/**
 * 솔플레이트 (결정 2026-11-06, RAG/받침방위각_솔플레이트검토.md §3, spec.md §5.3, 시안 Version 110–113). Pure.
 * Replaces the 2026-11-03 C안 (받침높이 H 고정, h3 = H − T, S 입력) by the user's decision to follow the 시안:
 *
 * - 평면: L = A + 여유 (거더 방향 = 방위각), W = B + 여유 (여유 100). A × B per bearing; absent = 700 × 640 (P1 전열 값, 가정).
 * - S: 같은 거더 양끝 받침의 z 차 / 수평거리 (girderPairs). 없으면 교각 종단경사 입력 → 같은 구조물 다른 열의 같은 순번 값
 *   ("가정", WS03) → 0 % (WS03). 받침별 직접 수정 = "수정됨".
 * - T: 열마다 max(T_min, ⌈max(T_min + L·|S|/2)⌉). 직접 고치면 "수정됨", T2 < T_min이면 WS02.
 *   T1 = round(T + L·|S|/2) 오르막 쪽, T2 = round(T − L·|S|/2).
 * - 높이: 거더 하면 고정 — 블럭 상면 = z − (T − T_ref); 받침 본체 h3 고정 (181, P1 상세도).
 */
import { type BearingPair, pairOf } from './bearing-pair';

export interface SoleSettings {
  /** 받침 본체 높이 h3 (mm). */
  h3Mm?: number;
  /** T_ref: the solplate thickness the workbook z assumed (mm). */
  tRefMm?: number;
  /** T_min: the thin-end minimum (mm). */
  tMinMm?: number;
  /** 솔플 여유 L − A = W − B (mm). */
  marginMm?: number;
  /** 받침 평면 A (거더 방향) × B per bearing number (mm). */
  plates?: Record<string, { aMm: number; bMm: number }>;
  /** T per row, when typed (mm). Absent = 자동. */
  tByRow?: Partial<Record<string, number>>;
  /** S per bearing number, when typed (%). */
  slopePct?: Record<string, number>;
}

export const SOLE_DEFAULTS = { h3Mm: 181, tRefMm: 30, tMinMm: 22, marginMm: 100, aMm: 700, bMm: 640 } as const;

export type SlopeSource = '계산' | '입력' | '가정' | '수정됨' | '없음';

export interface BearingSole {
  no: number;
  row: string;
  pair?: { structure: string; no: number };
  /** 방위각 검사 (″): this bearing's input azimuth against the direction to its pair (Q-SH4, WS01 > 10″). Absent without a pair. */
  azimuthCheckSec?: number;
  slopePct: number;
  slopeSource: SlopeSource;
  aMm: number;
  bMm: number;
  /** L along the girder, W across it (mm). */
  L: number;
  W: number;
  /** Row thickness T and whether it was typed; T1 on the 오르막 쪽, T2 on the other end (mm). */
  T: number;
  tTyped: boolean;
  T1: number;
  T2: number;
  /** This bearing's requirement T_min + L·|S|/2 (mm). */
  tReq: number;
  h3: number;
  /** Block top drop T − T_ref (mm, + = the block gets lower). */
  dropMm: number;
  /** Unit vector (E, N) towards the 오르막 쪽, or null when S = 0. */
  uphill: { e: number; n: number } | null;
  warnings: ('WS01' | 'WS02' | 'WS03' | 'WS04')[];
}

export interface SoleBearing {
  no: number;
  row: string;
  azimuthDeg: number;
}

const DEG = Math.PI / 180;

/**
 * Solplates of one structure. `pairs` are the girder pairs of the whole bridge (girderPairs over A1, P1 … Pn, A2);
 * `fallbackSlopePct` is the structure's 종단경사 input (%), when given.
 */
export function structureSoles(structure: string, bearings: SoleBearing[], settings: SoleSettings = {}, pairs: BearingPair[] = [], fallbackSlopePct?: number): BearingSole[] {
  const s = { ...SOLE_DEFAULTS, ...settings };
  const rows = [...new Set(bearings.map((b) => b.row))];
  const order = (b: SoleBearing) => bearings.filter((q) => q.row === b.row).indexOf(b);
  const paired = new Map(bearings.map((b) => [b.no, pairOf(pairs, structure, b.no)]));
  const pairSlope = (b: SoleBearing) => paired.get(b.no)?.slopePct;

  const slopes = bearings.map((b) => {
    const typed = settings.slopePct?.[String(b.no)];
    if (typed !== undefined) return { slopePct: typed, source: '수정됨' as SlopeSource };
    const own = pairSlope(b);
    if (own !== undefined) return { slopePct: own, source: '계산' as SlopeSource };
    if (fallbackSlopePct !== undefined) return { slopePct: fallbackSlopePct, source: '입력' as SlopeSource };
    // The same position in another row that has a pair (시안: 후열 ⑥ ← 전열 ①).
    for (const other of rows.filter((r) => r !== b.row)) {
      const twin = bearings.filter((q) => q.row === other)[order(b)];
      const v = twin && pairSlope(twin);
      if (v !== undefined) return { slopePct: v, source: '가정' as SlopeSource };
    }
    return { slopePct: 0, source: '없음' as SlopeSource };
  });

  const plate = (b: SoleBearing) => s.plates?.[String(b.no)] ?? { aMm: s.aMm, bMm: s.bMm };
  const req = bearings.map((b, i) => s.tMinMm + ((plate(b).aMm + s.marginMm) * Math.abs(slopes[i].slopePct)) / 200);
  const rowT = new Map(rows.map((r) => {
    const typed = settings.tByRow?.[r];
    const auto = Math.max(s.tMinMm, Math.ceil(Math.max(...bearings.map((b, i) => (b.row === r ? req[i] : -Infinity))) - 1e-9));
    return [r, { T: typed ?? auto, typed: typed !== undefined }];
  }));

  return bearings.map((b, i) => {
    const { aMm, bMm } = plate(b);
    const L = aMm + s.marginMm, W = bMm + s.marginMm;
    const { slopePct, source } = slopes[i];
    const { T, typed } = rowT.get(b.row)!;
    const half = (L * Math.abs(slopePct)) / 200;
    const T1 = Math.round(T + half), T2 = Math.round(T - half);
    const pair = paired.get(b.no);
    const warnings: BearingSole['warnings'] = [...(pair?.warnings ?? [])];
    if (T2 < s.tMinMm) warnings.push('WS02');
    if (source === '가정' || source === '없음') warnings.push('WS03');
    // S runs along the structure order, which is the azimuth direction (girderPairs looks ahead along it).
    const dir = { e: Math.sin(b.azimuthDeg * DEG), n: Math.cos(b.azimuthDeg * DEG) };
    const sign = Math.sign(slopePct);
    return {
      no: b.no, row: b.row, pair: pair ? (pair.from.structure === structure ? pair.to : pair.from) : undefined,
      azimuthCheckSec: pair ? (pair.from.structure === structure && pair.from.no === b.no ? pair.fromCheckSec : pair.toCheckSec) : undefined,
      slopePct, slopeSource: source, aMm, bMm, L, W, T, tTyped: typed, T1, T2, tReq: req[i], h3: s.h3Mm,
      dropMm: T - s.tRefMm, uphill: sign ? { e: sign * dir.e, n: sign * dir.n } : null, warnings,
    };
  });
}

/** Input problems of the settings, in Korean; empty when they can build solplates. */
export function soleSettingsIssues(settings: SoleSettings | undefined): string[] {
  if (!settings) return [];
  const out: string[] = [];
  const positive = (v: unknown, label: string) => {
    if (v !== undefined && !(typeof v === 'number' && Number.isFinite(v) && v > 0)) out.push(`${label}은(는) 0보다 커야 합니다.`);
  };
  positive(settings.h3Mm, '받침 높이 h3');
  positive(settings.tRefMm, 'T_ref');
  positive(settings.tMinMm, 'T_min');
  if (settings.marginMm !== undefined && !(Number.isFinite(settings.marginMm) && settings.marginMm >= 0)) out.push('솔플 여유는 0 이상이어야 합니다.');
  for (const [no, p] of Object.entries(settings.plates ?? {})) { positive(p.aMm, `받침 ${no} A`); positive(p.bMm, `받침 ${no} B`); }
  for (const [row, t] of Object.entries(settings.tByRow ?? {})) positive(t, `${row} T`);
  for (const [no, v] of Object.entries(settings.slopePct ?? {})) if (!Number.isFinite(v)) out.push(`받침 ${no} S는 숫자여야 합니다.`);
  return out;
}