using System;
using System.Collections.Generic;
using System.ComponentModel.Composition;
using System.IO;
using System.Linq;
using System.Text;
using Pithos.Interfaces;
using Pithos.Network;

namespace Pithos.Core.Agents
{
    [Export(typeof(Selectives))]
    public class Selectives
    {

        public Dictionary<Uri, List<Uri>> SelectiveUris { get; private set; }

        private Dictionary<Uri, List<string>> SelectivePaths { get; set; }

        public Selectives()
        {
            SelectiveUris = new Dictionary<Uri, List<Uri>>();
            SelectivePaths = new Dictionary<Uri, List<string>>();
        }

        public void SetSelectedUris(AccountInfo account,List<Uri> uris)
        {
            SelectiveUris[account.AccountKey] = uris;
            SelectivePaths[account.AccountKey] = UrisToFilePaths(account,uris);
        }

        public bool IsSelected(ObjectInfo info)
        {
            List<Uri> filterUris;
            return !SelectiveUris.TryGetValue(info.AccountKey, out filterUris) 
                || filterUris.Count ==0
                || filterUris.Any(f => info.Uri.IsAtOrDirectlyBelow(f));
        }

        public bool IsSelected(AccountInfo account,FileSystemInfo info)
        {
            return IsSelected(account,info.FullName);
        }

        public bool IsSelected(AccountInfo account, string fullPath)
        {
            List<string> paths;
            return !SelectivePaths.TryGetValue(account.AccountKey, out paths)
                || paths.Count == 0
                || paths.Any(fullPath.IsAtOrDirectlyBelow);
        }

        /// <summary>
        /// Return a list of absolute filepaths from a list of Uris
        /// </summary>
        /// <param name="uris"></param>
        /// <returns></returns>
        private List<string> UrisToFilePaths(AccountInfo account,IEnumerable<Uri> uris)
        {
            if (uris == null)
                return new List<string>();

            var accountPath = account.AccountPath;
            var storageUrl = account.StorageUri.ToString();
            var own = (from uri in uris
                       where uri.ToString().StartsWith(storageUrl)
                       let relativePath = account.StorageUri.MakeRelativeUri(uri).RelativeUriToFilePath()
                       //Trim the account name
                       select Path.Combine(accountPath, relativePath.After(account.UserName + '\\'))).ToList();
            var others = (from uri in uris
                          where !uri.ToString().StartsWith(storageUrl)
                          let relativePath = account.StorageUri.MakeRelativeUri(uri).RelativeUriToFilePath()
                          //Trim the account name
                          select Path.Combine(accountPath, "others-shared", relativePath)).ToList();
            return own.Union(others).ToList();
        }

    }
}