import DragEvent from '../../dragobserver/DragEvent';
import PresentationBoxType from '../PresentationBoxType';
/**
 * [[PresentationContentPlacement]] describes the rectangular placement of the
 * content within its parent viewport.
 */
export interface PresentationContentPlacement {
    /**
     * The width and height of the content in CSS pixels.
     */
    dimensions: [number, number];
    /**
     * The left and top translations of the content in CSS pixels relative to the viewport
     */
    translations: [number, number];
}
/**
 * [[PresentationState]] represents everything known about the current placement
 * of the content within its parent viewport.
 */
export interface PresentationState {
    /**
     * The width and height of the viewport in CSS pixels.
     */
    viewportDimensions: [number, number];
    /**
     * The viewport width over height aspect ratio. For example if the viewport
     * has dimensions 640 x 480 then its aspect ratio is `1.33...`.
     */
    viewportAspectRatio: number;
    /**
     * The current content placement.
     */
    contentPlacement: PresentationContentPlacement;
    /**
     * The source width and height of the content.
     */
    sourceDimensions: [number, number];
    /**
     * The source width over height aspect ratio. For example if the content
     * has source dimensions 640 x 480 then its aspect ratio is `1.33...`.
     */
    sourceAspectRatio: number;
    /**
     * The size of the content relative to its source size. This is calculated
     * using the x-dimension, e.g. the content CSS pixel width divided by the
     * content source width. For example, if the source dimensions are 640 x 480
     * but the content CSS dimensions are currently 320 x 240 then the scale is
     * 0.5 (i.e. a zoom factor of 50%).
     */
    scale: number;
    /**
     * True if the source aspect ratio is greater than the viewport aspect ratio,
     * which indicates that a letterbox fit would be appropriate (gaps on top
     * and bottom) if the entire content is to be scaled to fit within the viewport.
     * Note that both [[letterBox]] and [[pillarBox]] will be false if the aspect
     * ratio of the source dimensions and the viewport match exactly.
     */
    boxType: PresentationBoxType;
    focus: {
        normalizedContentFocus: [number, number];
        normalizedViewportFocus: [number, number];
    };
}
export declare enum ZoomType {
    ZOOM = 0,
    RESET = 1,
    NONE = 2
}
export interface ZoomEvent {
    type: ZoomType;
    relativeFactor?: number;
    absoluteFactor?: number;
}
export interface PresentationUpdateEvent {
    drag?: DragEvent;
    zoom?: ZoomEvent;
}
export default interface PresentationPolicy {
    calculate: (state: PresentationState, updateEvent?: PresentationUpdateEvent) => PresentationContentPlacement;
}