(function (root, factory) {
  if (typeof module === 'object' && module.exports) {
    module.exports = factory();
  } else {
    root.ISMIStools = Object.assign(root.ISMIStools || {}, factory());
  }
})(typeof self !== 'undefined' ? self : this, function () {
  'use strict';

  function getPDFLib() {
    return (typeof self !== 'undefined' && self.PDFLib) ||
           (typeof globalThis !== 'undefined' && globalThis.PDFLib);
  }

  function wrapText(text, font, size, maxWidth) {
    const words = String(text).split(/\s+/).filter(Boolean);
    const lines = [];
    let line = '';
    for (const word of words) {
      const candidate = line ? line + ' ' + word : word;
      if (font.widthOfTextAtSize(candidate, size) <= maxWidth) {
        line = candidate;
      } else {
        if (line) lines.push(line);
        line = word;
      }
    }
    if (line) lines.push(line);
    return lines.length ? lines : [''];
  }

  // Format the raw schedule string to match the official PDF style:
  // comma-separate day codes, trim duplicated room suffixes, and split
  // multiple meeting segments onto separate lines.
  function formatSchedule(schedule) {
    let s = String(schedule || '').replace(/\s+/g, ' ').trim();
    if (!s) return s;
    // Collapse duplicated TC anywhere in the string.
    while (/TC\s+TC/.test(s)) s = s.replace(/TC\s+TC/g, 'TC');
    // Join adjacent day codes with commas.
    s = s.replace(/\b(M|Tu|T|W|Th|F|Sa|Su)\s+(M|Tu|T|W|Th|F|Sa|Su)\b/g, '$1,$2');
    // Split concatenated meeting segments (room ending in TC followed by a
    // day code) onto separate lines.
    s = s.replace(/(TC)\s+(?=(?:Su|Sa|Th|Tu|M|W|F|T)\b)/g, '$1\n');
    return s;
  }

  // Reformat a full name to "Lastname, Firstname Middle" when the source gives
  // it as "Firstname Middle Lastname" (no comma). If a comma is already
  // present the name is returned unchanged.
  function formatFullName(name) {
    const s = String(name || '').trim();
    if (!s || /,/.test(s)) return s;
    const parts = s.split(/\s+/);
    if (parts.length < 2) return s;
    const last = parts.pop();
    return last + ', ' + parts.join(' ');
  }
  function wrapLines(text, font, size, maxWidth) {
    const out = [];
    String(text == null ? '' : text).split(/\n/).forEach((seg) => {
      out.push(...wrapText(seg, font, size, maxWidth));
    });
    return out.length ? out : [''];
  }

  // Compact a degree name for display:
  // "BACHELOR OF SCIENCE IN INFORMATION TECHNOLOGY" -> "BS IT".
  // Multi-word fields become initials; single-word fields stay title-cased.
  function compactProgram(program) {
    const s = String(program || '').trim().toUpperCase();
    let m = /^BACHELOR OF SCIENCE IN (.+)$/.exec(s);
    let prefix = 'BS';
    if (!m) {
      m = /^BACHELOR OF ARTS IN (.+)$/.exec(s);
      if (m) prefix = 'AB';
    }
    if (!m) return String(program || '').trim();
    const field = m[1];
    const words = field.split(/\s+/).filter((w) => !/^(AND|OF|THE|IN)$/.test(w));
    if (words.length <= 1) {
      const single = words[0] || field;
      return prefix + ' ' + single.charAt(0).toUpperCase() + single.slice(1).toLowerCase();
    }
    return prefix + ' ' + words.map((w) => w[0]).join('');
  }

  // Map a semester to the official date range label.
  function deriveDateRange(semester) {
    const s = String(semester || '').toUpperCase();
    if (/1ST|FIRST/.test(s)) return 'AUGUST - JANUARY';
    if (/2ND|SECOND/.test(s)) return 'JANUARY - MAY';
    if (/SUMMER/.test(s)) return 'JUNE - JULY';
    return '';
  }

  // Load the bundled header logo (JPEG) in the extension background page.
  // Returns null in Node (tests) or if the asset is unavailable.
  async function loadLogo() {
    try {
      const url = (typeof browser !== 'undefined' && browser.runtime && browser.runtime.getURL)
        ? browser.runtime.getURL('assets/logo.jpeg')
        : null;
      if (!url) return null;
      const resp = await fetch(url);
      if (!resp.ok) return null;
      return new Uint8Array(await resp.arrayBuffer());
    } catch (e) {
      return null;
    }
  }

  // Builds a Letter-size PDF replicating the official ISMIS Study Load layout:
  // header logo, title, semester + date range, date enrolled, a student info
  // row (ID, name, program, Year Level), the course table (GROUP, COURSE,
  // COURSE DESCRIPTION, TEACHER, UNITS, NOTE), and a footer (total under the
  // UNITS column, printed-by). NOTE is the status; schedule is stacked under
  // the course description.
  async function buildStudyLoadPdf(data) {
    const PDFLib = getPDFLib();
    const { PDFDocument, StandardFonts, rgb } = PDFLib;
    const header = data.header || {};
    const courses = data.courses || [];

    const doc = await PDFDocument.create();
    let page = doc.addPage([612, 792]); // Letter
    const font = doc.embedStandardFont(StandardFonts.Helvetica);
    const bold = doc.embedStandardFont(StandardFonts.HelveticaBold);
    const italic = doc.embedStandardFont(StandardFonts.HelveticaOblique);
    const margin = 36;
    const contentWidth = 539.3; // matches reference right edge 575.3
    let y = 792 - 10; // near the very top, matching the reference logo position

    const black = rgb(0, 0, 0);
    const gray = rgb(0.3, 0.3, 0.3);

    const logoBytes = await loadLogo();
    let logoImg = null;
    if (logoBytes) {
      try { logoImg = await doc.embedJpg(logoBytes); } catch (e) { logoImg = null; }
    }

    function center(text, size, f, dy) {
      const w = f.widthOfTextAtSize(text, size);
      page.drawText(text, { x: (612 - w) / 2, y, size, font: f, color: black });
      y -= dy;
    }
    function left(text, size, f, x, dy) {
      page.drawText(text, { x, y, size, font: f, color: black });
      y -= dy;
    }
    function hline(x1, x2, atY) {
      page.drawRectangle({ x: x1, y: atY, width: x2 - x1, height: 0.75, color: black });
    }

    // ---- Header ----
    if (logoImg) {
      const logoW = 292.5;
      const logoH = logoW * (logoImg.height / logoImg.width);
      page.drawImage(logoImg, { x: (612 - logoW) / 2, y: y - logoH, width: logoW, height: logoH });
      y -= logoH + 8;
    }
    center("STUDENT'S STUDY LOAD", 9.5, bold, 14);
    if (header.semester) center(String(header.semester).toUpperCase(), 9, font, 13.5);
    const dateRange = header.dateRange || deriveDateRange(header.semester);
    if (dateRange) center(dateRange, 9, font, 13.5);
    if (header.dateEnrolled) left('Date Enrolled: ' + header.dateEnrolled, 8, italic, margin, 13.5);

    // Student info row, laid out in fixed zones across the page (matching the
    // reference): ID (bold) left, name at ~100, program at ~338, and
    // "Year Level: N" right-aligned to the right content edge (575.3).
    const yearLevelText = header.yearLevel ? 'Year Level: ' + header.yearLevel : '';
    if (header.studentId) page.drawText(header.studentId, { x: margin, y, size: 9, font: bold, color: black });
    if (header.fullName) page.drawText(formatFullName(header.fullName), { x: 100, y, size: 9, font, color: black });
    if (header.program) page.drawText(compactProgram(header.program), { x: 338, y, size: 9, font, color: black });
    if (yearLevelText) {
      const w = font.widthOfTextAtSize(yearLevelText, 9);
      page.drawText(yearLevelText, { x: margin + contentWidth - w, y, size: 9, font, color: black });
    }
    if (header.studentId || header.fullName || header.program || yearLevelText) y -= 14.5;

    // ---- Table: GROUP, COURSE, COURSE DESCRIPTION, TEACHER, UNITS, NOTE ----
    // Column boundaries tuned to the reference PDF (left edge 36, right edge 575.3).
    const cols = [
      { key: 'group', label: 'GROUP', x: 36.0, w: 28.8, align: 'left' },
      { key: 'courseCode', label: 'COURSE', x: 64.8, w: 47.6, align: 'left' },
      { key: 'description', label: 'COURSE DESCRIPTION', x: 112.4, w: 201.4, align: 'left' },
      { key: 'teacher', label: 'TEACHER', x: 313.8, w: 127.6, align: 'left' },
      { key: 'units', label: 'UNITS', x: 441.4, w: 29.5, align: 'right' },
      { key: 'status', label: 'NOTE', x: 470.9, w: 104.4, align: 'right' }
    ];
    const cellSize = 8;
    const headerSize = 8;
    const lineH = 12;

    // Header label positions tuned for Helvetica: left/center aligned within
    // each column so labels never overlap.
    function headerLabelXFor() {
      const widths = {};
      for (const c of cols) {
        const key = c.label.toUpperCase().replace(/\s+/g, '_');
        widths[key] = bold.widthOfTextAtSize(c.label, headerSize);
      }
      return {
        GROUP: cols[0].x,
        COURSE: cols[1].x + 5,
        COURSE_DESCRIPTION: cols[2].x + (cols[2].w - widths.COURSE_DESCRIPTION) / 2,
        TEACHER: cols[3].x + (cols[3].w - widths.TEACHER) / 2,
        UNITS: cols[4].x + (cols[4].w - widths.UNITS) / 2,
        NOTE: cols[5].x + (cols[5].w - widths.NOTE) / 2
      };
    }

    function rowLines(cells) {
      return cols.map((c) => {
        let lines;
        if (c.key === 'description') {
          lines = wrapLines(cells.description, font, cellSize, c.w - 6);
          const sched = String(cells.schedule || '');
          if (sched) lines.push(...wrapLines(sched, font, cellSize, c.w - 6));
        } else {
          lines = wrapLines(cells[c.key], font, cellSize, c.w - 6);
        }
        return lines;
      });
    }

    function drawRow(cells, isHeader) {
      const f = isHeader ? bold : font;
      const size = isHeader ? headerSize : cellSize;
      const linesPerCol = rowLines(cells);

      if (isHeader) {
        // Reference header row: only a top and bottom horizontal rule; no
        // vertical dividers. Text baseline at y; top rule 1.8pt above the
        // text bbox top; bottom rule 11.5pt below the text bbox top. For
        // 8pt Helvetica the text bbox top sits ~8.6pt above the baseline,
        // so the lines are offset by +9.6 (top) and -3.7 (bottom) relative
        // to y. Data rows start 13pt below the header text bbox top.
        const topY = y + 9.6;
        const botY = y - 3.7;
        if (botY < 50) {
          page = doc.addPage([612, 792]);
          y = 792 - 10;
          return drawHeaderRow();
        }

        hline(margin, margin + contentWidth, topY);

        const labelXs = headerLabelXFor();
        for (let i = 0; i < cols.length; i++) {
          const c = cols[i];
          const labelKey = c.label.toUpperCase().replace(/\s+/g, '_');
          const lx = labelXs[labelKey];
          const lines = linesPerCol[i];
          page.drawText(lines[0], { x: lx, y, size, font: f, color: black });
        }

        hline(margin, margin + contentWidth, botY);
        y -= 13.0;
        return true;
      }

      // Data rows: fixed 24.5pt baseline-to-baseline spacing. Description +
      // schedule stack with 12pt line spacing. Expand the row height when
      // the schedule or wrapped description needs more lines.
      const maxLines = Math.max(...linesPerCol.map((l) => l.length));
      const rowHeight = Math.max(24.5, maxLines * lineH + 0.5);
      if (y - rowHeight < 50) {
        page = doc.addPage([612, 792]);
        y = 792 - 10;
        drawHeaderRow();
      }

      for (let i = 0; i < cols.length; i++) {
        const c = cols[i];
        const lines = linesPerCol[i];
        let ty = y;
        for (const line of lines) {
          if (c.key === 'units') {
            const w = f.widthOfTextAtSize(line, size);
            page.drawText(line, { x: c.x + c.w - w, y: ty, size, font: f, color: black });
          } else if (c.key === 'status') {
            page.drawText(line, { x: c.x + 35, y: ty, size, font: f, color: black });
          } else {
            let dx = 3;
            if (c.key === 'group') dx = 12;
            else if (c.key === 'courseCode') dx = 8;
            else if (c.key === 'teacher') dx = 3.5;
            else if (c.key === 'description') dx = 3.5;
            page.drawText(line, { x: c.x + dx, y: ty, size, font: f, color: black });
          }
          ty -= lineH;
        }
      }

      y -= rowHeight;
      return true;
    }

    function drawHeaderRow() {
      const cells = {};
      cols.forEach((c) => { cells[c.key] = c.label; });
      drawRow(cells, true);
    }

    drawHeaderRow();

    for (const course of courses) {
      const cells = {
        group: course.group,
        courseCode: course.courseCode,
        description: course.description,
        schedule: formatSchedule(course.schedule),
        teacher: course.teacher || course.faculty,
        units: course.units,
        status: course.status
      };
      drawRow(cells, false);
    }

    // ---- Footer ----
    if (y < 90) {
      page = doc.addPage([612, 792]);
      y = 792 - 10;
    }
    y -= 12;
    if (data.totalUnits) {
      // Total sits under the UNITS column, right-aligned within it.
      const unitsCol = cols[4];
      const w = bold.widthOfTextAtSize(data.totalUnits, 8);
      // Short underline above the total, spanning the UNITS column.
      hline(unitsCol.x, unitsCol.x + unitsCol.w, y + 9);
      page.drawText(data.totalUnits, { x: unitsCol.x + unitsCol.w - w, y, size: 8, font: bold, color: black });
      y -= 12;
    }
    hline(margin, margin + contentWidth, y);
    y -= 12;
    const printedBy = 'Printed by: ' + (header.studentId || '') + ' on ' + new Date().toLocaleDateString();
    const pw = font.widthOfTextAtSize(printedBy, 8);
    page.drawText(printedBy, { x: margin + contentWidth - pw, y, size: 8, font, color: black });

    return doc.save(); // returns Promise<Uint8Array>
  }

  return { buildStudyLoadPdf, compactProgram, deriveDateRange, formatSchedule, formatFullName };
});