using System.Drawing;
using Microsoft.Extensions.Logging;
using Pastel;

namespace Yuanshen.Common.Console;

public sealed class ThemedLoggerProvider : ILoggerProvider
{
    private readonly LogLevel _minimum;

    public ThemedLoggerProvider(LogLevel minimum = LogLevel.Information)
    {
        ConsoleTheme.Enable();
        _minimum = minimum;
    }

    public ILogger CreateLogger(string categoryName) => new ThemedLogger(categoryName, _minimum);

    public void Dispose()
    {
    }

    private sealed class ThemedLogger : ILogger
    {
        private static readonly Color Timestamp = Color.FromArgb(0x5A, 0x4E, 0x68);
        private static readonly Color Category = Color.FromArgb(0x9A, 0x7F, 0xC0);

        private readonly string _category;
        private readonly LogLevel _minimum;

        public ThemedLogger(string category, LogLevel minimum)
        {
            int lastDot = category.LastIndexOf('.');
            _category = lastDot >= 0 ? category[(lastDot + 1)..] : category;
            _minimum = minimum;
        }

        public IDisposable? BeginScope<TState>(TState state) where TState : notnull => null;

        public bool IsEnabled(LogLevel logLevel) => logLevel >= _minimum;

        public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception? exception,
            Func<TState, Exception?, string> formatter)
        {
            if (!IsEnabled(logLevel))
                return;

            string message = formatter(state, exception);
            if (string.IsNullOrEmpty(message) && exception is null)
                return;

            (Color color, string label) = logLevel switch
            {
                LogLevel.Trace => (Color.FromArgb(0x5A, 0x4E, 0x68), "trc"),
                LogLevel.Debug => (Color.FromArgb(0x8B, 0x7D, 0x9B), "dbg"),
                LogLevel.Information => (ConsoleTheme.Accent, "inf"),
                LogLevel.Warning => (Color.FromArgb(0xFF, 0xB3, 0x4D), "wrn"),
                LogLevel.Error => (Color.FromArgb(0xFF, 0x5C, 0x7A), "err"),
                LogLevel.Critical => (Color.FromArgb(0xFF, 0x2D, 0x95), "crt"),
                _ => (ConsoleTheme.Text, "log")
            };

            string line =
                $"{DateTime.Now:HH:mm:ss}".Pastel(Timestamp) + " " +
                label.Pastel(color) + " " +
                _category.Pastel(Category) + " " +
                message.Pastel(ConsoleTheme.Text);

            ConsolePrompt.Write(line);

            if (exception is not null)
                ConsolePrompt.Write(exception.ToString().Pastel(Color.FromArgb(0xFF, 0x5C, 0x7A)));
        }
    }
}