#pragma once

#include <set>

#include "core/Phone.h"
#include "core/Shape.h"
#include "time/Timeline.h"

// Returns the basic shape (A-F) that most closely resembles the specified shape.
Shape getBasicShape(Shape shape);

// Returns the mouth shape that results from relaxing the specified shape.
Shape relax(Shape shape);

// Gets the shape from a non-empty set of shapes that most closely resembles a reference shape.
Shape getClosestShape(Shape reference, ShapeSet shapes);

// Indicates how to time a tween between two mouth shapes
enum class TweenTiming {
    // Tween should end at the original transition
    Early,

    // Tween should overlap both original mouth shapes equally
    Centered,

    // Tween should begin at the original transition
    Late
};

// Returns the tween shape and timing to use to transition between the specified two mouth shapes.
boost::optional<std::pair<Shape, TweenTiming>> getTween(Shape first, Shape second);

// Returns the shape set(s) to use for a given phone.
// The resulting timeline will always cover the entire duration of the phone (starting at 0 cs).
// It may extend into the negative time range if animation is required prior to the sound being
// heard.
Timeline<ShapeSet> getShapeSets(Phone phone, centiseconds duration, centiseconds previousDuration);