using System.Drawing;
using System.Text.RegularExpressions;
using Pastel;

namespace Yuanshen.Common.Console;

public static class ConsoleTheme
{
    public static readonly Color GradientFrom = Color.FromArgb(0x7B, 0x2F, 0xF7);
    public static readonly Color GradientTo = Color.FromArgb(0xE0, 0x40, 0xFB);
    public static readonly Color Accent = Color.FromArgb(0xC7, 0x7D, 0xFF);
    public static readonly Color Muted = Color.FromArgb(0x6B, 0x5E, 0x7A);
    public static readonly Color Text = Color.FromArgb(0xEC, 0xE4, 0xF5);

    private static bool _enabled;

    public static void Enable()
    {
        if (_enabled)
            return;

        _enabled = true;

        try
        {
            System.Console.OutputEncoding = System.Text.Encoding.UTF8;
        }
        catch
        {
        }

        ConsoleExtensions.Enable();
    }

    public static Color Lerp(Color from, Color to, double t)
    {
        t = Math.Clamp(t, 0d, 1d);
        return Color.FromArgb(
            (int)(from.R + (to.R - from.R) * t),
            (int)(from.G + (to.G - from.G) * t),
            (int)(from.B + (to.B - from.B) * t));
    }

    public static string Gradient(string text) => Gradient(text, GradientFrom, GradientTo);

    public static string Gradient(string text, Color from, Color to)
    {
        if (string.IsNullOrEmpty(text))
            return text;

        System.Text.StringBuilder builder = new(text.Length * 12);
        int steps = Math.Max(text.Length - 1, 1);

        for (int i = 0; i < text.Length; i++)
        {
            char symbol = text[i];
            if (symbol == ' ')
            {
                builder.Append(symbol);
                continue;
            }

            builder.Append(symbol.ToString().Pastel(Lerp(from, to, (double)i / steps)));
        }

        return builder.ToString();
    }

    public static int Width
    {
        get
        {
            try
            {
                return System.Console.WindowWidth > 20 ? System.Console.WindowWidth : 100;
            }
            catch
            {
                return 100;
            }
        }
    }

    public static string Center(string plain, string rendered)
    {
        int pad = Math.Max((Width - plain.Length) / 2, 0);
        return new string(' ', pad) + rendered;
    }

    public static string Center(string rendered) => Center(Strip(rendered), rendered);

    public static string Strip(string text) => AnsiPattern.Replace(text, string.Empty);

    private static readonly Regex AnsiPattern = new((char)27 + @"\[[0-9;]*m", RegexOptions.Compiled);
}