fix formatting

lib/Epub/Epub/ParsedText.cpp

@@ -19,6 +19,23 @@ namespace {
 constexpr char SOFT_HYPHEN_UTF8[] = "\xC2\xAD";
 constexpr size_t SOFT_HYPHEN_BYTES = 2;
 
+// Check if a character is punctuation that should attach to the previous word
+// (no space before it). Includes sentence punctuation and closing quotes.
+// Excludes brackets/parens to avoid false positives with decorative patterns like "[ 1 ]".
+bool isAttachingPunctuation(const char c) {
+  return c == '.' || c == ',' || c == '!' || c == '?' || c == ';' || c == ':' || c == '"' || c == '\'';
+}
+
+// Check if a word consists entirely of punctuation that should attach to the previous word
+bool isAttachingPunctuationWord(const std::string& word) {
+  if (word.empty()) return false;
+  // Check if word starts with attaching punctuation and is short (to avoid false positives)
+  if (isAttachingPunctuation(word[0]) && word.size() <= 3) {
+    return true;
+  }
+  return false;
+}
+
 bool containsSoftHyphen(const std::string& word) { return word.find(SOFT_HYPHEN_UTF8) != std::string::npos; }
 
 // Removes every soft hyphen in-place so rendered glyphs match measured widths.
@@ -369,10 +386,20 @@ void ParsedText::extractLine(const size_t breakIndex, const int pageWidth, const
                                   ? blockStyle.textIndent
                                   : 0;
 
-  // Calculate total word width for this line
+  // Calculate total word width for this line and count actual word gaps
+  // (punctuation that attaches to previous word doesn't count as a gap)
+  // Note: words list starts at the beginning because previous lines were spliced out
   int lineWordWidthSum = 0;
-  for (size_t i = lastBreakAt; i < lineBreak; i++) {
+  size_t actualGapCount = 0;
-    lineWordWidthSum += wordWidths[i];
+  auto countWordIt = words.begin();
+
+  for (size_t wordIdx = 0; wordIdx < lineWordCount; wordIdx++) {
+    lineWordWidthSum += wordWidths[lastBreakAt + wordIdx];
+    // Count gaps: each word after the first creates a gap, unless it's attaching punctuation
+    if (wordIdx > 0 && !isAttachingPunctuationWord(*countWordIt)) {
+      actualGapCount++;
+    }
+    ++countWordIt;
   }
 
   // Calculate spacing (account for indent reducing effective page width on first line)
@@ -382,24 +409,37 @@ void ParsedText::extractLine(const size_t breakIndex, const int pageWidth, const
   int spacing = spaceWidth;
   const bool isLastLine = breakIndex == lineBreakIndices.size() - 1;
 
-  if (style == TextBlock::JUSTIFIED && !isLastLine && lineWordCount >= 2) {
+  // For justified text, calculate spacing based on actual gap count
-    spacing = spareSpace / (lineWordCount - 1);
+  if (style == TextBlock::JUSTIFIED && !isLastLine && actualGapCount >= 1) {
+    spacing = spareSpace / static_cast<int>(actualGapCount);
   }
 
   // Calculate initial x position (first line starts at indent for left/justified text)
   auto xpos = static_cast<uint16_t>(firstLineIndent);
   if (style == TextBlock::RIGHT_ALIGN) {
-    xpos = spareSpace - (lineWordCount - 1) * spaceWidth;
+    xpos = spareSpace - static_cast<int>(actualGapCount) * spaceWidth;
   } else if (style == TextBlock::CENTER_ALIGN) {
-    xpos = (spareSpace - (lineWordCount - 1) * spaceWidth) / 2;
+    xpos = (spareSpace - static_cast<int>(actualGapCount) * spaceWidth) / 2;
   }
 
   // Pre-calculate X positions for words
+  // Punctuation that attaches to the previous word doesn't get space before it
+  // Note: words list starts at the beginning because previous lines were spliced out
   std::list<uint16_t> lineXPos;
-  for (size_t i = lastBreakAt; i < lineBreak; i++) {
+  auto wordIt = words.begin();
-    const uint16_t currentWordWidth = wordWidths[i];
+
+  for (size_t wordIdx = 0; wordIdx < lineWordCount; wordIdx++) {
+    const uint16_t currentWordWidth = wordWidths[lastBreakAt + wordIdx];
+
     lineXPos.push_back(xpos);
-    xpos += currentWordWidth + spacing;
+
+    // Add spacing after this word, unless the next word is attaching punctuation
+    auto nextWordIt = wordIt;
+    ++nextWordIt;
+    const bool nextIsAttachingPunctuation = wordIdx + 1 < lineWordCount && isAttachingPunctuationWord(*nextWordIt);
+
+    xpos += currentWordWidth + (nextIsAttachingPunctuation ? 0 : spacing);
+    ++wordIt;
   }
 
   // Iterators always start at the beginning as we are moving content with splice below

lib/Epub/Epub/css/CssParser.cpp

@@ -253,15 +253,12 @@ CssTextDecoration CssParser::interpretDecoration(const std::string& val) {
   return CssTextDecoration::None;
 }
 
-float CssParser::interpretLength(const std::string& val, const float emSize) {
+CssLength CssParser::interpretLength(const std::string& val) {
   const std::string v = normalized(val);
-  if (v.empty()) return 0.0f;
+  if (v.empty()) return CssLength{};
-
-  // Determine unit and multiplier
-  float multiplier = 1.0f;
-  size_t unitStart = v.size();
 
   // Find where the number ends
+  size_t unitStart = v.size();
   for (size_t i = 0; i < v.size(); ++i) {
     const char c = v[i];
     if (!std::isdigit(c) && c != '.' && c != '-' && c != '+') {
@@ -273,20 +270,23 @@ float CssParser::interpretLength(const std::string& val, const float emSize) {
   const std::string numPart = v.substr(0, unitStart);
   const std::string unitPart = v.substr(unitStart);
 
-  // Handle units
+  // Parse numeric value
-  if (unitPart == "em" || unitPart == "rem") {
-    multiplier = emSize;
-  } else if (unitPart == "pt") {
-    multiplier = 1.33f;  // Approximate pt to px conversion
-  }
-  // px is default (multiplier = 1.0)
-
   char* endPtr = nullptr;
   const float numericValue = std::strtof(numPart.c_str(), &endPtr);
+  if (endPtr == numPart.c_str()) return CssLength{};  // No number parsed
 
-  if (endPtr == numPart.c_str()) return 0.0f;  // No number parsed
+  // Determine unit type (preserve for deferred resolution)
+  auto unit = CssUnit::Pixels;
+  if (unitPart == "em") {
+    unit = CssUnit::Em;
+  } else if (unitPart == "rem") {
+    unit = CssUnit::Rem;
+  } else if (unitPart == "pt") {
+    unit = CssUnit::Points;
+  }
+  // px and unitless default to Pixels
 
-  return numericValue * multiplier;
+  return CssLength{numericValue, unit};
 }
 
 int8_t CssParser::interpretSpacing(const std::string& val) {
@@ -367,28 +367,28 @@ CssStyle CssParser::parseDeclarations(const std::string& declBlock) {
       style.decoration = interpretDecoration(propValue);
       style.defined.decoration = 1;
     } else if (propName == "text-indent") {
-      style.indentPixels = interpretLength(propValue);
+      style.indent = interpretLength(propValue);
       style.defined.indent = 1;
     } else if (propName == "margin-top") {
-      style.marginTop = static_cast<int16_t>(interpretLength(propValue));
+      style.marginTop = interpretLength(propValue);
       style.defined.marginTop = 1;
     } else if (propName == "margin-bottom") {
-      style.marginBottom = static_cast<int16_t>(interpretLength(propValue));
+      style.marginBottom = interpretLength(propValue);
       style.defined.marginBottom = 1;
     } else if (propName == "margin-left") {
-      style.marginLeft = static_cast<int16_t>(interpretLength(propValue));
+      style.marginLeft = interpretLength(propValue);
       style.defined.marginLeft = 1;
     } else if (propName == "margin-right") {
-      style.marginRight = static_cast<int16_t>(interpretLength(propValue));
+      style.marginRight = interpretLength(propValue);
       style.defined.marginRight = 1;
     } else if (propName == "margin") {
       // Shorthand: 1-4 values for top, right, bottom, left
       const auto values = splitWhitespace(propValue);
       if (!values.empty()) {
-        const auto top = static_cast<int16_t>(interpretLength(values[0]));
+        const CssLength top = interpretLength(values[0]);
-        const int16_t right = values.size() >= 2 ? static_cast<int16_t>(interpretLength(values[1])) : top;
+        const CssLength right = values.size() >= 2 ? interpretLength(values[1]) : top;
-        const int16_t bottom = values.size() >= 3 ? static_cast<int16_t>(interpretLength(values[2])) : top;
+        const CssLength bottom = values.size() >= 3 ? interpretLength(values[2]) : top;
-        const int16_t left = values.size() >= 4 ? static_cast<int16_t>(interpretLength(values[3])) : right;
+        const CssLength left = values.size() >= 4 ? interpretLength(values[3]) : right;
         style.marginTop = top;
         style.marginRight = right;
         style.marginBottom = bottom;
@@ -396,25 +396,25 @@ CssStyle CssParser::parseDeclarations(const std::string& declBlock) {
         style.defined.marginTop = style.defined.marginRight = style.defined.marginBottom = style.defined.marginLeft = 1;
       }
     } else if (propName == "padding-top") {
-      style.paddingTop = static_cast<int16_t>(interpretLength(propValue));
+      style.paddingTop = interpretLength(propValue);
       style.defined.paddingTop = 1;
     } else if (propName == "padding-bottom") {
-      style.paddingBottom = static_cast<int16_t>(interpretLength(propValue));
+      style.paddingBottom = interpretLength(propValue);
       style.defined.paddingBottom = 1;
     } else if (propName == "padding-left") {
-      style.paddingLeft = static_cast<int16_t>(interpretLength(propValue));
+      style.paddingLeft = interpretLength(propValue);
       style.defined.paddingLeft = 1;
     } else if (propName == "padding-right") {
-      style.paddingRight = static_cast<int16_t>(interpretLength(propValue));
+      style.paddingRight = interpretLength(propValue);
       style.defined.paddingRight = 1;
     } else if (propName == "padding") {
       // Shorthand: 1-4 values for top, right, bottom, left
       const auto values = splitWhitespace(propValue);
       if (!values.empty()) {
-        const auto top = static_cast<int16_t>(interpretLength(values[0]));
+        const CssLength top = interpretLength(values[0]);
-        const int16_t right = values.size() >= 2 ? static_cast<int16_t>(interpretLength(values[1])) : top;
+        const CssLength right = values.size() >= 2 ? interpretLength(values[1]) : top;
-        const int16_t bottom = values.size() >= 3 ? static_cast<int16_t>(interpretLength(values[2])) : top;
+        const CssLength bottom = values.size() >= 3 ? interpretLength(values[2]) : top;
-        const int16_t left = values.size() >= 4 ? static_cast<int16_t>(interpretLength(values[3])) : right;
+        const CssLength left = values.size() >= 4 ? interpretLength(values[3]) : right;
         style.paddingTop = top;
         style.paddingRight = right;
         style.paddingBottom = bottom;

lib/Epub/Epub/css/CssParser.h

@@ -89,7 +89,7 @@ class CssParser {
   static CssFontStyle interpretFontStyle(const std::string& val);
   static CssFontWeight interpretFontWeight(const std::string& val);
   static CssTextDecoration interpretDecoration(const std::string& val);
-  static float interpretLength(const std::string& val, float emSize = 16.0f);
+  static CssLength interpretLength(const std::string& val);
   static int8_t interpretSpacing(const std::string& val);
 
   // String utilities

lib/Epub/Epub/css/CssStyle.h

@@ -5,6 +5,37 @@
 // Text alignment options matching CSS text-align property
 enum class TextAlign : uint8_t { None = 0, Left = 1, Right = 2, Center = 3, Justify = 4 };
 
+// CSS length unit types
+enum class CssUnit : uint8_t { Pixels = 0, Em = 1, Rem = 2, Points = 3 };
+
+// Represents a CSS length value with its unit, allowing deferred resolution to pixels
+struct CssLength {
+  float value = 0.0f;
+  CssUnit unit = CssUnit::Pixels;
+
+  CssLength() = default;
+  CssLength(const float v, const CssUnit u) : value(v), unit(u) {}
+
+  // Convenience constructor for pixel values (most common case)
+  explicit CssLength(const float pixels) : value(pixels) {}
+
+  // Resolve to pixels given the current em size (font line height)
+  [[nodiscard]] float toPixels(const float emSize) const {
+    switch (unit) {
+      case CssUnit::Em:
+      case CssUnit::Rem:
+        return value * emSize;
+      case CssUnit::Points:
+        return value * 1.33f;  // Approximate pt to px conversion
+      default:
+        return value;
+    }
+  }
+
+  // Resolve to int16_t pixels (for BlockStyle fields)
+  [[nodiscard]] int16_t toPixelsInt16(const float emSize) const { return static_cast<int16_t>(toPixels(emSize)); }
+};
+
 // Font style options matching CSS font-style property
 enum class CssFontStyle : uint8_t { Normal = 0, Italic = 1 };
 
@@ -61,21 +92,22 @@ struct CssPropertyFlags {
 
 // Represents a collection of CSS style properties
 // Only stores properties relevant to e-ink text rendering
+// Length values are stored as CssLength (value + unit) for deferred resolution
 struct CssStyle {
   TextAlign alignment = TextAlign::None;
   CssFontStyle fontStyle = CssFontStyle::Normal;
   CssFontWeight fontWeight = CssFontWeight::Normal;
   CssTextDecoration decoration = CssTextDecoration::None;
 
-  float indentPixels = 0.0f;  // First-line indent in pixels
+  CssLength indent;         // First-line indent (deferred resolution)
-  int16_t marginTop = 0;      // Vertical spacing before block (in pixels)
+  CssLength marginTop;      // Vertical spacing before block
-  int16_t marginBottom = 0;   // Vertical spacing after block (in pixels)
+  CssLength marginBottom;   // Vertical spacing after block
-  int16_t marginLeft = 0;     // Horizontal spacing left of block (in pixels)
+  CssLength marginLeft;     // Horizontal spacing left of block
-  int16_t marginRight = 0;    // Horizontal spacing right of block (in pixels)
+  CssLength marginRight;    // Horizontal spacing right of block
-  int16_t paddingTop = 0;     // Padding before (in pixels)
+  CssLength paddingTop;     // Padding before
-  int16_t paddingBottom = 0;  // Padding after (in pixels)
+  CssLength paddingBottom;  // Padding after
-  int16_t paddingLeft = 0;    // Padding left (in pixels)
+  CssLength paddingLeft;    // Padding left
-  int16_t paddingRight = 0;   // Padding right (in pixels)
+  CssLength paddingRight;   // Padding right
 
   CssPropertyFlags defined;  // Tracks which properties were explicitly set
 
@@ -99,7 +131,7 @@ struct CssStyle {
       defined.decoration = 1;
     }
     if (base.defined.indent) {
-      indentPixels = base.indentPixels;
+      indent = base.indent;
       defined.indent = 1;
     }
     if (base.defined.marginTop) {
@@ -159,9 +191,9 @@ struct CssStyle {
     fontStyle = CssFontStyle::Normal;
     fontWeight = CssFontWeight::Normal;
     decoration = CssTextDecoration::None;
-    indentPixels = 0.0f;
+    indent = CssLength{};
-    marginTop = marginBottom = marginLeft = marginRight = 0;
+    marginTop = marginBottom = marginLeft = marginRight = CssLength{};
-    paddingTop = paddingBottom = paddingLeft = paddingRight = 0;
+    paddingTop = paddingBottom = paddingLeft = paddingRight = CssLength{};
     defined.clearAll();
   }
 };

lib/Epub/Epub/parsers/ChapterHtmlSlimParser.cpp

@@ -43,21 +43,28 @@ bool matches(const char* tag_name, const char* possible_tags[], const int possib
   return false;
 }
 
-// Create a BlockStyle from CSS style properties
+// Create a BlockStyle from CSS style properties, resolving CssLength values to pixels
-BlockStyle createBlockStyleFromCss(const CssStyle& cssStyle) {
+// emSize is the current font line height, used for em/rem unit conversion
+BlockStyle createBlockStyleFromCss(const CssStyle& cssStyle, const float emSize) {
   BlockStyle blockStyle;
+  // Resolve all CssLength values to pixels using the current font's em size
+  const int16_t marginTopPx = cssStyle.marginTop.toPixelsInt16(emSize);
+  const int16_t marginBottomPx = cssStyle.marginBottom.toPixelsInt16(emSize);
+  const int16_t paddingTopPx = cssStyle.paddingTop.toPixelsInt16(emSize);
+  const int16_t paddingBottomPx = cssStyle.paddingBottom.toPixelsInt16(emSize);
+
   // Vertical: combine margin and padding for top/bottom spacing
-  blockStyle.marginTop = static_cast<int16_t>(cssStyle.marginTop + cssStyle.paddingTop);
+  blockStyle.marginTop = static_cast<int16_t>(marginTopPx + paddingTopPx);
-  blockStyle.marginBottom = static_cast<int16_t>(cssStyle.marginBottom + cssStyle.paddingBottom);
+  blockStyle.marginBottom = static_cast<int16_t>(marginBottomPx + paddingBottomPx);
-  blockStyle.paddingTop = cssStyle.paddingTop;
+  blockStyle.paddingTop = paddingTopPx;
-  blockStyle.paddingBottom = cssStyle.paddingBottom;
+  blockStyle.paddingBottom = paddingBottomPx;
   // Horizontal: store margin and padding separately for layout calculations
-  blockStyle.marginLeft = cssStyle.marginLeft;
+  blockStyle.marginLeft = cssStyle.marginLeft.toPixelsInt16(emSize);
-  blockStyle.marginRight = cssStyle.marginRight;
+  blockStyle.marginRight = cssStyle.marginRight.toPixelsInt16(emSize);
-  blockStyle.paddingLeft = cssStyle.paddingLeft;
+  blockStyle.paddingLeft = cssStyle.paddingLeft.toPixelsInt16(emSize);
-  blockStyle.paddingRight = cssStyle.paddingRight;
+  blockStyle.paddingRight = cssStyle.paddingRight.toPixelsInt16(emSize);
   // Text indent
-  blockStyle.textIndent = static_cast<int16_t>(cssStyle.indentPixels);
+  blockStyle.textIndent = cssStyle.indent.toPixelsInt16(emSize);
   blockStyle.textIndentDefined = cssStyle.defined.indent;
   return blockStyle;
 }
@@ -106,13 +113,44 @@ void ChapterHtmlSlimParser::flushPartWordBuffer() {
   partWordBufferIndex = 0;
 }
 
+// Merge block styles for nested block elements
+// When a child block element is inside a parent with no direct text content,
+// we accumulate their margins so nested containers properly contribute spacing
+BlockStyle mergeBlockStyles(const BlockStyle& parent, const BlockStyle& child) {
+  BlockStyle merged;
+  // Vertical margins: sum them (nested blocks create additive spacing)
+  merged.marginTop = static_cast<int16_t>(parent.marginTop + child.marginTop);
+  merged.marginBottom = static_cast<int16_t>(parent.marginBottom + child.marginBottom);
+  // Horizontal margins: sum them (nested blocks create cumulative indentation)
+  merged.marginLeft = static_cast<int16_t>(parent.marginLeft + child.marginLeft);
+  merged.marginRight = static_cast<int16_t>(parent.marginRight + child.marginRight);
+  // Padding: sum them
+  merged.paddingTop = static_cast<int16_t>(parent.paddingTop + child.paddingTop);
+  merged.paddingBottom = static_cast<int16_t>(parent.paddingBottom + child.paddingBottom);
+  merged.paddingLeft = static_cast<int16_t>(parent.paddingLeft + child.paddingLeft);
+  merged.paddingRight = static_cast<int16_t>(parent.paddingRight + child.paddingRight);
+  // Text indent: use child's if defined, otherwise inherit parent's
+  if (child.textIndentDefined) {
+    merged.textIndent = child.textIndent;
+    merged.textIndentDefined = true;
+  } else if (parent.textIndentDefined) {
+    merged.textIndent = parent.textIndent;
+    merged.textIndentDefined = true;
+  }
+  return merged;
+}
+
 // start a new text block if needed
 void ChapterHtmlSlimParser::startNewTextBlock(const TextBlock::Style style, const BlockStyle& blockStyle) {
   if (currentTextBlock) {
     // already have a text block running and it is empty - just reuse it
     if (currentTextBlock->isEmpty()) {
       currentTextBlock->setStyle(style);
-      currentTextBlock->setBlockStyle(blockStyle);
+      // Merge with existing block style to accumulate margins from parent block elements
+      // This handles cases like <div margin-bottom:2em><h1>text</h1></div> where the
+      // div's margin should be preserved even though it has no direct text content
+      const BlockStyle merged = mergeBlockStyles(currentTextBlock->getBlockStyle(), blockStyle);
+      currentTextBlock->setBlockStyle(merged);
       return;
     }
 
@@ -244,7 +282,7 @@ void XMLCALL ChapterHtmlSlimParser::startElement(void* userData, const XML_Char*
     }
 
     self->currentBlockStyle = cssStyle;
-    self->startNewTextBlock(alignment, createBlockStyleFromCss(cssStyle));
+    self->startNewTextBlock(alignment, createBlockStyleFromCss(cssStyle, self->renderer.getLineHeight(self->fontId)));
     self->boldUntilDepth = std::min(self->boldUntilDepth, self->depth);
     self->updateEffectiveInlineStyle();
   } else if (matches(name, BLOCK_TAGS, NUM_BLOCK_TAGS)) {
@@ -277,7 +315,7 @@ void XMLCALL ChapterHtmlSlimParser::startElement(void* userData, const XML_Char*
       }
 
       self->currentBlockStyle = cssStyle;
-      self->startNewTextBlock(alignment, createBlockStyleFromCss(cssStyle));
+      self->startNewTextBlock(alignment, createBlockStyleFromCss(cssStyle, self->renderer.getLineHeight(self->fontId)));
       self->updateEffectiveInlineStyle();
 
       if (strcmp(name, "li") == 0) {