import { labelFor as outlineLabel, kindLabel as outlineKindLabel } from './outlineLabels.js';

// ---------------------------------------------------------------------------
// Study constants
// ---------------------------------------------------------------------------

export const CHAPTER_COUNTS = {
  GEN:50,EXO:40,LEV:27,NUM:36,DEU:34,JOS:24,JDG:21,RUT:4,
  '1SA':31,'2SA':24,'1KI':22,'2KI':25,'1CH':29,'2CH':36,
  EZR:10,NEH:13,EST:10,JOB:42,PSA:150,PRO:31,ECC:12,SNG:8,
  ISA:66,JER:52,LAM:5,EZK:48,DAN:12,HOS:14,JOL:3,AMO:9,
  OBA:1,JON:4,MIC:7,NAM:3,HAB:3,ZEP:3,HAG:2,ZEC:14,MAL:4,
  MAT:28,MRK:16,LUK:24,JHN:21,ACT:28,ROM:16,'1CO':16,'2CO':13,
  GAL:6,EPH:6,PHP:4,COL:4,'1TH':5,'2TH':3,'1TI':6,'2TI':4,
  TIT:3,PHM:1,HEB:13,JAS:5,'1PE':5,'2PE':3,'1JN':5,'2JN':1,
  '3JN':1,JUD:1,REV:22,
};

export const bookOptions = [
  { name: 'Genesis', abbrev: 'GEN' },
  { name: 'Exodus', abbrev: 'EXO' },
  { name: 'Leviticus', abbrev: 'LEV' },
  { name: 'Numbers', abbrev: 'NUM' },
  { name: 'Deuteronomy', abbrev: 'DEU' },
  { name: 'Joshua', abbrev: 'JOS' },
  { name: 'Judges', abbrev: 'JDG' },
  { name: 'Ruth', abbrev: 'RUT' },
  { name: '1 Samuel', abbrev: '1SA' },
  { name: '2 Samuel', abbrev: '2SA' },
  { name: '1 Kings', abbrev: '1KI' },
  { name: '2 Kings', abbrev: '2KI' },
  { name: '1 Chronicles', abbrev: '1CH' },
  { name: '2 Chronicles', abbrev: '2CH' },
  { name: 'Ezra', abbrev: 'EZR' },
  { name: 'Nehemiah', abbrev: 'NEH' },
  { name: 'Esther', abbrev: 'EST' },
  { name: 'Job', abbrev: 'JOB' },
  { name: 'Psalms', abbrev: 'PSA' },
  { name: 'Proverbs', abbrev: 'PRO' },
  { name: 'Ecclesiastes', abbrev: 'ECC' },
  { name: 'Song', abbrev: 'SNG' },
  { name: 'Isaiah', abbrev: 'ISA' },
  { name: 'Jeremiah', abbrev: 'JER' },
  { name: 'Lamentations', abbrev: 'LAM' },
  { name: 'Ezekiel', abbrev: 'EZK' },
  { name: 'Daniel', abbrev: 'DAN' },
  { name: 'Hosea', abbrev: 'HOS' },
  { name: 'Joel', abbrev: 'JOL' },
  { name: 'Amos', abbrev: 'AMO' },
  { name: 'Obadiah', abbrev: 'OBA' },
  { name: 'Jonah', abbrev: 'JON' },
  { name: 'Micah', abbrev: 'MIC' },
  { name: 'Nahum', abbrev: 'NAM' },
  { name: 'Habakkuk', abbrev: 'HAB' },
  { name: 'Zephaniah', abbrev: 'ZEP' },
  { name: 'Haggai', abbrev: 'HAG' },
  { name: 'Zechariah', abbrev: 'ZEC' },
  { name: 'Malachi', abbrev: 'MAL' },
  { name: 'Matthew', abbrev: 'MAT' },
  { name: 'Mark', abbrev: 'MRK' },
  { name: 'Luke', abbrev: 'LUK' },
  { name: 'John', abbrev: 'JHN' },
  { name: 'Acts', abbrev: 'ACT' },
  { name: 'Romans', abbrev: 'ROM' },
  { name: '1 Corinthians', abbrev: '1CO' },
  { name: '2 Corinthians', abbrev: '2CO' },
  { name: 'Galatians', abbrev: 'GAL' },
  { name: 'Ephesians', abbrev: 'EPH' },
  { name: 'Philippians', abbrev: 'PHP' },
  { name: 'Colossians', abbrev: 'COL' },
  { name: '1 Thessalonians', abbrev: '1TH' },
  { name: '2 Thessalonians', abbrev: '2TH' },
  { name: '1 Timothy', abbrev: '1TI' },
  { name: '2 Timothy', abbrev: '2TI' },
  { name: 'Titus', abbrev: 'TIT' },
  { name: 'Philemon', abbrev: 'PHM' },
  { name: 'Hebrews', abbrev: 'HEB' },
  { name: 'James', abbrev: 'JAS' },
  { name: '1 Peter', abbrev: '1PE' },
  { name: '2 Peter', abbrev: '2PE' },
  { name: '1 John', abbrev: '1JN' },
  { name: '2 John', abbrev: '2JN' },
  { name: '3 John', abbrev: '3JN' },
  { name: 'Jude', abbrev: 'JUD' },
  { name: 'Revelation', abbrev: 'REV' },
];

export const NT_BOOK_NUMBER = {
  MAT: 40, MRK: 41, LUK: 42, JHN: 43, ACT: 44,
  ROM: 45, '1CO': 46, '2CO': 47, GAL: 48, EPH: 49,
  PHP: 50, COL: 51, '1TH': 52, '2TH': 53, '1TI': 54,
  '2TI': 55, TIT: 56, PHM: 57, HEB: 58, JAS: 59,
  '1PE': 60, '2PE': 61, '1JN': 62, '2JN': 63, '3JN': 64,
  JUD: 65, REV: 66,
};

export const storageKey = (translation, book, chapter) => `bible-study-${translation}-${book}-${chapter}`;
export const makeId = () => crypto.randomUUID?.() ?? `${Date.now()}-${Math.random()}`;

// ---------------------------------------------------------------------------
// Format helpers
// ---------------------------------------------------------------------------

export function formatRelativeDate(ts) {
  if (!ts) return '';
  const diff = Date.now() - ts;
  const mins = Math.floor(diff / 60000);
  if (mins < 1) return 'just now';
  if (mins < 60) return `${mins}m ago`;
  const hours = Math.floor(mins / 60);
  if (hours < 24) return `${hours}h ago`;
  const days = Math.floor(hours / 24);
  return `${days}d ago`;
}

export function chunkSpansNextChapter(project, startChapterIndex, chunk) {
  if (!project || !Array.isArray(project.chapters)) return false;
  if (!Number.isInteger(chunk?.spilloverEndVerse)) return false;
  if (startChapterIndex < 0 || startChapterIndex >= project.chapters.length - 1) return false;
  const startChapter = project.chapters[startChapterIndex];
  const nextChapter = project.chapters[startChapterIndex + 1];
  return startChapter?.bookAbbrev && startChapter.bookAbbrev === nextChapter?.bookAbbrev;
}

export function formatChunkReference(project, startChapterIndex, chunk, separator = '-') {
  if (!project || !chunk) return '';
  const startChapter = project.chapters?.[startChapterIndex];
  if (!startChapter) return '';

  if (chunkSpansNextChapter(project, startChapterIndex, chunk)) {
    const nextChapter = project.chapters[startChapterIndex + 1];
    return `${startChapter.book} ${startChapter.chapter}:${chunk.startVerse}${separator}${nextChapter.chapter}:${chunk.spilloverEndVerse}`;
  }

  if (chunk.startVerse === chunk.endVerse) {
    return `${startChapter.book} ${startChapter.chapter}:${chunk.startVerse}`;
  }
  return `${startChapter.book} ${startChapter.chapter}:${chunk.startVerse}${separator}${chunk.endVerse}`;
}

export function getChunkVerseEntries(project, startChapterIndex, chunk) {
  if (!project || !chunk) return [];
  const startChapter = project.chapters?.[startChapterIndex];
  if (!startChapter) return [];

  const startVerses = (startChapter.verses ?? [])
    .filter((verse) => verse.number >= chunk.startVerse && verse.number <= chunk.endVerse)
    .map((verse) => ({
      book: startChapter.book,
      chapter: startChapter.chapter,
      ...verse,
    }));

  if (!chunkSpansNextChapter(project, startChapterIndex, chunk)) {
    return startVerses;
  }

  const nextChapter = project.chapters[startChapterIndex + 1];
  const spilloverVerses = (nextChapter.verses ?? [])
    .filter((verse) => verse.number >= 1 && verse.number <= chunk.spilloverEndVerse)
    .map((verse) => ({
      book: nextChapter.book,
      chapter: nextChapter.chapter,
      ...verse,
    }));

  return [...startVerses, ...spilloverVerses];
}

// ---------------------------------------------------------------------------
// HTML export utilities
// ---------------------------------------------------------------------------

const escHtml = (s) => String(s ?? '').replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;');

export function buildExportHtml(project) {
  const style = `
    body { font-family: Georgia, serif; color: #0f172a; margin: 0; padding: 32px; }
    .page { max-width: 900px; margin: auto; }
    h1, h2 { font-family: Georgia, serif; }
    h1 { margin-bottom: 0.5rem; }
    .chapter-heading { margin: 2rem 0 0.5rem; font-size: 1.2rem; font-weight: 700; border-bottom: 1px solid #cbd5e1; padding-bottom: 0.25rem; }
    .chunk { margin-bottom: 2rem; padding: 1.25rem 1.5rem; border: 1px solid #cbd5e1; border-radius: 0.75rem; background: #ffffff; }
    .verse { margin: 0 0 0.75rem; line-height: 1.7; }
    .scripture-ref { font-weight: 700; margin-bottom: 0.75rem; }
    .oia, .cross-refs, .greek { margin-top: 1rem; }
    .oia-section { margin-bottom: 0.75rem; }
    .greek table { width: 100%; border-collapse: collapse; margin-top: 0.5rem; }
    .greek th, .greek td { border: 1px solid #d1d5db; padding: 0.65rem; text-align: left; }
    .greek th { background: #f8fafc; }
    .definition { margin-top: 0.75rem; font-size: 0.95rem; line-height: 1.6; }
    .outline ul { list-style: none; margin: 0.25rem 0 0.25rem 1.5rem; padding: 0; }
    .outline > ul { margin-left: 0; }
    .outline li { margin: 0.3rem 0; line-height: 1.5; }
    .outline .lbl { display: inline-block; min-width: 2rem; font-weight: 700; }
    .outline .kind { font-size: 0.75em; text-transform: uppercase; letter-spacing: 0.05em; color: #92400e; border: 1px solid #fcd34d; border-radius: 9999px; padding: 0 0.4em; margin-right: 0.3em; }
    .outline .o-note { margin: 0.2rem 0 0 2rem; color: #334155; font-size: 0.95em; }
    .outline .o-quote { margin: 0.3rem 0 0.3rem 2rem; padding-left: 0.75rem; border-left: 3px solid #cbd5e1; font-style: italic; }
    .outline .o-attach { margin-left: 2rem; font-size: 0.85em; color: #64748b; }
    .outline .ref { color: #64748b; font-size: 0.9em; }
    .definition-block { margin-top: 1rem; padding: 1rem; border: 1px solid #e2e8f0; border-radius: 0.75rem; background: #f8fafc; }
    @media print {
      body { padding: 0; }
      .chunk { break-inside: avoid; border-color: #cbd5e1; }
      .chapter-heading { break-after: avoid; }
    }
  `;

  const chapters = Array.isArray(project.chapters) ? project.chapters : [];

  // The outline, if one was written: nested lists, labelled I. / A. / 1. like on the page
  const outlineHtml = (project.outline ?? []).length > 0
    ? `<section class="outline"><h2 class="chapter-heading">Outline</h2>${outlineTimeHtml(project.outline)}${outlineListHtml(project.outline, 0)}</section>`
    : '';

  const chunksHtml = chapters.map((ch, chapterIndex) => {
    const chapterHeader = `<h2 class="chapter-heading">${escHtml(ch.book)} ${escHtml(ch.chapter)}</h2>`;
    const chunkSections = ch.chunks.map((chunk) => {
      const scripture = formatChunkReference(project, chapterIndex, chunk, '-');
      const versesText = getChunkVerseEntries(project, chapterIndex, chunk)
        .map((verse) => `<p class="verse"><strong>${escHtml(verse.chapter)}:${escHtml(verse.number)}</strong> ${escHtml(verse.text)}</p>`)
        .join('');

      const observation = escHtml((chunk.observation ?? '').trim()).replace(/\n/g, '<br />') || '<em>No observation.</em>';
      const interpretation = escHtml((chunk.interpretation ?? '').trim()).replace(/\n/g, '<br />') || '<em>No interpretation.</em>';
      const application = escHtml((chunk.application ?? '').trim()).replace(/\n/g, '<br />') || '<em>No application.</em>';

      const crossRefsHtml = (chunk.crossReferences ?? []).length > 0
        ? `<div class="cross-refs"><strong>CROSS-REFERENCES:</strong> ${chunk.crossReferences.map(escHtml).join(', ')}</div>`
        : '';

      const greekRows = chunk.greekWords.map((word) => `
        <tr>
          <td><strong>${escHtml(word.strongNumber)}</strong></td>
          <td>${escHtml(word.lexeme)}</td>
          <td>${escHtml(word.transliteration)}</td>
          <td>${escHtml(word.partOfSpeech)}</td>
          <td>${escHtml(word.shortDefinition)}</td>
        </tr>
      `).join('');
      const greekTable = wordTableHtml(greekRows);
      const extendedDefinitions = chunk.greekWords
        .map((word) => {
          if (word.definitionHtml) {
            return `
              <div class="definition-block">
                <p><strong>${escHtml(word.strongNumber)} — ${escHtml(word.lexeme)}</strong></p>
                <div class="definition">${word.definitionHtml}</div>
              </div>
            `;
          }
          if ((word.shortDefinition === 'No definition found.' || word.shortDefinition === 'Lookup failed.') && !word.lexeme && !word.definitionHtml && word.query) {
            const raw = word.query.trim();
            const normalized = /^\d+$/.test(raw) ? `G${raw}` : raw.toUpperCase();
            const isStrongs = /^G\d+$/.test(normalized);
            const num = isStrongs ? normalized.slice(1) : null;
            const links = isStrongs && num
              ? `<a href="https://biblehub.com/greek/${num}.htm">BibleHub</a> · <a href="https://www.blueletterbible.org/lexicon/g${num}/esv/0-1/">Blue Letter Bible</a> · <a href="https://www.studylight.org/lexicons/eng/greek/${num}.html">StudyLight</a>`
              : `<a href="https://biblehub.com/search.php?q=${encodeURIComponent(raw)}">BibleHub</a> · <a href="https://www.blueletterbible.org/search/search.cfm?Criteria=${encodeURIComponent(raw)}&t=KJV#s=s_lexiconc">Blue Letter Bible</a>`;
            return `
              <div class="definition-block" style="border-color:#fcd34d;background:#fffbeb;">
                <p><strong>${escHtml(raw)}</strong> — definition not found in auto-lookup</p>
                <p style="margin-top:0.5rem;font-size:0.9rem;">Look it up manually: ${links}</p>
              </div>
            `;
          }
          return '';
        })
        .join('');

      return `
        <section class="chunk">
          <div class="scripture-ref">${escHtml(scripture)}</div>
          ${versesText}
          ${(chunk.outline ?? []).length > 0 ? `<div class="outline"><strong>OUTLINE:</strong>${outlineListHtml(chunk.outline, 0)}</div>` : ''}
          <div class="oia">
            <div class="oia-section"><strong>OBSERVATION:</strong><p>${observation}</p></div>
            <div class="oia-section"><strong>INTERPRETATION:</strong><p>${interpretation}</p></div>
            <div class="oia-section"><strong>APPLICATION:</strong><p>${application}</p></div>
          </div>
          ${crossRefsHtml}
          <div class="greek"><strong>GREEK WORDS:</strong>
            ${greekRows ? greekTable : '<p><em>No Greek word notes.</em></p>'}
            ${extendedDefinitions}
          </div>
        </section>
      `;
    }).join('');
    return chapterHeader + chunkSections;
  }).join('');

  return `<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>${escHtml(project.title)}</title>
  <style>${style}</style>
</head>
<body>
  <div class="page">
    <h1>${escHtml(project.title)}</h1>
    <p>${escHtml(project.translation)}</p>
    ${outlineHtml}
    ${chunksHtml}
  </div>
</body>
</html>`;
}

// <ul> of outline points, each with its label (I., A., 1. …) and passage
function outlineTimeHtml(tree) {
  const total = flattenMinutes(tree);
  return total > 0 ? `<p class="ref">About ${total} minute${total === 1 ? '' : 's'}</p>` : '';
}

function flattenMinutes(nodes) {
  return (nodes ?? []).reduce((sum, n) => sum + (Number.isFinite(n.minutes) ? n.minutes : 0) + flattenMinutes(n.children), 0);
}

function outlineListHtml(nodes, depth) {
  const one = (n, i) => {
    const kind = n.kind ? `<span class="kind">${escHtml(outlineKindLabel(n.kind))}</span> ` : '';
    const mins = Number.isFinite(n.minutes) && n.minutes > 0 ? ` <span class="ref">· ${n.minutes} min</span>` : '';
    const note = (n.note ?? '').trim() ? `<div class="o-note">${escHtml(n.note.trim()).replace(/\n/g, '<br />')}</div>` : '';
    const quote = n.scripture?.text ? `<blockquote class="o-quote">“${escHtml(n.scripture.text)}” — ${escHtml(n.scripture.ref)}</blockquote>` : '';
    const attached = (n.attachments ?? []).length > 0
      ? `<div class="o-attach">${n.attachments.map((a) => `${a.type === 'word' ? 'Word' : 'See'}: ${escHtml(a.label)}${a.detail ? ` — ${escHtml(a.detail)}` : ''}`).join(' · ')}</div>` : '';
    return `<li><span class="lbl">${escHtml(outlineLabel(depth, i))}</span>${kind}${escHtml((n.text ?? '').trim() || '(untitled)')}${n.ref ? ` <span class="ref">(${escHtml(n.ref)})</span>` : ''}${mins}${note}${quote}${attached}${n.children?.length ? outlineListHtml(n.children, depth + 1) : ''}</li>`;
  };
  return `<ul>${nodes.map(one).join('')}</ul>`;
}

// A page of just one outline (for printing or saving as PDF): the title, the passage, the points.
export function buildOutlineHtml({ title, subtitle = '', tree }) {
  const total = flattenMinutes(tree);
  const meta = [subtitle, total > 0 ? `About ${total} minute${total === 1 ? '' : 's'}` : ''].filter(Boolean).join('  ·  ');
  // Simple and calm: paper tones, a serif face, hanging numerals in the accent colour, and generous space.
  const style = `
    :root { --text: #2b2620; --sub: #6b6458; --accent: #a84e27; --line: #e0d8c6; --paper: #faf7f0; }
    * { box-sizing: border-box; }
    body { font-family: Georgia, 'Times New Roman', serif; color: var(--text); background: var(--paper); margin: 0; padding: 48px 24px 64px; -webkit-font-smoothing: antialiased; }
    .page { max-width: 720px; margin: 0 auto; }
    .eyebrow { font: 600 0.72rem/1 system-ui, sans-serif; letter-spacing: 0.18em; text-transform: uppercase; color: var(--accent); margin: 0 0 0.9rem; }
    h1 { margin: 0; font-size: 2.1rem; line-height: 1.2; font-weight: 600; letter-spacing: -0.01em; }
    .sub { font: 0.9rem/1.4 system-ui, sans-serif; color: var(--sub); margin: 0.6rem 0 0; }
    .rule { height: 1px; background: var(--line); margin: 1.6rem 0 0.4rem; border: 0; }
    .outline ul { list-style: none; margin: 0; padding: 0; }
    .outline ul ul { margin-left: 2.4rem; }
    .outline li { margin: 0.55rem 0; line-height: 1.55; font-size: 1.05rem; }
    .outline > ul > li { margin-top: 1.5rem; font-size: 1.15rem; font-weight: 600; }
    .outline > ul > li li { font-weight: 400; font-size: 1.05rem; }
    .lbl { display: inline-block; min-width: 2.4rem; color: var(--accent); font-weight: 600; font-variant-numeric: tabular-nums; }
    .ref { color: var(--sub); font: 0.82em/1 system-ui, sans-serif; font-weight: 400; white-space: nowrap; }
    .kind { font: 600 0.62rem/1 system-ui, sans-serif; text-transform: uppercase; letter-spacing: 0.1em; color: var(--accent); border: 1px solid #e4b9a3; border-radius: 9999px; padding: 0.2em 0.65em; margin-right: 0.5em; vertical-align: 0.15em; }
    .o-note { margin: 0.25rem 0 0 2.4rem; color: var(--sub); font-size: 0.95rem; font-weight: 400; font-style: italic; }
    .o-quote { margin: 0.5rem 0 0.4rem 2.4rem; padding: 0.1rem 0 0.1rem 1rem; border-left: 3px solid #e4b9a3; font-style: italic; font-weight: 400; font-size: 1rem; }
    .o-attach { margin: 0.3rem 0 0 2.4rem; font: 0.8rem/1.5 system-ui, sans-serif; color: var(--sub); font-weight: 400; }
    .foot { margin-top: 3rem; padding-top: 1rem; border-top: 1px solid var(--line); font: 0.72rem/1 system-ui, sans-serif; color: var(--sub); text-align: center; letter-spacing: 0.04em; }
    @media (max-width: 520px) { body { padding: 32px 18px 48px; } h1 { font-size: 1.7rem; } .outline ul ul { margin-left: 1.5rem; } .o-note, .o-quote, .o-attach { margin-left: 1.5rem; } }
    @media print {
      body { background: #fff; padding: 0; }
      .page { max-width: none; }
      li { break-inside: avoid; }
      .outline > ul > li { break-after: avoid; }
    }
  `;
  return `<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1.0" />
  <title>${escHtml(title)} — Outline</title>
  <style>${style}</style>
</head>
<body>
  <div class="page">
    <p class="eyebrow">Outline</p>
    <h1>${escHtml(title)}</h1>
    ${meta ? `<p class="sub">${escHtml(meta)}</p>` : ''}
    <hr class="rule" />
    <div class="outline">${outlineListHtml(tree, 0)}</div>
    <p class="foot">Bible Study Project</p>
  </div>
</body>
</html>`;
}

export function wordTableHtml(rows) {
  return `
    <table>
      <thead>
        <tr>
          <th>Strong's</th>
          <th>Greek</th>
          <th>Transliteration</th>
          <th>Part of Speech</th>
          <th>Short Definition</th>
        </tr>
      </thead>
      <tbody>
        ${rows}
      </tbody>
    </table>
  `;
}

export function extractPartOfSpeech(definitionHtml) {
  const match = /Part\(s\) of speech:\s*([^<]+)/i.exec(definitionHtml || '');
  if (match && match[1]) {
    return match[1].trim();
  }
  return '';
}

export function htmlToPlainText(html = '') {
  const parser = new DOMParser();
  const doc = parser.parseFromString(html, 'text/html');
  const lines = [];
  doc.body.childNodes.forEach((node) => {
    if (node.nodeType === Node.TEXT_NODE) {
      lines.push(node.textContent || '');
      return;
    }
    if (node.nodeName === 'BR' || node.nodeName === 'P') {
      lines.push(node.textContent || '');
      lines.push('\n');
      return;
    }
    lines.push(node.textContent || '');
  });
  return lines.join('').replace(/\n{2,}/g, '\n').trim();
}

export function renderVerseContent(content) {
  if (typeof content === 'string') {
    return content;
  }
  if (Array.isArray(content)) {
    // A footnote marker ({ noteId }) often sits where the source had a space ("light,” [note] and there
    // was light"), which would run the words together. Put the space back when nothing else supplies one.
    let out = '';
    let afterNote = false;
    for (const part of content) {
      const piece = renderVerseContent(part);
      if (piece === '' && part && typeof part === 'object' && 'noteId' in part) { afterNote = true; continue; }
      if (afterNote && out && piece && !/\s$/.test(out) && /^[\p{L}\p{N}“‘"'(]/u.test(piece)) out += ' ';
      afterNote = false;
      out += piece;
    }
    return out;
  }
  if (content && typeof content === 'object') {
    if (content.lineBreak) {
      return '\n';
    }
    if (content.type === 'line_break') {
      return '\n';
    }
    if (Array.isArray(content.content)) {
      return renderVerseContent(content.content);
    }
    if (typeof content.text === 'string') {
      return content.text;
    }
    return '';
  }
  return '';
}

export function parseBibleChapter(data) {
  if (data?.verses && Array.isArray(data.verses)) {
    return data.verses.map((verse) => ({
      number: verse.number,
      text: verse.text,
    }));
  }

  const chapterContents = data?.chapter?.content;
  if (!Array.isArray(chapterContents)) {
    return [];
  }

  return chapterContents
    .filter((item) => item?.type === 'verse')
    .map((item) => ({
      number: item.number,
      text: renderVerseContent(item.content).replace(/\s+/g, ' ').trim(),
    }));
}

// ---------------------------------------------------------------------------
// Storage helpers
// ---------------------------------------------------------------------------

const INDEX_KEY_LEGACY = 'bible-study-index';
const projectKeyLegacy = (id) => `bible-study-project-${id}`;

let activeStorageUserId = null;

export function indexKey() {
  return activeStorageUserId ? `bible-study-index:${activeStorageUserId}` : INDEX_KEY_LEGACY;
}

export function projectKey(id) {
  return activeStorageUserId ? `bible-study-project:${activeStorageUserId}:${id}` : projectKeyLegacy(id);
}

export function loadProjectIndex() {
  try {
    const raw = window.localStorage.getItem(indexKey());
    return raw ? JSON.parse(raw) : [];
  } catch {
    return [];
  }
}

function migrateLegacyLocalDataToUser(userId) {
  if (!userId || window.localStorage.getItem(`bible-study-index:${userId}`)) return;
  const legacyRaw = window.localStorage.getItem(INDEX_KEY_LEGACY);
  if (!legacyRaw) return;
  try {
    const legacyIndex = JSON.parse(legacyRaw) ?? [];
    legacyIndex.forEach((entry) => {
      const raw = window.localStorage.getItem(projectKeyLegacy(entry.id));
      if (raw != null) {
        window.localStorage.setItem(`bible-study-project:${userId}:${entry.id}`, raw);
        window.localStorage.removeItem(projectKeyLegacy(entry.id));
      }
    });
    window.localStorage.setItem(`bible-study-index:${userId}`, legacyRaw);
    window.localStorage.removeItem(INDEX_KEY_LEGACY);
  } catch {
    // Leave legacy data in place if anything goes wrong
  }
}

export function switchStorageUser(userId) {
  activeStorageUserId = userId ?? null;
  if (userId) migrateLegacyLocalDataToUser(userId);
  return loadProjectIndex();
}

// ---------------------------------------------------------------------------
// Components
// ---------------------------------------------------------------------------

export function BookmarkIcon({ filled }) {
  return (
    <svg viewBox="0 0 20 20" width="16" height="16" fill={filled ? 'currentColor' : 'none'} stroke="currentColor" strokeWidth="1.6">
      <path d="M5 3.5C5 2.67 5.67 2 6.5 2h7c.83 0 1.5.67 1.5 1.5v14l-5-3.5-5 3.5v-14z" strokeLinejoin="round" />
    </svg>
  );
}

export function CopyIcon() {
  return (
    <svg viewBox="0 0 20 20" width="16" height="16" fill="none" stroke="currentColor" strokeWidth="1.6">
      <rect x="7" y="7" width="10" height="11" rx="1.5" />
      <path d="M4.5 13.5h-1A1.5 1.5 0 0 1 2 12V3.5A1.5 1.5 0 0 1 3.5 2H12a1.5 1.5 0 0 1 1.5 1.5v1" strokeLinecap="round" strokeLinejoin="round" />
    </svg>
  );
}

export function buildPronunciationGuide(project) {
  const chapters = Array.isArray(project?.chapters) ? project.chapters : [];
  const lines = [];
  chapters.forEach((ch) => {
    ch.chunks.forEach((chunk) => {
      (chunk.greekWords ?? []).forEach((word) => {
        const gloss = word.shortDefinition || word.englishGloss || '';
        const lexeme = word.lexeme || '';
        const translit = word.transliteration || '';
        if (!lexeme && !translit) return;
        const label = gloss ? `${gloss} — ` : '';
        lines.push(`${label}${lexeme}${translit ? ` (${translit})` : ''}`);
      });
    });
  });
  if (lines.length === 0) return 'No Greek/Hebrew words collected yet.';
  return lines.join('\n');
}