/* =============================================================================
 * spreadsheet_commands_sheet.ts  (주인 A)
 * 시트 명령 — 더하기 · 지우기 · 이름 · 옮기기 · 통째 바꿔 넣기. 들머리는 `applyCommand`(commands).
 * ========================================================================== */

import { clone, CommandError, restoreChanged, rewriteAll, sheetOf } from "./spreadsheet_commands";
import type { Of } from "./spreadsheet_commands";
import type { Command, CommandEffect, Workbook } from "./spreadsheet_types";

function checkSheetName(book: Workbook, name: string, self?: string) {
  if (!name.trim() || name.length > 31) throw new CommandError("시트 이름은 1~31 글자");
  if (/[[\]:*?/\\]/.test(name) || name.startsWith("'") || name.endsWith("'"))
    throw new CommandError("시트 이름에 못 쓰는 글자: [ ] : * ? / \\ 와 앞뒤 '");
  if (book.시트.some((s) => s.id !== self && s.이름.toLowerCase() === name.toLowerCase()))
    throw new CommandError(`같은 이름 시트가 있음: ${name}`);
}

export function addSheet(book: Workbook, cmd: Of<"시트더하기">): CommandEffect {
  if (book.시트.some((s) => s.id === cmd.시트.id))
    throw new CommandError(`같은 id 시트가 있음: ${cmd.시트.id}`);
  checkSheetName(book, cmd.시트.이름);
  book.시트.splice(Math.max(0, Math.min(cmd.자리, book.시트.length)), 0, clone(cmd.시트));
  return { undo: { 종류: "시트지우기", 시트: cmd.시트.id }, cells: [], rebuild: true };
}

export function removeSheet(book: Workbook, cmd: Of<"시트지우기">): CommandEffect {
  const s = sheetOf(book, cmd.시트);
  if (book.시트.length === 1) throw new CommandError("마지막 시트는 못 지움");
  const at = book.시트.indexOf(s);
  const old = book.시트.map(clone);
  rewriteAll(book, cmd);
  book.시트.splice(at, 1);
  if (book.활성 === s.id) book.활성 = book.시트[Math.min(at, book.시트.length - 1)].id;
  const undo: Command[] = [
    { 종류: "시트더하기", 시트: old[at], 자리: at },
    ...restoreChanged(book, old),
  ];
  return { undo: { 종류: "묶음", 명령: undo }, cells: [], rebuild: true };
}

export function renameSheet(book: Workbook, cmd: Of<"시트이름">): CommandEffect {
  const s = sheetOf(book, cmd.시트);
  checkSheetName(book, cmd.이름, s.id);
  const prev = s.이름;
  rewriteAll(book, cmd);
  s.이름 = cmd.이름;
  return { undo: { 종류: "시트이름", 시트: s.id, 이름: prev }, cells: [], rebuild: true };
}

export function moveSheet(book: Workbook, cmd: Of<"시트옮기기">): CommandEffect {
  const s = sheetOf(book, cmd.시트);
  const from = book.시트.indexOf(s);
  book.시트.splice(from, 1);
  book.시트.splice(Math.max(0, Math.min(cmd.자리, book.시트.length)), 0, s);
  return { undo: { 종류: "시트옮기기", 시트: s.id, 자리: from }, cells: [], rebuild: false };
}

export function replaceSheet(book: Workbook, cmd: Of<"시트통째">): CommandEffect {
  const at = book.시트.findIndex((x) => x.id === cmd.시트.id);
  if (at < 0) throw new CommandError(`없는 시트: ${cmd.시트.id}`);
  const prev = book.시트[at];
  book.시트[at] = clone(cmd.시트);
  const undo: Of<"시트통째"> = { 종류: "시트통째", 시트: prev };
  if (cmd.서식) {
    undo.서식 = book.서식;
    book.서식 = clone(cmd.서식);
  }
  return { undo, cells: [], rebuild: true };
}