/* /publiser block editor: rich-text toolbar for .md blocks, plain code
 * editing for .html/.php blocks, image upload (cover + inline), and a
 * small Markdown serializer for the bounded tag set the toolbar produces.
 * No external dependencies - contenteditable + document.execCommand for
 * the handful of inline/list commands (still functional everywhere,
 * despite being spec-deprecated), manual DOM ops for block-level toggles.
 */
(function () {
  'use strict';

  document.execCommand('defaultParagraphSeparator', false, 'p');

  // --- Markdown serialization (HTML -> MD, mirrors index.php's MD -> HTML) --

  function serializeChildren(node) {
    return Array.from(node.childNodes).map(serializeNode).join('');
  }

  function serializeNode(node) {
    if (node.nodeType === Node.TEXT_NODE) {
      // Not escaping markdown-significant characters (*, [, ] ...) in plain
      // text: round-tripping literal asterisks/brackets through the parser
      // is a rare, low-severity edge case not worth the added complexity.
      return node.textContent;
    }
    if (node.nodeType !== Node.ELEMENT_NODE) return '';

    if (node.hasAttribute('data-raw-html')) {
      // Non-editable raw-HTML island (see index.php's publiserBlockMdToHtml)
      // - pass the original source through unchanged rather than trying to
      // reconstruct it from the rendered DOM.
      return `\n\n${node.getAttribute('data-raw-html')}\n\n`;
    }

    const tag = node.tagName.toLowerCase();
    switch (tag) {
      case 'strong':
      case 'b': {
        const inner = serializeChildren(node).trim();
        return inner ? `**${inner}**` : '';
      }
      case 'em':
      case 'i': {
        const inner = serializeChildren(node).trim();
        return inner ? `*${inner}*` : '';
      }
      case 'a': {
        const href = node.getAttribute('href') || '';
        const inner = serializeChildren(node).trim();
        return href ? `[${inner}](${href})` : inner;
      }
      case 'img': {
        const file = node.getAttribute('data-filename') || node.getAttribute('src') || '';
        const alt = node.getAttribute('alt') || '';
        return `![${alt}](${file})`;
      }
      case 'br':
        return ' ';
      case 'h2':
        return `\n\n## ${serializeChildren(node).trim()}\n\n`;
      case 'h3':
        return `\n\n### ${serializeChildren(node).trim()}\n\n`;
      case 'blockquote': {
        const text = serializeChildren(node).trim().replace(/\s+/g, ' ');
        return text ? `\n\n> ${text}\n\n` : '';
      }
      case 'ul': {
        const items = Array.from(node.children)
          .filter((c) => c.tagName === 'LI')
          .map((li) => `- ${serializeChildren(li).trim()}`)
          .join('\n');
        return items ? `\n\n${items}\n\n` : '';
      }
      case 'ol': {
        const items = Array.from(node.children)
          .filter((c) => c.tagName === 'LI')
          .map((li, i) => `${i + 1}. ${serializeChildren(li).trim()}`)
          .join('\n');
        return items ? `\n\n${items}\n\n` : '';
      }
      case 'li':
        return serializeChildren(node);
      case 'p':
      case 'div': {
        const inner = serializeChildren(node).trim();
        return inner ? `\n\n${inner}\n\n` : '';
      }
      default:
        return serializeChildren(node);
    }
  }

  function serializeRichText(root) {
    let out = Array.from(root.childNodes).map(serializeNode).join('');
    out = out.replace(/[ \t]+\n/g, '\n');
    out = out.replace(/\n{3,}/g, '\n\n');
    return out.trim();
  }

  // --- dirty tracking ---------------------------------------------------

  function markDirty(richDiv) {
    const block = richDiv.closest('.p-block');
    if (!block) return;
    const dirtyFlag = block.querySelector('.p-dirty-flag');
    const hidden = block.querySelector('.p-block-hidden');
    if (dirtyFlag) dirtyFlag.value = '1';
    if (hidden) hidden.value = serializeRichText(richDiv);
  }

  // --- selection helpers --------------------------------------------------

  function saveSelection(richDiv) {
    const sel = window.getSelection();
    if (!sel || sel.rangeCount === 0) return null;
    const range = sel.getRangeAt(0);
    if (!richDiv.contains(range.startContainer)) return null;
    return range.cloneRange();
  }

  function restoreSelection(range) {
    if (!range) return;
    const sel = window.getSelection();
    sel.removeAllRanges();
    sel.addRange(range);
  }

  function placeCaretAtEnd(el) {
    el.focus();
    const range = document.createRange();
    range.selectNodeContents(el);
    range.collapse(false);
    const sel = window.getSelection();
    sel.removeAllRanges();
    sel.addRange(range);
  }

  function getCurrentBlock(richDiv) {
    const sel = window.getSelection();
    if (!sel.rangeCount) return null;
    let node = sel.getRangeAt(0).startContainer;
    if (node.nodeType === Node.TEXT_NODE) node = node.parentElement;
    while (node && node !== richDiv && !['P', 'DIV', 'H2', 'H3', 'BLOCKQUOTE', 'LI'].includes(node.tagName)) {
      node = node.parentElement;
    }
    return node === richDiv ? null : node;
  }

  function toggleBlockTag(richDiv, tagName) {
    const block = getCurrentBlock(richDiv);
    if (!block) return;
    const targetTag = block.tagName === tagName ? 'P' : tagName;
    const replacement = document.createElement(targetTag);
    replacement.innerHTML = block.innerHTML || '<br>';
    block.replaceWith(replacement);
    placeCaretAtEnd(replacement);
  }

  // --- image upload -------------------------------------------------------

  async function uploadImage(file, form, target) {
    const fd = new FormData();
    fd.append('image', file);
    fd.append('csrf', form.dataset.csrf);
    fd.append('location', form.dataset.location);
    fd.append('section', form.dataset.section);
    fd.append('folder', form.dataset.folder);
    fd.append('target', target);
    try {
      const res = await fetch(form.dataset.uploadUrl, { method: 'POST', body: fd });
      const data = await res.json();
      if (!data.ok) {
        alert('Opplasting feilet: ' + (data.error || 'ukjent feil'));
        return null;
      }
      return data;
    } catch (err) {
      alert('Opplasting feilet: ' + err.message);
      return null;
    }
  }

  function insertImageAtRange(richDiv, range, imgData) {
    const el = document.createElement('img');
    el.src = imgData.url;
    el.alt = '';
    el.setAttribute('data-filename', imgData.filename);

    restoreSelection(range);
    const sel = window.getSelection();
    if (sel.rangeCount && richDiv.contains(sel.getRangeAt(0).startContainer)) {
      const r = sel.getRangeAt(0);
      r.deleteContents();
      r.insertNode(el);
      r.setStartAfter(el);
      r.collapse(true);
      sel.removeAllRanges();
      sel.addRange(r);
    } else {
      richDiv.appendChild(el);
    }
    markDirty(richDiv);
  }

  async function uploadAndInsertImage(richDiv, file, range) {
    const form = richDiv.closest('form');
    const data = await uploadImage(file, form, 'inline');
    if (!data) return;
    insertImageAtRange(richDiv, range, data);
  }

  function triggerImageInsert(richDiv) {
    const savedRange = saveSelection(richDiv);
    const input = document.createElement('input');
    input.type = 'file';
    input.accept = 'image/*';
    input.addEventListener('change', () => {
      if (input.files[0]) uploadAndInsertImage(richDiv, input.files[0], savedRange);
    });
    input.click();
  }

  // --- toolbar commands -----------------------------------------------

  function execToolbarCommand(cmd, richDiv) {
    richDiv.focus();
    switch (cmd) {
      case 'bold':
        document.execCommand('bold');
        break;
      case 'italic':
        document.execCommand('italic');
        break;
      case 'ul':
        document.execCommand('insertUnorderedList');
        break;
      case 'ol':
        document.execCommand('insertOrderedList');
        break;
      case 'link': {
        const url = prompt('Lenke (URL):', 'https://');
        if (url) document.execCommand('createLink', false, url);
        break;
      }
      case 'h2':
        toggleBlockTag(richDiv, 'H2');
        break;
      case 'h3':
        toggleBlockTag(richDiv, 'H3');
        break;
      case 'quote':
        toggleBlockTag(richDiv, 'BLOCKQUOTE');
        break;
      case 'image':
        triggerImageInsert(richDiv);
        return; // markDirty happens after upload completes
      default:
        return;
    }
    markDirty(richDiv);
  }

  // --- wire up rich text blocks -------------------------------------------

  document.querySelectorAll('.p-block').forEach((block) => {
    const richDiv = block.querySelector('.p-richtext');
    if (!richDiv) return;

    richDiv.addEventListener('input', () => markDirty(richDiv));

    richDiv.addEventListener('paste', (e) => {
      const cd = e.clipboardData || window.clipboardData;
      const imageFile = Array.from(cd.files || []).find((f) => f.type.startsWith('image/'));
      e.preventDefault();
      if (imageFile) {
        const sel = window.getSelection();
        const range = sel.rangeCount ? sel.getRangeAt(0).cloneRange() : null;
        uploadAndInsertImage(richDiv, imageFile, range);
        return;
      }
      const text = cd.getData('text/plain');
      document.execCommand('insertText', false, text);
      markDirty(richDiv);
    });

    richDiv.addEventListener('dragover', (e) => {
      e.preventDefault();
      richDiv.classList.add('dragover');
    });
    richDiv.addEventListener('dragleave', () => richDiv.classList.remove('dragover'));
    richDiv.addEventListener('drop', (e) => {
      e.preventDefault();
      richDiv.classList.remove('dragover');
      const file = e.dataTransfer.files && e.dataTransfer.files[0];
      if (!file || !file.type.startsWith('image/')) return;

      let range = null;
      if (document.caretRangeFromPoint) {
        range = document.caretRangeFromPoint(e.clientX, e.clientY);
      } else if (document.caretPositionFromPoint) {
        const pos = document.caretPositionFromPoint(e.clientX, e.clientY);
        if (pos) {
          range = document.createRange();
          range.setStart(pos.offsetNode, pos.offset);
        }
      }
      uploadAndInsertImage(richDiv, file, range);
    });

    block.querySelectorAll('.p-block-toolbar [data-cmd]').forEach((btn) => {
      btn.addEventListener('click', () => execToolbarCommand(btn.dataset.cmd, richDiv));
    });
  });

  // --- cover image dropzone ------------------------------------------------

  function wireCoverDrop(drop) {
    const form = drop.closest('form');
    let input = drop.querySelector('input[type=file]');

    async function handleFile(file) {
      if (!file || !file.type.startsWith('image/')) return;
      const previousContent = drop.innerHTML;
      drop.textContent = 'Laster opp...';
      const data = await uploadImage(file, form, 'cover');
      if (!data) {
        drop.innerHTML = previousContent;
        return;
      }
      drop.innerHTML = '';
      const img = document.createElement('img');
      img.src = data.url;
      drop.appendChild(img);
      const newInput = document.createElement('input');
      newInput.type = 'file';
      newInput.accept = 'image/*';
      newInput.hidden = true;
      drop.appendChild(newInput);
      input = newInput;
      newInput.addEventListener('change', () => handleFile(newInput.files[0]));
    }

    drop.addEventListener('click', () => input && input.click());
    if (input) input.addEventListener('change', () => handleFile(input.files[0]));

    drop.addEventListener('dragover', (e) => {
      e.preventDefault();
      drop.classList.add('dragover');
    });
    drop.addEventListener('dragleave', () => drop.classList.remove('dragover'));
    drop.addEventListener('drop', (e) => {
      e.preventDefault();
      drop.classList.remove('dragover');
      handleFile(e.dataTransfer.files && e.dataTransfer.files[0]);
    });
  }

  document.querySelectorAll('.p-cover-drop').forEach(wireCoverDrop);

  // --- confirmations for destructive submit buttons -----------------------

  document.querySelectorAll('[data-confirm]').forEach((btn) => {
    btn.addEventListener('click', (e) => {
      if (!confirm(btn.dataset.confirm)) e.preventDefault();
    });
  });

  // --- safety net: resync any dirty block right before submit -------------

  const form = document.getElementById('editor-form');
  if (form) {
    form.addEventListener('submit', () => {
      form.querySelectorAll('.p-block[data-type="richtext"]').forEach((block) => {
        const richDiv = block.querySelector('.p-richtext');
        const dirtyFlag = block.querySelector('.p-dirty-flag');
        if (richDiv && dirtyFlag && dirtyFlag.value === '1') {
          block.querySelector('.p-block-hidden').value = serializeRichText(richDiv);
        }
      });
    });
  }
})();