/**
 * 교량받침 표 (2026-11-03, 모델값). Pure: the ELEVATION TABLE and the 솔플레이트 TABLE of a pier, every value from the
 * model. No drawing values are used (C안). Lengths in mm; EL.X in m.
 *
 * - EL.X: the mortar top = the Excel z (padTop, Q16).
 * - h1: block height (block top − block bottom). h2: mortar (pad top − block top). h3: bearing body (solplate rule).
 * - h4: solplate centre thickness T. E = h1 + h2 + h3 + h4.
 * - C1: bearing centre to the outer block edge along 교축. C2: between the two bearings of a pair, along 교축 (on the
 *   front row). C3: block span of the pair along 교축 (front row). C4·C5: 교각축 margins (bearing-layout). C6: block depth
 *   along 교각축.
 * - S1·S2: block rebar bars from the model (bearing-block): count and bar length. For 일체 the pair's bars sit on the front row.
 */
import type { PierModel } from './geometry';
import { bearingEdgeDistances, pairEccentricities } from './bearing-layout';
import { INTEGRATED_BLOCK } from './integrated-block';
import { bearingBlockRebar, type BarRow } from './rebar/bearing-block';

/** Depth of a 분리 bearing block along 교각축 (mm), the same value as the block rebar. */
export const BLOCK_DEPTH_MM = 1200;

export interface ElevationRow {
  no: number;
  row: '전열' | '후열';
  elx: number;
  /** 교좌면 EL (m): the block bottom. */
  seatEl: number;
  h1: number;
  h2: number;
  h3: number;
  h4: number;
  E: number;
  C1: number;
  /** Front row only; null on the back row. */
  C2: number | null;
  C3: number | null;
  C4: number;
  C5: number;
  C6: number;
  S1: BarSummary | null;
  S2: BarSummary | null;
}

export interface BarSummary {
  count: number;
  length: number;
}

export interface SolplateRow {
  no: number;
  /** 기울기 S (%), negative as drawn. */
  S: number;
  L: number;
  W: number;
  T: number;
  T1: number;
  T2: number;
  /** Check: T1 − T2 against L·|S|/100 (mm). */
  checkLhs: number;
  checkRhs: number;
  ok: boolean;
}

function barSummary(bars: BarRow[], name: 'S1' | 'S2'): BarSummary | null {
  const hit = bars.filter((x) => x.name === name);
  if (hit.length === 0) return null;
  return { count: hit.reduce((sum, x) => sum + x.count, 0), length: hit[0].length };
}

export function elevationRows(m: PierModel): ElevationRow[] {
  const edges = bearingEdgeDistances(m);
  const rebar = bearingBlockRebar(m);
  const pairs = pairEccentricities(m.blocks);
  return [...m.blocks]
    .sort((a, b) => a.no - b.no)
    .map((b) => {
      const plan = b.plan;
      const h1 = Math.round((b.top - b.bottom) * 1000);
      const h2 = Math.round((b.padTop - b.top) * 1000);
      const edge = edges.find((e) => e.no === b.no)!;
      const ib = m.integratedBlocks.find((x) => (b.row === '전열' ? x.frontNo : x.backNo) === b.no);
      // C1: bearing centre to the outer edge of its block along 교축 (1200 block centred on the bearing, or the 2500 block).
      const C1 = ib ? Math.round(Math.abs(b.n - (b.n <= ib.n ? ib.n - INTEGRATED_BLOCK.length / 2000 : ib.n + INTEGRATED_BLOCK.length / 2000)) * 1000) : 600;
      const pair = pairs.find((p) => (b.row === '전열' ? p.frontNo : p.backNo) === b.no);
      const front = b.row === '전열';
      const C2 = front && pair ? Math.round(Math.abs(m.blocks.find((x) => x.no === pair.backNo && x.row === '후열')!.n - b.n) * 1000) : null;
      const C3 = front && pair ? (ib ? INTEGRATED_BLOCK.length : (C2 ?? 0) + BLOCK_DEPTH_MM) : null;
      const bars = rebar.find((r) => r.no === b.no && r.row === b.row)?.bars ?? [];
      return {
        no: b.no,
        row: b.row,
        elx: b.padTop,
        seatEl: b.bottom,
        h1,
        h2,
        h3: plan.h3,
        h4: plan.T,
        E: h1 + h2 + plan.h3 + plan.T,
        C1,
        C2,
        C3,
        C4: Math.round(edge.leftMm),
        C5: Math.round(edge.rightMm),
        C6: BLOCK_DEPTH_MM,
        S1: barSummary(bars, 'S1'),
        S2: barSummary(bars, 'S2'),
      };
    });
}

export function solplateRows(m: PierModel): SolplateRow[] {
  return [...m.blocks]
    .sort((a, b) => a.no - b.no)
    .map((b) => {
      const p = b.plan;
      const checkLhs = p.T1 - p.T2;
      const checkRhs = (p.L * Math.abs(p.slopePct)) / 100;
      return {
        no: b.no,
        S: p.slopePct,
        L: p.L,
        W: p.W,
        T: p.T,
        T1: p.T1,
        T2: p.T2,
        checkLhs,
        checkRhs,
        ok: Math.abs(checkLhs - checkRhs) < 1e-6,
      };
    });
}

/**
 * S1·S2 of one pair along 교축 (mm, 2026-11-03): S1 = bearing centre to the coping edge on each outer side, S2 = between
 * the two bearing centres. The coping is centred on the axis with width B (model copingB), so S1 + S2 + S1 = B.
 */
export interface PairCopingSpans {
  S1Low: number;
  S2: number;
  S1High: number;
  copingWidth: number;
}

export function pairCopingSpans(m: PierModel, pairIndex: number): PairCopingSpans | null {
  const pair = pairEccentricities(m.blocks)[pairIndex];
  if (!pair) return null;
  const f = m.blocks.find((b) => b.no === pair.frontNo && b.row === '전열')!;
  const k = m.blocks.find((b) => b.no === pair.backNo && b.row === '후열')!;
  const lo = Math.min(f.n, k.n);
  const hi = Math.max(f.n, k.n);
  const half = m.copingB / 2;
  return {
    S1Low: Math.round((lo + half) * 1000),
    S2: Math.round((hi - lo) * 1000),
    S1High: Math.round((half - hi) * 1000),
    copingWidth: Math.round(m.copingB * 1000),
  };
}