#pragma once

// IMPLEMENTATION_DETAIL_LAZY_VALUE_CREATION, IMPLEMENTATION_DETAIL_PROPERTY_TYPES

/// \file property.h
/// \author Folling <mail@folling.io>

#include <ikarus/id.h>
#include <ikarus/macros.h>
#include <ikarus/objects/blueprint.h>
#include <ikarus/objects/entity.h>

/// \defgroup properties Properties
/// \brief Properties define the structure and types of data.

IKARUS_BEGIN_HEADER

/// \brief Properties are the placeholders of values for entities.
/// \details Each entity can have any number of properties.
/// Every property has a type that identifies the kind of data that can be put in.
///
/// The following types currently exist:
/// - Toggle: A true/false boolean-like value
/// - Number: An arbitrary numeric value
/// - Text: An arbitrary textual value
///
/// Property Examples:
/// - Is Dead (Toggle)
/// - Age (Number)
/// - ISBN (Text)
///
/// Every property has settings which can be used to customise the property further.
/// Two settings that are shared among all properties are the following:
/// - Multiple
/// - Allow undefined
///
/// The former transforms a property into a list. Instead of one number, you could then specify a series of numbers.
/// The latter allows you to specify an "unknown" value for a property.
/// It might not be known if a character is dead or not for example.
///
/// Each entity associated with the property has a value for it.
///
/// Properties can also be added to blueprints in which case they are available for all entities associated with the
/// blueprint.
///
/// We call properties within entities "Entity Properties" and properties within blueprints "Blueprint Properties".
///
/// \remark Properties are scoped to the blueprint or entity they are associated with.
/// \remark Values for properties are lazily created as space saving measure.
/// Fetching the value for some property of some entity will return the property's default value if none is specified.
/// This default value is specified when the property is created and can be updated later.
/// \remark Properties' tree structures are scoped to the entity or blueprint they are associated with.
struct IkarusProperty {
    /// \private \brief The id of the property.
    IkarusId id;
};

/// \brief The type of a property.
/// \details Designates the type of data stored by the property as well as which settings are
/// available.
/// \see IkarusPropertySettings
enum IkarusPropertyType {
    /// \brief A true/false boolean-like value.
    IkarusPropertyType_Toggle,
    /// \brief An arbitrary numeric value.
    IkarusPropertyType_Number,
    /// \brief An arbitrary textual value.
    IkarusPropertyType_Text,
};

IKARUS_END_HEADER

// @}