package tomo

import "image"

// LayoutEntry associates an element with layout and positioning information so
// it can be arranged by a Layout.
type LayoutEntry struct {
	Element
	Position image.Point
	Expand bool
}

// Layout is capable of arranging elements within a container. It is also able
// to determine the minimum amount of room it needs to do so.
type Layout interface {
	// Arrange takes in a slice of entries and a bounding width and height,
	// and changes the position of the entiries in the slice so that they
	// are properly laid out. The given width and height should not be less
	// than what is returned by MinimumSize.
	Arrange (entries []LayoutEntry, width, height int)

	// MinimumSize returns the minimum width and height that the layout
	// needs to properly arrange the given slice of layout entries.
	MinimumSize (entries []LayoutEntry) (width, height int)

	// FlexibleHeightFor Returns the minimum height the layout needs to lay
	// out the specified elements at the given width, taking into account
	// flexible elements.
	FlexibleHeightFor (entries []LayoutEntry, squeeze int) (height int)
}