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/*
* 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 * as textContain from 'zrender/src/contain/text';
import Axis from '../Axis';
import {makeInner} from '../../util/model';

var inner = makeInner();

function AngleAxis(scale, angleExtent) {

    angleExtent = angleExtent || [0, 360];

    Axis.call(this, 'angle', scale, angleExtent);

    /**
     * Axis type
     *  - 'category'
     *  - 'value'
     *  - 'time'
     *  - 'log'
     * @type {string}
     */
    this.type = 'category';
}

AngleAxis.prototype = {

    constructor: AngleAxis,

    /**
     * @override
     */
    pointToData: function (point, clamp) {
        return this.polar.pointToData(point, clamp)[this.dim === 'radius' ? 0 : 1];
    },

    dataToAngle: Axis.prototype.dataToCoord,

    angleToData: Axis.prototype.coordToData,

    /**
     * Only be called in category axis.
     * Angle axis uses text height to decide interval
     *
     * @override
     * @return {number} Auto interval for cateogry axis tick and label
     */
    calculateCategoryInterval: function () {
        var axis = this;
        var labelModel = axis.getLabelModel();

        var ordinalScale = axis.scale;
        var ordinalExtent = ordinalScale.getExtent();
        // Providing this method is for optimization:
        // avoid generating a long array by `getTicks`
        // in large category data case.
        var tickCount = ordinalScale.count();

        if (ordinalExtent[1] - ordinalExtent[0] < 1) {
            return 0;
        }

        var tickValue = ordinalExtent[0];
        var unitSpan = axis.dataToCoord(tickValue + 1) - axis.dataToCoord(tickValue);
        var unitH = Math.abs(unitSpan);

        // Not precise, just use height as text width
        // and each distance from axis line yet.
        var rect = textContain.getBoundingRect(
            tickValue, labelModel.getFont(), 'center', 'top'
        );
        var maxH = Math.max(rect.height, 7);

        var dh = maxH / unitH;
        // 0/0 is NaN, 1/0 is Infinity.
        isNaN(dh) && (dh = Infinity);
        var interval = Math.max(0, Math.floor(dh));

        var cache = inner(axis.model);
        var lastAutoInterval = cache.lastAutoInterval;
        var lastTickCount = cache.lastTickCount;

        // Use cache to keep interval stable while moving zoom window,
        // otherwise the calculated interval might jitter when the zoom
        // window size is close to the interval-changing size.
        if (lastAutoInterval != null
            && lastTickCount != null
            && Math.abs(lastAutoInterval - interval) <= 1
            && Math.abs(lastTickCount - tickCount) <= 1
            // Always choose the bigger one, otherwise the critical
            // point is not the same when zooming in or zooming out.
            && lastAutoInterval > interval
        ) {
            interval = lastAutoInterval;
        }
        // Only update cache if cache not used, otherwise the
        // changing of interval is too insensitive.
        else {
            cache.lastTickCount = tickCount;
            cache.lastAutoInterval = interval;
        }

        return interval;
    }
};

zrUtil.inherits(AngleAxis, Axis);

export default AngleAxis;