import { BoundingBox } from '../Collision/BoundingBox';
import { Color } from '../Color';
import { Vector } from '../Math/vector';
import { ExcaliburGraphicsContext } from './Context/ExcaliburGraphicsContext';
/**
 * Enum representing the different font size units
 * https://developer.mozilla.org/en-US/docs/Web/CSS/font-size
 */
export declare enum FontUnit {
    /**
     * Em is a scalable unit, 1 em is equal to the current font size of the current element, parent elements can effect em values
     */
    Em = "em",
    /**
     * Rem is similar to the Em, it is a scalable unit. 1 rem is equal to the font size of the root element
     */
    Rem = "rem",
    /**
     * Pixel is a unit of length in screen pixels
     */
    Px = "px",
    /**
     * Point is a physical unit length (1/72 of an inch)
     */
    Pt = "pt",
    /**
     * Percent is a scalable unit similar to Em, the only difference is the Em units scale faster when Text-Size stuff
     */
    Percent = "%"
}
/**
 * Enum representing the different horizontal text alignments
 */
export declare enum TextAlign {
    /**
     * The text is left-aligned.
     */
    Left = "left",
    /**
     * The text is right-aligned.
     */
    Right = "right",
    /**
     * The text is centered.
     */
    Center = "center",
    /**
     * The text is aligned at the normal start of the line (left-aligned for left-to-right locales,
     * right-aligned for right-to-left locales).
     */
    Start = "start",
    /**
     * The text is aligned at the normal end of the line (right-aligned for left-to-right locales,
     * left-aligned for right-to-left locales).
     */
    End = "end"
}
/**
 * Enum representing the different baseline text alignments
 */
export declare enum BaseAlign {
    /**
     * The text baseline is the top of the em square.
     */
    Top = "top",
    /**
     * The text baseline is the hanging baseline.  Currently unsupported; this will act like
     * alphabetic.
     */
    Hanging = "hanging",
    /**
     * The text baseline is the middle of the em square.
     */
    Middle = "middle",
    /**
     * The text baseline is the normal alphabetic baseline.
     */
    Alphabetic = "alphabetic",
    /**
     * The text baseline is the ideographic baseline; this is the bottom of
     * the body of the characters, if the main body of characters protrudes
     * beneath the alphabetic baseline.  Currently unsupported; this will
     * act like alphabetic.
     */
    Ideographic = "ideographic",
    /**
     * The text baseline is the bottom of the bounding box.  This differs
     * from the ideographic baseline in that the ideographic baseline
     * doesn't consider descenders.
     */
    Bottom = "bottom"
}
/**
 * Enum representing the different possible font styles
 */
export declare enum FontStyle {
    Normal = "normal",
    Italic = "italic",
    Oblique = "oblique"
}
/**
 * Enum representing the text direction, useful for other languages, or writing text in reverse
 */
export declare enum Direction {
    LeftToRight = "ltr",
    RightToLeft = "rtl"
}
/**
 * Font rendering option
 */
export interface FontOptions {
    /**
     * Optionally the size of the font in the specified {@apilink FontUnit} by default 10.
     */
    size?: number;
    /**
     * Optionally specify unit to measure fonts in, by default Pixels
     */
    unit?: FontUnit;
    /**
     * Optionally specify the font family, by default 'sans-serif'
     */
    family?: string;
    /**
     * Optionally specify the font style, by default Normal
     */
    style?: FontStyle;
    /**
     * Optionally set whether the font is bold, by default false
     */
    bold?: boolean;
    /**
     * Optionally specify the text align, by default Left
     */
    textAlign?: TextAlign;
    /**
     * Optionally specify the text base align, by default Alphabetic
     */
    baseAlign?: BaseAlign;
    /**
     * Optionally specify the text direction, by default LeftToRight
     */
    direction?: Direction;
    /**
     * Optionally override the text line height in pixels, useful for multiline text. If unset will use default.
     */
    lineHeight?: number | undefined;
    /**
     * Optionally specify the quality of the text bitmap, it is a multiplier on the size size, by default 2.
     * Higher quality text has a higher memory impact
     */
    quality?: number;
    /**
     * Optionally specify a text shadow, by default none is specified
     */
    shadow?: {
        blur?: number;
        offset?: Vector;
        color?: Color;
    };
}
/**
 * @internal
 */
export interface FontRenderer {
    measureText(text: string): BoundingBox;
    render(ex: ExcaliburGraphicsContext, text: string, color: Color, x: number, y: number): void;
}