[IMP] chart: support import/export of dataset trendlines

This commit introduces the ability to import and export trendlines
associated with datasets in chart configurations.

Task: 4319957

src/helpers/figures/charts/bar_chart.ts

@@ -17,7 +17,6 @@ import {
   ChartCreationContext,
   CustomizedDataSet,
   DataSet,
-  DatasetDesign,
   ExcelChartDataset,
   ExcelChartDefinition,
 } from "../../../types/chart/chart";
@@ -62,7 +61,7 @@ export class BarChart extends AbstractChart {
   readonly aggregated?: boolean;
   readonly type = "bar";
   readonly dataSetsHaveTitle: boolean;
-  readonly dataSetDesign?: DatasetDesign[];
+  readonly customDatasets?: CustomizedDataSet[];
   readonly axesDesign?: AxesDesign;
   readonly horizontal?: boolean;
   readonly showValues?: boolean;
@@ -81,7 +80,7 @@ export class BarChart extends AbstractChart {
     this.stacked = definition.stacked;
     this.aggregated = definition.aggregated;
     this.dataSetsHaveTitle = definition.dataSetsHaveTitle;
-    this.dataSetDesign = definition.dataSets;
+    this.customDatasets = definition.dataSets;
     this.axesDesign = definition.axesDesign;
     this.horizontal = definition.horizontal;
     this.showValues = definition.showValues;
@@ -121,7 +120,7 @@ export class BarChart extends AbstractChart {
     const range: CustomizedDataSet[] = [];
     for (const [i, dataSet] of this.dataSets.entries()) {
       range.push({
-        ...this.dataSetDesign?.[i],
+        ...this.customDatasets?.[i],
         dataRange: this.getters.getRangeString(dataSet.dataRange, this.sheetId),
       });
     }
@@ -162,7 +161,7 @@ export class BarChart extends AbstractChart {
     const ranges: CustomizedDataSet[] = [];
     for (const [i, dataSet] of dataSets.entries()) {
       ranges.push({
-        ...this.dataSetDesign?.[i],
+        ...this.customDatasets?.[i],
         dataRange: this.getters.getRangeString(dataSet.dataRange, targetSheetId || this.sheetId),
       });
     }
@@ -188,7 +187,7 @@ export class BarChart extends AbstractChart {
     // Excel does not support aggregating labels
     if (this.aggregated) return undefined;
     const dataSets: ExcelChartDataset[] = this.dataSets
-      .map((ds: DataSet) => toExcelDataset(this.getters, ds))
+      .map((ds: DataSet, i: number) => toExcelDataset(this.getters, ds, this.customDatasets?.[i]))
       .filter((ds) => ds.range !== "" && ds.range !== CellErrorType.InvalidReference);
     const labelRange = toExcelLabelRange(
       this.getters,

src/helpers/figures/charts/chart_common.ts

@@ -24,9 +24,11 @@ import {
   DataSet,
   DatasetValues,
   ExcelChartDataset,
+  ExcelChartTrendConfiguration,
   GenericDefinition,
 } from "../../../types/chart/chart";
 import { CellErrorType } from "../../../types/errors";
+import { CHART_TRENDLINE_TYPE_CONVERSION_MAP_REVERSE } from "../../../xlsx/conversion";
 import { ColorGenerator, relativeLuminance } from "../../color";
 import { formatValue } from "../../format/format";
 import { isDefined, largeMax } from "../../misc";
@@ -246,7 +248,11 @@ function createDataSet(
 /**
  * Transform a dataSet to a ExcelDataSet
  */
-export function toExcelDataset(getters: CoreGetters, ds: DataSet): ExcelChartDataset {
+export function toExcelDataset(
+  getters: CoreGetters,
+  ds: DataSet,
+  customDs?: CustomizedDataSet
+): ExcelChartDataset {
   const labelZone = ds.labelCell?.zone;
   let dataZone = ds.dataRange.zone;
   if (labelZone) {
@@ -272,6 +278,24 @@ export function toExcelDataset(getters: CoreGetters, ds: DataSet): ExcelChartDat
     };
   }
 
+  let trend: ExcelChartTrendConfiguration | undefined = undefined;
+  if (customDs?.trend?.type) {
+    trend = {
+      type: CHART_TRENDLINE_TYPE_CONVERSION_MAP_REVERSE[customDs.trend.type],
+      order: customDs?.trend?.order,
+      color: customDs?.trend?.color,
+      window: customDs?.trend?.window,
+    };
+  }
+  if (trend) {
+    return {
+      label,
+      range: getters.getRangeString(dataRange, "forceSheetReference", { useFixedReference: true }),
+      backgroundColor: ds.backgroundColor,
+      rightYAxis: ds.rightYAxis,
+      trend,
+    };
+  }
   return {
     label,
     range: getters.getRangeString(dataRange, "forceSheetReference", { useFixedReference: true }),

src/helpers/figures/charts/combo_chart.ts

@@ -156,7 +156,7 @@ export class ComboChart extends AbstractChart {
       return undefined;
     }
     const dataSets: ExcelChartDataset[] = this.dataSets
-      .map((ds: DataSet) => toExcelDataset(this.getters, ds))
+      .map((ds: DataSet, i: number) => toExcelDataset(this.getters, ds, this.dataSetDesign?.[i]))
       .filter((ds) => ds.range !== "" && ds.range !== CellErrorType.InvalidReference);
     const labelRange = toExcelLabelRange(
       this.getters,

src/helpers/figures/charts/line_chart.ts

@@ -17,7 +17,6 @@ import {
   ChartJSRuntime,
   CustomizedDataSet,
   DataSet,
-  DatasetDesign,
   ExcelChartDataset,
   ExcelChartDefinition,
 } from "../../../types/chart/chart";
@@ -65,7 +64,7 @@ export class LineChart extends AbstractChart {
   readonly type = "line";
   readonly dataSetsHaveTitle: boolean;
   readonly cumulative: boolean;
-  readonly dataSetDesign?: DatasetDesign[];
+  readonly customDatasets?: CustomizedDataSet[];
   readonly axesDesign?: AxesDesign;
   readonly fillArea?: boolean;
   readonly showValues?: boolean;
@@ -86,7 +85,7 @@ export class LineChart extends AbstractChart {
     this.aggregated = definition.aggregated;
     this.dataSetsHaveTitle = definition.dataSetsHaveTitle;
     this.cumulative = definition.cumulative;
-    this.dataSetDesign = definition.dataSets;
+    this.customDatasets = definition.dataSets;
     this.axesDesign = definition.axesDesign;
     this.fillArea = definition.fillArea;
     this.showValues = definition.showValues;
@@ -137,7 +136,7 @@ export class LineChart extends AbstractChart {
     const ranges: CustomizedDataSet[] = [];
     for (const [i, dataSet] of dataSets.entries()) {
       ranges.push({
-        ...this.dataSetDesign?.[i],
+        ...this.customDatasets?.[i],
         dataRange: this.getters.getRangeString(dataSet.dataRange, targetSheetId || this.sheetId),
       });
     }
@@ -165,7 +164,7 @@ export class LineChart extends AbstractChart {
     const range: CustomizedDataSet[] = [];
     for (const [i, dataSet] of this.dataSets.entries()) {
       range.push({
-        ...this.dataSetDesign?.[i],
+        ...this.customDatasets?.[i],
         dataRange: this.getters.getRangeString(dataSet.dataRange, this.sheetId),
       });
     }
@@ -196,7 +195,7 @@ export class LineChart extends AbstractChart {
     // Excel does not support aggregating labels
     if (this.aggregated) return undefined;
     const dataSets: ExcelChartDataset[] = this.dataSets
-      .map((ds: DataSet) => toExcelDataset(this.getters, ds))
+      .map((ds: DataSet, i: number) => toExcelDataset(this.getters, ds, this.customDatasets?.[i]))
       .filter((ds) => ds.range !== "" && ds.range !== CellErrorType.InvalidReference);
     const labelRange = toExcelLabelRange(
       this.getters,

src/helpers/figures/charts/scatter_chart.ts

@@ -184,7 +184,7 @@ export class ScatterChart extends AbstractChart {
       return undefined;
     }
     const dataSets: ExcelChartDataset[] = this.dataSets
-      .map((ds: DataSet) => toExcelDataset(this.getters, ds))
+      .map((ds: DataSet, i: number) => toExcelDataset(this.getters, ds))
       .filter((ds) => ds.range !== "");
     const labelRange = toExcelLabelRange(
       this.getters,

src/types/chart/chart.ts

@@ -118,8 +118,18 @@ export interface ExcelChartDataset {
   readonly range: string;
   readonly backgroundColor?: Color;
   readonly rightYAxis?: boolean;
+  readonly trend?: ExcelChartTrendConfiguration;
 }
 
+export interface ExcelChartTrendConfiguration {
+  readonly type?: ExcelTrendlineType;
+  readonly order?: number;
+  readonly color?: Color;
+  readonly window?: number;
+}
+
+export type ExcelTrendlineType = "poly" | "exp" | "log" | "movingAvg" | "linear";
+
 export type ExcelChartType = "line" | "bar" | "pie" | "combo" | "scatter" | "radar";
 
 export interface ExcelChartDefinition {

src/xlsx/conversion/conversion_maps.ts

@@ -208,6 +208,20 @@ export const CHART_TYPE_CONVERSION_MAP: Record<XLSXChartType, ExcelChartType | u
   comboChart: "combo",
 };
 
+export const CHART_TRENDLINE_TYPE_CONVERSION_MAP = {
+  exp: "exponential",
+  log: "logarithmic",
+  poly: "polynomial",
+  movingAvg: "trailingMovingAverage",
+} as const;
+
+export const CHART_TRENDLINE_TYPE_CONVERSION_MAP_REVERSE = {
+  exponential: "exp",
+  logarithmic: "log",
+  polynomial: "poly",
+  trailingMovingAverage: "movingAvg",
+} as const;
+
 /** Conversion map for the SUBTOTAL(index, formula) function in xlsx, index <=> actual function*/
 export const SUBTOTAL_FUNCTION_CONVERSION_MAP: Record<number, string> = {
   "1": "AVERAGE",

src/xlsx/conversion/figure_conversion.ts

@@ -5,12 +5,20 @@ import {
   toUnboundedZone,
   zoneToXc,
 } from "../../helpers";
-import { ChartDefinition, ExcelChartDefinition, FigureData } from "../../types";
+import {
+  ChartDefinition,
+  ExcelChartDefinition,
+  ExcelChartTrendConfiguration,
+  ExcelTrendlineType,
+  FigureData,
+  TrendConfiguration,
+} from "../../types";
 import { ExcelImage } from "../../types/image";
 import { XLSXFigure, XLSXWorksheet } from "../../types/xlsx";
 import { convertEMUToDotValue, getColPosition, getRowPosition } from "../helpers/content_helpers";
 import { XLSXFigureAnchor } from "./../../types/xlsx";
 import { convertColor } from "./color_conversion";
+import { CHART_TRENDLINE_TYPE_CONVERSION_MAP } from "./conversion_maps";
 
 export function convertFigures(sheetData: XLSXWorksheet): FigureData<any>[] {
   let id = 1;
@@ -84,6 +92,7 @@ function convertChartData(chartData: ExcelChartDefinition): ChartDefinition | un
       dataRange: convertExcelRangeToSheetXC(data.range, dataSetsHaveTitle),
       label,
       backgroundColor: data.backgroundColor,
+      trend: convertExcelTrenline(data.trend),
     };
   });
   // For doughnut charts, in chartJS first dataset = outer dataset, in excel first dataset = inner dataset
@@ -121,6 +130,30 @@ function convertExcelRangeToSheetXC(range: string, dataSetsHaveTitle: boolean):
   return getFullReference(sheetName, dataXC);
 }
 
+function convertExcelTrenline(
+  trend: ExcelChartTrendConfiguration | undefined
+): TrendConfiguration | undefined {
+  if (!trend) {
+    return undefined;
+  }
+  if (trend.type === "linear") {
+    return {
+      type: "polynomial",
+      order: 1,
+      color: trend.color,
+      window: trend.window,
+      display: true,
+    };
+  }
+  return {
+    type: CHART_TRENDLINE_TYPE_CONVERSION_MAP[trend.type as ExcelTrendlineType],
+    order: trend.order,
+    color: trend.color,
+    window: trend.window,
+    display: true,
+  };
+}
+
 function getPositionFromAnchor(
   anchor: XLSXFigureAnchor,
   sheetData: XLSXWorksheet

src/xlsx/extraction/chart_extractor.ts

@@ -1,5 +1,10 @@
 import { toHex } from "../../helpers";
-import { ExcelChartDataset, ExcelChartDefinition } from "../../types";
+import {
+  ExcelChartDataset,
+  ExcelChartDefinition,
+  ExcelChartTrendConfiguration,
+  ExcelTrendlineType,
+} from "../../types";
 import { XLSXChartType, XLSX_CHART_TYPES } from "../../types/xlsx";
 import { CHART_TYPE_CONVERSION_MAP, DRAWING_LEGEND_POSITION_CONVERSION_MAP } from "../conversion";
 import { removeTagEscapedNamespaces } from "../helpers/xml_helpers";
@@ -139,13 +144,33 @@ export class XlsxChartExtractor extends XlsxBaseExtractor {
                 required: true,
               })!,
               backgroundColor: color ? `${toHex(color.asString())}` : undefined,
+              trend: this.extractChartTrendline(chartDataElement),
             };
           }
         );
       })
       .flat();
   }
 
+  private extractChartTrendline(
+    chartDataElement: Element
+  ): ExcelChartTrendConfiguration | undefined {
+    const trendlineElement = this.querySelector(chartDataElement, "c:trendline");
+    if (!trendlineElement) {
+      return undefined;
+    }
+    const trendlineType = this.extractChildAttr(trendlineElement, "c:trendlineType", "val");
+    const trendlineColor = this.extractChildAttr(trendlineElement, "a:solidFill a:srgbClr", "val");
+    const trendlineOrder = this.extractChildAttr(trendlineElement, "c:order", "val");
+    const trendlineWindow = this.extractChildAttr(trendlineElement, "c:period", "val");
+    return {
+      type: trendlineType ? (trendlineType.asString() as ExcelTrendlineType) : undefined,
+      order: trendlineOrder ? trendlineOrder.asNum() : undefined,
+      window: trendlineWindow ? trendlineWindow.asNum() : undefined,
+      color: trendlineColor ? `${toHex(trendlineColor.asString())}` : undefined,
+    };
+  }
+
   private extractScatterChartDatasets(chartElement: Element): ExcelChartDataset[] {
     return this.mapOnElements(
       { parent: chartElement, query: "c:ser" },