using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace TBF.Rig.Network.Camera.RoiForFixedStartCJMS11.common
{
    public class Frame
    {
        public int Width { get; set; }
        public int Height { get; set; }

        public Frame() // standard frame
        {
            this.Width = 640;
            this.Height = 480;
        }

        public Frame(int width, int height)
        {
            Width = width;
            Height = height;
        }

        public static Frame StandardFrame()
        {
            return new Frame();
        }

        public override string ToString() => $"{Width}x{Height}";
        
        
        // Static method to parse string like "1920x1080"
        public static Frame Parse(string resolution)
        {
            var match = Regex.Match(resolution, @"^\s*(\d+)\s*[xX]\s*(\d+)\s*$");
            if (!match.Success)
            {
                throw new FormatException($"Invalid resolution format: '{resolution}'");
            }

            int width = int.Parse(match.Groups[1].Value);
            int height = int.Parse(match.Groups[2].Value);

            return new Frame(width, height);
        }
        
        ///
        /// Finds nearest frame based on selected dimension
        /// <b> example: </b>
        /// <code>
        /// var input = new Frame(1500, 800);
        /// //Nearest by Width
        /// var nearestByWidth = input.FindNearest(allFrames, f => f.Width);
        /// Console.WriteLine($"Nearest by width: {nearestByWidth}"); // → 1280x720
        /// //Nearest by Height
        /// var nearestByHeight = input.FindNearest(allFrames, f => f.Height);
        /// Console.WriteLine($"Nearest by height: {nearestByHeight}"); // → 1280x720
        /// </code>
        
        public Frame FindNearest(IEnumerable<Frame> candidates, Func<Frame, int> dimensionSelector)
        {
            int target = dimensionSelector(this);
            return candidates
                .OrderBy(f => Math.Abs(dimensionSelector(f) - target))
                .ThenBy(dimensionSelector) // tie-breaker: prefer smaller
                .FirstOrDefault();
        }
    }
}