NativeScript/packages/core/ui/styling/background.android.ts

import { View } from '../core/view';
import { LinearGradient } from './linear-gradient';
import { ClipPathFunction } from './clip-path-function';
import { isDataURI, isFileOrResourcePath, RESOURCE_PREFIX, FILE_PREFIX } from '../../utils';
import { CSSValue, parse } from '../../css-value';
import { path, knownFolders } from '../../file-system';
export * from './background-common';

function fromBase64(source: string): android.graphics.Bitmap {
	const bytes = android.util.Base64.decode(source, android.util.Base64.DEFAULT);

	return android.graphics.BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
}

function fromGradient(gradient: LinearGradient): org.nativescript.widgets.LinearGradientDefinition {
	const colors = Array.create('int', gradient.colorStops.length);
	const stops = Array.create('float', gradient.colorStops.length);
	let hasStops = false;
	gradient.colorStops.forEach((stop, index) => {
		colors[index] = stop.color.android;
		if (stop.offset) {
			stops[index] = stop.offset.value;
			hasStops = true;
		}
	});

	const alpha = gradient.angle / (Math.PI * 2);
	const startX = Math.pow(Math.sin(Math.PI * (alpha + 0.75)), 2);
	const startY = Math.pow(Math.sin(Math.PI * (alpha + 0.5)), 2);
	const endX = Math.pow(Math.sin(Math.PI * (alpha + 0.25)), 2);
	const endY = Math.pow(Math.sin(Math.PI * alpha), 2);

	return new org.nativescript.widgets.LinearGradientDefinition(startX, startY, endX, endY, colors, hasStops ? stops : null);
}

const pattern = /url\(('|")(.*?)\1\)/;
export function refreshBorderDrawable(view: View, borderDrawable: org.nativescript.widgets.BorderDrawable) {
	const nativeView = <android.view.View>view.nativeViewProtected;
	const context = nativeView.getContext();

	const background = view.style.backgroundInternal;
	if (background) {
		const backgroundPositionParsedCSSValues = createNativeCSSValueArray(background.position);
		const backgroundSizeParsedCSSValues = createNativeCSSValueArray(background.size);
		const blackColor = -16777216; //android.graphics.Color.BLACK;

		let imageUri: string;
		if (background.image && typeof background.image === 'string' && background.image !== 'none') {
			imageUri = background.image;
			const match = imageUri.match(pattern);
			if (match && match[2]) {
				imageUri = match[2];
			}
		}

		let bitmap: android.graphics.Bitmap = null;
		if (isDataURI(imageUri)) {
			const base64Data = imageUri.split(',')[1];
			if (base64Data !== undefined) {
				bitmap = fromBase64(base64Data);
				imageUri = null;
			}
		} else if (isFileOrResourcePath(imageUri)) {
			if (imageUri.indexOf(RESOURCE_PREFIX) !== 0) {
				let fileName = imageUri;
				if (fileName.indexOf('~/') === 0) {
					fileName = path.join(knownFolders.currentApp().path, fileName.replace('~/', ''));
				}

				imageUri = FILE_PREFIX + fileName;
			}
		}

		let gradient: org.nativescript.widgets.LinearGradientDefinition = null;
		if (background.image && background.image instanceof LinearGradient) {
			gradient = fromGradient(background.image);
		}

		borderDrawable.refresh(
			background.borderTopColor ? background.borderTopColor.android : blackColor,
			background.borderRightColor ? background.borderRightColor.android : blackColor,
			background.borderBottomColor ? background.borderBottomColor.android : blackColor,
			background.borderLeftColor ? background.borderLeftColor.android : blackColor,

			background.borderTopWidth,
			background.borderRightWidth,
			background.borderBottomWidth,
			background.borderLeftWidth,

			background.borderTopLeftRadius,
			background.borderTopRightRadius,
			background.borderBottomRightRadius,
			background.borderBottomLeftRadius,

			background.clipPath instanceof ClipPathFunction ? background.clipPath.toString() : background.clipPath,

			background.color ? background.color.android : 0,
			imageUri,
			bitmap,
			gradient,
			context,
			background.repeat,
			background.position,
			backgroundPositionParsedCSSValues,
			background.size,
			backgroundSizeParsedCSSValues,
		);
		//console.log(`>>> ${borderDrawable.toDebugString()}`);
	}
}

function createNativeCSSValueArray(css: string): androidNative.Array<org.nativescript.widgets.CSSValue> {
	if (!css) {
		return null;
	}

	const cssValues = parse(css) as CSSValue[];
	const nativeArray = Array.create(org.nativescript.widgets.CSSValue, cssValues.length);
	for (let i = 0, length = cssValues.length; i < length; i++) {
		nativeArray[i] = new org.nativescript.widgets.CSSValue(cssValues[i].type, cssValues[i].string, cssValues[i].unit, cssValues[i].value);
	}

	return nativeArray;
}