generateExtension static method

Implementation

static String generateExtension(
    final StringBuffer classBuffer,
    final ClassElement aClass,
    final bool hasFSSupport,
    final bool hasRDBSupport
    ) {
  classBuffer.writeln("// - - - - - - - FirestormObject ${aClass.name} - - - - - - -");
  classBuffer.writeln();

  //Generate extension class
  classBuffer.writeln("extension ${aClass.name}Model on ${aClass.name} {");

  classBuffer.writeln();

  //Generate static fields for Firestore & RDB support
  if (hasFSSupport) {
    classBuffer.writeln("\tstatic final bool fsSupport = true;");
  }
  else {
    classBuffer.writeln("\tstatic final bool fsSupport = false;");
  }

  if (hasRDBSupport) {
    classBuffer.writeln("\tstatic final bool rdbSupport = true;");
  }
  else {
    classBuffer.writeln("\tstatic final bool rdbSupport = false;");
  }
  classBuffer.writeln();

  //Generate toMap() method
  classBuffer.writeln("\t Map<String, dynamic> toMap() {");
  classBuffer.writeln("\t\t return {");

  ConstructorElement constructorElement = aClass.unnamedConstructor!;
  List<ParameterElement> params = constructorElement.parameters;

  //Fields:
  for (ParameterElement param in params) {
    FieldElement? matchingField = aClass.getField(param.displayName); //match to field

    for (final parent in aClass.allSupertypes) { //Find field in parent classes
      for (final parentField in parent.element.fields) {
        if (parentField.name != "hashCode" &&
            parentField.name == param.name &&
            parentField.name != "runtimeType") {
          matchingField = parentField; //set matching field to parent field
          break;
        }
      }
    }

    if (matchingField == null) {
      throw InvalidClassException(aClass.name);
    }

    if (matchingField.metadata.any((m) => m.element?.displayName == 'Exclude')) {
      if (matchingField.type.nullabilitySuffix == NullabilitySuffix.question) {
        //Do nothing, this is kept for reference.
        // classBuffer.writeln("\t\t\t '${param.name}': null,"); //set excluded to null
      }
      else {
        throw InvalidClassException(aClass.name); //cannot have excluded without nullable
      }
    }
    else {
      //If this is a user-defined type, expand it using it own toMap():
      if (!matchingField.type.element!.library!.isDartCore && matchingField.type is InterfaceType && !ClassChecker.isEnumType(matchingField.type)) {
        classBuffer.writeln("\t\t\t '${param.name}': this.${param.name}.toMap(),"); //call toMap() on user-defined type
      }
      //enum:
      else if (ClassChecker.isEnumType(matchingField.type)) {
        classBuffer.writeln("\t\t\t '${param.name}': this.${param.name}.toString(),"); //not excluded (normal, enum)
      }
      //other:
      else {
        //Otherwise, just use the attribute:
        classBuffer.writeln("\t\t\t '${param.name}': this.${param.name},"); //not excluded (normal)
      }
    }
  }

  classBuffer.writeln("\t\t };");
  classBuffer.writeln("\t }");
  classBuffer.writeln();

  //Generate fromMap() method
  classBuffer.writeln("\tstatic ${aClass.name} fromMap(Map<String, dynamic> map) {");
  classBuffer.writeln("\t\t return ${aClass.name}(");

  //Constructor parameters:
  for (ParameterElement param in params) {

    FieldElement? matchingField = aClass.getField(param.displayName); //match to field

    for (final parent in aClass.allSupertypes) { //Find field in parent classes
      for (final parentField in parent.element.fields) {
        if (parentField.name != "hashCode" &&
            parentField.name == param.name &&
            parentField.name != "runtimeType") {
          matchingField = parentField; //set matching field to parent field
          break;
        }
      }
    }

    if (matchingField == null) {
      throw InvalidClassException(aClass.name);
    }

    if (matchingField.metadata.any((m) => m.element?.displayName == 'Exclude')) {
      if (matchingField.type.nullabilitySuffix == NullabilitySuffix.question) {
        classBuffer.writeln("\t\t\t null,"); //set excluded to null
      }
      else {
        throw InvalidClassException(aClass.name); //cannot have excluded without nullable
      }
    }
    else {
      //If this is a user-defined type, use its own fromMap():
      if (!matchingField.type.element!.library!.isDartCore && matchingField.type is InterfaceType && !ClassChecker.isEnumType(matchingField.type)) {
        classBuffer.writeln("\t\t\t ${matchingField.type.getDisplayString()}Model.fromMap(Map<String, dynamic>.from(map['${param.name}'] as Map)),"); //call fromMap() on user-defined type
      }
      else {
        if (param.type.isDartCoreList) {
          final listType = param.type as InterfaceType;
          DartType elementType = listType.typeArguments[0];
          classBuffer.writeln("\t\t\t map['${param.name}'] != null ? map['${param.name}'].cast<${elementType.getDisplayString()}>() : [],"); //cast to List<elementType>
        }
        else if (param.type.isDartCoreMap) {
          final listType = param.type as InterfaceType;
          DartType valueType = listType.typeArguments[1];
          classBuffer.writeln("\t\t\t map['${param.name}'] != null ? map['${param.name}'].cast<String, ${valueType.getDisplayString()}>() : {},"); //cast to Map<String, valueType>
        }
        else if (ClassChecker.isEnumType(param.type)) {
          classBuffer.writeln("\t\t\t ${param.type.getDisplayString()}.values.firstWhere((e) => e.toString() == map['${param.name}'] as String),"); //(normal, enum)
        }
        else {
          classBuffer.writeln("\t\t\t map['${param.name}'] as ${matchingField.type.getDisplayString()},"); //not excluded (normal)
        }
      }
    }
  }

  classBuffer.writeln("\t\t );");
  classBuffer.writeln("\t }");
  classBuffer.writeln();

  //End extension class
  classBuffer.writeln("}");
  classBuffer.writeln();

  return classBuffer.toString();
}