src/component/tooltip/helper.ts

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements.  See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership.  The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License.  You may obtain a copy of the License at
*
*   http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied.  See the License for the
* specific language governing permissions and limitations
* under the License.
*/

import { TooltipOption } from './TooltipModel';
import Model from '../../model/Model';
import { toCamelCase } from '../../util/format';
import env from 'zrender/src/core/env';

/* global document */

export function shouldTooltipConfine(tooltipModel: Model<TooltipOption>): boolean {
    const confineOption = tooltipModel.get('confine');
    return confineOption != null
        ? !!confineOption
        // In richText mode, the outside part can not be visible.
        : tooltipModel.get('renderMode') === 'richText';
}

function testStyle(styleProps: string[]): string | undefined {
    if (!env.domSupported) {
        return;
    }
    const style = document.documentElement.style;
    for (let i = 0, len = styleProps.length; i < len; i++) {
        if (styleProps[i] in style) {
            return styleProps[i];
        }
    }
}

export const TRANSFORM_VENDOR = testStyle(
    ['transform', 'webkitTransform', 'OTransform', 'MozTransform', 'msTransform']
);

export const TRANSITION_VENDOR = testStyle(
    ['webkitTransition', 'transition', 'OTransition', 'MozTransition', 'msTransition']
);

export function toCSSVendorPrefix(styleVendor: string, styleProp: string) {
    if (!styleVendor) {
        return styleProp;
    }
    styleProp = toCamelCase(styleProp, true);
    const idx = styleVendor.indexOf(styleProp);
    styleVendor = idx === -1
        ? styleProp
        : `-${styleVendor.slice(0, idx)}-${styleProp}`;
    return styleVendor.toLowerCase();
}

export function getComputedStyle(el: HTMLElement, style?: string) {
    const stl = (el as any).currentStyle
        || (document.defaultView && document.defaultView.getComputedStyle(el));
    return stl
        ? style ? stl[style] : stl
        : null;
}