using System;
using System.IO;
using System.Threading;
using System.Threading.Tasks;
using Humanizer;

namespace Artemis.Core
{
    /// <summary>
    ///     Represents a plugin prerequisite action that copies a folder
    /// </summary>
    public class CopyFolderAction : PluginPrerequisiteAction
    {
        /// <summary>
        ///     Creates a new instance of a copy folder action
        /// </summary>
        /// <param name="name">The name of the action</param>
        /// <param name="source">The source folder to copy</param>
        /// <param name="target">The target folder to copy to (will be created if needed)</param>
        public CopyFolderAction(string name, string source, string target) : base(name)
        {
            Source = source;
            Target = target;
        }

        /// <summary>
        ///     Gets the source directory
        /// </summary>
        public string Source { get; }

        /// <summary>
        ///     Gets or sets the target directory
        /// </summary>
        public string Target { get; }

        /// <inheritdoc />
        public override async Task Execute(CancellationToken cancellationToken)
        {
            DirectoryInfo source = new(Source);
            DirectoryInfo target = new(Target);

            if (!source.Exists)
                throw new ArtemisCoreException($"The source directory at '{source}' was not found.");

            int filesCopied = 0;
            FileInfo[] files = source.GetFiles("*", SearchOption.AllDirectories);

            foreach (FileInfo fileInfo in files)
            {
                string outputPath = fileInfo.FullName.Replace(source.FullName, target.FullName);
                string outputDir = Path.GetDirectoryName(outputPath)!;
                Utilities.CreateAccessibleDirectory(outputDir);

                void SubProgressOnProgressReported(object? sender, EventArgs e)
                {
                    if (SubProgress.ProgressPerSecond != 0)
                        Status = $"Copying {fileInfo.Name} - {SubProgress.ProgressPerSecond.Bytes().Humanize("#.##")}/sec";
                    else
                        Status = $"Copying {fileInfo.Name}";
                }

                Progress.Report((filesCopied, files.Length));
                SubProgress.ProgressReported += SubProgressOnProgressReported;

                await using FileStream sourceStream = fileInfo.OpenRead();
                await using FileStream destinationStream = File.Create(outputPath);

                await sourceStream.CopyToAsync(fileInfo.Length, destinationStream, SubProgress, cancellationToken);

                filesCopied++;
                SubProgress.ProgressReported -= SubProgressOnProgressReported;
            }

            Progress.Report((filesCopied, files.Length));
            Status = $"Finished copying {filesCopied} file(s)";
        }
    }
}