using BTCPayServer.Data;
using BTCPayServer.Models;
using NBitcoin;
using NBitcoin.DataEncoders;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;

namespace BTCPayServer.Services.Stores
{
    public class StoreRepository
    {
        private ApplicationDbContextFactory _ContextFactory;
        public StoreRepository(ApplicationDbContextFactory contextFactory)
        {
            _ContextFactory = contextFactory ?? throw new ArgumentNullException(nameof(contextFactory));
        }

        public async Task<StoreData> FindStore(string storeId)
        {
            using (var ctx = _ContextFactory.CreateContext())
            {
                return await ctx.FindAsync<StoreData>(storeId).ConfigureAwait(false);
            }
        }

        public async Task<StoreData> FindStore(string storeId, string userId)
        {
            if (userId == null)
                throw new ArgumentNullException(nameof(userId));
            using (var ctx = _ContextFactory.CreateContext())
            {
                return (await ctx
                    .UserStore
                    .Where(us => us.ApplicationUserId == userId && us.StoreDataId == storeId)
                    .Select(us => new
                    {
                        Store = us.StoreData,
                        Role = us.Role
                    }).ToArrayAsync())
                    .Select(us =>
                    {
                        us.Store.Role = us.Role;
                        return us.Store;
                    }).FirstOrDefault();
            }
        }

        public async Task<StoreData[]> GetStoresByUserId(string userId)
        {
            using (var ctx = _ContextFactory.CreateContext())
            {
                return await ctx.UserStore
                    .Where(u => u.ApplicationUserId == userId)
                    .Select(u => u.StoreData)
                    .ToArrayAsync();
            }
        }

        public async Task<StoreData> CreateStore(string ownerId, string name)
        {
            if (string.IsNullOrEmpty(name))
                throw new ArgumentException("name should not be empty", nameof(name));
            using (var ctx = _ContextFactory.CreateContext())
            {
                StoreData store = new StoreData
                {
                    Id = Encoders.Base58.EncodeData(RandomUtils.GetBytes(32)),
                    StoreName = name,
                    SpeedPolicy = Invoices.SpeedPolicy.MediumSpeed
                };
                var userStore = new UserStore
                {
                    StoreDataId = store.Id,
                    ApplicationUserId = ownerId,
                    Role = "Owner"
                };
                ctx.Add(store);
                ctx.Add(userStore);
                await ctx.SaveChangesAsync().ConfigureAwait(false);
                return store;
            }
        }

        public async Task RemoveStore(string storeId, string userId)
        {
            using (var ctx = _ContextFactory.CreateContext())
            {
                var storeUser = await ctx.UserStore.FirstOrDefaultAsync(o => o.StoreDataId == storeId && o.ApplicationUserId == userId);
                if (storeUser == null)
                    return;
                ctx.UserStore.Remove(storeUser);
                await ctx.SaveChangesAsync();
            }
        }

        public async Task UpdateStore(StoreData store)
        {
            using (var ctx = _ContextFactory.CreateContext())
            {
                var existing = await ctx.FindAsync<StoreData>(store.Id);
                ctx.Entry(existing).CurrentValues.SetValues(store);
                await ctx.SaveChangesAsync().ConfigureAwait(false);
            }
        }
    }
}