import { readDocx } from "./parser.js";

const toIso = (d, m, y) =>
  `${y}-${m.padStart(2, "0")}-${d.padStart(2, "0")}`;
const time = (h, m) => `${h.padStart(2, "0")}:${m}`;

// "Расписание белых и зеленых недель.docx": pairs of cells "номер | дд.мм.гггг-дд.мм.гггг".
export function parseWeeksDocx(buffer) {
  const { tables } = readDocx(buffer);
  const weeks = [];
  for (const { rows } of tables) {
    const header = rows[0] || [];
    const colorOf = (col) => {
      const label = header.find((c) => c.col === col)?.text.toLowerCase() || "";
      return /зел[её]н/.test(label) ? "green" : /бел/.test(label) ? "white" : null;
    };
    for (const row of rows)
      row.forEach((cell, i) => {
        const range = cell.text.match(
          /(\d{1,2})\.(\d{1,2})\.(\d{4})\s*[-–]\s*(\d{1,2})\.(\d{1,2})\.(\d{4})/,
        );
        const n = Number(row[i - 1]?.text.match(/^\d{1,2}$/)?.[0]);
        if (!range || !n) return;
        weeks.push({
          n,
          start: toIso(range[1], range[2], range[3]),
          end: toIso(range[4], range[5], range[6]),
          color: colorOf(cell.col) || (n % 2 ? "white" : "green"),
        });
      });
  }
  weeks.sort((a, b) => a.start.localeCompare(b.start));
  if (!weeks.length)
    throw new Error("Таблица недель не распознана.");
  return weeks;
}

// "Расписание звонков.docx": "1 пара | 8.30 – 9.10 9.15 – 9.55".
export function parseBellsDocx(buffer) {
  const { tables } = readDocx(buffer);
  const bells = [];
  for (const { rows } of tables)
    for (const row of rows) {
      const pair = Number(row[0]?.text.match(/^(\d)\s*пара/i)?.[1]);
      const times = [
        ...row
          .slice(1)
          .map((c) => c.text)
          .join(" ")
          .matchAll(/([0-2]?\d)[.:]([0-5]\d)/g),
      ].map((m) => time(m[1], m[2]));
      if (!pair || times.length < 2) continue;
      const halves = [];
      for (let i = 0; i + 1 < times.length; i += 2)
        halves.push([times[i], times[i + 1]]);
      bells.push({ pair, start: times[0], end: times.at(-1), halves });
    }
  return bells.sort((a, b) => a.pair - b.pair);
}