/* =============================================================================
 * common_util_formula_doc_table.ts
 * 수식 문서 표 찾기(PLAN 802-1) — 조건에 맞는 한 줄(범위 규칙) · 칸 값 · 분수 글 칸
 *   파이썬 짝 = resources/master_data/scripts/master_doc_link.py(find · _cell · _arith)
 *   · 거울 시험 test_802_1_formula_doc.py · 화면 · DOM · fetch 없음
 * ========================================================================== */

import { DocError, parse, walk, type Node } from "./common_util_formula_doc";
import { Broken, Gap, binary, isNum, plainText, same } from "./common_util_formula_doc_calc";

type Payload = Record<string, unknown>;

export interface DocTable {
  키?: string;
  원문번호?: string;
  조건?: Record<string, string>;
  범위규칙?: string;
  값칸?: Record<string, unknown>;
  줄: Record<string, unknown>[];
}

function matchRow(table: DocTable, row: Record<string, unknown>, cond: string, want: unknown) {
  if (!(cond in row)) return true;
  const have = row[cond];
  if (table.조건?.[cond] !== "범위") return same(have, want);
  const [low, high] = have as [number | null, number | null];
  if (!isNum(want) && (low !== null || high !== null))
    throw new Broken(`표 ${table.키} 범위 조건에 수 아닌 값`);
  const w = want as number;
  const [first, ...more] = String(table.범위규칙 || "초과·이하").split(" · ");
  const rule = first.split(" (")[0];
  const ge = low === null || w >= low;
  const gt = low === null || w > low;
  const le = high === null || w <= high;
  if (rule === "이상·이하") return ge && le;
  if (rule === "초과·이하" || rule === "이하") return gt && le;
  if (rule === "이상·미만") {
    const tops = table.줄
      .map((r) => r[cond] as [number | null, number | null] | undefined)
      .filter((x) => x && x[1] !== null)
      .map((x) => x![1] as number);
    const closed = more.some((x) => x.includes("이하 포함")) && high === Math.max(...tops);
    return ge && (high === null || w < high || (closed && w === high));
  }
  throw new Broken(`모르는 범위규칙 「${table.범위규칙}」`);
}

/** 조건에 맞는 한 줄 — 「이하」 · 「이상·이하」 는 위 끝이 가장 작은 줄 · 여럿이면 찾는 칸 있는 줄 */
export function findRow(
  table: DocTable,
  conds: Record<string, unknown>,
  want?: string,
): Record<string, unknown> {
  for (const c of Object.keys(conds))
    if (!(c in (table.조건 ?? {}))) throw new Broken(`표 ${table.키} 에 없는 조건 「${c}」`);
  let hits = table.줄.filter((r) =>
    Object.entries(conds).every(([c, v]) => matchRow(table, r, c, v)),
  );
  const rule = String(table.범위규칙 ?? "").split(" · ")[0];
  if (hits.length > 1 && (rule === "이하" || rule === "이상·이하"))
    for (const c of Object.keys(conds)) {
      const ups = hits
        .filter((r) => table.조건?.[c] === "범위" && r[c])
        .map((r) => (r[c] as [number | null, number | null])[1]);
      if (ups.length && !ups.includes(null)) {
        const least = Math.min(...(ups as number[]));
        hits = hits.filter((r) => !r[c] || (r[c] as [unknown, number])[1] === least);
      }
    }
  if (hits.length > 1 && want) hits = hits.filter((r) => want in r);
  if (hits.length !== 1) {
    const what = Object.entries(conds)
      .map(([c, v]) => `${c} ${plainText(v)}`)
      .join(" · ");
    const where = `표 ${table.키}(${table.원문번호})`;
    throw new Gap(`${where}에 ${what} 인 줄이 ${hits.length ? `${hits.length}개` : "없음"}`);
  }
  return hits[0];
}

/** 표 칸의 분수 · 식 글(「1/1.30」) → 수 · 아니면 글 그대로 */
export function cellArith(text: string): number | string {
  let node: Node;
  try {
    node = parse(text);
  } catch (e) {
    if (e instanceof DocError) return text;
    throw e;
  }
  for (const n of walk(node)) if (!["num", "bin", "neg"].includes(n[0])) return text;
  const ev = (n: Node): number => {
    if (n[0] === "num") return n[1];
    if (n[0] === "neg") return -ev(n[1]);
    if (n[0] === "bin") return binary(n[1], ev(n[2]), ev(n[3])) as number;
    return NaN;
  };
  const got = ev(node);
  return Number.isFinite(got) ? got : text;
}

/** 표 연결 값 — 줄 찾기 · 칸 · 빈 칸 = Gap · 범위 = Broken */
export function tableValue(table: DocTable, p: Payload): unknown {
  const col = String(p.칸);
  const row = findRow(table, (p.조건 ?? {}) as Record<string, unknown>, col);
  if (!(col in row)) {
    if (!(col in (table.값칸 ?? {})) && !table.줄.some((r) => col in r))
      throw new Broken(`표 ${table.키} 에 칸 「${col}」 없음`);
    throw new Gap(`표 ${table.키} 고른 줄에 「${col}」 값 없음`);
  }
  const v = row[col];
  if (v === null || v === undefined) throw new Gap(`칸 「${col}」 값 없음 — 관리자가 채울 값`);
  if (Array.isArray(v)) throw new Broken(`칸 「${col}」 값이 범위 — 입력으로 받아야 함`);
  return typeof v === "string" ? cellArith(v) : v;
}