using System;
using System.Collections.Generic;
using System.IO;

namespace Chronos.Extensions
{
    /// <summary>
    /// Extension methods for the FileInfo and FileInfo-Array classes
    /// </summary>
    public static class FileInfoExtensions
    {
        #region · Extensions ·

        /// <summary>
        /// Renames a file.
        /// </summary>
        /// <param name="file">The file.</param>
        /// <param name="newName">The new name.</param>
        /// <returns>The renamed file</returns>
        /// <example>
        /// <code>
        /// var file = new FileInfo(@"c:\test.txt");
        /// file.Rename("test2.txt");
        /// </code></example>
        public static FileInfo Rename(this FileInfo file, string newName)
        {
            var filePath = Path.Combine(Path.GetDirectoryName(file.FullName), newName);

            file.MoveTo(filePath);

            return file;
        }

        /// <summary>
        /// Renames a without changing its extension.
        /// </summary>
        /// <param name="file">The file.</param>
        /// <param name="newName">The new name.</param>
        /// <returns>The renamed file</returns>
        /// <example>
        /// <code>
        /// var file = new FileInfo(@"c:\test.txt");
        /// file.RenameFileWithoutExtension("test3");
        /// </code></example>
        public static FileInfo RenameFileWithoutExtension(this FileInfo file, string newName)
        {
            var fileName = string.Concat(newName, file.Extension);

            file.Rename(fileName);

            return file;
        }

        /// <summary>
        /// Changes the files extension.
        /// </summary>
        /// <param name="file">The file.</param>
        /// <param name="newExtension">The new extension.</param>
        /// <returns>The renamed file</returns>
        /// <example>
        /// <code>
        /// var file = new FileInfo(@"c:\test.txt");
        /// file.ChangeExtension("xml");
        /// </code></example>
        public static FileInfo ChangeExtension(this FileInfo file, string newExtension)
        {
            newExtension = newExtension.EnsureStartsWith(".");

            var fileName = string.Concat(Path.GetFileNameWithoutExtension(file.FullName), newExtension);
            
            file.Rename(fileName);
            
            return file;
        }

        /// <summary>
        /// Changes the extensions of several files at once.
        /// </summary>
        /// <param name="files">The files.</param>
        /// <param name="newExtension">The new extension.</param>
        /// <returns>The renamed files</returns>
        /// <example>
        /// <code>
        /// var files = directory.GetFiles("*.txt", "*.xml");
        /// files.ChangeExtensions("tmp");
        /// </code></example>
        public static FileInfo[] ChangeExtensions(this FileInfo[] files, string newExtension)
        {
            files.ForEach(f => f.ChangeExtension(newExtension));

            return files;
        }

        /// <summary>
        /// Deletes several files at once and consolidates any exceptions.
        /// </summary>
        /// <param name="files">The files.</param>
        /// <example>
        /// <code>
        /// var files = directory.GetFiles("*.txt", "*.xml");
        /// files.Delete()
        /// </code></example>
        public static void Delete(this FileInfo[] files)
        {
            files.Delete(true);
        }

        /// <summary>
        /// Deletes several files at once and optionally consolidates any exceptions.
        /// </summary>
        /// <param name="files">The files.</param>
        /// <param name="consolidateExceptions">if set to <c>true</c> exceptions are consolidated and the processing is not interrupted.</param>
        /// <example>
        /// <code>
        /// var files = directory.GetFiles("*.txt", "*.xml");
        /// files.Delete()
        /// </code></example>
        public static void Delete(this FileInfo[] files, bool consolidateExceptions)
        {
            List<Exception> exceptions = null;

            foreach (var file in files)
            {
                try
                {
                    file.Delete();
                }
                catch (Exception e)
                {
                    if (consolidateExceptions)
                    {
                        if (exceptions == null)
                        {
                            exceptions = new List<Exception>();
                        }

                        exceptions.Add(e);
                    }
                    else
                    {
                        throw;
                    }
                }
            }

            if ((exceptions != null) && (exceptions.Count > 0))
            {
                throw new CombinedException
                (
                    "Error while deleting one or several files, see InnerExceptions array for details.",
                    exceptions.ToArray()
                );
            }
        }

        /// <summary>
        /// Copies several files to a new folder at once and consolidates any exceptions.
        /// </summary>
        /// <param name="files">The files.</param>
        /// <param name="targetPath">The target path.</param>
        /// <returns>The newly created file copies</returns>
        /// <example>
        /// <code>
        /// var files = directory.GetFiles("*.txt", "*.xml");
        /// var copiedFiles = files.CopyTo(@"c:\temp\");
        /// </code></example>
        public static FileInfo[] CopyTo(this FileInfo[] files, string targetPath)
        {
            return files.CopyTo(targetPath, true);
        }

        /// <summary>
        /// Copies several files to a new folder at once and optionally consolidates any exceptions.
        /// </summary>
        /// <param name="files">The files.</param>
        /// <param name="targetPath">The target path.</param>
        /// <param name="consolidateExceptions">if set to <c>true</c> exceptions are consolidated and the processing is not interrupted.</param>
        /// <returns>The newly created file copies</returns>
        /// <example>
        /// <code>
        /// var files = directory.GetFiles("*.txt", "*.xml");
        /// var copiedFiles = files.CopyTo(@"c:\temp\");
        /// </code></example>
        public static FileInfo[] CopyTo(this FileInfo[] files, string targetPath, bool consolidateExceptions)
        {
            var copiedfiles = new List<FileInfo>();
            List<Exception> exceptions = null;

            foreach (var file in files)
            {
                try
                {
                    var fileName = Path.Combine(targetPath, file.Name);

                    copiedfiles.Add(file.CopyTo(fileName));
                }
                catch (Exception e)
                {
                    if (consolidateExceptions)
                    {
                        if (exceptions == null)
                        {
                            exceptions = new List<Exception>();
                        }

                        exceptions.Add(e);
                    }
                    else
                    {
                        throw;
                    }
                }
            }

            if ((exceptions != null) && (exceptions.Count > 0))
            {
                throw new CombinedException
                (
                    "Error while copying one or several files, see InnerExceptions array for details.",
                    exceptions.ToArray()
                );
            }

            return copiedfiles.ToArray();
        }

        /// <summary>
        /// Moves several files to a new folder at once and optionally consolidates any exceptions.
        /// </summary>
        /// <param name="files">The files.</param>
        /// <param name="targetPath">The target path.</param>
        /// <returns>The moved files</returns>
        /// <example>
        /// <code>
        /// var files = directory.GetFiles("*.txt", "*.xml");
        /// files.MoveTo(@"c:\temp\");
        /// </code></example>
        public static FileInfo[] MoveTo(this FileInfo[] files, string targetPath)
        {
            return files.MoveTo(targetPath, true);
        }

        /// <summary>
        /// Movies several files to a new folder at once and optionally consolidates any exceptions.
        /// </summary>
        /// <param name="files">The files.</param>
        /// <param name="targetPath">The target path.</param>
        /// <param name="consolidateExceptions">if set to <c>true</c> exceptions are consolidated and the processing is not interrupted.</param>
        /// <returns>The moved files</returns>
        /// <example>
        /// <code>
        /// var files = directory.GetFiles("*.txt", "*.xml");
        /// files.MoveTo(@"c:\temp\");
        /// </code></example>
        public static FileInfo[] MoveTo(this FileInfo[] files, string targetPath, bool consolidateExceptions)
        {
            List<Exception> exceptions = null;

            foreach (var file in files)
            {
                try
                {
                    var fileName = Path.Combine(targetPath, file.Name);

                    file.MoveTo(fileName);
                }
                catch (Exception e)
                {
                    if (consolidateExceptions)
                    {
                        if (exceptions == null)
                        {
                            exceptions = new List<Exception>();
                        }

                        exceptions.Add(e);
                    }
                    else
                    {
                        throw;
                    }
                }
            }

            if ((exceptions != null) && (exceptions.Count > 0))
            {
                throw new CombinedException
                (
                    "Error while moving one or several files, see InnerExceptions array for details.",
                    exceptions.ToArray()
                );
            }

            return files;
        }

        /// <summary>
        /// Sets file attributes for several files at once
        /// </summary>
        /// <param name="files">The files.</param>
        /// <param name="attributes">The attributes to be set.</param>
        /// <returns>The changed files</returns>
        /// <example>
        /// <code>
        /// var files = directory.GetFiles("*.txt", "*.xml");
        /// files.SetAttributes(FileAttributes.Archive);
        /// </code></example>
        public static FileInfo[] SetAttributes(this FileInfo[] files, FileAttributes attributes)
        {
            foreach (var file in files)
            {
                file.Attributes = attributes;
            }

            return files;
        }

        /// <summary>
        /// Appends file attributes for several files at once (additive to any existing attributes)
        /// </summary>
        /// <param name="files">The files.</param>
        /// <param name="attributes">The attributes to be set.</param>
        /// <returns>The changed files</returns>
        /// <example>
        /// <code>
        /// var files = directory.GetFiles("*.txt", "*.xml");
        /// files.SetAttributesAdditive(FileAttributes.Archive);
        /// </code></example>
        public static FileInfo[] SetAttributesAdditive(this FileInfo[] files, FileAttributes attributes)
        {
            foreach (var file in files)
            {
                file.Attributes = (file.Attributes | attributes);
            }

            return files;
        }

        #endregion
    }
}