using DevExpress.Spreadsheet;
using DevExpress.Spreadsheet.Charts;
using DevExpress.XtraSpreadsheet.Services;
using DevExpress.Office.Services;
using System.Drawing;

Stream GenerateDocumentWithChart(Stream chartTemplateInputStream, ChartOptions options, DocumentFormat outputFormat) {
    using var workbook = new Workbook();
    var worksheet = workbook.Worksheets.First();
    worksheet.Name = "Chart Data";

    // Specify chart data
    var months = new[] { "January", "February", "March", "April", "May", "June" };
    var units = new[] { 50, 100, 30, 104, 87, 150 };
    var transactions = new[] { 900, 3000, 1200, 7000, 5100, 7500 };

    worksheet["A1"].Value = "Month";
    worksheet["B1"].Value = "Units Sold";
    worksheet["C1"].Value = "Total Transactions";

    for(int i = 0; i < months.Length; i++) {
        int row = i + 2;
        worksheet[$"A{row}"].Value = months[i];
        worksheet[$"B{row}"].Value = units[i];
        worksheet[$"C{row}"].Value = transactions[i];
    }

    // Apply formatting to chart data cells
    var headerRange = worksheet["A1:C1"];
    headerRange.Font.Bold = true;
    headerRange.Fill.BackgroundColor = Color.LightGray;

    var dataRange = worksheet.GetDataRange();
    dataRange.Borders.SetOutsideBorders(Color.Black, BorderLineStyle.Thin);

    worksheet.Columns.AutoFit(0, 2);

    // Create chart
    ChartObject chart;

    if(options.CreateChartSheet) {
        var chartSheet = workbook.ChartSheets.Add(ChartType.ColumnClustered, dataRange);
        chartSheet.Name = "Chart Sheet";
        chart = chartSheet.Chart;
    } else {
        var chartInstance = worksheet.Charts.Add(ChartType.ColumnClustered, dataRange);
        // For an embedded chart, set the location and size
        chartInstance.TopLeftCell = worksheet.Cells["F1"];
        chartInstance.BottomRightCell = worksheet.Cells["R30"];
        chart = chartInstance;
    }

    // Configure secondary series
    chart.Series[1].ChangeType(DevExpress.Spreadsheet.Charts.ChartType.LineMarker);
    chart.Series[1].AxisGroup = AxisGroup.Secondary;

    // Apply chart formatting
    chart.Title.SetValue("Example Chart");
    chart.Title.Visible = true;
    chart.Title.Font.Color = Color.FromArgb(0x1D, 0x2B, 0x64);

    chart.Legend.Visible = options.ShowLegend;
    chart.Legend.Position = options.LegendPosition;

    chart.Views[0].DataLabels.ShowValue = options.ShowDataLabels;

    // Apply primary axis settings
    if(chart.PrimaryAxes.Count >= 2) {
        var xAxis = chart.PrimaryAxes[0];
        var yAxis = chart.PrimaryAxes[1];

        xAxis.Title.SetValue("Months");
        yAxis.Title.SetValue("Units");

        xAxis.Title.Visible = yAxis.Title.Visible = options.ShowAxisTitles;
        xAxis.MajorGridlines.Visible = yAxis.MajorGridlines.Visible = options.ShowGridLines;
    }

    // Add trendline for the first series
    if(options.ShowTrendline) {
        var series = chart.Series[0];
        var trendline = series.Trendlines.Add(ChartTrendlineType.Linear);

        trendline.CustomName = $"{series.SeriesName.PlainText} Trend";
        trendline.Outline.SetSolidFill(Color.Red);
    }

    // Load chart template
    if(options.LoadFromTemplate) {
        chart.LoadTemplate(chartTemplateInputStream);
    }

    // Prepare output stream
    var outputStream = new MemoryStream();

    // Save the document
    workbook.SaveDocument(outputStream, outputFormat);

    outputStream.Position = 0;
    return outputStream;
}

public class ChartOptions {
    public bool LoadFromTemplate { get; set; }
    public bool CreateChartSheet { get; set; }
    public bool ShowTrendline { get; set; }
    public bool ShowDataLabels { get; set; }
    public bool ShowAxisTitles { get; set; }
    public bool ShowGridLines { get; set; }
    public bool ShowLegend { get; set; }
    public LegendPosition LegendPosition { get; set; } = LegendPosition.Right;
}