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

namespace AxCopilot.Services.Agent;

public static class TaskDecomposer
{
	private static readonly Regex StepPattern = new Regex("(?:^|\\n)\\s*(?:(?:Step\\s*)?(\\d+)[.):\\-]\\s*)(.+?)(?=\\n|$)", RegexOptions.IgnoreCase | RegexOptions.Compiled);

	public static List<string> ExtractSteps(string text)
	{
		if (string.IsNullOrWhiteSpace(text))
		{
			return new List<string>();
		}
		MatchCollection matchCollection = StepPattern.Matches(text);
		if (matchCollection.Count < 2)
		{
			return new List<string>();
		}
		List<string> list = new List<string>();
		int num = 0;
		foreach (Match item in matchCollection)
		{
			if (int.TryParse(item.Groups[1].Value, out var result) && (result == num + 1 || num == 0))
			{
				string input = item.Groups[2].Value.Trim();
				input = Regex.Replace(input, "\\*\\*(.+?)\\*\\*", "$1");
				input = Regex.Replace(input, "\\*(.+?)\\*", "$1");
				input = Regex.Replace(input, "`(.+?)`", "$1");
				input = Regex.Replace(input, "\\[(.+?)\\]\\(.+?\\)", "$1");
				input = input.TrimEnd(':', ' ');
				if (input.Length >= 3 && input.Length <= 300)
				{
					list.Add(input);
					num = result;
				}
			}
		}
		return (list.Count >= 2) ? list.Take(20).ToList() : new List<string>();
	}

	public static int EstimateCurrentStep(List<string> steps, string toolName, string toolSummary, int lastStep)
	{
		if (steps.Count == 0)
		{
			return 0;
		}
		for (int i = lastStep; i < steps.Count; i++)
		{
			string text = steps[i].ToLowerInvariant();
			string value = toolName.ToLowerInvariant();
			string summary = toolSummary.ToLowerInvariant();
			if (text.Contains(value) || ContainsKeywordOverlap(text, summary))
			{
				return i;
			}
		}
		return Math.Min(lastStep + 1, steps.Count - 1);
	}

	private static bool ContainsKeywordOverlap(string stepText, string summary)
	{
		if (string.IsNullOrEmpty(summary))
		{
			return false;
		}
		IEnumerable<string> source = (from w in summary.Split(' ', '/', '\\', '.', ',', ':', ';', '(', ')')
			where w.Length >= 3
			select w).Take(5);
		return source.Any((string w) => stepText.Contains(w));
	}
}