/* =============================================================================
 * spreadsheet_condition.ts
 * 엑셀 「조건 만들기」 — 칸 우클릭 → 줄 판: 만약 [칸·알약] [비교] [값] → [칸·알약·값] · 아니면 만약 … · 아니면 → 고른 칸에 IF 식(중첩 IF)
 * 엑셀로 쓴 IF 도 같은 줄로 다시 엶(`formulaToDraft`) · 못 바꾸는 식은 「식 그대로 고침」 안내
 * 부르는 쪽이 `conditions` 선택을 줄 때만 붙음(`attachCondition` · 늦게 불러옴) → 그 밖 화면은 그대로
 * 앞 절반(DraftToFormula · formulaToDraft)은 DOM 을 모름 — 시험이 이 구역만 떼어 Node 로 돌림
 * 글 [한, 영] 짝은 아래 TEXT
 * ========================================================================== */

import { currentLanguageIndex } from "@ui/ui_template_locale";
import { createButton, el } from "@ui/ui_template_elements";
import { openModal } from "@ui/ui_template_modal";
import type { PartHandle, SpreadsheetContext } from "./spreadsheet_view_types";
import { toA1 } from "./spreadsheet_address";
import {
  COND_OPS,
  CELL,
  draftToFormula,
  formulaToDraft,
  type CondBranch,
  type CondDraft,
  type CondOp,
  type CondOperand,
} from "./spreadsheet_condition_text";
import "./spreadsheet_condition.css";

/** 부르는 쪽이 주는 것 — valuesFor(a1) = 그 칸에 올 수 있는 값 목록(없으면 null → 값 칸) · pills = 이름 붙은 칸 */
export interface ConditionOptions {
  valuesFor(a1: string): (string | number)[] | null;
  pills?(): { name: string; cell: string }[];
}

export { COND_OPS, draftToFormula, formulaToDraft };
export type { CondBranch, CondDraft, CondOp, CondOperand };

/* ── 글 ─────────────────────────────────────────────────────────────────── */

const TEXT = {
  Menu: ["조건 만들기", "Make a condition"],
  Title: ["조건 만들기", "Make a condition"],
  If: ["만약", "If"],
  ElseIf: ["아니면 만약", "Else if"],
  Then: ["→", "→"],
  Otherwise: ["아니면 →", "Otherwise →"],
  AddElseIf: ["+ 아니면 만약", "+ Else if"],
  Remove: ["지움", "Remove"],
  Make: ["만들기", "Make"],
  Cancel: ["취소", "Cancel"],
  Close: ["닫기", "Close"],
  CellPick: ["칸 직접", "A cell"],
  ValuePick: ["값", "A value"],
  Cell: ["칸 주소", "Cell address"],
  Value: ["값", "Value"],
  BadCell: ["칸 주소가 아님 — 예: B2", "Not a cell address — e.g. B2"],
  Target: ["식이 들어갈 칸", "Formula goes into"],
  AsIs: [
    "이 식은 조건 줄로 바꿀 수 없음 — 식 그대로 고침",
    "This formula can't be shown as lines — edit the formula as it is",
  ],
} as const;

const tc = (key: keyof typeof TEXT): string => TEXT[key][currentLanguageIndex === 1 ? 1 : 0];

/* ── 줄 판 ───────────────────────────────────────────────────────────────── */

const OWN = "\u0001cell";
const OWN_VALUE = "\u0001value";

function select(
  options: { value: string; text: string }[],
  value: string,
  onPick: (v: string) => void,
  aria: string,
): HTMLSelectElement {
  const s = el("select", { className: "ui-select ui-select--sm", attrs: { "aria-label": aria } });
  for (const o of options) s.append(el("option", { attrs: { value: o.value }, text: o.text }));
  s.value = value;
  s.addEventListener("change", () => onPick(s.value));
  return s;
}

/** 칸 고르기 — 이름 붙은 칸(알약) 아니면 칸 주소 직접 */
function cellPick(
  opts: ConditionOptions,
  value: string,
  onChange: (cell: string) => void,
  aria: string,
): HTMLElement {
  const pills = opts.pills?.() ?? [];
  const hit = pills.find((p) => p.cell === value);
  const options = [
    ...pills.map((p) => ({ value: p.cell, text: `${p.name} (${p.cell})` })),
    { value: OWN, text: tc("CellPick") },
  ];
  const box = el("span", { className: "ss-cond-pick" });
  const sel = select(options, hit ? value : OWN, (v) => v !== OWN && onChange(v), aria);
  box.append(sel);
  if (!hit) {
    const input = el("input", {
      className: "ui-input ui-input--sm ss-cond-cell",
      attrs: { type: "text", "aria-label": tc("Cell"), placeholder: "B2" },
    });
    input.value = value;
    input.addEventListener("change", () => {
      const m = CELL.exec(input.value.trim().toUpperCase());
      input.classList.toggle("is-bad", !m);
      input.title = m ? "" : tc("BadCell");
      if (m) onChange(`${m[1]}${m[2]}`);
    });
    box.append(input);
  }
  return box;
}

/** 값 쪽 고르기 — 칸 · 알약 · 값(목록이 있으면 고르기) */
function operandPick(
  opts: ConditionOptions,
  o: CondOperand,
  hint: string | null,
  onChange: (o: CondOperand) => void,
  aria: string,
): HTMLElement {
  const box = el("span", { className: "ss-cond-pick" });
  const pills = opts.pills?.() ?? [];
  const isPill = o.kind === "cell" && pills.some((p) => p.cell === o.cell);
  const options = [
    ...pills.map((p) => ({ value: p.cell, text: `${p.name} (${p.cell})` })),
    { value: OWN, text: tc("CellPick") },
    { value: OWN_VALUE, text: tc("ValuePick") },
  ];
  const mode = o.kind === "value" ? OWN_VALUE : isPill ? o.cell : OWN;
  box.append(
    select(
      options,
      mode,
      (v) => {
        if (v === OWN_VALUE) onChange({ kind: "value", value: 0 });
        else if (v === OWN) onChange({ kind: "cell", cell: "B2" });
        else onChange({ kind: "cell", cell: v });
      },
      aria,
    ),
  );
  if (o.kind === "cell" && !isPill) {
    const input = el("input", {
      className: "ui-input ui-input--sm ss-cond-cell",
      attrs: { type: "text", "aria-label": tc("Cell") },
    });
    input.value = o.cell;
    input.addEventListener("change", () => {
      const m = CELL.exec(input.value.trim().toUpperCase());
      input.classList.toggle("is-bad", !m);
      if (m) onChange({ kind: "cell", cell: `${m[1]}${m[2]}` });
    });
    box.append(input);
  }
  if (o.kind === "value") {
    const list = hint ? opts.valuesFor(hint) : null;
    if (list && list.length) {
      const key = (v: string | number): string => `${typeof v}:${v}`;
      box.append(
        select(
          list.map((v) => ({ value: key(v), text: String(v) })),
          key(o.value),
          (k) => {
            const hitv = list.find((v) => key(v) === k);
            if (hitv !== undefined) onChange({ kind: "value", value: hitv });
          },
          tc("Value"),
        ),
      );
    } else {
      const input = el("input", {
        className: "ui-input ui-input--sm ss-cond-value",
        attrs: { type: "text", "aria-label": tc("Value") },
      });
      input.value = String(o.value);
      input.addEventListener("change", () => {
        const t = input.value.trim();
        onChange({ kind: "value", value: t !== "" && Number.isFinite(Number(t)) ? Number(t) : t });
      });
      box.append(input);
    }
  }
  return box;
}

function openJob(
  ctx: SpreadsheetContext,
  opts: ConditionOptions,
  a1: string,
  draft: CondDraft | null,
  existing: string | null,
): void {
  openModal({
    title: `${tc("Title")} — ${a1}`,
    closeLabel: tc("Close"),
    dialogClass: "ss-cond",
    mount: (body, close) => {
      let d: CondDraft = draft ?? {
        branches: [
          {
            left: "B1",
            op: "=",
            right: { kind: "value", value: "" },
            then: { kind: "value", value: 0 },
          },
        ],
        otherwise: { kind: "value", value: 0 },
      };
      if (existing !== null && !draft) {
        body.append(
          el("p", { className: "ss-cond-note", text: tc("AsIs") }),
          el("code", { className: "ss-cond-formula", text: `=${existing}` }),
        );
        return;
      }
      const draw = (): void => {
        const set = (next: CondDraft): void => ((d = next), draw());
        const rows = d.branches.map((b, i) => {
          const edit = (patch: Partial<CondBranch>): void =>
            set({ ...d, branches: d.branches.map((x, j) => (j === i ? { ...x, ...patch } : x)) });
          return el("div", {
            className: "ss-cond-row",
            children: [
              el("span", { className: "ss-cond-label", text: tc(i ? "ElseIf" : "If") }),
              cellPick(opts, b.left, (cell) => edit({ left: cell }), tc("If")),
              select(
                COND_OPS.map((o) => ({ value: o, text: o })),
                b.op,
                (v) => edit({ op: v as CondOp }),
                "op",
              ),
              operandPick(opts, b.right, b.left, (right) => edit({ right }), tc("Value")),
              tc("Then"),
              operandPick(opts, b.then, null, (then) => edit({ then }), tc("Then")),
              d.branches.length > 1
                ? createButton({
                    label: tc("Remove"),
                    variant: "ghost",
                    size: "sm",
                    onClick: () => set({ ...d, branches: d.branches.filter((_, j) => j !== i) }),
                  })
                : "",
            ],
          });
        });
        const last = d.branches[d.branches.length - 1];
        body.replaceChildren(
          ...rows,
          el("div", {
            className: "ss-cond-row",
            children: [
              createButton({
                label: tc("AddElseIf"),
                variant: "ghost",
                size: "sm",
                onClick: () =>
                  set({
                    ...d,
                    branches: [
                      ...d.branches,
                      {
                        left: last.left,
                        op: "=",
                        right: { kind: "value", value: "" },
                        then: { kind: "value", value: 0 },
                      },
                    ],
                  }),
              }),
            ],
          }),
          el("div", {
            className: "ss-cond-row",
            children: [
              el("span", { className: "ss-cond-label", text: tc("Otherwise") }),
              operandPick(
                opts,
                d.otherwise,
                null,
                (otherwise) => set({ ...d, otherwise }),
                tc("Otherwise"),
              ),
            ],
          }),
          el("div", {
            className: "ss-cond-row ss-cond-foot",
            children: [
              el("code", {
                className: "ss-cond-formula",
                text: `${tc("Target")} ${a1}: =${draftToFormula(d)}`,
              }),
              createButton({
                label: tc("Make"),
                variant: "filled",
                size: "sm",
                onClick: () => {
                  const sheet = ctx.sheet();
                  const { 값: _v, ...keep } = sheet.칸[a1] ?? {};
                  ctx.dispatch({
                    종류: "칸",
                    시트: sheet.id,
                    칸: { [a1]: { ...keep, 식: draftToFormula(d) } },
                  });
                  close();
                },
              }),
              createButton({ label: tc("Cancel"), variant: "ghost", size: "sm", onClick: close }),
            ],
          }),
        );
      };
      draw();
    },
  });
}

/** 칸 우클릭에 「조건 만들기」 한 줄 — conditions 를 준 편집기에만 붙음 */
export function attachCondition(ctx: SpreadsheetContext, opts: ConditionOptions): PartHandle {
  let menu: HTMLElement | null = null;
  const close = (): void => {
    menu?.remove();
    menu = null;
    document.removeEventListener("pointerdown", away, true);
  };
  const away = (e: Event): void => {
    if (menu && !menu.contains(e.target as Node)) close();
  };
  const onContext = (e: MouseEvent): void => {
    const hit = ctx.grid.hitTest(e.clientX, e.clientY);
    if (!hit || hit.kind !== "cell" || ctx.readOnly) return;
    e.preventDefault();
    e.stopPropagation();
    close();
    const a1 = toA1(hit.r, hit.c);
    const sheet = ctx.sheet();
    const cell = sheet.칸[a1];
    menu = el("div", { className: "ss-cond-menu" });
    menu.style.left = `${e.clientX}px`;
    menu.style.top = `${e.clientY}px`;
    menu.append(
      createButton({
        label: tc("Menu"),
        variant: "ghost",
        size: "sm",
        onClick: () => {
          close();
          const existing = cell?.식 ?? null;
          const draft = existing !== null ? formulaToDraft(existing) : null;
          openJob(ctx, opts, a1, draft, existing !== null && !draft ? existing : null);
        },
      }),
    );
    document.body.append(menu);
    document.addEventListener("pointerdown", away, true);
  };
  ctx.root.addEventListener("contextmenu", onContext, true);
  return {
    root: null,
    refresh() {},
    destroy() {
      ctx.root.removeEventListener("contextmenu", onContext, true);
      close();
    },
  };
}