src/component/visualMap/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 * as zrUtil from 'zrender/src/core/util';
import {getLayoutRect} from '../../util/layout';
import VisualMapModel from './VisualMapModel';
import ExtensionAPI from '../../core/ExtensionAPI';
import { Payload } from '../../util/types';

const paramsSet = [
    ['left', 'right', 'width'],
    ['top', 'bottom', 'height']
] as const;
export type ItemHorizontalAlign = typeof paramsSet[0][number];
export type ItemVerticalAlign = typeof paramsSet[1][number];
export type ItemAlign = ItemVerticalAlign | ItemHorizontalAlign;

/**
 * @param visualMapModel
 * @param api
 * @param itemSize always [short, long]
 * @return {string} 'left' or 'right' or 'top' or 'bottom'
 */
export function getItemAlign(
    visualMapModel: VisualMapModel,
    api: ExtensionAPI,
    itemSize: number[]
): ItemAlign {
    const modelOption = visualMapModel.option;
    const itemAlign = modelOption.align;

    if (itemAlign != null && itemAlign !== 'auto') {
        return itemAlign as ItemAlign;
    }

    // Auto decision align.
    const ecSize = {width: api.getWidth(), height: api.getHeight()};
    const realIndex = modelOption.orient === 'horizontal' ? 1 : 0;

    const reals = paramsSet[realIndex];
    const fakeValue = [0, null, 10];

    const layoutInput = {} as Record<ItemAlign, number | string>;
    for (let i = 0; i < 3; i++) {
        layoutInput[paramsSet[1 - realIndex][i]] = fakeValue[i];
        layoutInput[reals[i]] = i === 2 ? itemSize[0] : modelOption[reals[i]];
    }

    const rParam = ([['x', 'width', 3], ['y', 'height', 0]] as const)[realIndex];
    const rect = getLayoutRect(layoutInput, ecSize, modelOption.padding);

    return reals[
        (rect.margin[rParam[2]] || 0) + rect[rParam[0]] + rect[rParam[1]] * 0.5
            < ecSize[rParam[1]] * 0.5 ? 0 : 1
    ];
}

/**
 * Prepare dataIndex for outside usage, where dataIndex means rawIndex, and
 * dataIndexInside means filtered index.
 */

 // TODO: TYPE more specified payload types.
export function makeHighDownBatch(batch: Payload['batch'], visualMapModel: VisualMapModel): Payload['batch'] {
    zrUtil.each(batch || [], function (batchItem) {
        if (batchItem.dataIndex != null) {
            batchItem.dataIndexInside = batchItem.dataIndex;
            batchItem.dataIndex = null;
        }
        batchItem.highlightKey = 'visualMap' + (visualMapModel ? visualMapModel.componentIndex : '');
    });
    return batch;
}