// procurement-xlsx.jsx — спільний рендерер форм закупівель у стилізований .xlsx
// (ExcelJS). Форма описується «блоками» (title/field/section/table/gap), а рендерер
// застосовує єдине оформлення: жирні заголовки, рамки, заливка секцій, перенос.
// Використовується і хабом форм (procurement-forms), і PRF-редактором (procurement-prf).

(function () {
  const GREEN = "FF068B49", SECT = "FFEAF3EE", HEAD = "FFEFF3F1", LINE = "FFBFC9C2";
  const thin = { style: "thin", color: { argb: LINE } };
  const allBorder = { top: thin, left: thin, bottom: thin, right: thin };

  function colLetter(n) { let s = ""; while (n > 0) { const m = (n - 1) % 26; s = String.fromCharCode(65 + m) + s; n = Math.floor((n - 1) / 26); } return s; }

  function save(filename, sheetName, blocks) {
    if (!window.ExcelJS) { alert("Бібліотека Excel (ExcelJS) не завантажилась. Онови сторінку (Ctrl+Shift+R)."); return; }
    const wb = new window.ExcelJS.Workbook();
    const ws = wb.addWorksheet(sheetName || "Form", { views: [{ showGridLines: false }] });

    // кількість колонок = найширша таблиця (мін. 2)
    let totalCols = 2;
    blocks.forEach(b => { if (b.t === "table") totalCols = Math.max(totalCols, b.cols.length); });

    // ширина колонок: з таблиць; для col A враховуємо поля
    const widths = new Array(totalCols).fill(0);
    blocks.forEach(b => { if (b.t === "table") b.cols.forEach((c, i) => { widths[i] = Math.max(widths[i], c.width || 14); }); });
    blocks.forEach(b => { if (b.t === "field") widths[0] = Math.max(widths[0], 34); });
    for (let i = 0; i < totalCols; i++) ws.getColumn(i + 1).width = widths[i] || 16;
    const LAST = colLetter(totalCols);

    let r = 1;
    blocks.forEach(b => {
      if (b.t === "gap") { r++; return; }
      if (b.t === "title") {
        ws.mergeCells(`A${r}:${LAST}${r}`);
        const c = ws.getCell(`A${r}`);
        c.value = b.text;
        c.font = { bold: true, size: 13, color: { argb: "FFFFFFFF" } };
        c.alignment = { horizontal: "center", vertical: "middle", wrapText: true };
        c.fill = { type: "pattern", pattern: "solid", fgColor: { argb: GREEN } };
        ws.getRow(r).height = 28; r++; return;
      }
      if (b.t === "section") {
        ws.mergeCells(`A${r}:${LAST}${r}`);
        const c = ws.getCell(`A${r}`);
        c.value = b.text;
        c.font = { bold: true, size: 11 };
        c.fill = { type: "pattern", pattern: "solid", fgColor: { argb: SECT } };
        c.alignment = { vertical: "middle" };
        ws.getRow(r).height = 20; r++; return;
      }
      if (b.t === "field") {
        const lc = ws.getCell(`A${r}`);
        lc.value = b.label; lc.font = { bold: true }; lc.alignment = { vertical: "middle", wrapText: true };
        if (totalCols >= 3) ws.mergeCells(`B${r}:${LAST}${r}`);
        const vc = ws.getCell(`B${r}`);
        vc.value = b.value == null ? "" : b.value; vc.alignment = { vertical: "middle", wrapText: true };
        r++; return;
      }
      if (b.t === "table") {
        b.cols.forEach((c, i) => {
          const cell = ws.getCell(`${colLetter(i + 1)}${r}`);
          cell.value = c.header;
          cell.font = { bold: true };
          cell.fill = { type: "pattern", pattern: "solid", fgColor: { argb: HEAD } };
          cell.border = allBorder;
          cell.alignment = { vertical: "middle", wrapText: true };
        });
        r++;
        b.rows.forEach(row => {
          for (let i = 0; i < b.cols.length; i++) {
            const cell = ws.getCell(`${colLetter(i + 1)}${r}`);
            const v = row[i];
            cell.value = v == null ? "" : v;
            cell.border = allBorder;
            cell.alignment = { vertical: "top", wrapText: true };
          }
          r++;
        });
        return;
      }
    });

    wb.xlsx.writeBuffer().then(buf => {
      const blob = new Blob([buf], { type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" });
      const url = URL.createObjectURL(blob);
      const a = document.createElement("a");
      a.href = url; a.download = filename; document.body.appendChild(a); a.click(); a.remove();
      setTimeout(() => URL.revokeObjectURL(url), 1500);
    }).catch(e => { console.error("[ERP] xlsx:", e); alert("Помилка генерації Excel."); });
  }

  window.ProcXlsx = {
    save,
    title: (text) => ({ t: "title", text }),
    field: (label, value) => ({ t: "field", label, value: value == null ? "" : value }),
    section: (text) => ({ t: "section", text }),
    table: (cols, rows) => ({ t: "table", cols, rows }),
    gap: () => ({ t: "gap" }),
  };
})();