nagix/chartjs-plugin-style

'use strict';

import Chart from 'chart.js';
import StyleTooltip from '../core/core.styleTooltip';
import StyleBarController from '../controllers/controller.styleBar';
import StyleBubbleController from '../controllers/controller.styleBubble';
import StyleDoughnutController from '../controllers/controller.styleDoughnut';
import StyleHorizontalBarController from '../controllers/controller.styleHorizontalBar';
import StyleLineController from '../controllers/controller.styleLine';
import StylePolarAreaController from '../controllers/controller.stylePolarArea';
import StyleRadarController from '../controllers/controller.styleRadar';
import StyleLegendPlugin from './plugin.styleLegend';

var helpers = Chart.helpers;

// For Chart.js 2.7.1 backward compatibility
var layouts = Chart.layouts || Chart.layoutService;

var plugins = Chart.plugins;

var styleControllers = {
    bar: StyleBarController,
    bubble: StyleBubbleController,
    doughnut: StyleDoughnutController,
    horizontalBar: StyleHorizontalBarController,
    line: StyleLineController,
    polarArea: StylePolarAreaController,
    pie: StyleDoughnutController,
    radar: StyleRadarController,
    scatter: StyleLineController
};

// Ported from Chart.js 2.8.0. Modified for style controllers.
function buildOrUpdateControllers() {
    var me = this;
    var newControllers = [];

    helpers.each(me.data.datasets, function(dataset, datasetIndex) {
        var meta = me.getDatasetMeta(datasetIndex);
        var type = dataset.type || me.config.type;

        if (meta.type && meta.type !== type) {
            me.destroyDatasetMeta(datasetIndex);
            meta = me.getDatasetMeta(datasetIndex);
        }
        meta.type = type;

        if (meta.controller) {
            meta.controller.updateIndex(datasetIndex);
            meta.controller.linkScales();
        } else {
            var ControllerClass = styleControllers[meta.type];
            if (ControllerClass === undefined) {
                throw new Error('"' + meta.type + '" is not a chart type.');
            }

            meta.controller = new ControllerClass(me, datasetIndex);
            newControllers.push(meta.controller);
        }
    }, me);

    return newControllers;
}

// Ported from Chart.js 2.8.0. Modified for style tooltip.
function initToolTip() {
    var me = this;
    me.tooltip = new StyleTooltip({
        _chart: me,
        _chartInstance: me, // deprecated, backward compatibility
        _data: me.data,
        _options: me.options.tooltips
    }, me);
}

var descriptors = plugins.descriptors;

plugins.descriptors = function(chart) {
    var style = chart._style;

    // Replace legend plugin with style legend plugin
    if (style) {
        // chart._plugins for Chart.js 2.7.1 backward compatibility
        var cache = chart.$plugins || chart._plugins || (chart.$plugins = chart._plugins = {});
        if (cache.id === this._cacheId) {
            return cache.descriptors;
        }

        var p = this._plugins;
        var result;

        this._plugins = p.map(function(plugin) {
            if (plugin.id === 'legend') {
                return StyleLegendPlugin;
            }
            return plugin;
        });
    }

    result = descriptors.apply(this, arguments);

    if (style) {
        this._plugins = p;
    }

    return result;
};

export default {
    id: 'style',

    beforeInit: function(chart) {
        chart._style = {};

        chart.buildOrUpdateControllers = buildOrUpdateControllers;
        chart.initToolTip = initToolTip;

        // Remove the existing legend if exists
        if (chart.legend) {
            layouts.removeBox(chart, chart.legend);
            delete chart.legend;
        }

        // Invalidate plugin cache and create new one
        delete chart.$plugins;
        // For Chart.js 2.7.1 backward compatibility
        delete chart._plugins;
        plugins.descriptors(chart);
    }
};