#region Setup
using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Linq;
using ChartForgeX.Core;
using ChartForgeX.Primitives;
using ChartForgeX.Rendering;
using ChartForgeX.Themes;
using ChartForgeX.Topology;
using ChartForgeX.Typography;
using ChartForgeX.VisualArtifacts;
using ChartForgeX.VisualBlocks;

var mode = VisualThemeMode.Dark;
var theme = VisualTheme.Graphite();
var model = DonutRecipe.Create("compact", mode);
var context = new VisualRenderContext(
    new VisualLayoutOptions(new VisualSize(360, 360)), theme, mode,
    new VisualFrame("Services contributing to revenue", "", showLegend: null, showSurface: false));
var prepared = model.Prepare(context);
File.WriteAllText("visual.svg", prepared.ToSvg());
File.WriteAllBytes("visual.png", prepared.ToPng());
File.WriteAllText("visual.html", prepared.ToArtifact("example", VisualArtifactKind.Chart).ToHtmlPage());
#endregion

/// <summary>Service revenue with optional slice labels and a two-line center caption.</summary>
public static class DonutRecipe {
    /// <summary>Creates service revenue; the options variant adds labels, slice treatments and center text.</summary>
    public static Chart Create(string variant = "wide", VisualThemeMode mode = VisualThemeMode.Light) {
        if (variant is not ("wide" or "compact" or "sparse" or "options" or "compact-options"))
            throw new ArgumentOutOfRangeException(nameof(variant));
        var revenue = new ChartSeries(new ChartSeriesId("revenue"), "Revenue", ChartSeriesKind.Donut, Observations(variant));
        var chart = Chart.Create().WithXLabels("Subscriptions", "Consulting", "Support", "Licenses", "Training", "Other")
            .AddSeries(revenue);
        if (variant == "options") {
            chart.WithDataLabels().WithPieSliceLabelContent(ChartPieSliceLabelContent.Label).WithDonutCenterText("1,000", "Revenue (k)");
            revenue.WithPointSliceOffset(0, .12).WithPointFillPattern(1, ChartFillPattern.Crosshatch);
        }
        return chart;
    }

    // Revenue in thousands; the full set totals 1,000, so every share reads with the same one-decimal precision.
    private static readonly double[] Revenue = { 312, 241, 187, 133, 79, 48 };

    private static ChartPoint[] Observations(string variant) => variant == "sparse"
        ? new[] { 1, 3, 6 }.Select(index => new ChartPoint(index, 20 + index * 7 % 29)).ToArray()
        : Revenue.Select((value, index) => new ChartPoint(index + 1, value)).ToArray();
}