using System;
using System.Collections.Generic;
using Umbraco.Core.Auditing;
using Umbraco.Core.Models;
using Umbraco.Core.Persistence;
using Umbraco.Core.Persistence.Repositories;
using Umbraco.Core.Persistence.UnitOfWork;

namespace Umbraco.Core.Services
{
    /// <summary>
    /// Represents the File Service, which is an easy access to operations involving <see cref="IFile"/> objects like Scripts, Stylesheets and Templates
    /// </summary>
    public class FileService : IFileService
    {
	    private readonly RepositoryFactory _repositoryFactory;
	    private readonly IUnitOfWork _fileUnitOfWork;
        private readonly IDatabaseUnitOfWork _dataUnitOfWork;
	    private readonly IStylesheetRepository _stylesheetRepository;
	    private readonly IScriptRepository _scriptRepository;
	    private readonly ITemplateRepository _templateRepository;

        public FileService(RepositoryFactory repositoryFactory)
			: this(new FileUnitOfWorkProvider(), new PetaPocoUnitOfWorkProvider(), repositoryFactory)
        {
        }

		public FileService(IUnitOfWorkProvider fileProvider, IDatabaseUnitOfWorkProvider dataProvider, RepositoryFactory repositoryFactory)
        {
			_repositoryFactory = repositoryFactory;
			_fileUnitOfWork = fileProvider.GetUnitOfWork();
            _dataUnitOfWork = dataProvider.GetUnitOfWork();
	        _templateRepository = _repositoryFactory.CreateTemplateRepository(_dataUnitOfWork);
	        _stylesheetRepository = _repositoryFactory.CreateStylesheetRepository(_fileUnitOfWork);
	        _scriptRepository = _repositoryFactory.CreateScriptRepository(_fileUnitOfWork);
        }

        /// <summary>
        /// Gets a list of all <see cref="Stylesheet"/> objects
        /// </summary>
        /// <returns>An enumerable list of <see cref="Stylesheet"/> objects</returns>
        public IEnumerable<Stylesheet> GetStylesheets(params string[] names)
        {
            var repository = _stylesheetRepository;
            return repository.GetAll(names);
        }

        /// <summary>
        /// Gets a <see cref="Stylesheet"/> object by its name
        /// </summary>
        /// <param name="name">Name of the stylesheet incl. extension</param>
        /// <returns>A <see cref="Stylesheet"/> object</returns>
        public Stylesheet GetStylesheetByName(string name)
        {
            var repository = _stylesheetRepository;
            return repository.Get(name);
        }

        /// <summary>
        /// Saves a <see cref="Stylesheet"/>
        /// </summary>
        /// <param name="stylesheet"><see cref="Stylesheet"/> to save</param>
        /// <param name="userId"></param>
        public void SaveStylesheet(Stylesheet stylesheet, int userId = -1)
        {
            var e = new SaveEventArgs();
            if (Saving != null)
                Saving(stylesheet, e);

            if (!e.Cancel)
            {
                _stylesheetRepository.AddOrUpdate(stylesheet);
                _fileUnitOfWork.Commit();

                if (Saved != null)
                    Saved(stylesheet, e);

                Audit.Add(AuditTypes.Save, string.Format("Save Stylesheet performed by user"), userId == -1 ? 0 : userId, -1);
            }
        }

        /// <summary>
        /// Deletes a stylesheet by its name
        /// </summary>
        /// <param name="name">Name incl. extension of the Stylesheet to delete</param>
        /// <param name="userId"></param>
        public void DeleteStylesheet(string name, int userId = -1)
        {
            var stylesheet = _stylesheetRepository.Get(name);

            var e = new DeleteEventArgs();
            if (Deleting != null)
                Deleting(stylesheet, e);

            if (!e.Cancel)
            {
                _stylesheetRepository.Delete(stylesheet);
                _fileUnitOfWork.Commit();

                if (Deleted != null)
                    Deleted(stylesheet, e);

                Audit.Add(AuditTypes.Delete, string.Format("Delete Stylesheet performed by user"), userId == -1 ? 0 : userId, -1);
            }
        }

        /// <summary>
        /// Validates a <see cref="Stylesheet"/>
        /// </summary>
        /// <param name="stylesheet"><see cref="Stylesheet"/> to validate</param>
        /// <returns>True if Stylesheet is valid, otherwise false</returns>
        public bool ValidateStylesheet(Stylesheet stylesheet)
        {
            return stylesheet.IsValid() && stylesheet.IsFileValidCss();
        }

        /// <summary>
        /// Gets a list of all <see cref="Script"/> objects
        /// </summary>
        /// <returns>An enumerable list of <see cref="Script"/> objects</returns>
        public IEnumerable<Script> GetScripts(params string[] names)
        {
            var repository = _scriptRepository;
            return repository.GetAll(names);
        }

        /// <summary>
        /// Gets a <see cref="Script"/> object by its name
        /// </summary>
        /// <param name="name">Name of the script incl. extension</param>
        /// <returns>A <see cref="Script"/> object</returns>
        public Script GetScriptByName(string name)
        {
            var repository = _scriptRepository;
            return repository.Get(name);
        }

        /// <summary>
        /// Saves a <see cref="Script"/>
        /// </summary>
        /// <param name="script"><see cref="Script"/> to save</param>
        /// <param name="userId"></param>
        public void SaveScript(Script script, int userId = -1)
        {
            var e = new SaveEventArgs();
            if (Saving != null)
                Saving(script, e);

            if (!e.Cancel)
            {
                _scriptRepository.AddOrUpdate(script);
                _fileUnitOfWork.Commit();

                if (Saved != null)
                    Saved(script, e);

                Audit.Add(AuditTypes.Save, string.Format("Save Script performed by user"), userId == -1 ? 0 : userId, -1);
            }
        }

        /// <summary>
        /// Deletes a script by its name
        /// </summary>
        /// <param name="name">Name incl. extension of the Script to delete</param>
        /// <param name="userId"></param>
        public void DeleteScript(string name, int userId = -1)
        {
            var script = _scriptRepository.Get(name);

            var e = new DeleteEventArgs();
            if (Deleting != null)
                Deleting(script, e);

            if (!e.Cancel)
            {
                _scriptRepository.Delete(script);
                _fileUnitOfWork.Commit();

                if (Deleted != null)
                    Deleted(script, e);

                Audit.Add(AuditTypes.Delete, string.Format("Delete Script performed by user"), userId == -1 ? 0 : userId, -1);
            }
        }

        /// <summary>
        /// Validates a <see cref="Script"/>
        /// </summary>
        /// <param name="script"><see cref="Script"/> to validate</param>
        /// <returns>True if Script is valid, otherwise false</returns>
        public bool ValidateScript(Script script)
        {
            return script.IsValid();
        }

        /// <summary>
        /// Gets a list of all <see cref="ITemplate"/> objects
        /// </summary>
        /// <returns>An enumerable list of <see cref="ITemplate"/> objects</returns>
        public IEnumerable<ITemplate> GetTemplates(params string[] aliases)
        {
            var repository = _templateRepository;
            return repository.GetAll(aliases);
        }

        /// <summary>
        /// Gets a <see cref="ITemplate"/> object by its alias
        /// </summary>
        /// <param name="alias">Alias of the template</param>
        /// <returns>A <see cref="Template"/> object</returns>
        public ITemplate GetTemplateByAlias(string alias)
        {
            var repository = _templateRepository;
            return repository.Get(alias);
        }

        /// <summary>
        /// Saves a <see cref="Template"/>
        /// </summary>
        /// <param name="template"><see cref="Template"/> to save</param>
        /// <param name="userId"></param>
        public void SaveTemplate(ITemplate template, int userId = -1)
        {
            var e = new SaveEventArgs();
            if (Saving != null)
                Saving(template, e);

            if (!e.Cancel)
            {
                _templateRepository.AddOrUpdate(template);
                _dataUnitOfWork.Commit();

                if (Saved != null)
                    Saved(template, e);

                Audit.Add(AuditTypes.Save, string.Format("Save Template performed by user"), userId == -1 ? 0 : userId, template.Id);
            }
        }

        /// <summary>
        /// Deletes a template by its alias
        /// </summary>
        /// <param name="alias">Alias of the <see cref="ITemplate"/> to delete</param>
        /// <param name="userId"></param>
        public void DeleteTemplate(string alias, int userId = -1)
        {
            var template = _templateRepository.Get(alias);

            var e = new DeleteEventArgs();
            if (Deleting != null)
                Deleting(template, e);

            if (!e.Cancel)
            {
                _templateRepository.Delete(template);
                _dataUnitOfWork.Commit();

                if (Deleted != null)
                    Deleted(template, e);

                Audit.Add(AuditTypes.Delete, string.Format("Delete Template performed by user"), userId == -1 ? 0 : userId, template.Id);
            }
        }

        /// <summary>
        /// Validates a <see cref="ITemplate"/>
        /// </summary>
        /// <param name="template"><see cref="ITemplate"/> to validate</param>
        /// <returns>True if Script is valid, otherwise false</returns>
        public bool ValidateTemplate(ITemplate template)
        {
            return template.IsValid();
        }

        //TODO Method to change name and/or alias of view/masterpage template

        #region Event Handlers
        /// <summary>
        /// Occurs before Delete
        /// </summary>
        public static event EventHandler<DeleteEventArgs> Deleting;

        /// <summary>
        /// Occurs after Delete
        /// </summary>
        public static event EventHandler<DeleteEventArgs> Deleted;

        /// <summary>
        /// Occurs before Save
        /// </summary>
        public static event EventHandler<SaveEventArgs> Saving;

        /// <summary>
        /// Occurs after Save
        /// </summary>
        public static event EventHandler<SaveEventArgs> Saved;
        #endregion
    }
}