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

namespace Contacts
{
    /// <summary>
    /// Manages the contacts database and facilitates viewing the database via searching and sorting. Contains methods to update the current view.
    /// </summary>
    public class FileIO
    {
        public IEnumerable<Contact> currentState { get; set; }
        private readonly List<Contact> _contacts = new();
        //private string _filepath = "~/.contacts";

        /// <summary>
        /// Create the FileIo object and set default view.
        /// </summary>
        public FileIO()
        {
            currentState =
                from c in _contacts
                select c;
        }

        /// <summary>
        ///     Facilitates incoming compatability with .vcf, .card, and .csv filetypes for contacts into this console-based
        ///     contacts manager.
        /// </summary>
        /// <param name="resolver"></param>
        public void Import(Resolver resolver)
        {
            resolver.Parse();
            List<Contact> contacts = resolver.Contacts;
            foreach (Contact c in contacts)
                _contacts.Add(c);
        }

        /// <summary>
        /// Facilitates outgoing compatability with .vcf, .card, and .csv filetypes for contacts into this console-based contacts manager.
        /// </summary>
        /// <param name="onIos"></param>
        public void Export(bool onIos)
        {
            // TODO
        }

        /// <summary>
        /// Save the contacts in the database to a file.
        /// </summary>
        /// <param name="targetFilePath">Path to the file on computer</param>
        public void Save()
        {
            using (StreamWriter writer = new StreamWriter("yourContacts.save"))
            {
                foreach (Contact c in _contacts)
                {
                    writer.WriteLine($"{c.SaveString()}");
                }
            }
        }

        /// <summary>
        /// Load the saved contacts in the database.
        /// </summary>
        public void Load()
        {
            using (StreamReader reader = new StreamReader("yourContacts.save"))
            {
                while (!reader.EndOfStream)
                {
                    _contacts.Add(new Contact(reader.ReadLine()));
                }
            }
        }
    }
}