[storage] New attempt to save cursor position

apps/code/editor_controller.cpp

@@ -65,13 +65,19 @@ void EditorController::viewWillAppear() {
   ViewController::viewWillAppear();
   m_editorView.loadSyntaxHighlighter();
   if(GlobalPreferences::sharedGlobalPreferences()->cursorSaving()) {
-    m_editorView.setCursorLocation(m_editorView.text() + strlen(m_editorView.text()));
+    int offset = m_script.cursorOffset();
+    if (offset != -1) {
+      m_editorView.setCursorLocation(m_editorView.text() + offset);
+    } else {
+      m_editorView.setCursorLocation(m_editorView.text() + strlen(m_editorView.text()));
+    }
   } else {
     m_editorView.setCursorLocation(m_editorView.text() + strlen(m_editorView.text()));
   }
 }
 
 void EditorController::viewDidDisappear() {
+  m_script.setCursorOffset(m_editorView.cursorLocation() - m_script.content());
   m_editorView.resetSelection();
   m_menuController->scriptContentEditionDidFinish();
 }

apps/code/script.cpp

@@ -65,6 +65,21 @@ bool Script::nameCompliant(const char * name) {
   return false;
 }
 
+uint16_t Script::cursorOffset() {
+  assert(!isNull());
+  Ion::Storage::Metadata metadata = Ion::Storage::sharedStorage()->metadataForRecord(*this);
+  if (metadata.buffer != nullptr) {
+    assert(metadata.size == 2);
+    return *((uint16_t*) metadata.buffer);
+  }
+
+  return -1;
+}
+void Script::setCursorOffset(uint16_t position) {
+  assert(!isNull());
+  Ion::Storage::sharedStorage()->setMetadataForRecord(*this, { &position, sizeof(uint16_t) });
+}
+
 uint8_t * StatusFromData(Script::Data d) {
   return const_cast<uint8_t *>(static_cast<const uint8_t *>(d.buffer));
 }

apps/code/script.h

@@ -50,6 +50,8 @@ public:
   void toggleAutoimportationStatus();
   const char * content() const;
   size_t contentSize() { return value().size - k_statusSize; }
+  void setCursorOffset(uint16_t position); // -1 if no metadata
+  uint16_t cursorOffset();
 
   /* Fetched status */
   bool fetchedFromConsole() const;

ion/include/ion/internal_storage.h

@@ -14,6 +14,11 @@ namespace Ion {
 
 class StorageDelegate;
 
+/**
+ * Purpose the two storage classes :
+ *  - The first (InternalStorage) is the base, it allows to create, modify and delete records
+ *  - The second (Storage) is the visible part. It handle the trash system and the metadata records
+ */
 class InternalStorage {
 public:
   typedef uint16_t record_size_t;
@@ -114,6 +119,7 @@ public:
   // Used by Python OS module
   int numberOfRecords();
   Record recordAtIndex(int index);
+
 protected:
   InternalStorage();
   /* Getters on address in buffer */

ion/include/ion/storage.h

@@ -37,9 +37,16 @@ public:
   Record recordAtIndex(int index);
   void destroyRecord(Record record);
 
+  // Trash
   void reinsertTrash(const char * extension);
   void emptyTrash();
 
+  // Metadata
+  typedef Record::Data Metadata;
+  Metadata metadataForRecord(Record record);
+  Record::ErrorStatus setMetadataForRecord(Record record, Metadata metadata);
+  void removeMetadataForRecord(Record record);
+
 private:
   Storage():
     InternalStorage() {}

ion/include/ion/unicode/utf8_helper.h

@@ -26,6 +26,10 @@ int CountOccurrences(const char * s, CodePoint c);
  * null terminating char otherwise. */
 const char * CodePointSearch(const char * s, CodePoint c, const char * stoppingPosition = nullptr);
 
+/* Returns the last occurrence of a code point in a string, the position of the
+ * null terminating char otherwise. */
+const char * LastCodePoint(const char * s, CodePoint c, const char * stoppingPosition = nullptr);
+
 // Returns true if the text had the code point
 bool HasCodePoint(const char * s, CodePoint c, const char * stoppingPosition = nullptr);
 

ion/src/shared/internal_storage.cpp

@@ -55,7 +55,7 @@ InternalStorage::Record::Record(const char * fullName) {
     m_fullNameCRC32 = 0;
     return;
   }
-  const char * dotChar = UTF8Helper::CodePointSearch(fullName, k_dotChar);
+  const char * dotChar = UTF8Helper::LastCodePoint(fullName, k_dotChar);
   // If no extension, return empty record
   if (*dotChar == 0 || *(dotChar+1) == 0) {
     m_fullNameCRC32 = 0;

ion/src/shared/storage.cpp

@@ -61,6 +61,10 @@ bool Storage::hasRecord(Record r) {
 
 void Storage::destroyRecord(Record record) {
   emptyTrash();
+  const Record metadataRecord = recordBaseNamedWithExtension(record.fullName(), "sys");
+  if (!metadataRecord.isNull()) {
+    InternalStorage::destroyRecord(metadataRecord);
+  }
   m_trashRecord = record;
 }
 
@@ -177,4 +181,21 @@ void Storage::emptyTrash() {
   }
 }
 
+Storage::Metadata Storage::metadataForRecord(Record record) {
+  return recordBaseNamedWithExtension(record.fullName(), "sys").value();
+}
+
+Storage::Record::ErrorStatus Storage::setMetadataForRecord(Record record, Metadata data) {
+  Record metadataRecord = Record(record.fullName(), "sys");
+  if (!hasRecord(metadataRecord)) {
+    return createRecordWithExtension(record.fullName(), "sys", data.buffer, data.size);
+  } else {
+    return metadataRecord.setValue(data);
+  }
+}
+
+void Storage::removeMetadataForRecord(Record record) {
+  recordBaseNamedWithExtension(record.fullName(), "sys").destroy();
+}
+
 }

ion/src/shared/unicode/utf8_helper.cpp

@@ -54,6 +54,34 @@ const char * CodePointSearch(const char * s, CodePoint c, const char * stoppingP
   return currentPointer;
 }
 
+const char * LastCodePoint(const char * s, CodePoint c, const char * stoppingPosition) {
+  if (UTF8Decoder::CharSizeOfCodePoint(c) == 1) {
+    const char * result = nullptr;
+    const char * position = s;
+    while (*position != 0 && (stoppingPosition == nullptr || position != stoppingPosition)) {
+      if (*position == c) {
+        result = position;
+      }
+      position++;
+    }
+    return result ? result : position;
+  }
+  UTF8Decoder decoder(s);
+  const char * currentPointer = s;
+  const char * result = nullptr;
+  CodePoint codePoint = decoder.nextCodePoint();
+  const char * nextPointer = decoder.stringPosition();
+  while (codePoint != UCodePointNull && (stoppingPosition == nullptr || currentPointer < stoppingPosition)) {
+    if (c == codePoint) {
+      result = currentPointer;
+    }
+    currentPointer = nextPointer;
+    codePoint = decoder.nextCodePoint();
+    nextPointer = decoder.stringPosition();
+  }
+  return result ? result : currentPointer;
+}
+
 bool HasCodePoint(const char * s, CodePoint c, const char * stoppingPosition) {
   assert(c != 0);
   const char * resultPosition = CodePointSearch(s, c, stoppingPosition);