  });
  const samplesOf = (index: number) => rows[index]?.samples ?? input.sections[index].samples;
  // ③ 포장 구간(`enforce_pavement_ranges`) — 포장 · 기울임이 저장분과 다른 측점만
  input.sections.forEach((section, index) => {
    const row = rows[index];
    if (!row) return;
    const design = row.design;
    const facility = at(section);
    const tilt = storedTilt(design);
    if (
      Boolean(design.paved) === facility.paved &&
      tilt.tilted === facility.tilted &&
      tilt.tilt_pct === facility.tiltPct
    )
      return;
    const next = compute(samplesOf(index), elevation(section), {
      ...storedOptions(design, sectionRaw(section), input.rockDefaultM),
      paved: facility.paved,
      surface_drop_m: facility.surfaceDropM,
      tilted: facility.tilted,
      tilt_pct: facility.tiltPct,
    });
    if (next) row.design = keep(next, design);
  });
  // ④ 세월교 노면 하강(`enforce_ford_surface_drops`) — 하강이 저장분과 다른 측점만
  input.sections.forEach((section, index) => {
    const row = rows[index];
    if (!row) return;
    const design = row.design;
    const wanted = at(section).surfaceDropM;
    if (Math.abs(wanted - Number(design.surface_drop_m || 0)) < 1e-6) return;
    const next = compute(samplesOf(index), elevation(section), {
      ...storedOptions(design, sectionRaw(section), input.rockDefaultM),
      surface_drop_m: wanted,
      ...storedTilt(design),
    });
    if (next) row.design = keep(next, design);
  });
  return rows;
}