add blueprint & property implementation

Signed-off-by: Folling <mail@folling.io>

include/ikarus/objects/blueprint.h

@@ -154,6 +154,22 @@ IKA_API void ikarus_blueprint_set_name(
 	struct IkarusErrorData * error_out
 );
 
+/// \brief Gets whether a blueprint has a property.
+/// \param blueprint The blueprint to check the property of.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
+/// \param property The property to check the existence of.
+/// \pre \li Must not be null.
+///	\pre \li Must exist.
+///	\pre \li Must be in the same project as the blueprint.
+///	\param error_out \see errors.h
+///	\return True if the blueprint has the property, false otherwise or if an error occurs.
+IKA_API bool ikarus_blueprint_has_property(
+	struct IkarusBlueprint * blueprint,
+	struct IkarusProperty * property,
+	struct IkarusErrorData * error_out
+);
+
 /// \brief Gets the properties of a blueprint.
 /// \param blueprint The blueprint to get the properties of.
 /// \pre \li Must not be null.
@@ -161,7 +177,7 @@ IKA_API void ikarus_blueprint_set_name(
 /// \param size_out An out parameter for the number of items in the returned array or undefined if an error occurs.
 /// \param error_out \see errors.h
 /// \return The properties of the blueprint or null if an error occurs.
-IKA_API struct IkarusBlueprint ** ikarus_blueprint_get_properties(
+IKA_API struct IkarusProperty ** ikarus_blueprint_get_properties(
 	struct IkarusBlueprint * blueprint,
 	size_t * size_out,
 	struct IkarusErrorData * error_out
@@ -176,15 +192,15 @@ IKA_API struct IkarusBlueprint ** ikarus_blueprint_get_properties(
 IKA_API size_t
 ikarus_blueprint_get_properties_count(struct IkarusBlueprint * blueprint, struct IkarusErrorData * error_out);
 
-/// \brief Gets all entities linked to a blueprint.
+/// \brief Gets the linked entities of a blueprint.
-/// \param blueprint The blueprint to get the entities of.
+/// \param blueprint The blueprint to get the linked entities of.
 /// \pre \li Must not be null.
 /// \pre \li Must exist.
 /// \param size_out An out parameter for the number of items in the returned array or undefined if an error occurs.
 /// \remark Ignore if null.
 /// \param error_out \see errors.h
-/// \return The entities linked to the blueprint or null if an error occurs.
+/// \return The linked entities of the blueprint or null if an error occurs.
-IKA_API struct IkarusEntity ** ikarus_blueprint_get_entities(
+IKA_API struct IkarusEntity ** ikarus_blueprint_get_linked_entities(
 	struct IkarusBlueprint * blueprint,
 	size_t * size_out,
 	struct IkarusErrorData * error_out
@@ -197,7 +213,7 @@ IKA_API struct IkarusEntity ** ikarus_blueprint_get_entities(
 /// \param error_out \see errors.h
 /// \return The number of entities linked to the blueprint or 0 if an error occurs.
 IKA_API size_t
-ikarus_blueprint_get_entities_count(struct IkarusBlueprint * blueprint, struct IkarusErrorData * error_out);
+ikarus_blueprint_get_linked_entities_count(struct IkarusBlueprint * blueprint, struct IkarusErrorData * error_out);
 
 IKARUS_END_HEADER
 

include/ikarus/objects/property.h

@@ -53,23 +53,47 @@ enum IkarusPropertyCreateFlags {
 /// \param project The project to create the property in.
 /// \pre \li Must not be null.
 /// \pre \li Must exist.
+/// \param blueprint The blueprint to create the property for.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
 /// \param name The name of the property.
 /// \pre \li Must not be null.
 /// \pre \li Must not be empty.
 /// \param schema The schema of the property.
 /// \pre \li Must not be null.
+/// \pre \li Must be a valid JSON buffer for a IkarusValueSchema. \see schema.h
+/// \param default_value The default value of the property.
+/// \pre \li Must not be null.
+/// \pre \li Must be a valid JSON buffer for an IkarusValueData. \see data.h
 /// \param flags Flags for creating the property.
 /// \param error_out \see errors.h
 /// \return The created property or NULL if an error occurred.
 /// \remark Must only be deleted with #ikarus_property_delete.
 IKA_API IkarusProperty * ikarus_property_create(
-	struct IkarusProject * project,
+	struct IkarusBlueprint * blueprint,
 	char const * name,
-	struct IkarusValueSchema * schema,
+	char const * schema,
+	char const * default_value,
 	IkarusPropertyCreateFlags flags,
 	IkarusErrorData * error_out
 );
 
+/// \brief Flags for copying a property.
+enum IkarusPropertyCopyFlags {
+	/// \brief No flags.
+	IkarusPropertyCopyFlags_None = 0,
+};
+
+/// \brief Copy a property.
+/// \param property The property to copy.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
+/// \param flags Flags for copying the property.
+/// \param error_out \see errors.h
+/// \return The copied property or NULL if an error occurred.
+IKA_API IkarusProperty *
+ikarus_property_copy(IkarusProperty * property, IkarusPropertyCopyFlags flags, IkarusErrorData * error_out);
+
 /// \brief Flags for deleting a property.
 enum IkarusPropertyDeleteFlags {
 	/// \brief No flags.
@@ -101,15 +125,6 @@ IKA_API struct IkarusProject * ikarus_property_get_project(IkarusProperty * prop
 /// \remark Ownership remains with libikarus.
 IKA_API char const * ikarus_property_get_name(IkarusProperty * property, IkarusErrorData * error_out);
 
-/// \brief Get the schema of a property.
-/// \param property The property to get the schema of.
-/// \pre \li Must not be null.
-/// \pre \li Must exist.
-/// \param error_out \see errors.h
-/// \return The schema of the property or null if an error occurred.
-/// \remark Ownership remains with libikarus.
-IKA_API struct IkarusValueSchema * ikarus_property_get_schema(IkarusProperty * property, IkarusErrorData * error_out);
-
 /// \brief Flags for setting the name of a property.
 enum IkarusPropertySetNameFlags {
 	/// \brief No flags.
@@ -133,6 +148,78 @@ IKA_API void ikarus_property_set_name(
 	IkarusErrorData * error_out
 );
 
+/// \brief Get the schema of a property.
+/// \param property The property to get the schema of.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
+/// \param error_out \see errors.h
+/// \return The schema of the property in JSON format or null if an error occurred. \see schema.h
+IKA_API char const * ikarus_property_get_schema(IkarusProperty * property, IkarusErrorData * error_out);
+
+/// \brief Flags for setting the schema of a property.
+enum IkarusPropertySetSchemaFlags {
+	/// \brief No flags.
+	IkarusPropertySetSchemaFlags_None = 0,
+};
+
+/// \brief Set the schema of a property.
+/// \details Setting the schema of a property will reset all existing values.
+/// \param property The property to set the schema of.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
+/// \param schema The new schema of the property.
+/// \pre \li Must not be null.
+/// \pre \li Must be a valid JSON buffer for a IkarusValueSchema. \see schema.h
+/// \param new_default_value The new default value of the property.
+/// \pre \li Must not be null.
+/// \pre \li Must be a valid JSON buffer for an IkarusValueData. \see data.h
+/// \param flags Flags for setting the schema of the property.
+/// \param error_out \see errors.h
+IKA_API void ikarus_property_set_schema(
+	IkarusProperty * property,
+	char const * schema,
+	char const * new_default_value,
+	IkarusPropertySetSchemaFlags flags,
+	IkarusErrorData * error_out
+);
+
+/// \brief Get the default value of a property.
+/// \param property The property to get the default value of.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
+/// \param error_out \see errors.h
+/// \return The default value data of the property in JSON format or null if an error occurred. \see data.h
+IKA_API char const * ikarus_property_get_default_value(IkarusProperty * property, IkarusErrorData * error_out);
+
+/// \details The default value must match the schema of the property.
+
+/// \brief Flags for setting the default value of a property.
+enum IkarusPropertySetDefaultValueFlags {
+	/// \brief No flags.
+	IkarusPropertySetDefaultValueFlags_None = 0,
+};
+
+/// \brief Flags for setting the default value of a property.
+/// \param property The property to set the default value of.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
+/// \param value The new default value of the property.
+/// \pre \li Must not be null.
+/// \pre \li Must be valid JSON \see data.h
+/// \pre \li Must be valid according to the property's schema.
+/// \param flags Flags for setting the default value of the property.
+/// \param error_out \see errors.h
+IKA_API void ikarus_property_set_default_value(
+	IkarusProperty * property,
+	char const * value,
+	IkarusPropertySetDefaultValueFlags flags,
+	IkarusErrorData * error_out
+);
+
+/// \brief Gets all values for a property.
+/// \param property The property to get the values of.
+///
+
 IKARUS_END_HEADER
 
 /// @}

src/ikarus/objects/blueprint.cpp

@@ -3,12 +3,27 @@
 #include <ikarus/errors.hpp>
 #include <ikarus/objects/blueprint.hpp>
 #include <ikarus/objects/entity.h>
+#include <ikarus/objects/property.h>
 #include <ikarus/persistence/project.hpp>
 
 IkarusBlueprint::IkarusBlueprint(struct IkarusProject * project, int64_t id):
 	project{project},
 	id{id} {}
 
+bool ikarus_blueprint_exists(IkarusBlueprint * blueprint, IkarusErrorData * error_out) {
+	IKARUS_FAIL_IF_NULL(blueprint, false);
+	IKARUS_VTRYRV_OR_FAIL(
+		auto exists,
+		false,
+		"failed to check whether blueprint exists: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db
+			->query_one<bool>("SELECT EXISTS(SELECT 1 FROM `blueprints` WHERE `id` = ?)", blueprint->id)
+	);
+
+	return exists;
+}
+
 IkarusBlueprint * ikarus_blueprint_create(
 	struct IkarusProject * project,
 	char const * name,
@@ -35,17 +50,14 @@ IkarusBlueprint * ikarus_blueprint_create_from_entity(
 	IkarusBlueprintCreateFromEntityFlags flags,
 	struct IkarusErrorData * error_out
 ) {
-	IKARUS_TRYRV_OR_FAIL(
-		nullptr,
-		"{}",
-		IkarusErrorInfo_Database_QueryFailed,
-		ikarus_libikarus_func_call_to_result(
-			error_out,
-			ikarus_must_return_true(ikarus_entity_exists, "entity doesn't exist", IkarusErrorInfo_Client_NonExistent),
-			entity
-		)
-	);
 	IKARUS_FAIL_IF_NAME_INVALID(name, nullptr);
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"entity must not be null",
+		IkarusErrorInfo_Client_InvalidInput,
+		ikarus_entity_exists,
+		entity
+	);
 
 	IKARUS_VTRYRV_OR_FAIL(
 		auto id,
@@ -59,15 +71,308 @@ IkarusBlueprint * ikarus_blueprint_create_from_entity(
 
 			CPPBASE_TRY(entity->project->db->execute(
 				"INSERT INTO `properties`(`blueprint`, `name`, `schema`) "
-				"SELECT ?, `name`, json_extract(`value`, '$.schema') FROM `entity_values` "
+				"SELECT ?, `name`, json_extract(`value`, '$.schema') AS `schema` FROM `entity_values` "
 				"WHERE `entity` = ?",
 				id,
 				entity->id
 			))
 
-			return cppbase::ok(entity->project->db->last_insert_rowid());
+			return cppbase::ok(id);
 		})
 	);
 
 	return new IkarusBlueprint{entity->project, id};
 }
+
+struct IkarusBlueprint * ikarus_blueprint_copy(
+	struct IkarusBlueprint * blueprint,
+	IkarusBlueprintCopyFlags flags,
+	struct IkarusErrorData * error_out
+) {
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto id,
+		nullptr,
+		"failed to copy blueprint: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db->transact(
+			[blueprint](auto * db) -> cppbase::Result<int64_t, sqlitecpp::TransactionError> {
+				CPPBASE_TRY(db->execute(
+					"INSERT INTO `blueprints`(`name`) "
+					"SELECT `name` FROM `blueprints` WHERE `id` = ?",
+					blueprint->id
+				));
+
+				auto const id = db->last_insert_rowid();
+
+				CPPBASE_TRY(blueprint->project->db->execute(
+					"INSERT INTO `properties`(`blueprint`, `name`, `schema`) "
+					"SELECT ?, `name`, `schema` FROM `properties` "
+					"WHERE `blueprint` = ?",
+					id,
+					blueprint->id
+				));
+
+				return cppbase::ok(id);
+			}
+		)
+	);
+
+	return new IkarusBlueprint{blueprint->project, id};
+}
+
+void ikarus_blueprint_delete(
+	struct IkarusBlueprint * blueprint,
+	IkarusBlueprintDeleteFlags flags,
+	IkarusErrorData * error_out
+) {
+	IKARUS_ASCERTAIN(
+		IKARUS_VOID_RETURN,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+
+	IKARUS_TRYRV_OR_FAIL(
+		IKARUS_VOID_RETURN,
+		"failed to delete blueprint: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db->execute("DELETE FROM `blueprints` WHERE `id` = ?", blueprint->id)
+	);
+
+	delete blueprint;
+}
+
+struct IkarusProject *
+ikarus_blueprint_get_project(struct IkarusBlueprint * blueprint, struct IkarusErrorData * error_out) {
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+
+	return blueprint->project;
+}
+
+char const * ikarus_blueprint_get_name(struct IkarusBlueprint * blueprint, struct IkarusErrorData * error_out) {
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto name,
+		nullptr,
+		"failed to get name for blueprint: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db->query_one<char const *>("SELECT `name` FROM `blueprints` WHERE `id` = ?", blueprint->id)
+	);
+
+	return name;
+}
+
+void ikarus_blueprint_set_name(
+	struct IkarusBlueprint * blueprint,
+	char const * name,
+	IkarusBlueprintSetNameFlags flags,
+	struct IkarusErrorData * error_out
+) {
+	IKARUS_ASCERTAIN(
+		IKARUS_VOID_RETURN,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+	IKARUS_FAIL_IF_NAME_INVALID(name, IKARUS_VOID_RETURN);
+
+	IKARUS_TRYRV_OR_FAIL(
+		IKARUS_VOID_RETURN,
+		"failed to set name for blueprint: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db->execute("UPDATE `blueprints` SET `name` = ? WHERE `id` = ?", name, blueprint->id)
+	);
+}
+
+bool ikarus_blueprint_has_property(
+	struct IkarusBlueprint * blueprint,
+	struct IkarusProperty * property,
+	struct IkarusErrorData * error_out
+) {
+	IKARUS_ASCERTAIN(
+		false,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+
+	IKARUS_ASCERTAIN(
+		false,
+		"property doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_property_exists,
+		property
+	);
+
+	IKARUS_FAIL_IF(
+		blueprint->project != property->project,
+		false,
+		"property does not belong to blueprint's project",
+		IkarusErrorInfo_Client_NotLinked
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto exists,
+		false,
+		"failed to check if blueprint has property: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db->query_one<bool>(
+			"SELECT EXISTS(SELECT 1 FROM `properties` WHERE `blueprint` = ? AND `id` = ?)",
+			blueprint->id,
+			property->id
+		)
+	);
+
+	return exists;
+}
+
+struct IkarusProperty ** ikarus_blueprint_get_properties(
+	struct IkarusBlueprint * blueprint,
+	size_t * size_out,
+	struct IkarusErrorData * error_out
+) {
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+
+	IKARUS_VCALL(auto count, nullptr, ikarus_blueprint_get_properties_count, blueprint);
+
+	std::int64_t ids[count];
+
+	IKARUS_TRYRV_OR_FAIL(
+		nullptr,
+		"failed to get properties for blueprint: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db->query_many_buffered<std::int64_t>(
+			"SELECT `id` FROM `properties` WHERE `blueprint` = ?",
+			ids,
+			count,
+			blueprint->id
+		)
+	);
+
+	auto properties = new IkarusProperty *[count];
+	std::transform(ids, ids + count, properties, [project = blueprint->project](auto id) {
+		return new IkarusProperty{project, id};
+	});
+
+	if (size_out) {
+		*size_out = count;
+	}
+
+	return properties;
+}
+
+size_t ikarus_blueprint_get_properties_count(struct IkarusBlueprint * blueprint, struct IkarusErrorData * error_out) {
+	IKARUS_ASCERTAIN(
+		0,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto count,
+		0,
+		"failed to get properties count for blueprint: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db
+			->query_one<std::int64_t>("SELECT COUNT(*) FROM `properties` WHERE `blueprint` = ?", blueprint->id)
+	);
+
+	return count;
+}
+
+struct IkarusEntity ** ikarus_blueprint_get_linked_entities(
+	struct IkarusBlueprint * blueprint,
+	size_t * size_out,
+	struct IkarusErrorData * error_out
+) {
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+
+	IKARUS_VCALL(auto count, nullptr, ikarus_blueprint_get_linked_entities_count, blueprint);
+
+	std::int64_t ids[count];
+
+	IKARUS_TRYRV_OR_FAIL(
+		nullptr,
+		"failed to get entities for blueprint: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db->query_many_buffered<std::int64_t>(
+			"SELECT `entity` FROM `entity_blueprint_links` WHERE `blueprint` = ?",
+			ids,
+			count,
+			blueprint->id
+		)
+	);
+
+	auto entities = new IkarusEntity *[count];
+	std::transform(ids, ids + count, entities, [project = blueprint->project](auto id) {
+		return new IkarusEntity{project, id};
+	});
+
+	if (size_out) {
+		*size_out = count;
+	}
+
+	return entities;
+}
+
+size_t
+ikarus_blueprint_get_linked_entities_count(struct IkarusBlueprint * blueprint, struct IkarusErrorData * error_out) {
+	IKARUS_ASCERTAIN(
+		0,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto count,
+		0,
+		"failed to get linked entities count for blueprint: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db->query_one<std::int64_t>(
+			"SELECT COUNT(*) FROM `entity_blueprint_links` WHERE `blueprint` = ?",
+			blueprint->id
+		)
+	);
+
+	return count;
+}

src/ikarus/objects/entity.cpp

@@ -80,6 +80,8 @@ IkarusEntity * ikarus_entity_copy(IkarusEntity * entity, IkarusEntityCopyFlags f
 				entity->id
 			));
 
+			auto const id = entity->project->db->last_insert_rowid();
+
 			CPPBASE_TRY(entity->project->db->execute(
 				"INSERT INTO `entity_values`(`entity`, `name`, `value`) "
 				"SELECT ?1, `name`, `value` FROM `entity_values` WHERE "
@@ -101,7 +103,7 @@ IkarusEntity * ikarus_entity_copy(IkarusEntity * entity, IkarusEntityCopyFlags f
 				entity->id
 			))
 
-			return cppbase::ok(entity->project->db->last_insert_rowid());
+			return cppbase::ok(id);
 		})
 	);
 
@@ -189,8 +191,8 @@ bool ikarus_entity_is_linked_to_blueprint(
 
 struct IkarusBlueprint **
 ikarus_entity_get_linked_blueprints(IkarusEntity * entity, size_t * size_out, IkarusErrorData * error_out) {
-	IKARUS_ASCERTAIN(false, "entity doesn't exist", IkarusErrorInfo_Client_NonExistent, ikarus_entity_exists, entity);
+	IKARUS_ASCERTAIN(nullptr, "entity doesn't exist", IkarusErrorInfo_Client_NonExistent, ikarus_entity_exists, entity);
-	IKARUS_VCALL(auto count, false, ikarus_entity_get_linked_blueprints_count, entity);
+	IKARUS_VCALL(auto count, nullptr, ikarus_entity_get_linked_blueprints_count, entity);
 
 	std::int64_t ids[count];
 
@@ -495,7 +497,7 @@ bool ikarus_entity_has_property_value(
 
 IkarusEntityPropertyValue *
 ikarus_entity_get_property_values(IkarusEntity * entity, size_t * size_out, IkarusErrorData * error_out) {
-	IKARUS_ASCERTAIN(false, "entity doesn't exist", IkarusErrorInfo_Client_NonExistent, ikarus_entity_exists, entity);
+	IKARUS_ASCERTAIN(nullptr, "entity doesn't exist", IkarusErrorInfo_Client_NonExistent, ikarus_entity_exists, entity);
 
 	IKARUS_VTRYRV_OR_FAIL(
 		auto values_plain,
@@ -503,8 +505,11 @@ ikarus_entity_get_property_values(IkarusEntity * entity, size_t * size_out, Ikar
 		"failed to get property values for entity: {}",
 		IkarusErrorInfo_Database_QueryFailed,
 		entity->project->db->query_many<int64_t, char const *>(
-			"SELECT `e`.`property`, IFNULL(`e`.`value`, ikarus_default_value(`p`.`schema`)) FROM `entity_property_values` AS `e` "
+			"SELECT `p`.`id`, IFNULL(`v`.`value`, ikarus_default_value(`p`.`schema`)) "
-			"INNER JOIN `properties` AS `p` ON `p`.`id` = `e`.`property` "
+			"FROM `entities` AS `e` "
+			"INNER JOIN `entity_blueprint_links` as `l` ON `l`.`entity` = `e`.`id` "
+			"INNER JOIN `properties` AS `p` ON `p`.`blueprint` = `l`.`blueprint` "
+			"LEFT JOIN `entity_property_values` AS `v` ON `e`.`entity` = `e`.`id` "
 			"WHERE `e`.`entity` = ?",
 			entity->id
 		)
@@ -527,9 +532,9 @@ ikarus_entity_get_property_values(IkarusEntity * entity, size_t * size_out, Ikar
 
 char const *
 ikarus_entity_get_property_value(IkarusEntity * entity, struct IkarusProperty * property, IkarusErrorData * error_out) {
-	IKARUS_ASCERTAIN(false, "entity doesn't exist", IkarusErrorInfo_Client_NonExistent, ikarus_entity_exists, entity);
+	IKARUS_ASCERTAIN(nullptr, "entity doesn't exist", IkarusErrorInfo_Client_NonExistent, ikarus_entity_exists, entity);
 	IKARUS_ASCERTAIN(
-		false,
+		nullptr,
 		"property doesn't exist",
 		IkarusErrorInfo_Client_NonExistent,
 		ikarus_property_exists,
@@ -543,6 +548,15 @@ ikarus_entity_get_property_value(IkarusEntity * entity, struct IkarusProperty *
 		IkarusErrorInfo_Client_NotLinked
 	);
 
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"entity doesn't have property value",
+		IkarusErrorInfo_Client_NotLinked,
+		ikarus_entity_has_property_value,
+		entity,
+		property
+	);
+
 	IKARUS_VTRYRV_OR_FAIL(
 		auto value,
 		nullptr,
@@ -567,6 +581,8 @@ void ikarus_entity_set_property_value(
 	IkarusEntitySetPropertyValueFlags flags,
 	IkarusErrorData * error_out
 ) {
+	IKARUS_FAIL_IF_NULL(value, IKARUS_VOID_RETURN);
+
 	IKARUS_ASCERTAIN(
 		IKARUS_VOID_RETURN,
 		"entity doesn't exist",
@@ -581,7 +597,6 @@ void ikarus_entity_set_property_value(
 		ikarus_property_exists,
 		property
 	);
-	IKARUS_FAIL_IF_NULL(value, IKARUS_VOID_RETURN);
 
 	IKARUS_FAIL_IF(
 		entity->project != property->project,
@@ -650,6 +665,7 @@ void ikarus_entity_clear_property_value(
 		"property does not belong to entity's project",
 		IkarusErrorInfo_Client_NotLinked
 	);
+
 	IKARUS_ASCERTAIN(
 		IKARUS_VOID_RETURN,
 		"entity doesn't have property",

src/ikarus/objects/property.cpp

@@ -2,9 +2,316 @@
 
 #include <ikarus/errors.h>
 #include <ikarus/errors.hpp>
+#include <ikarus/objects/blueprint.h>
 #include <ikarus/objects/property.h>
 #include <ikarus/persistence/project.hpp>
 
 IkarusProperty::IkarusProperty(struct IkarusProject * project, int64_t id):
 	project{project},
 	id{id} {}
+
+bool ikarus_property_exists(IkarusProperty * property, IkarusErrorData * error_out) {
+	IKARUS_FAIL_IF_NULL(property, false);
+	IKARUS_VTRYRV_OR_FAIL(
+		auto exists,
+		false,
+		"failed to check whether property exists: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		property->project->db->query_one<bool>("SELECT EXISTS(SELECT 1 FROM `properties` WHERE `id` = ?)", property->id)
+	);
+
+	return exists;
+}
+
+IkarusProperty * ikarus_property_create(
+	struct IkarusBlueprint * blueprint,
+	char const * name,
+	char const * schema,
+	char const * default_value,
+	IkarusPropertyCreateFlags flags,
+	IkarusErrorData * error_out
+) {
+	IKARUS_FAIL_IF_NULL(blueprint, nullptr);
+	IKARUS_FAIL_IF_NAME_INVALID(name, nullptr);
+
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"blueprint doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_blueprint_exists,
+		blueprint
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto schema_parsed,
+		nullptr,
+		"cannot parse schema as JSON: {}",
+		IkarusErrorInfo_Client_InvalidInput,
+		IkarusValueSchema::from_json_str(schema)
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto default_value_parsed,
+		nullptr,
+		"cannot parse default value as JSON: {}",
+		IkarusErrorInfo_Client_InvalidInput,
+		IkarusValueData::from_json_str(default_value)
+	);
+
+	IKARUS_FAIL_IF(
+		!schema_parsed.validate(default_value_parsed),
+		nullptr,
+		"default value is invalid for schema",
+		IkarusErrorInfo_Client_InvalidInput
+	);
+
+	IKARUS_TRYRV_OR_FAIL(
+		nullptr,
+		"failed to create property: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		blueprint->project->db->execute(
+			"INSERT INTO `properties`(`blueprint`, `name`, `schema`, `default_value`) VALUES(?, ?, ?, ?)",
+			blueprint->id,
+			name,
+			IkarusValueSchema::to_json(schema_parsed).dump(),
+			IkarusValueData::to_json(default_value_parsed).dump()
+		)
+	);
+
+	auto const id = blueprint->project->db->last_insert_rowid();
+	return new IkarusProperty{blueprint->project, id};
+}
+
+IkarusProperty *
+ikarus_property_copy(IkarusProperty * property, IkarusPropertyCopyFlags flags, IkarusErrorData * error_out) {
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"property doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_property_exists,
+		property
+	);
+
+	IKARUS_TRYRV_OR_FAIL(
+		nullptr,
+		"failed to copy property: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		property->project->db->execute(
+			"INSERT INTO `properties`(`blueprint`, `name`, `schema`, `default_value`) "
+			"SELECT `blueprint`, `name`, `schema`, `default_value` FROM `properties` WHERE `id` = ?",
+			property->id
+		)
+	);
+
+	auto const id = property->project->db->last_insert_rowid();
+	return new IkarusProperty{property->project, id};
+}
+
+void ikarus_property_delete(IkarusProperty * property, IkarusPropertyDeleteFlags flags, IkarusErrorData * error_out) {
+	IKARUS_ASCERTAIN(
+		IKARUS_VOID_RETURN,
+		"property doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_property_exists,
+		property
+	);
+
+	IKARUS_TRYRV_OR_FAIL(
+		IKARUS_VOID_RETURN,
+		"failed to delete property: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		property->project->db->execute("DELETE FROM `properties` WHERE `id` = ?", property->id)
+	);
+
+	delete property;
+}
+
+struct IkarusProject * ikarus_property_get_project(IkarusProperty * property, IkarusErrorData * error_out) {
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"property doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_property_exists,
+		property
+	);
+
+	return property->project;
+}
+
+char const * ikarus_property_get_name(IkarusProperty * property, IkarusErrorData * error_out) {
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"property doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_property_exists,
+		property
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto name,
+		nullptr,
+		"failed to get name for property: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		property->project->db->query_one<char const *>("SELECT `name` FROM `properties` WHERE `id` = ?", property->id)
+	);
+
+	return name;
+}
+
+void ikarus_property_set_name(
+	IkarusProperty * property,
+	char const * name,
+	IkarusPropertySetNameFlags flags,
+	IkarusErrorData * error_out
+) {
+	IKARUS_FAIL_IF_NULL(name, IKARUS_VOID_RETURN);
+	IKARUS_FAIL_IF_NAME_INVALID(name, IKARUS_VOID_RETURN);
+
+	IKARUS_TRYRV_OR_FAIL(
+		IKARUS_VOID_RETURN,
+		"failed to set name for property: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		property->project->db->execute("UPDATE `properties` SET `name` = ? WHERE `id` = ?", name, property->id)
+	);
+}
+
+char const * ikarus_property_get_schema(IkarusProperty * property, IkarusErrorData * error_out) {
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"property doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_property_exists,
+		property
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto schema,
+		nullptr,
+		"failed to get schema for property: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		property->project->db->query_one<char const *>("SELECT `schema` FROM `properties` WHERE `id` = ?", property->id)
+	);
+
+	return schema;
+}
+
+void ikarus_property_set_schema(
+	IkarusProperty * property,
+	char const * schema,
+	char const * new_default_value,
+	IkarusPropertySetSchemaFlags flags,
+	IkarusErrorData * error_out
+) {
+	IKARUS_FAIL_IF_NULL(schema, IKARUS_VOID_RETURN);
+	IKARUS_FAIL_IF_NULL(new_default_value, IKARUS_VOID_RETURN);
+
+	IKARUS_ASCERTAIN(
+		IKARUS_VOID_RETURN,
+		"property doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_property_exists,
+		property
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto schema_parsed,
+		IKARUS_VOID_RETURN,
+		"cannot parse schema as JSON: {}",
+		IkarusErrorInfo_Client_InvalidInput,
+		IkarusValueSchema::from_json_str(schema)
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto default_value_parsed,
+		IKARUS_VOID_RETURN,
+		"cannot parse default value as JSON: {}",
+		IkarusErrorInfo_Client_InvalidInput,
+		IkarusValueData::from_json_str(new_default_value)
+	);
+
+	IKARUS_FAIL_IF(
+		!schema_parsed.validate(default_value_parsed),
+		IKARUS_VOID_RETURN,
+		"default value is invalid for schema",
+		IkarusErrorInfo_Client_InvalidInput
+	);
+
+	// transact updating the property and all of its associated values
+	IKARUS_TRYRV_OR_FAIL(
+		IKARUS_VOID_RETURN,
+		"failed to set schema for property: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		property->project->db->transact([&](auto * db) -> cppbase::Result<void, sqlitecpp::TransactionError> {
+			CPPBASE_TRY(db->execute(
+				"UPDATE `properties` SET `schema` = ? WHERE `id` = ?",
+				IkarusValueSchema::to_json(schema_parsed).dump(),
+				property->id
+			));
+
+			CPPBASE_TRY(db->execute(
+				"UPDATE `entity_property_values` SET `value` = ? WHERE `property` = ?",
+				IkarusValueData::to_json(default_value_parsed).dump(),
+				property->id
+			));
+
+			return cppbase::ok();
+		})
+	);
+}
+
+char const * ikarus_property_get_default_value(IkarusProperty * property, IkarusErrorData * error_out) {
+	IKARUS_ASCERTAIN(
+		nullptr,
+		"property doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_property_exists,
+		property
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto default_value,
+		nullptr,
+		"failed to get default value for property: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		property->project->db
+			->query_one<char const *>("SELECT `default_value` FROM `properties` WHERE `id` = ?", property->id)
+	);
+
+	return default_value;
+}
+
+void ikarus_property_set_default_value(
+	IkarusProperty * property,
+	char const * value,
+	IkarusPropertySetDefaultValueFlags flags,
+	IkarusErrorData * error_out
+) {
+	IKARUS_FAIL_IF_NULL(value, IKARUS_VOID_RETURN);
+
+	IKARUS_ASCERTAIN(
+		IKARUS_VOID_RETURN,
+		"property doesn't exist",
+		IkarusErrorInfo_Client_NonExistent,
+		ikarus_property_exists,
+		property
+	);
+
+	IKARUS_VTRYRV_OR_FAIL(
+		auto value_parsed,
+		IKARUS_VOID_RETURN,
+		"cannot parse value as JSON: {}",
+		IkarusErrorInfo_Client_InvalidInput,
+		IkarusValueData::from_json_str(value)
+	);
+
+	IKARUS_TRYRV_OR_FAIL(
+		IKARUS_VOID_RETURN,
+		"failed to set default value for property: {}",
+		IkarusErrorInfo_Database_QueryFailed,
+		property->project->db->execute(
+			"UPDATE `properties` SET `default_value` = ? WHERE `id` = ?",
+			IkarusValueData::to_json(value_parsed).dump(),
+			property->id
+		)
+	);
+}

src/ikarus/persistence/migrations/m0_initial_layout.sql

@@ -10,8 +10,7 @@ CREATE TABLE `entity_values`
     `name`   TEXT    NOT NULL,
     `value`  TEXT    NOT NULL,
 
-    PRIMARY KEY (`id`),
+    PRIMARY KEY (`entity`, `name`)
-    UNIQUE (`entity`, `name`)
 ) STRICT;
 
 CREATE TABLE `blueprints`
@@ -44,6 +43,5 @@ CREATE TABLE `entity_property_values`
     `property` INTEGER NOT NULL REFERENCES `properties` (`id`) ON DELETE CASCADE,
     `value`    TEXT    NOT NULL,
 
-    PRIMARY KEY (`id`),
+    PRIMARY KEY (`entity`, `property`)
-    UNIQUE (`entity`, `property`)
 ) STRICT;