@devexperts/dxcharts-lite
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JavaScript
/*
* Copyright (C) 2019 - 2025 Devexperts Solutions IE Limited
* This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
* If a copy of the MPL was not distributed with this file, You can obtain one at https://mozilla.org/MPL/2.0/.
*/
import { typedEntries_UNSAFE } from '../../../utils/object.utils';
import { timeFormatMatcherFactory } from './parser/time-formats-matchers.functions';
import { parseTimeFormatsFromKey } from './parser/time-formats-parser.functions';
import { validateParsedTimeFormat } from './parser/time-formats-validators.functions';
import { getWeightFromTimeFormat } from './x-axis-weights.functions';
/**
* Returns the weight for a given date.
* Under the hood compares given date and previous date, to prevent generating the same label twice.
* It loops through the record of `weight` and corresponding {@link TimeFormatMatcher} pair, and tests the given date, if all the
* conditions are true, and it match some matcher, the weight returned for the given date.
* @see
* Weights order matters!
* @see
* returns `null` if date doesn't match any condition
*/
const getWeightByDate = (currentDate, previousDate, sortedWeights) => {
var _a, _b;
for (const [weight, timeMatcher] of sortedWeights) {
if (timeMatcher(currentDate, previousDate)) {
return weight;
}
}
// if date doesn't match any condition get the lowest weight
return (_b = (_a = sortedWeights[sortedWeights.length - 1]) === null || _a === void 0 ? void 0 : _a[0]) !== null && _b !== void 0 ? _b : 0;
};
/**
* Transforms {@link VisualCandle} to {@link WeightedPoint}
*/
export function mapCandlesToWeightedPoints(visualCandles, sortedWeights, tzOffset) {
const result = new Array(visualCandles.length);
// assume that candles` timestamp before the first visual candle is unreachable
let prevDate = tzOffset(0);
for (let i = 0; i < visualCandles.length; i++) {
const currentCandle = visualCandles[i];
// calculate timstamp to Date in acordance with provided timezone and time
const currentDate = tzOffset(currentCandle.candle.timestamp);
const currentWeightedPoint = {
weight: getWeightByDate(currentDate, prevDate, sortedWeights),
};
result[i] = currentWeightedPoint;
prevDate = currentDate;
}
return result;
}
/**
* Generates two maps for a given config.
* 1st map is { [weight]: [format] } to control which format should be used for a given weight;
* 2nd map is { [weight]: [Matcher] } to test a date for a match for a given weight;
*
* @example
* const config: Record<TimeFormatWithDuration, string> = {
* 'day_15': 'dd.MM',
* 'month_7!': 'MMM'
* }
* const { map1, map2 } = generateWeightsMapForConfig(config);
* // map1 = { 415: 'dd.MM', 607: 'MMM' };
* // map2 = { 415: DayMatcher, 607: MonthMatcher }
*/
export const generateWeightsMapForConfig = (config) => {
const weightToTimeFormatsDict = {};
const weightToTimeFormatMatcherDict = {};
typedEntries_UNSAFE(config).forEach(([item, format]) => {
const timeFormat = parseTimeFormatsFromKey(item);
const validFormat = timeFormat === null ? false : validateParsedTimeFormat(timeFormat);
if (timeFormat && validFormat) {
const weight = getWeightFromTimeFormat(timeFormat);
weightToTimeFormatsDict[weight] = format;
weightToTimeFormatMatcherDict[weight] = timeFormatMatcherFactory(timeFormat);
}
});
return { weightToTimeFormatsDict, weightToTimeFormatMatcherDict };
};