split property & values into separate classes and files

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

implementation_details

@@ -1,12 +0,0 @@
-This list is intended to help keep the documentation up to date.
-If you make changes to, for example, templates, always check the documentation for templates.
-But sometimes information is shared. and referenced in multiple places. This helps keep track of that.
-
-Usage: Search for these keys prefixed with IMPLEMENTATION_DETAIL_* to change documentation in relevant places.
-
-DATABASE: References to the usage of a database
-TREE_LAYOUT: References to our usage of a tree layout
-OBJECT_TYPES: References to the types of objects
-OBJECT_SCOPES: References to the usage of object scopes
-PROPERTY_TYPES: The property types that currently exist
-LAZY_VALUE_CREATION: The fact that values are created lazily

include/ikarus/objects/blueprint.h

@@ -77,7 +77,10 @@ IKA_API void ikarus_blueprint_get_linked_entities(
 /// \pre \li Must exist.
 /// \return The blueprint represented as an object or null if an error occurs.
 /// \remark This operation is guaranteed to be very fast and is intended to be used frequently.
-IKA_API struct IkarusObject * ikarus_blueprint_to_object(IkarusBlueprint const * blueprint);
+IKA_API struct IkarusObject * ikarus_blueprint_to_object(IkarusBlueprint * blueprint);
+
+/// \see ikarus_blueprint_to_object
+IKA_API struct IkarusObject const * ikarus_blueprint_to_object_const(IkarusBlueprint const * blueprint);
 
 IKARUS_END_HEADER
 

include/ikarus/objects/entity.h

@@ -50,12 +50,7 @@ struct IkarusEntity;
 /// \return The created entity or null if an error occurs.
 /// \remark Must be freed using #ikarus_free.
 IKA_API IkarusEntity * ikarus_entity_create(
-    struct IkarusProject * project,
-    struct IkarusEntityFolder * parent,
-    size_t position,
-    char const * name,
-    struct IkarusBlueprint ** blueprints,
-    size_t blueprints_count
+    struct IkarusProject * project, char const * name, struct IkarusBlueprint ** blueprints, size_t blueprints_count
 );
 
 /// \brief Deletes an entity.
@@ -67,16 +62,6 @@ IKA_API void ikarus_entity_delete(IkarusEntity * entity);
 
 IKA_API bool ikarus_entity_is_linked_to_blueprint(IkarusEntity const * entity, struct IkarusBlueprint const * blueprint);
 
-/// \brief Checks if an entity has a specific property.
-/// \param entity The entity to check.
-/// \pre \li Must not be null.
-/// \pre \li Must exist.
-/// \param property The property to check.
-/// \pre \li Must not be null.
-/// \pre \li Must exist.
-/// \return True if the entity has the property, false otherwise.
-IKA_API bool ikarus_entity_has_property(IkarusEntity const * entity, struct IkarusProperty const * property);
-
 /// \brief Links an entity to a blueprint.
 /// \param entity The entity to link.
 /// \pre \li Must not be null.
@@ -98,6 +83,16 @@ IKA_API void ikarus_entity_link_to_blueprint(IkarusEntity * entity, struct Ikaru
 /// \remark No-op if the entity is not linked to the blueprint.
 IKA_API void ikarus_entity_unlink_from_blueprint(IkarusEntity * entity, struct IkarusBlueprint * blueprint);
 
+/// \brief Checks if an entity has a specific property.
+/// \param entity The entity to check.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
+/// \param property The property to check.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
+/// \return True if the entity has the property, false otherwise.
+IKA_API bool ikarus_entity_has_property(IkarusEntity const * entity, struct IkarusProperty const * property);
+
 /// \brief Gets the number of properties of an entity.
 /// \param entity The entity to get the number of properties of.
 /// \pre \li Must not be null.
@@ -126,7 +121,7 @@ IKA_API void ikarus_entity_get_properties(
 /// \pre \li Must exist.
 /// \return The value of the property or null if the entity does not have the property or an error occurs.
 /// \remark Must be freed using #ikarus_free.
-IKA_API struct IkarusEntityValue * get_value(IkarusEntity const * entity, struct IkarusProperty const * property);
+IKA_API struct IkarusEntityValue * ikarus_entity_get_value(IkarusEntity const * entity, struct IkarusProperty const * property);
 
 /// \brief Sets the value of a property of an entity.
 /// \param entity The entity to set the value of.
@@ -138,11 +133,10 @@ IKA_API struct IkarusEntityValue * get_value(IkarusEntity const * entity, struct
 /// \param value The new value of the property.
 /// \pre \li Must not be null.
 /// \pre \li Must be of the same type as the property.
-/// \param validate_settings If set, this function fails not only if the type of the value is invalid, but also if it's not
-/// valid under the properties settings. \see property.h
+/// \pre \li Must be valid for the property's settings.
 /// \remark If the entity does not have the property, this function fails.
 IKA_API void ikarus_entity_set_value(
-    IkarusEntity * entity, struct IkarusProperty const * property, struct IkarusValue * value, bool validate_settings
+    IkarusEntity * entity, struct IkarusProperty const * property, struct IkarusValue const * value
 );
 
 /// \brief Casts an entity to an object.
@@ -151,7 +145,10 @@ IKA_API void ikarus_entity_set_value(
 /// \pre \li Must exist.
 /// \return The entity represented as an object or null if an error occurs.
 /// \remark This operation is guaranteed to be very fast and is intended to be used frequently.
-IKA_API struct IkarusObject * ikarus_entity_to_object(IkarusEntity const * entity);
+IKA_API struct IkarusObject * ikarus_entity_to_object(IkarusEntity * entity);
+
+/// \see ikarus_entity_to_object
+IKA_API struct IkarusObject const * ikarus_entity_to_object_const(IkarusEntity const * entity);
 
 IKARUS_END_HEADER
 

include/ikarus/objects/object.h

@@ -41,6 +41,18 @@ IKA_API void ikarus_object_visit(
     void * data
 );
 
+/// \see ikarus_object_visit
+IKA_API void ikarus_object_visit_const(
+    IkarusObject const * object,
+    void (*blueprint_visitor)(struct IkarusBlueprint const *, void *),
+    void (*property_visitor)(struct IkarusProperty const *, void *),
+    void (*entity_visitor)(struct IkarusEntity const *, void *),
+    void (*blueprint_folder_visitor)(struct IkarusBlueprintFolder const *, void *),
+    void (*property_folder_visitor)(struct IkarusPropertyFolder const *, void *),
+    void (*entity_folder_visitor)(struct IkarusEntityFolder const *, void *),
+    void * data
+);
+
 IKARUS_END_HEADER
 
 // @}

include/ikarus/objects/object_type.h

@@ -10,10 +10,7 @@
 
 IKARUS_BEGIN_HEADER
 
-// IMPLEMENTATION_DETAIL_OBJECT_TYPES
-
 /// \brief The type of an object.
-/// \remark The folder types are identical to their counterparts in #IkarusFolderType.
 enum IkarusObjectType {
     /// \brief Not an object or no object.
     IkarusObjectType_None = 0,

include/ikarus/objects/properties/number_property.h

@@ -0,0 +1,25 @@
+#pragma once
+
+/// \file number_property.h
+/// \author Folling <folling@ikarus.world>
+
+#include <ikarus/macros.h>
+
+/// \addtogroup properties Properties
+/// \brief Number properties store a numeric value. (e.g. "Weight" or "Age")
+/// @{
+
+IKARUS_BEGIN_HEADER
+
+struct IkarusNumberProperty;
+
+IKA_API IkarusNumberProperty * ikarus_number_property_create(
+    struct IkarusProject * project,
+    char const * name,
+    struct IkarusPropertySource * property_source,
+    struct IkarusNumberSettings * settings
+);
+
+IKARUS_END_HEADER
+
+/// @}

include/ikarus/objects/properties/property.h

@@ -1,12 +1,10 @@
 #pragma once
 
-// IMPLEMENTATION_DETAIL_LAZY_VALUE_CREATION
-
 /// \file property.h
 /// \author Folling <folling@ikarus.world>
 
 #include <ikarus/macros.h>
-#include <ikarus/objects/property_type.h>
+#include <ikarus/objects/properties/property_type.h>
 #include <ikarus/stdtypes.h>
 
 /// \defgroup properties Properties
@@ -52,33 +50,12 @@ IKARUS_BEGIN_HEADER
 /// \remark Properties' tree structures are scoped to the entity or blueprint they are associated with.
 struct IkarusProperty;
 
-/// \brief Creates a property
-/// \param project The project the property is part of.
-/// \pre \li Must not be null.
-/// \pre \li Must exist.
-/// \param property_source The property source the property is part of.
-/// \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 property_info The info of the property.
-/// \pre \li Must not be null.
-/// \return The created property or null if an error occurs.
-/// \remark Must be freed using #ikarus_free.
-IKA_API struct IkarusProperty * ikarus_property_create(
-    struct IkarusProject * project,
-    struct IkarusPropertySource * property_source,
-    char const * name,
-    struct IkarusPropertyTypeInfo * property_info
-);
-
 /// \brief Deletes a property.
 /// \param property The property to delete.
 /// \pre \li Must not be null.
 /// \pre \li Must exist.
 /// \remark The property must not be accessed after deletion.
-IKA_API void ikarus_property_delete(struct IkarusProperty * property);
+IKA_API void ikarus_property_delete(IkarusProperty * property);
 
 /// \brief Gets the type info of a property.
 /// \param property The property to get the type info of.
@@ -86,7 +63,18 @@ IKA_API void ikarus_property_delete(struct IkarusProperty * property);
 /// \pre \li Must exist.
 /// \return The type info of the property or null if an error occurs.
 /// \remark Must be freed using #ikarus_free.
-IKA_API struct IkarusPropertyTypeInfo * ikarus_property_get_type_info(IkarusProperty const * property);
+IKA_API IkarusPropertyType ikarus_property_get_type(IkarusProperty const * property);
+
+/// \brief Gets the settings of a property.
+/// \param property The property to get the settings of.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
+/// \return The settings of the property or null if an error occurs.
+/// \remark Must be freed using #ikarus_free.
+IKA_API struct IkarusPropertySettings * ikarus_property_get_settings(IkarusProperty * property);
+
+/// \see ikarus_property_get_settings
+IKA_API struct IkarusPropertySettings const * ikarus_property_get_settings_const(IkarusProperty const * property);
 
 /// \brief Gets the source of a property.
 /// \param property The property to get the source of.
@@ -94,25 +82,31 @@ IKA_API struct IkarusPropertyTypeInfo * ikarus_property_get_type_info(IkarusProp
 /// \pre \li Must exist.
 /// \return The source of the property or null if an error occurs.
 /// \remark Must be freed using #ikarus_free.
-IKA_API struct IkarusPropertySource * ikarus_property_get_source(IkarusProperty const * property);
+IKA_API struct IkarusPropertySource const * ikarus_property_get_source(IkarusProperty const * property);
 
-/// \brief Gets the default value of a property.
-/// \param property The property to get the default value of.
+/// \brief Visits a property. Calling the appropriate function for the property's type.
+/// \param property The property to visit.
 /// \pre \li Must not be null.
 /// \pre \li Must exist.
-/// \return The default value of the property or null if an error occurs.
-/// \remark Must be freed using #ikarus_free.
-IKA_API struct IkarusValue * ikarus_property_get_default_value(IkarusProperty const * property);
+/// \param toggle_property The function to call if the property is a toggle property. Skipped if null.
+/// \param number_property The function to call if the property is a number property. Skipped if null.
+/// \param text_property The function to call if the property is a text property. Skipped if null.
+/// \param data The data to pass to the functions.
+IKA_API void ikarus_property_visit(
+    IkarusProperty * property,
+    void (*toggle_property)(struct IkarusToggleProperty *, void *),
+    void (*number_property)(struct IkarusNumberProperty *, void *),
+    void (*text_property)(struct IkarusTextProperty *, void *),
+    void * data
+);
 
-/// \brief Sets the type info of a property and resets all values to the new default value.
-/// \param property The property to set the type info of.
-/// \pre \li Must not be null.
-/// \pre \li Must exist.
-/// \param new_type The new type info of the property.
-/// \param attempt_conversion Whether to attempt to convert the property's values to the new type info. Conversion rules are
-/// unspecified for now, but follow common sense.
-IKA_API void ikarus_property_set_type_info(
-    IkarusProperty * property, struct IkarusPropertyTypeInfo new_type_info, bool attempt_conversion
+/// \see ikarus_property_visit
+IKA_API void ikarus_property_visit_const(
+    IkarusProperty const * property,
+    void (*toggle_property)(struct IkarusToggleProperty const *, void *),
+    void (*number_property)(struct IkarusNumberProperty const *, void *),
+    void (*text_property)(struct IkarusTextProperty const *, void *),
+    void * data
 );
 
 /// \brief Casts a property to an object.
@@ -121,7 +115,10 @@ IKA_API void ikarus_property_set_type_info(
 /// \pre \li Must exist.
 /// \return The property represented as an object or null if an error occurs.
 /// \remark This operation is guaranteed to be very fast and is intended to be used frequently.
-IKA_API struct IkarusObject * ikarus_property_to_object(IkarusProperty const * property);
+IKA_API struct IkarusObject * ikarus_property_to_object(IkarusProperty * property);
+
+/// \see ikarus_property_to_object
+IKA_API struct IkarusObject const * ikarus_property_to_object_const(IkarusProperty const * property);
 
 IKARUS_END_HEADER
 

include/ikarus/objects/properties/property_source.h

@@ -10,7 +10,7 @@
 
 IKARUS_BEGIN_HEADER
 
-struct PropertySource;
+struct IkarusPropertySource;
 
 /// \brief Creates an blueprint property source.
 /// \param blueprint The blueprint to create the property source for.
@@ -18,7 +18,7 @@ struct PropertySource;
 /// \pre \li Must exist.
 /// \return The created property source or null if an error occurs.
 /// \remark Must be freed using #ikarus_free.
-IKA_API struct PropertySource * ikarus_property_source_create_blueprint(struct IkarusBlueprint * blueprint);
+IKA_API struct IkarusPropertySource * ikarus_property_source_create_blueprint(struct IkarusBlueprint * blueprint);
 
 /// \brief Creates an entity property source.
 /// \param entity The entity to create the property source for.
@@ -26,7 +26,7 @@ IKA_API struct PropertySource * ikarus_property_source_create_blueprint(struct I
 /// \pre \li Must exist.
 /// \return The created property source or null if an error occurs.
 /// \remark Must be freed using #ikarus_free.
-IKA_API struct PropertySource * ikarus_property_source_create_entity(struct IkarusEntity * entity);
+IKA_API struct IkarusPropertySource * ikarus_property_source_create_entity(struct IkarusEntity * entity);
 
 /// \brief Visits a property source, calling the appropriate callback.
 /// \param property_source The property source to visit.
@@ -36,12 +36,20 @@ IKA_API struct PropertySource * ikarus_property_source_create_entity(struct Ikar
 /// \param entity_visitor The callback to call if the source is an entity, skipped if null.
 /// \param user_data User data to pass to the callbacks.
 IKA_API void ikarus_property_source_visit(
-    struct PropertySource * property_source,
+    struct IkarusPropertySource * property_source,
     void (*blueprint_visitor)(struct IkarusBlueprint *, void *),
     void (*entity_visitor)(struct IkarusEntity *, void *),
     void * user_data
 );
 
+/// \see ikarus_property_source_visit
+IKA_API void ikarus_property_source_visit_const(
+    struct IkarusPropertySource const * property_source,
+    void (*blueprint_visitor)(struct IkarusBlueprint const *, void *),
+    void (*entity_visitor)(struct IkarusEntity const *, void *),
+    void * user_data
+);
+
 IKARUS_END_HEADER
 
 /// @}

include/ikarus/objects/properties/property_type.h

@@ -1,7 +1,5 @@
 #pragma once
 
-// IMPLEMENTATION_DETAIL_PROPERTY_TYPES
-
 /// \file property_type.h
 /// \author Folling <folling@ikarus.world>
 

include/ikarus/objects/properties/settings/number_property_settings.h

@@ -0,0 +1,31 @@
+#pragma once
+
+/// \file number_property_settings.h
+/// \author Folling <folling@ikarus.world>
+
+#include <ikarus/macros.h>
+
+/// \addtogroup property_settings PropertySettings
+/// \brief Number property settings add additional constraints to number properties.
+/// \details The following settings are available:
+///
+/// @{
+
+IKARUS_BEGIN_HEADER
+
+struct IkarusNumberPropertySettings;
+
+/// \brief Sets the default value for a number property.
+/// \param settings The number property settings.
+/// \pre \li Must not be null.
+/// \param default_value The default value.
+/// \pre \li Must not be null.
+/// \pre \li Must be a valid value for the property.
+/// \remark The settings take ownership of the value, the caller must not free it.
+IKA_API void ikarus_number_property_settings_set_default_value(
+    struct IkarusNumberPropertySettings * settings, struct IkarusNumberValue * default_value
+);
+
+IKARUS_END_HEADER
+
+/// @}

include/ikarus/objects/properties/settings/property_settings.h

@@ -0,0 +1,92 @@
+#pragma once
+
+/// \file property_settings.h
+/// \author Folling <folling@ikarus.world>
+
+#include <ikarus/macros.h>
+
+/// \defgroup property_settings PropertySettings
+/// \brief Property settings add additional constraints to properties.
+/// \details Each property has a certain set of settings. The options available depend on the type of the property.
+/// Settings can be changed after the property has been created. Examples of settings are:
+/// Note that the default value must be set using the concrete subtypes to ascertain type correctness.
+/// - Minimum: The minimum value for a number property.
+/// - Matches: A regular expression that the value of a text property must match.
+/// There are also some common settings, shared among all properties:
+/// - Default Value (default: PropertyType's default default (sic) value): The value that is returned if no value is specified
+/// for some entity.
+/// - List (default: false): If set to true, the property becomes a list. Instead of one number, you could then specify a series
+/// of numbers. Note that each element in the list is subject to changes in values. E.g. when we say that all values are changed
+/// in some way (e.g. reset to the default value), this applies to all elements in the list.
+/// - Allow undefined (default: false): If set to true, you can specify an "unknown" value for a property.
+/// It might not be known if a character is dead or not for example.
+/// @{
+
+IKARUS_BEGIN_HEADER
+
+struct IkarusPropertySettings;
+
+/// \brief Gets the default value of a property.
+/// \param settings The settings to get the default value of.
+/// \pre \li Must not be null.
+/// \pre \li Must exist.
+/// \return The default value of the property or null if an error occurs.
+/// \remark Must be freed using #ikarus_free.
+IKA_API struct IkarusValue const * ikarus_property_settings_get_default_value(IkarusPropertySettings const * settings);
+
+/// \brief Fetches whether a property is a list.
+/// \param settings The property settings.
+/// \pre \li Must not be null.
+/// \return True if the property is a list, false otherwise.
+IKA_API bool ikarus_property_settings_is_list(IkarusPropertySettings const * settings);
+
+/// \brief Sets whether a property is a list.
+/// \details Noop if unchanged. A change from list -> single truncates to just the first element. A change from single -> list
+/// sets the first element to the current value.
+/// \param settings The property settings.
+/// \pre \li Must not be null.
+/// \param list Whether the property should be
+/// a list.
+IKA_API void ikarus_property_settings_set_is_list(IkarusPropertySettings * settings, bool list);
+
+/// \brief Fetches whether a property may be undefined.
+/// \param settings The property settings.
+/// \pre \li Must not be null.
+/// \return True if the property may be undefined, false otherwise.
+IKA_API bool ikarus_property_settings_may_be_undefined(IkarusPropertySettings const * settings);
+
+/// \brief Sets whether a property may be undefined.
+/// \details Noop if unchanged. If the transition is from undefined -> defined, all undefined values will be reset to the
+/// default value.
+/// \param settings The property settings.
+/// \pre \li Must not be null.
+/// \param allow_undefined Whether the property should be allowed to be undefined.
+/// \param allow_undefined Whether the property should be allowed to be undefined.
+IKA_API void ikarus_property_settings_set_may_be_undefined(IkarusPropertySettings * settings, bool allow_undefined);
+
+/// \brief Visits a property settings. Calling the appropriate function for the property's type.
+/// \param settings The property settings.
+/// \pre \li Must not be null.
+/// \param toggle_property_visitor The function to call if the property is a toggle property. Skipped if null.
+/// \param number_property_visitor The function to call if the property is a number property. Skipped if null.
+/// \param text_property_visitor The function to call if the property is a text property. Skipped if null.
+/// \param data Data passed to the visitors.
+IKA_API void ikarus_property_settings_visit(
+    struct IkarusPropertySettings * settings,
+    void (*toggle_property_visitor)(struct IkarusTogglePropertySettings * settings, void * data),
+    void (*number_property_visitor)(struct IkarusNumberPropertySettings * settings, void * data),
+    void (*text_property_visitor)(struct IkarusTextPropertySettings * settings, void * data),
+    void * data
+);
+
+IKA_API void ikarus_property_settings_visit_const(
+    struct IkarusPropertySettings const * settings,
+    void (*toggle_property_visitor)(struct IkarusTogglePropertySettings const * settings, void * data),
+    void (*number_property_visitor)(struct IkarusNumberPropertySettings const * settings, void * data),
+    void (*text_property_visitor)(struct IkarusTextPropertySettings const * settings, void * data),
+    void * data
+);
+
+IKARUS_END_HEADER
+
+/// @}

include/ikarus/objects/properties/settings/text_property_settings.h

@@ -0,0 +1,31 @@
+#pragma once
+
+/// \file text_property_settings.h
+/// \author Folling <folling@ikarus.world>
+
+#include <ikarus/macros.h>
+
+/// \addtogroup property_settings PropertySettings
+/// \brief Text property settings add additional constraints to text properties.
+/// \details The following settings are available:
+///
+/// @{
+
+IKARUS_BEGIN_HEADER
+
+struct IkarusTextPropertySettings;
+
+/// \brief Sets the default value for a text property.
+/// \param settings The text property settings.
+/// \pre \li Must not be null.
+/// \param default_value The default value.
+/// \pre \li Must not be null.
+/// \pre \li Must be a valid value for the property.
+/// \remark The settings take ownership of the value, the caller must not free it.
+IKA_API void ikarus_text_property_settings_set_default_value(
+    struct IkarusTextPropertySettings * settings, struct IkarusTextValue * default_value
+);
+
+IKARUS_END_HEADER
+
+/// @}

include/ikarus/objects/properties/settings/toggle_property_settings.h

@@ -0,0 +1,31 @@
+#pragma once
+
+/// \file toggle_property_settings.h
+/// \author Folling <folling@ikarus.world>
+
+#include <ikarus/macros.h>
+
+/// \addtogroup property_settings PropertySettings
+/// \brief Toggle property settings add additional constraints to toggle properties.
+/// \details The following settings are available:
+///
+/// @{
+
+IKARUS_BEGIN_HEADER
+
+struct IkarusTogglePropertySettings;
+
+/// \brief Sets the default value for a toggle property.
+/// \param settings The toggle property settings.
+/// \pre \li Must not be null.
+/// \param default_value The default value.
+/// \pre \li Must not be null.
+/// \pre \li Must be a valid value for the property.
+/// \remark The settings take ownership of the value, the caller must not free it.
+IKA_API void ikarus_toggle_property_settings_set_default_value(
+    struct IkarusTogglePropertySettings * settings, struct IkarusToggleValue * default_value
+);
+
+IKARUS_END_HEADER
+
+/// @}

include/ikarus/objects/properties/text_property.h

@@ -0,0 +1,25 @@
+#pragma once
+
+/// \file text_property.h
+/// \author Folling <folling@ikarus.world>
+
+#include <ikarus/macros.h>
+
+/// \addtogroup properties Properties
+/// \brief Text properties store an arbitrary piece of text. (e.g. "Firstname" or "Description")
+/// @{
+
+IKARUS_BEGIN_HEADER
+
+struct IkarusTextProperty;
+
+IKA_API IkarusTextProperty * ikarus_text_property_create(
+    struct IkarusProject * project,
+    char const * name,
+    struct IkarusPropertySource * property_source,
+    struct IkarusTextSettings * settings
+);
+
+IKARUS_END_HEADER
+
+/// @}

include/ikarus/objects/properties/toggle_property.h

@@ -0,0 +1,25 @@
+#pragma once
+
+/// \file toggle_property.h
+/// \author Folling <folling@ikarus.world>
+
+#include <ikarus/macros.h>
+
+/// \addtogroup properties Properties
+/// \brief Toggle properties store a value that can be either true or false. (e.g. "Is the character dead?")
+/// @{
+
+IKARUS_BEGIN_HEADER
+
+struct IkarusToggleProperty;
+
+IKA_API IkarusToggleProperty * ikarus_toggle_property_create(
+    struct IkarusProject * project,
+    char const * name,
+    struct IkarusPropertySource * property_source,
+    struct IkarusToggleSettings * settings
+);
+
+IKARUS_END_HEADER
+
+/// @}

include/ikarus/objects/property_type_info.h

@@ -1,79 +0,0 @@
-#pragma once
-
-/// \file property_info.h
-/// \author Folling <folling@ikarus.world>
-
-#include <ikarus/macros.h>
-
-/// \addtogroup properties Properties
-/// @{
-
-IKARUS_BEGIN_HEADER
-
-/// \brief Information about a property.
-/// \details Property information includes their type and settings consolidated to ascertain type safety.
-struct IkarusPropertyTypeInfo;
-
-/// \brief Information about a toggle property.
-struct IkarusTogglePropertyInfo;
-
-/// \brief Information about a number property.
-struct IkarusNumberPropertyInfo;
-
-/// \brief Information about a text property.
-struct IkarusTextPropertyInfo;
-
-/// \brief Creates a new toggle property info.
-/// \return The created toggle property info.
-/// \remark Must be freed with #ikarus_free.
-IKA_API IkarusTogglePropertyInfo * ikarus_toggle_property_info_create();
-/// \brief Sets the default value of a toggle property info.
-/// \param toggle_property_info The toggle property info to set the default value of.
-/// \pre \li Must not be null.
-/// \param default_value The default value to set.
-/// \pre \li Must not be null.
-IKA_API void ikarus_toggle_property_info_set_default_value(
-    IkarusTogglePropertyInfo * toggle_property_info, struct IkarusToggleValue * default_value
-);
-/// \brief Converts a toggle property info to a generic property info.
-/// \param toggle_property_info The toggle property info to convert.
-/// \return The converted property info.
-IKA_API IkarusPropertyTypeInfo * ikarus_toggle_property_info_to_property_info(IkarusTogglePropertyInfo * toggle_property_info);
-
-/// \brief Creates a new number property info.
-/// \return The created number property info.
-/// \remark Must be freed with #ikarus_free.
-IKA_API IkarusNumberPropertyInfo * ikarus_number_property_info_create();
-/// \brief Sets the default value of a number property info.
-/// \param number_property_info The number property info to set the default value of.
-/// \pre \li Must not be null.
-/// \param default_value The default value to set.
-/// \pre \li Must not be null.
-IKA_API void ikarus_number_property_info_set_default_value(
-    IkarusNumberPropertyInfo * number_property_info, struct IkarusNumberValue * default_value
-);
-/// \brief Converts a number property info to a generic property info.
-/// \param number_property_info The number property info to convert.
-/// \return The converted property info.
-IKA_API IkarusPropertyTypeInfo * ikarus_number_property_info_to_property_info(IkarusNumberPropertyInfo * number_property_info);
-
-/// \brief Creates a new text property info.
-/// \return The created text property info.
-/// \remark Must be freed with #ikarus_free.
-IKA_API IkarusTextPropertyInfo * ikarus_text_property_info_create();
-/// \brief Sets the default value of a text property info.
-/// \param text_property_info The text property info to set the default value of.
-/// \pre \li Must not be null.
-/// \param default_value The default value to set.
-/// \pre \li Must not be null.
-IKA_API void ikarus_text_property_info_set_default_value(
-    IkarusTextPropertyInfo * text_property_info, struct IkarusTextValue * default_value
-);
-/// \brief Converts a text property info to a generic property info.
-/// \param text_property_info The text property info to convert.
-/// \return The converted property info.
-IKA_API IkarusPropertyTypeInfo * ikarus_text_property_info_to_property_info(IkarusTextPropertyInfo * text_property_info);
-
-IKARUS_END_HEADER
-
-/// @}

include/ikarus/values/number_value.h

@@ -0,0 +1,44 @@
+#pragma once
+
+/// \file number_value.h
+/// \author Folling <folling@ikarus.world>
+
+#include <ikarus/macros.h>
+
+/// \addtogroup entity_value Entity Values
+/// @{
+
+IKARUS_BEGIN_HEADER
+
+/// \brief A true/false boolean-like value. For example "IsDead".
+struct IkarusNumberValue;
+
+/// \brief Creates a number value from a long double.
+/// \param value The numeric value.
+/// \return The entity value.
+/// \remark Must be freed with #ikarus_free.
+IKA_API IkarusNumberValue * ikarus_number_value_create(long double value);
+
+/// \brief Creates an indeterminate number value.
+/// \return The entity value.
+/// \remark Must be freed with #ikarus_free.
+IKA_API IkarusNumberValue * ikarus_number_value_create_indeterminate();
+
+/// \brief Sets the value of a number value.
+/// \param value The number value.
+/// \pre \li Must not be null.
+/// \param new_value The new value.
+IKA_API void ikarus_number_value_set(IkarusNumberValue * value, bool new_value);
+
+/// \brief Fetches the underlying value of a number value.
+/// \param value The number value.
+/// \return The underlying value.
+/// \warning If the value is indeterminate, false is returned.
+IKA_API long double ikarus_number_value_get_underlying(IkarusNumberValue const * value);
+
+/// \brief Converts a number value to an entity value.
+/// \param number_value The number value to convert.
+/// \return The converted entity value.
+IKA_API struct IkarusEntityValue * ikarus_number_value_to_entity_value(IkarusNumberValue * number_value);
+
+IKARUS_END_HEADER

include/ikarus/values/text_value.h

@@ -0,0 +1,44 @@
+#pragma once
+
+/// \file text_value.h
+/// \author Folling <folling@ikarus.world>
+
+#include <ikarus/macros.h>
+
+/// \addtogroup entity_value Entity Values
+/// @{
+
+IKARUS_BEGIN_HEADER
+
+/// \brief A true/false boolean-like value. For example "IsDead".
+struct IkarusTextValue;
+
+/// \brief Creates a text value from a boolean.
+/// \param value The text value.
+/// \return The entity value.
+/// \remark Must be freed with #ikarus_free.
+IKA_API IkarusTextValue * ikarus_text_value_create(char const * value);
+
+/// \brief Creates an indeterminate text value.
+/// \return The entity value.
+/// \remark Must be freed with #ikarus_free.
+IKA_API IkarusTextValue * ikarus_text_value_create_indeterminate();
+
+/// \brief Sets the value of a text value.
+/// \param value The text value.
+/// \pre \li Must not be null.
+/// \param new_value The new value.
+IKA_API void ikarus_text_value_set(IkarusTextValue * value, bool new_value);
+
+/// \brief Fetches the underlying value of a text value.
+/// \param value The text value.
+/// \return The underlying value.
+/// \warning If the value is indeterminate, false is returned.
+IKA_API char const * ikarus_text_value_get_underlying(IkarusTextValue const * value);
+
+/// \brief Converts a text value to an entity value.
+/// \param text_value The text value to convert.
+/// \return The converted entity value.
+IKA_API struct IkarusEntityValue * ikarus_text_value_to_entity_value(IkarusTextValue * text_value);
+
+IKARUS_END_HEADER

include/ikarus/values/toggle_value.h

@@ -0,0 +1,44 @@
+#pragma once
+
+/// \file toggle_value.h
+/// \author Folling <folling@ikarus.world>
+
+#include <ikarus/macros.h>
+
+/// \addtogroup entity_value Entity Values
+/// @{
+
+IKARUS_BEGIN_HEADER
+
+/// \brief A true/false boolean-like value. For example "IsDead".
+struct IkarusToggleValue;
+
+/// \brief Creates a toggle value from a boolean.
+/// \param value The toggle value.
+/// \return The entity value.
+/// \remark Must be freed with #ikarus_free.
+IKA_API IkarusToggleValue * ikarus_toggle_value_create(bool value);
+
+/// \brief Creates an indeterminate toggle value.
+/// \return The entity value.
+/// \remark Must be freed with #ikarus_free.
+IKA_API IkarusToggleValue * ikarus_toggle_value_create_indeterminate();
+
+/// \brief Sets the value of a toggle value.
+/// \param value The toggle value.
+/// \pre \li Must not be null.
+/// \param new_value The new value.
+IKA_API void ikarus_toggle_value_set(IkarusToggleValue * value, bool new_value);
+
+/// \brief Fetches the underlying value of a toggle value.
+/// \param value The toggle value.
+/// \return The underlying value.
+/// \warning If the value is indeterminate, false is returned.
+IKA_API bool ikarus_toggle_value_get_underlying(IkarusToggleValue const * value);
+
+/// \brief Converts a toggle value to an entity value.
+/// \param toggle_value The toggle value to convert.
+/// \return The converted entity value.
+IKA_API struct IkarusEntityValue * ikarus_toggle_value_to_entity_value(IkarusToggleValue * toggle_value);
+
+IKARUS_END_HEADER

include/ikarus/values/value.h

@@ -1,16 +1,11 @@
 #pragma once
 
-// IMPLEMENTATION_DETAIL_PROPERTY_TYPES
-
 /// \file value.h
 /// \author Folling <folling@ikarus.world>
 
 #include <ikarus/macros.h>
-#include <ikarus/objects/property_type.h>
 #include <ikarus/stdtypes.h>
 
-IKARUS_BEGIN_HEADER
-
 /// \defgroup entity_value Entity Values
 /// \brief The values stored in entities.
 /// \details Each entity has a value for each property it is associated with.
@@ -19,112 +14,47 @@ IKARUS_BEGIN_HEADER
 /// \see PropertyType PropertySettings
 /// @{
 
-/// \brief A true/false boolean-like value. For example "IsDead".
-struct IkarusToggleValue;
+IKARUS_BEGIN_HEADER
 
-/// \brief An arbitrary numeric value. For example "Age".
-struct IkarusNumberValue;
+/// \brief The common type for all values.
+struct IkarusValue;
 
-/// \brief An arbitrary textual value. For example "First Name".
-struct IkarusTextValue;
-
-/// \brief The value of an entity associated with a property.
-struct IkarusEntityValue;
-
-/// \brief Creates a toggle value from a boolean.
-/// \param value The toggle value.
-/// \return The entity value.
-/// \remark Must be freed with #ikarus_free.
-IKA_API IkarusToggleValue * ikarus_toggle_value_create(bool value);
-/// \brief Creates an indeterminate toggle value.
-/// \return The entity value.
-/// \remark Must be freed with #ikarus_free.
-IKA_API IkarusToggleValue * ikarus_toggle_value_create_indeterminate();
-/// \brief Sets the value of a toggle value.
-/// \param value The toggle value.
-/// \pre Must not be null.
-/// \param new_value The new value.
-IKA_API void ikarus_toggle_value_set(IkarusToggleValue * value, bool new_value);
-
-/// \brief Creates a number value from a number.
-/// \param value The number value.
-/// \pre Must be finite & not NaN.
-/// \return The entity value.
-/// \remark Must be freed with #ikarus_free.
-IKA_API IkarusNumberValue * ikarus_number_value_create(long double value);
-/// \brief Creates an indeterminate number value.
-/// \return The entity value.
-/// \remark Must be freed with #ikarus_free.
-IKA_API IkarusNumberValue * ikarus_number_value_create_indeterminate();
-/// \brief Sets the value of a number value.
-/// \param value The number value.
-/// \pre Must not be null.
-/// \param new_value The new value.
-IKA_API void ikarus_number_value_set(IkarusNumberValue * value, bool new_value);
-
-/// \brief Creates a text value from string.
-/// \param value The text value.
-/// \pre Must not be null.
-/// \return The entity value.
-/// \remark Must be freed with #ikarus_free.
-IKA_API IkarusTextValue * ikarus_text_value_create(char const * value);
-/// \brief Creates an indeterminate text value.
-/// \return The entity value.
-/// \remark Must be freed with #ikarus_free.
-IKA_API IkarusTextValue * ikarus_text_value_create_indeterminate();
-/// \brief Sets the value of a text value.
-/// \param value The text value.
-/// \pre Must not be null.
-/// \param new_value The new value.
-IKA_API void ikarus_text_value_set(IkarusTextValue * value, bool new_value);
-
-/// \brief Checks if a toggle value is indeterminate.
-/// \param value The toggle value.
-/// \pre Must not be null.
+/// \brief Checks if a value is indeterminate.
+/// \param value The value.
+/// \pre \li Must not be null.
 /// \return True if the value is indeterminate, false otherwise.
-IKA_API bool ikarus_toggle_value_is_indeterminate(IkarusToggleValue const * value);
-/// \brief Checks if a number value is indeterminate.
-/// \param value The number value.
-/// \pre Must not be null.
-/// \return True if the value is indeterminate, false otherwise.
-IKA_API bool ikarus_number_value_is_indeterminate(IkarusNumberValue const * value);
-/// \brief Checks if a text value is indeterminate.
-/// \param value The text value.
-/// \pre Must not be null.
-/// \return True if the value is indeterminate, false otherwise.
-IKA_API bool ikarus_text_value_is_indeterminate(IkarusTextValue const * value);
+IKA_API bool ikarus_value_is_indeterminate(IkarusValue const * value);
 
-/// \brief Fetches the underlying value of a toggle value.
-/// \param value The toggle value.
-/// \return The underlying value.
-/// \warning If the value is indeterminate, false is returned.
-IKA_API bool ikarus_toggle_value_get_underlying(IkarusToggleValue const * value);
-
-/// \brief Fetches the underlying value of a number value.
-/// \param value The number value.
-/// \return The underlying value.
-/// \warning If the value is indeterminate, 0.0 is returned.
-IKA_API long double ikarus_number_value_get_underlying(IkarusNumberValue const * value);
-
-/// \brief Fetches the underlying value of a text value.
-/// \param value The text value.
-/// \return A copy of the underlying value.
-/// \remark The returned value is a copy and owned by the caller.
-/// \warning If the value is indeterminate, an empty string is returned.
-IKA_API char const * ikarus_text_value_get_underlying(IkarusTextValue const * value);
+// \brief Converts an entity value to a string.
+// \pre \li Must not be null.
+// \param value The entity value.
+// \return A string representation of the value or null if an error occurred.
+// \remark The returned value is a copy and owned by the caller.
+IKA_API char const * ikarus_value_to_string(IkarusValue const * value);
 
 /// \brief Visits an entity value, calling the appropriate function for the value's type.
 /// \param value The entity value to visit.
-/// \param toggle The function to call if the value is a toggle value. Skipped if null.
-/// \param number The function to call if the value is a number value. Skipped if null.
-/// \param text The function to call if the value is a text value. Skipped if null.
+/// \param toggle_visitor The function to call if the value is a toggle value. Skipped if null.
+/// \param number_visitor The function to call if the value is a number value. Skipped if null.
+/// \param text_visitor The function to call if the value is a text value. Skipped if null.
 /// \param data The data passed to the visitor functions.
 IKA_API void ikarus_value_visit(
-    IkarusEntityValue * value,
-    void (*toggle)(IkarusToggleValue *, void *),
-    void (*number)(IkarusNumberValue *, void *),
-    void (*text)(IkarusTextValue *, void *),
+    IkarusValue * value,
+    void (*toggle_visitor)(struct IkarusToggleValue *, void *),
+    void (*number_visitor)(struct IkarusNumberValue *, void *),
+    void (*text_visitor)(struct IkarusTextValue *, void *),
+    void * data
+);
+
+/// \see ikarus_value_visit
+IKA_API void ikarus_value_visit_const(
+    IkarusValue const * value,
+    void (*toggle_visitor)(struct IkarusToggleValue const *, void *),
+    void (*number_visitor)(struct IkarusNumberValue const *, void *),
+    void (*text_visitor)(struct IkarusTextValue const *, void *),
     void * data
 );
 
 IKARUS_END_HEADER
+
+/// @}

src/objects/blueprint.cpp

@@ -5,10 +5,7 @@
 #include <cppbase/strings.hpp>
 
 #include <ikarus/objects/blueprint.h>
-#include <ikarus/objects/entity.h>
-#include <ikarus/objects/object_type.h>
 
-#include <id.hpp>
 #include <objects/entity.hpp>
 #include <objects/property.hpp>
 #include <persistence/project.hpp>

src/objects/property.cpp

@@ -0,0 +1,87 @@
+#include "property.hpp"
+
+#include <cppbase/logger.hpp>
+#include <cppbase/result.hpp>
+#include <cppbase/strings.hpp>
+
+#include <ikarus/values/value.h>
+
+#include <objects/blueprint.hpp>
+#include <objects/entity.hpp>
+#include <objects/property.hpp>
+#include <objects/property_info.hpp>
+#include <objects/property_source.hpp>
+#include <persistence/project.hpp>
+
+IkarusProperty * ikarus_property_create(
+    struct IkarusProject * project,
+    char const * name,
+    struct IkarusPropertySource * property_source,
+    struct IkarusPropertyInfo * property_info
+) {
+    LOG_INFO("creating new property");
+
+    if (project == nullptr) {
+        LOG_ERROR("project is nullptr");
+        return nullptr;
+    }
+
+    auto ctx = project->function_context();
+
+    if (property_source == nullptr) {
+        ctx->set_error("property_source is nullptr", true, IkarusErrorInfo_Source_Client, IkarusErrorInfo_Type_Client_Input);
+        return nullptr;
+    }
+
+    if (name == nullptr) {
+        ctx->set_error("name is nullptr", true, IkarusErrorInfo_Source_Client, IkarusErrorInfo_Type_Client_Input);
+        return nullptr;
+    }
+
+    if (cppbase::is_empty_or_blank(name)) {
+        ctx->set_error("name is empty or blank", true, IkarusErrorInfo_Source_Client, IkarusErrorInfo_Type_Client_Input);
+        return nullptr;
+    }
+
+    if (property_info == nullptr) {
+        ctx->set_error("property_info is nullptr", true, IkarusErrorInfo_Source_Client, IkarusErrorInfo_Type_Client_Input);
+        return nullptr;
+    }
+
+    LOG_VERBOSE(
+        "project={}; name={}; property_source={}; property_info={}",
+        project->path().c_str(),
+        name,
+        std::visit(
+            cppbase::overload{
+                [](IkarusBlueprint * blueprint) { return fmt::format("Blueprint({})", blueprint->id); },
+                [](IkarusEntity * entity) { return fmt::format("Entity({})", entity->id); }},
+            property_source->data
+        ),
+        std::visit(
+            cppbase::overload{
+                [](IkarusTogglePropertyInfo * info) {
+                    return fmt::format(
+                        "Toggle(default_value={})",
+                        cppbase::OwningString{ikarus_value_to_string(ikarus_toggle_value_to_entity_value(info->default_value))}
+                            .data
+                    );
+                },
+                [](IkarusNumberPropertyInfo * info) {
+                    return fmt::format(
+                        "Number(default_value={})",
+                        cppbase::OwningString{ikarus_value_to_string(ikarus_number_value_to_entity_value(info->default_value))}
+                            .data
+                    );
+                },
+                [](IkarusTextPropertyInfo * info) {
+                    return fmt::format(
+                        "Text(default_value={})",
+                        cppbase::OwningString{ikarus_value_to_string(ikarus_text_value_to_entity_value(info->default_value))}
+                            .data
+                    );
+                }},
+            property_info->data
+        )
+    );
+}

src/objects/property_info.hpp

@@ -0,0 +1,74 @@
+#pragma once
+
+#include <variant>
+
+#include <ikarus/objects/property_info.h>
+
+#include <values/number_value.hpp>
+#include <values/text_value.hpp>
+#include <values/toggle_value.hpp>
+
+// this looks a bit cursed, but there's reason to my madness:
+// Let's go over the facts:
+// 1. The client uses the concrete types (e.g. Ikarus"Toggle"PropertyInfo)
+// 2. The API needs to accept a common type (i.e. IkarusPropertyInfo)
+// 3. Casting between a concrete subtype and a common type is only defined behaviour if we use inheritance, otherwise an
+// allocation is unavoidable
+// 4. On the implementation side, we need to be able to distinguish between the concrete types
+//
+// There's a few ways to model this (using dynamic_casts, using an enum, a union, the visitor pattern, ...) but std::variant
+// gives us the most type safety without any performance overhead
+
+/// \private
+struct IkarusPropertyInfo {
+public:
+    using IkarusPropertyInfoData =
+        std::variant<struct IkarusTogglePropertyInfo *, struct IkarusNumberPropertyInfo *, struct IkarusTextPropertyInfo *>;
+
+public:
+    inline explicit IkarusPropertyInfo(
+        std::variant<struct IkarusTogglePropertyInfo *, struct IkarusNumberPropertyInfo *, struct IkarusTextPropertyInfo *> data
+    ):
+        data{data} {}
+
+public:
+    [[nodiscard]] inline IkarusPropertyInfoData const& get_data() const {
+        return data;
+    }
+
+private:
+    IkarusPropertyInfoData data;
+};
+
+/// \private
+struct IkarusTogglePropertyInfo : public IkarusPropertyInfo {
+public:
+    inline IkarusTogglePropertyInfo():
+        IkarusPropertyInfo{this} {}
+
+public:
+    [[nodiscard]] IkarusToggleValue * get_default_value() const {}
+
+private:
+    IkarusToggleValue * default_value{nullptr};
+};
+
+/// \private
+struct IkarusNumberPropertyInfo : public IkarusPropertyInfo {
+public:
+    inline IkarusNumberPropertyInfo():
+        IkarusPropertyInfo{this} {}
+
+private:
+    IkarusNumberValue * default_value{nullptr};
+};
+
+/// \private
+struct IkarusTextPropertyInfo : public IkarusPropertyInfo {
+public:
+    inline IkarusTextPropertyInfo():
+        IkarusPropertyInfo{this} {}
+
+private:
+    IkarusTextValue * default_value{nullptr};
+};

src/objects/property_source.hpp

@@ -0,0 +1,10 @@
+#pragma once
+
+#include <variant>
+
+#include <ikarus/objects/property_source.h>
+
+/// \private
+struct IkarusPropertySource {
+    std::variant<IkarusBlueprint *, IkarusEntity *> data;
+};

src/persistence/project.hpp

@@ -13,6 +13,7 @@
 constexpr inline size_t MAXIMUM_ERROR_INFOS = 8;
 constexpr inline size_t MAXIMUM_ERROR_MESSAGE_LENGTH = 256;
 
+/// \private
 class FunctionContext {
 public:
     explicit FunctionContext(struct IkarusProject * project);
@@ -128,7 +129,7 @@ FunctionContext::~FunctionContext() {
 
 template<typename... Infos>
     requires(std::is_same_v<IkarusErrorInfo, Infos> && ...) && (sizeof...(Infos) <= MAXIMUM_ERROR_INFOS)
-auto FunctionContext::set_error(std::string_view error_message, bool log_error, Infos... infos) {
+auto FunctionContext::set_error(std::string_view error_message, bool log_error, Infos... infos) -> void {
     if (error_message.size() > _project->error_message_buffer.size()) {
         _project->error_message_buffer.resize(error_message.size() + 1);
     }

src/values/number_value.hpp

@@ -0,0 +1,5 @@
+#pragma once
+
+struct IkarusNumberValue {
+    long double value;
+};

src/values/text_value.hpp

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <string>
+
+/// \private
+struct IkarusTextValue {
+    std::string value;
+};

src/values/toggle_value.hpp

@@ -0,0 +1,6 @@
+#pragma once
+
+/// \private
+struct IkarusToggleValue {
+    bool value;
+};