Public release

2025-12-03 22:06:45 +11:00
commit 2ccdbeecc8
54 changed files with 33356 additions and 0 deletions
@@ -0,0 +1,181 @@
+#include "EpubHtmlParser.h"
+
+#include <EpdRenderer.h>
+#include <HardwareSerial.h>
+
+#include "Page.h"
+#include "htmlEntities.h"
+
+const char* HEADER_TAGS[] = {"h1", "h2", "h3", "h4", "h5", "h6"};
+constexpr int NUM_HEADER_TAGS = sizeof(HEADER_TAGS) / sizeof(HEADER_TAGS[0]);
+
+const char* BLOCK_TAGS[] = {"p", "li", "div", "br"};
+constexpr int NUM_BLOCK_TAGS = sizeof(BLOCK_TAGS) / sizeof(BLOCK_TAGS[0]);
+
+const char* BOLD_TAGS[] = {"b"};
+constexpr int NUM_BOLD_TAGS = sizeof(BOLD_TAGS) / sizeof(BOLD_TAGS[0]);
+
+const char* ITALIC_TAGS[] = {"i"};
+constexpr int NUM_ITALIC_TAGS = sizeof(ITALIC_TAGS) / sizeof(ITALIC_TAGS[0]);
+
+const char* IMAGE_TAGS[] = {"img"};
+constexpr int NUM_IMAGE_TAGS = sizeof(IMAGE_TAGS) / sizeof(IMAGE_TAGS[0]);
+
+const char* SKIP_TAGS[] = {"head", "table"};
+constexpr int NUM_SKIP_TAGS = sizeof(SKIP_TAGS) / sizeof(SKIP_TAGS[0]);
+
+// given the start and end of a tag, check to see if it matches a known tag
+bool matches(const char* tag_name, const char* possible_tags[], const int possible_tag_count) {
+  for (int i = 0; i < possible_tag_count; i++) {
+    if (strcmp(tag_name, possible_tags[i]) == 0) {
+      return true;
+    }
+  }
+  return false;
+}
+
+// start a new text block if needed
+void EpubHtmlParser::startNewTextBlock(const BLOCK_STYLE style) {
+  if (currentTextBlock) {
+    // already have a text block running and it is empty - just reuse it
+    if (currentTextBlock->isEmpty()) {
+      currentTextBlock->set_style(style);
+      return;
+    }
+
+    currentTextBlock->finish();
+    makePages();
+    delete currentTextBlock;
+  }
+  currentTextBlock = new TextBlock(style);
+}
+
+bool EpubHtmlParser::VisitEnter(const tinyxml2::XMLElement& element, const tinyxml2::XMLAttribute* firstAttribute) {
+  const char* tag_name = element.Name();
+  if (matches(tag_name, IMAGE_TAGS, NUM_IMAGE_TAGS)) {
+    const char* src = element.Attribute("src");
+    if (src) {
+      // don't leave an empty text block in the list
+      // const BLOCK_STYLE style = currentTextBlock->get_style();
+      if (currentTextBlock->isEmpty()) {
+        delete currentTextBlock;
+        currentTextBlock = nullptr;
+      }
+      // TODO: Fix this
+      // blocks.push_back(new ImageBlock(m_base_path + src));
+      // start a new text block - with the same style as before
+      // startNewTextBlock(style);
+    } else {
+      // ESP_LOGE(TAG, "Could not find src attribute");
+    }
+    return false;
+  }
+
+  if (matches(tag_name, SKIP_TAGS, NUM_SKIP_TAGS)) {
+    return false;
+  }
+
+  // Serial.printf("Text: %s\n", element.GetText());
+
+  if (matches(tag_name, HEADER_TAGS, NUM_HEADER_TAGS)) {
+    insideBoldTag = true;
+    startNewTextBlock(CENTER_ALIGN);
+  } else if (matches(tag_name, BLOCK_TAGS, NUM_BLOCK_TAGS)) {
+    if (strcmp(tag_name, "br") == 0) {
+      startNewTextBlock(currentTextBlock->get_style());
+    } else {
+      startNewTextBlock(JUSTIFIED);
+    }
+  } else if (matches(tag_name, BOLD_TAGS, NUM_BOLD_TAGS)) {
+    insideBoldTag = true;
+  } else if (matches(tag_name, ITALIC_TAGS, NUM_ITALIC_TAGS)) {
+    insideItalicTag = true;
+  }
+  return true;
+}
+/// Visit a text node.
+bool EpubHtmlParser::Visit(const tinyxml2::XMLText& text) {
+  const char* content = text.Value();
+  currentTextBlock->addSpan(replaceHtmlEntities(content), insideBoldTag, insideItalicTag);
+  return true;
+}
+
+bool EpubHtmlParser::VisitExit(const tinyxml2::XMLElement& element) {
+  const char* tag_name = element.Name();
+  if (matches(tag_name, HEADER_TAGS, NUM_HEADER_TAGS)) {
+    insideBoldTag = false;
+  } else if (matches(tag_name, BLOCK_TAGS, NUM_BLOCK_TAGS)) {
+    // nothing to do
+  } else if (matches(tag_name, BOLD_TAGS, NUM_BOLD_TAGS)) {
+    insideBoldTag = false;
+  } else if (matches(tag_name, ITALIC_TAGS, NUM_ITALIC_TAGS)) {
+    insideItalicTag = false;
+  }
+  return true;
+}
+
+bool EpubHtmlParser::parseAndBuildPages() {
+  startNewTextBlock(JUSTIFIED);
+  tinyxml2::XMLDocument doc(false, tinyxml2::COLLAPSE_WHITESPACE);
+
+  const tinyxml2::XMLError result = doc.LoadFile(filepath);
+  if (result != tinyxml2::XML_SUCCESS) {
+    Serial.printf("Failed to load file, Error: %s\n", tinyxml2::XMLDocument::ErrorIDToName(result));
+    return false;
+  }
+
+  doc.Accept(this);
+  if (currentTextBlock) {
+    makePages();
+    completePageFn(currentPage);
+    currentPage = nullptr;
+    delete currentTextBlock;
+    currentTextBlock = nullptr;
+  }
+
+  return true;
+}
+
+void EpubHtmlParser::makePages() {
+  if (!currentTextBlock) {
+    Serial.println("!! No text block to make pages for !!");
+    return;
+  }
+
+  if (!currentPage) {
+    currentPage = new Page();
+  }
+
+  const int lineHeight = renderer->getLineHeight();
+  const int pageHeight = renderer->getPageHeight();
+
+  // Long running task, make sure to let other things happen
+  vTaskDelay(1);
+
+  if (currentTextBlock->getType() == TEXT_BLOCK) {
+    const auto lines = currentTextBlock->splitIntoLines(renderer);
+
+    for (const auto line : lines) {
+      if (currentPage->nextY + lineHeight > pageHeight) {
+        completePageFn(currentPage);
+        currentPage = new Page();
+      }
+
+      currentPage->elements.push_back(new PageLine(line, currentPage->nextY));
+      currentPage->nextY += lineHeight;
+    }
+    // TODO: Fix spacing between paras
+    // add some extra line between blocks
+    currentPage->nextY += lineHeight / 2;
+  }
+  // TODO: Image block support
+  // if (block->getType() == BlockType::IMAGE_BLOCK) {
+  //   ImageBlock *imageBlock = (ImageBlock *)block;
+  //   if (y + imageBlock->height > page_height) {
+  //     pages.push_back(new Page());
+  //     y = 0;
+  //   }
+  //   pages.back()->elements.push_back(new PageImage(imageBlock, y));
+  //   y += imageBlock->height;
+  // }
+}