using FoodsharingSiegen.Contracts;
using FoodsharingSiegen.Contracts.Entity;
using Microsoft.EntityFrameworkCore;

namespace FoodsharingSiegen.Server.Data.Service
{
    /// <summary>
    /// The prospect service class (a. beging, 01.04.2022)
    /// </summary>
    /// <seealso cref="ServiceBase"/>
    public class ProspectService : ServiceBase
    {
        #region Setup/Teardown

        /// <summary>
        /// Initializes a new instance of the <see cref="ProspectService"/> class
        /// </summary>
        /// <param name="context">The context</param>
        public ProspectService(FsContext context) : base(context) { }

        #endregion

        #region Public Method AddInteraction

        /// <summary>
        /// Adds the interaction using the specified interaction (a. beging, 02.04.2022)
        /// </summary>
        /// <param name="interaction">The interaction</param>
        /// <returns>A task containing an operation result of interaction</returns>
        public async Task<OperationResult<Interaction>> AddInteraction(Interaction interaction)
        {
            try
            {
                var targetProspect = await Context.Prospects.Include(x => x.Interactions).FirstOrDefaultAsync(x => x.Id == interaction.ProspectId);
                if (targetProspect == null) return new OperationResult<Interaction>(new Exception("Invalid prospect id"));
                
                interaction.ProspectId = Guid.Empty;
                interaction.Created = DateTime.UtcNow;

                targetProspect.Interactions.Add(interaction);
                
                await Context.SaveChangesAsync();
                
                // Detatch entities
                Context.Entry(targetProspect).State = EntityState.Detached;
                Context.Entry(interaction).State = EntityState.Detached;
                
                return new OperationResult<Interaction>(interaction);
            }
            catch (Exception e)
            {
                return new OperationResult<Interaction>(e);
            }
        }

        #endregion

        public async Task<OperationResult> RemoveInteraction(Guid interactionId)
        {
            try
            {
                Context.Interactions.Remove(new Interaction { Id = interactionId });
                await Context.SaveChangesAsync();

                return new OperationResult();
            }
            catch (Exception e)
            {
                return new OperationResult(e);
            }
        }
        
        #region Public Method AddProspectAsync

        /// <summary>
        /// Adds the prospect using the specified prospect (a. beging, 01.04.2022)
        /// </summary>
        /// <param name="prospect">The prospect</param>
        /// <returns>A task containing an operation result of prospect</returns>
        public async Task<OperationResult<Prospect>> AddProspectAsync(Prospect? prospect)
        {
            try
            {
                if (prospect == null) return new OperationResult<Prospect>(new Exception("Cannot be empty"));

                prospect.Created = DateTime.UtcNow;
                prospect.Id = Guid.Empty;

                await Context.Prospects.AddAsync(prospect);
                var saveR = await Context.SaveChangesAsync();

                if (saveR > 0)
                    return new OperationResult<Prospect>(prospect);
            
                return new OperationResult<Prospect>(new Exception("Couldn't add prospect"));
            }
            catch (Exception e)
            {
                return new OperationResult<Prospect>(e);
            }
        }

        #endregion

        #region Public Method GetProspectsAsync

        /// <summary>
        /// Gets the users (a. beging, 01.04.2022)
        /// </summary>
        /// <returns>A task containing an operation result of list prospect</returns>
        public async Task<OperationResult<List<Prospect>>> GetProspectsAsync()
        {
            try
            {
                var prospects = await Context.Prospects.AsNoTracking().Include(x => x.Interactions.OrderBy(i => i.Date)).ThenInclude(x => x.User).OrderBy(x => x.Name).ToListAsync();
                return new OperationResult<List<Prospect>>(prospects);
            }
            catch (Exception e)
            {
                return new OperationResult<List<Prospect>>(e);
            }
        }

        #endregion
    }
}