using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace MarketAlly.AIPlugin.Analysis.Plugins
{
	public class CompilationManager
	{
		public CompilationManager()
		{
		}

		public async Task<CompilationResult> ValidateCompilationAsync(string solutionPath)
		{
			var result = new CompilationResult
			{
				StartTime = DateTime.UtcNow,
				SolutionPath = solutionPath
			};

			try
			{
				// Use dotnet build to validate compilation
				var processInfo = new ProcessStartInfo
				{
					FileName = "dotnet",
					Arguments = $"build \"{solutionPath}\" --verbosity quiet --nologo",
					RedirectStandardOutput = true,
					RedirectStandardError = true,
					UseShellExecute = false,
					CreateNoWindow = true
				};

				using var process = Process.Start(processInfo);
				if (process == null)
				{
					throw new InvalidOperationException("Failed to start dotnet build process");
				}
				
				var output = await process.StandardOutput.ReadToEndAsync();
				var error = await process.StandardError.ReadToEndAsync();
				await process.WaitForExitAsync();

				result.ExitCode = process.ExitCode;
				result.BuildOutput = output;
				result.BuildErrors = error;

				// Parse compilation results
				result.Status = process.ExitCode == 0 ? CompilationStatus.Success : CompilationStatus.Failed;

				// Use existing parsing logic from WarningsAnalysisPlugin
				result.Warnings = ParseWarningsFromBuildOutput(output + error);
				result.Errors = ParseErrorsFromBuildOutput(output + error);

				result.ErrorCount = result.Errors.Count;
				result.WarningCount = result.Warnings.Count;

				// Adjust status based on warnings
				if (result.Status == CompilationStatus.Success && result.WarningCount > 0)
				{
					result.Status = CompilationStatus.Warning;
				}
			}
			catch (Exception ex)
			{
				result.Status = CompilationStatus.Failed;
				result.ErrorMessage = ex.Message;
			}
			finally
			{
				result.EndTime = DateTime.UtcNow;
				result.Duration = result.EndTime - result.StartTime;
			}

			return result;
		}

		private List<CompilationDiagnostic> ParseWarningsFromBuildOutput(string buildOutput)
		{
			var warnings = new List<CompilationDiagnostic>();
			var lines = buildOutput.Split('\n', StringSplitOptions.RemoveEmptyEntries);

			foreach (var line in lines)
			{
				if (line.Contains("warning", StringComparison.OrdinalIgnoreCase))
				{
					var warning = TryParseDiagnosticLine(line.Trim(), "warning");
					if (warning != null)
					{
						warnings.Add(warning);
					}
				}
			}

			return warnings;
		}

		private List<CompilationDiagnostic> ParseErrorsFromBuildOutput(string buildOutput)
		{
			var errors = new List<CompilationDiagnostic>();
			var lines = buildOutput.Split('\n', StringSplitOptions.RemoveEmptyEntries);

			foreach (var line in lines)
			{
				if (line.Contains("error", StringComparison.OrdinalIgnoreCase) &&
					!line.Contains("warning", StringComparison.OrdinalIgnoreCase))
				{
					var error = TryParseDiagnosticLine(line.Trim(), "error");
					if (error != null)
					{
						errors.Add(error);
					}
				}
			}

			return errors;
		}

		private CompilationDiagnostic? TryParseDiagnosticLine(string line, string type)
		{
			var patterns = new[]
			{
				@"(.+?)\((\d+),(\d+)\):\s*warning\s+([A-Z]+\d+):\s*(.+)",
				@"warning\s+([A-Z]+\d+):\s*(.+)\s*\[(.+?)\]"
			};

			foreach (var pattern in patterns)
			{
				var match = System.Text.RegularExpressions.Regex.Match(line, pattern, System.Text.RegularExpressions.RegexOptions.IgnoreCase);
				if (match.Success)
				{
					if (match.Groups.Count >= 5 && !string.IsNullOrEmpty(match.Groups[1].Value))
					{
						return new CompilationDiagnostic
						{
							File = Path.GetFileName(match.Groups[1].Value),
							Line = int.TryParse(match.Groups[2].Value, out var parsedLine) ? parsedLine : 0,
							Column = int.TryParse(match.Groups[3].Value, out var parsedCol) ? parsedCol : 0,
							Code = match.Groups[4].Value,
							Message = match.Groups[5].Value.Trim(),
							Type = "warning"
						};
					}
					else if (match.Groups.Count >= 3)
					{
						return new CompilationDiagnostic
						{
							Code = match.Groups[1].Value,
							Message = match.Groups[2].Value.Trim(),
							File = match.Groups.Count > 3 ? Path.GetFileName(match.Groups[3].Value) : "Unknown",
							Type = "warning"
						};
					}
				}
			}

			return null;
		}
	}

	public class CompilationResult
	{
		public DateTime StartTime { get; set; }
		public DateTime EndTime { get; set; }
		public TimeSpan Duration { get; set; }
		public string SolutionPath { get; set; } = string.Empty;
		public CompilationStatus Status { get; set; }
		public int ExitCode { get; set; }
		public int ErrorCount { get; set; }
		public int WarningCount { get; set; }
		public int? PreviousErrorCount { get; set; }
		public string BuildOutput { get; set; } = string.Empty;
		public string BuildErrors { get; set; } = string.Empty;
		public string ErrorMessage { get; set; } = string.Empty;
		public List<CompilationDiagnostic> Errors { get; set; } = new();
		public List<CompilationDiagnostic> Warnings { get; set; } = new();
	}

	public enum CompilationStatus
	{
		Success,
		Warning,
		Failed
	}
}