html2canvas/src/css/types/image.ts

118 lines
3.6 KiB
TypeScript

import {CSSValue} from '../syntax/parser';
import {TokenType} from '../syntax/tokenizer';
import {Color} from './color';
import {linearGradient} from './functions/linear-gradient';
import {prefixLinearGradient} from './functions/-prefix-linear-gradient';
import {ITypeDescriptor} from '../ITypeDescriptor';
import {CacheStorage} from '../../core/cache-storage';
import {LengthPercentage} from './length-percentage';
import {webkitGradient} from './functions/-webkit-gradient';
import {radialGradient} from './functions/radial-gradient';
import {prefixRadialGradient} from './functions/-prefix-radial-gradient';
export enum CSSImageType {
URL,
LINEAR_GRADIENT,
RADIAL_GRADIENT
}
export const isLinearGradient = (background: ICSSImage): background is CSSLinearGradientImage => {
return background.type === CSSImageType.LINEAR_GRADIENT;
};
export const isRadialGradient = (background: ICSSImage): background is CSSRadialGradientImage => {
return background.type === CSSImageType.RADIAL_GRADIENT;
};
export interface UnprocessedGradientColorStop {
color: Color;
stop: LengthPercentage | null;
}
export interface GradientColorStop {
color: Color;
stop: number;
}
export interface ICSSImage {
type: CSSImageType;
}
export interface CSSURLImage extends ICSSImage {
url: string;
type: CSSImageType.URL;
}
// interface ICSSGeneratedImage extends ICSSImage {}
export type GradientCorner = [LengthPercentage, LengthPercentage];
interface ICSSGradientImage extends ICSSImage {
stops: UnprocessedGradientColorStop[];
}
export interface CSSLinearGradientImage extends ICSSGradientImage {
angle: number | GradientCorner;
type: CSSImageType.LINEAR_GRADIENT;
}
export enum CSSRadialShape {
CIRCLE,
ELLIPSE
}
export enum CSSRadialExtent {
CLOSEST_SIDE,
FARTHEST_SIDE,
CLOSEST_CORNER,
FARTHEST_CORNER
}
export type CSSRadialSize = CSSRadialExtent | LengthPercentage[];
export interface CSSRadialGradientImage extends ICSSGradientImage {
type: CSSImageType.RADIAL_GRADIENT;
shape: CSSRadialShape;
size: CSSRadialSize;
position: LengthPercentage[];
}
export const image: ITypeDescriptor<ICSSImage> = {
name: 'image',
parse: (value: CSSValue): ICSSImage => {
if (value.type === TokenType.URL_TOKEN) {
const image: CSSURLImage = {url: value.value, type: CSSImageType.URL};
CacheStorage.getInstance().addImage(value.value);
return image;
}
if (value.type === TokenType.FUNCTION) {
const imageFunction = SUPPORTED_IMAGE_FUNCTIONS[value.name];
if (typeof imageFunction === 'undefined') {
throw new Error(`Attempting to parse an unsupported image function "${value.name}"`);
}
return imageFunction(value.values);
}
throw new Error(`Unsupported image type`);
}
};
export function isSupportedImage(value: CSSValue): boolean {
return value.type !== TokenType.FUNCTION || !!SUPPORTED_IMAGE_FUNCTIONS[value.name];
}
const SUPPORTED_IMAGE_FUNCTIONS: Record<string, (args: CSSValue[]) => ICSSImage> = {
'linear-gradient': linearGradient,
'-moz-linear-gradient': prefixLinearGradient,
'-ms-linear-gradient': prefixLinearGradient,
'-o-linear-gradient': prefixLinearGradient,
'-webkit-linear-gradient': prefixLinearGradient,
'radial-gradient': radialGradient,
'-moz-radial-gradient': prefixRadialGradient,
'-ms-radial-gradient': prefixRadialGradient,
'-o-radial-gradient': prefixRadialGradient,
'-webkit-radial-gradient': prefixRadialGradient,
'-webkit-gradient': webkitGradient
};