From 1e59aa6d5d3009e626cd4ee997975e41e72ea652 Mon Sep 17 00:00:00 2001
From: Jonas Diemer <jonasdiemer@gmail.com>
Date: Mon, 29 Dec 2025 14:51:33 +0100
Subject: [PATCH] Added logic to parse the guide section of the Content Opf.

---
 lib/Epub/Epub/parsers/ContentOpfParser.cpp | 41 ++++++++++++++++++++++
 lib/Epub/Epub/parsers/ContentOpfParser.h   |  1 +
 2 files changed, 42 insertions(+)

diff --git a/lib/Epub/Epub/parsers/ContentOpfParser.cpp b/lib/Epub/Epub/parsers/ContentOpfParser.cpp
index a62b2d0a..85604d2e 100644
--- a/lib/Epub/Epub/parsers/ContentOpfParser.cpp
+++ b/lib/Epub/Epub/parsers/ContentOpfParser.cpp
@@ -122,6 +122,18 @@ void XMLCALL ContentOpfParser::startElement(void* userData, const XML_Char* name
     return;
   }
 
+  if (self->state == IN_PACKAGE && (strcmp(name, "guide") == 0 || strcmp(name, "opf:guide") == 0)) {
+    self->state = IN_GUIDE;
+    // TODO Remove print
+    Serial.printf("[%lu] [COF] Entering guide state.\n", millis());
+    if (!FsHelpers::openFileForRead("COF", self->cachePath + itemCacheFile, self->tempItemStore)) {
+      Serial.printf(
+          "[%lu] [COF] Couldn't open temp items file for reading. This is probably going to be a fatal error.\n",
+          millis());
+    }
+    return;
+  }
+
   if (self->state == IN_METADATA && (strcmp(name, "meta") == 0 || strcmp(name, "opf:meta") == 0)) {
     bool isCover = false;
     std::string coverItemId;
@@ -200,6 +212,29 @@ void XMLCALL ContentOpfParser::startElement(void* userData, const XML_Char* name
       return;
     }
   }
+  // parse the guide
+  if (self->state == IN_GUIDE && (strcmp(name, "reference") == 0 || strcmp(name, "opf:reference") == 0)) {
+    std::string type;
+    std::string textHref;
+    for (int i = 0; atts[i]; i += 2) {
+      if (strcmp(atts[i], "type") == 0) {
+        type = atts[i + 1];
+        if (type == "text") {
+          continue;
+        } else {
+          Serial.printf("[%lu] [COF] Skipping non-text reference in guide: %s\n", millis(), type.c_str());
+          break;
+        }
+      } else if (strcmp(atts[i], "href") == 0) {
+        textHref = atts[i + 1];
+      }
+    }
+    if ((type == "text") && (textHref.length() > 0)) {
+      Serial.printf("[%lu] [COF] Found text reference in guide: %s.\n", millis(), textHref.c_str());
+      // TODO: now this has to become the chapter we display
+    }
+    return;
+  }
 }
 
 void XMLCALL ContentOpfParser::characterData(void* userData, const XML_Char* s, const int len) {
@@ -221,6 +256,12 @@ void XMLCALL ContentOpfParser::endElement(void* userData, const XML_Char* name)
     return;
   }
 
+  if (self->state == IN_GUIDE && (strcmp(name, "guide") == 0 || strcmp(name, "opf:guide") == 0)) {
+    self->state = IN_PACKAGE;
+    self->tempItemStore.close();
+    return;
+  }
+
   if (self->state == IN_MANIFEST && (strcmp(name, "manifest") == 0 || strcmp(name, "opf:manifest") == 0)) {
     self->state = IN_PACKAGE;
     self->tempItemStore.close();
diff --git a/lib/Epub/Epub/parsers/ContentOpfParser.h b/lib/Epub/Epub/parsers/ContentOpfParser.h
index 5415de67..252ebee1 100644
--- a/lib/Epub/Epub/parsers/ContentOpfParser.h
+++ b/lib/Epub/Epub/parsers/ContentOpfParser.h
@@ -14,6 +14,7 @@ class ContentOpfParser final : public Print {
     IN_BOOK_TITLE,
     IN_MANIFEST,
     IN_SPINE,
+    IN_GUIDE,
   };
 
   const std::string& cachePath;