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.Light;
var theme = VisualTheme.Graphite();
var model = ScatterPositionedColorScaleRecipe.Create("positioned-color-scale", mode);
var context = new VisualRenderContext(
    new VisualLayoutOptions(new VisualSize(800, 440)), theme, mode,
    new VisualFrame("Processing time by workload", "Absolute color anchors use uneven numeric intervals", 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());

/// <summary>Maps observed temperatures to explicitly positioned color stops.</summary>
public static class ScatterPositionedColorScaleRecipe {
    /// <summary>Creates the selected example without choosing a renderer or export backend.</summary>
    public static Chart Create(string variant = "positioned-color-scale", VisualThemeMode mode = VisualThemeMode.Light) {
        if (variant is not ("positioned-color-scale" or "compact-positioned-color-scale")) throw new ArgumentOutOfRangeException(nameof(variant));
        return PositionedColorScale(mode).WithValueFormat(ChartValueFormat.Number("0.##", CultureInfo.InvariantCulture));
    }

    private static Chart PositionedColorScale(VisualThemeMode mode) {
        var colors = VisualTheme.Graphite().Resolve(mode);
        var temperatures = new double?[] { -30, -20, -3, 0, 2.5, 5, 10, 22.5, 40, 55, null, null };
        var minutes = new[] { 24d, 36, 45, 20, 32, 50, 28, 41, 18, 35, 22, 48 };
        var recorded = ChartSeries.CreateScatter(new ChartSeriesId("recorded-batches"), "Recorded batches", temperatures.Select((value, index) =>
            new ChartPoint((index + 1) * 8, minutes[index]).WithColorValue(value)));
        recorded.WithColorScale(TemperatureScale().WithNoDataColor(colors.Border));
        return NumericAxes().ConfigureLabels(labels => { labels.Color = "Temperature (°C)"; labels.NoData = "Not sampled"; }).AddSeries(recorded);
    }

    private static Chart NumericAxes() => Chart.Create().WithXAxis("Batch size (items)").WithYAxis("Processing time (minutes)")
        .WithXAxisBounds(0, 100).WithYAxisBounds(0, 60).WithDataLabels(false);

    private static ChartColorScale TemperatureScale() => ChartColorScale.Diverging(new[] {
        new ChartColorStop(-20, ChartColor.FromHex("#2166AC")), new ChartColorStop(-3, ChartColor.FromHex("#67A9CF"))
    }, new ChartColorStop(0, ChartColor.FromHex("#D1D5DB")), new[] {
        new ChartColorStop(5, ChartColor.FromHex("#D9A441")), new ChartColorStop(40, ChartColor.FromHex("#B2182B"))
    }).WithLabels("Cold", "Freezing", "Warm");
}