From 9e346566946b488aad3c7d372c24ef076b2e81a7 Mon Sep 17 00:00:00 2001
From: David Capello <david@igara.com>
Date: Mon, 9 Jan 2023 15:47:00 -0300
Subject: [PATCH] Fix saving the properties maps when there is an empty map

The exact number of maps specified in the header of the properties
chunk must be saved in the chunk data.
---
 src/app/file/ase_format.cpp | 26 ++++++++++++++++----------
 src/doc/user_data.h         |  8 ++++++++
 2 files changed, 24 insertions(+), 10 deletions(-)

diff --git a/src/app/file/ase_format.cpp b/src/app/file/ase_format.cpp
index 4b2f7c43e..ac66fb8ae 100644
--- a/src/app/file/ase_format.cpp
+++ b/src/app/file/ase_format.cpp
@@ -208,8 +208,9 @@ static void ase_file_write_tileset_chunk(FILE* f, FileOp* fop,
 static void ase_file_write_properties(FILE* f,
                                       const UserData::Properties& properties);
 static void ase_file_write_properties_maps(FILE* f, FileOp* fop,
-                                      const dio::AsepriteExternalFiles& ext_files,
-                                      const doc::UserData::PropertiesMaps& propertiesMaps);
+                                           const dio::AsepriteExternalFiles& ext_files,
+                                            size_t nmaps,
+                                           const doc::UserData::PropertiesMaps& propertiesMaps);
 static bool ase_has_groups(LayerGroup* group);
 static void ase_ungroup_all(LayerGroup* group);
 
@@ -1163,12 +1164,13 @@ static void ase_file_write_user_data_chunk(FILE* f, FileOp* fop,
 {
   ChunkWriter chunk(f, frame_header, ASE_FILE_CHUNK_USER_DATA);
 
+  size_t nmaps = userData->countNonEmptyPropertiesMaps();
   int flags = 0;
   if (!userData->text().empty())
     flags |= ASE_USER_DATA_FLAG_HAS_TEXT;
   if (doc::rgba_geta(userData->color()))
     flags |= ASE_USER_DATA_FLAG_HAS_COLOR;
-  if (!userData->propertiesMaps().empty())
+  if (nmaps)
     flags |= ASE_USER_DATA_FLAG_HAS_PROPERTIES;
   fputl(flags, f);
 
@@ -1183,7 +1185,7 @@ static void ase_file_write_user_data_chunk(FILE* f, FileOp* fop,
   }
 
   if (flags & ASE_USER_DATA_FLAG_HAS_PROPERTIES) {
-    ase_file_write_properties_maps(f, fop, ext_files, userData->propertiesMaps());
+    ase_file_write_properties_maps(f, fop, ext_files, nmaps, userData->propertiesMaps());
   }
 }
 
@@ -1527,11 +1529,11 @@ static void ase_file_write_properties(FILE* f,
 }
 
 static void ase_file_write_properties_maps(FILE* f, FileOp* fop,
-                                      const dio::AsepriteExternalFiles& ext_files,
-                                      const doc::UserData::PropertiesMaps& propertiesMaps)
+                                           const dio::AsepriteExternalFiles& ext_files,
+                                           size_t nmaps,
+                                           const doc::UserData::PropertiesMaps& propertiesMaps)
 {
-  uint32_t numMaps = propertiesMaps.size();
-  if (numMaps == 0) return;
+  ASSERT(nmaps > 0);
 
   long startPos = ftell(f);
   // We zero the size in bytes of all properties maps stored in this
@@ -1539,7 +1541,7 @@ static void ase_file_write_properties_maps(FILE* f, FileOp* fop,
   // of all properties maps, at which point this field is overwritten)
   fputl(0, f);
 
-  fputl(numMaps, f);
+  fputl(nmaps, f);
   for (auto propertiesMap : propertiesMaps) {
     const UserData::Properties& properties = propertiesMap.second;
     // Skip properties map if it doesn't have any property
@@ -1558,7 +1560,11 @@ static void ase_file_write_properties_maps(FILE* f, FileOp* fop,
       // didn't support it previously.
       ASSERT(false);
       fop->setError("Error writing properties for extension '%s'.\n", extensionKey.c_str());
-      continue;
+
+      // We have to write something for this extensionId, because we
+      // wrote the number of expected property maps (nmaps) in the
+      // header.
+      //continue;
     }
     fputl(extensionId, f);
     ase_file_write_properties(f, properties);
diff --git a/src/doc/user_data.h b/src/doc/user_data.h
index 60666435c..e97dbfff4 100644
--- a/src/doc/user_data.h
+++ b/src/doc/user_data.h
@@ -109,6 +109,14 @@ namespace doc {
     Properties& properties() { return properties(std::string()); }
     Properties& properties(const std::string& groupKey) { return m_propertiesMaps[groupKey]; }
 
+    size_t countNonEmptyPropertiesMaps() const {
+      size_t i = 0;
+      for (const auto& it : m_propertiesMaps)
+        if (!it.second.empty())
+          ++i;
+      return i;
+    }
+
     void setText(const std::string& text) { m_text = text; }
     void setColor(color_t color) { m_color = color; }