using Seenginx.Models;
using Seenginx.Services;
using Seenginx.Services.Models;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Seenginx.Services
{
	public class SystemDService : ISystemDService
	{

		private readonly SeenginxSettings Settings;

		private readonly CommandService CommandService;

		public SystemDService(SeenginxSettings configPaths, CommandService commandService)
		{
			Settings = configPaths;
			CommandService = commandService;
		}

		public async Task<IEnumerable<ConfigFile>> GetFilesAsync()
		{
			await Task.Run(() => { });
			var rootConfigs = Directory.GetFiles(Settings.systemd.rootPath, "*.service");
			var rootDraftConfigs = Directory.GetFiles(Settings.systemd.rootPath, "*.service.draft");

			var rootConfigFiles = rootConfigs.Select(fp =>
			{
				var name = Path.GetFileNameWithoutExtension(fp);
				var configFile = new ConfigFile();
				configFile.CanBeDeleted = true;
				configFile.Folder = string.Empty;
				configFile.LastUpdated = File.GetLastWriteTime(fp);
				configFile.Name = name;
				configFile.FullPath = Path.Combine(Settings.systemd.rootPath, $"{configFile.Name}.service");
				configFile.Body = File.ReadAllText(fp);
				if (rootDraftConfigs.Any(cfp => cfp.Contains(name)))
					configFile.DraftBody = File.ReadAllText(rootDraftConfigs.First(cfp => cfp.Contains(name)));

				return configFile;
			});
			
			var finalList = new List<ConfigFile>();
			finalList.AddRange(rootConfigFiles);

			finalList = finalList.OrderBy(cf => cf.Name).ToList();

			return finalList;
		}

		public async Task<IEnumerable<Template>> GetTemplates()
		{
			var templates = new List<Template>();
			try
			{
				var systemdTemplateDirectory = Path.Combine(Directory.GetCurrentDirectory(), "wwwroot", "templates", "systemd");
				var systemdTemplateFiles = Directory.GetFiles(systemdTemplateDirectory, "*.template");

				foreach (var templateFilePath in systemdTemplateFiles)
				{
					var template = new Template();
					var templateFileLines = await File.ReadAllLinesAsync(templateFilePath);
					template.Name = templateFileLines.FirstOrDefault();
					template.Code = string.Join(Environment.NewLine, templateFileLines.Skip(2));
					templates.Add(template);
				}

				return templates;
			}
			catch (Exception ex)
			{
				throw ex;
			}
		}


		public async Task<Result> ValidateForAddFileAsync(NewFileForm newFileForm)
		{
			var validationResult = new Result();
			try
			{
				var filePath = Path.Combine(Settings.systemd.rootPath, $"{newFileForm.Name}.service");

				if (File.Exists(filePath))
					return validationResult.Invalidate($"There's already a file with the '{newFileForm.Name}.service' name.");

				return validationResult;
			}
			catch (Exception ex)
			{
				return validationResult.Invalidate($"Exception at {nameof(ValidateForAddFileAsync)}()", ex);
			}
		}

		public async Task<Result<ConfigFile>> AddFileAsync(NewFileForm newFileForm)
		{
			var addResult = new Result<ConfigFile>();
			try
			{
				var newFile = new ConfigFile();
				newFile.Name = newFileForm.Name;
				newFile.Folder = string.Empty;
				newFile.FullPath = Path.Combine(Settings.systemd.rootPath, newFile.Folder, $"{newFileForm.Name}.service");
				newFile.Body = newFileForm.SelectedTemplate == 0.ToString() ? string.Empty : (await GetTemplates()).SingleOrDefault(t => t.Name == newFileForm.SelectedTemplate)?.Code;
				newFile.LastUpdated = DateTime.UtcNow;

				await File.WriteAllTextAsync(newFile.FullPath, newFile.Body, Encoding.UTF8);

				addResult.SetData(newFile);

				return addResult;
			}
			catch (Exception ex)
			{
				return addResult.Invalidate(ex.Message, ex);
			}
		}


		public async Task<Result> ValidateForDeleteFileAsync(ConfigFile configFile)
		{
			var validationResult = new Result();
			try
			{
				if (File.Exists(configFile.FullPath))
					return validationResult.Invalidate($"File '{configFile.FullPath}' not found.");

				return validationResult;
			}
			catch (Exception ex)
			{
				return validationResult.Invalidate(ex.Message, ex);
			}
		}

		public async Task<Result> DeleteFileAsync(ConfigFile configFile)
		{
			var result = new Result();
			try
			{
				if (!File.Exists(configFile.FullPath))
					return result.Invalidate($"File '{configFile.FullPath}' not found.");

				File.Delete(configFile.FullPath);

				return result;
			}
			catch (Exception ex)
			{
				return result.Invalidate(ex.Message, ex);
			}
		}


		public async Task<Result> ValidateForSaveFileAsync(ConfigFile configFile)
		{
			var validationResult = new Result();
			try
			{
				if (File.Exists(configFile.FullPath))
					return validationResult.Invalidate($"File '{configFile.FullPath}' not found.");

				return validationResult;
			}
			catch (Exception ex)
			{
				return validationResult.Invalidate(ex.Message, ex);
			}
		}

		public async Task<Result<ConfigFile>> SaveFileAsync(ConfigFile configFile)
		{
			var saveResult = new Result<ConfigFile>();
			try
			{
				await File.WriteAllTextAsync(Path.Combine(Settings.systemd.rootPath, $"{configFile.Name}.service"), configFile.Body, Encoding.UTF8);

				return saveResult;
			}
			catch (Exception ex)
			{
				return saveResult.Invalidate(ex.Message, ex);
			}
		}


		public async Task<Result> ValidateForSaveDraftFileAsync(ConfigFile configFile)
		{
			var validationResult = new Result();
			try
			{
				var draftPathName = $"{configFile.FullPath}.draft";

				if (!File.Exists(draftPathName))
					return validationResult.Invalidate($"File '{draftPathName}' not found.");

				return validationResult;
			}
			catch (Exception ex)
			{
				return validationResult.Invalidate(ex.Message, ex);
			}
		}

		public async Task<Result<ConfigFile>> SaveDraftFileAsync(ConfigFile configFile)
		{
			var saveDraftResult = new Result<ConfigFile>();
			try
			{
				await File.WriteAllTextAsync(Path.Combine(Settings.systemd.rootPath, $"{configFile.Name}.service.draft"), configFile.DraftBody, Encoding.UTF8);

				return saveDraftResult;
			}
			catch (Exception ex)
			{
				return saveDraftResult.Invalidate(ex.Message, ex);
			}
		}


		public async Task<Result> ValidateForRenameFileAsync(List<ConfigFile> configFiles, ConfigFile selectedConfigFile, string newName)
		{
			var renameResult = new Result();
			try
			{


				if (configFiles.Count(cf => cf.Name == newName) > 0)
					return renameResult.Invalidate($"File '{selectedConfigFile.FullPath}' already exists.");




				if (!File.Exists(selectedConfigFile.FullPath))
					return renameResult.Invalidate($"Original file '{selectedConfigFile.FullPath}' not found.");

				var newPathName = Path.Combine(Settings.systemd.rootPath, $"{newName}.service");
				if (File.Exists(newPathName))
					return renameResult.Invalidate($"The file '{newPathName}' already exists.");

				return renameResult;
			}
			catch (Exception ex)
			{
				return renameResult.Invalidate(ex.Message, ex);
			}
		}

		public async Task<Result<ConfigFile>> RenameFileAsync(ConfigFile configFile, string newName)
		{
			var renameResult = new Result<ConfigFile>();
			try
			{
				var originalPathName = Path.Combine(Settings.systemd.rootPath, $"{configFile.Name}.service");
				var newPathName = Path.Combine(Settings.systemd.rootPath, newName);

				File.Move(originalPathName, newPathName, overwrite: false);
				if(configFile.DraftBody != null)
					File.Move(originalPathName, newPathName, overwrite: false);

				configFile.FullPath = newPathName;
				renameResult.SetData(configFile);

				return renameResult;
			}
			catch (Exception ex)
			{
				return renameResult.Invalidate(ex.Message, ex);
			}
		}


	}
}