using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using IdentityServer4.EntityFramework.DbContexts;
using IdentityServer4.EntityFramework.Mappers;
using IdentityServer4.Models;
using IdentityServer4.Stores;
using Microsoft.EntityFrameworkCore;

namespace xIds.Stores
{
    public class XPersistedGrantStore : IPersistedGrantStore
    {
        private readonly PersistedGrantDbContext dbContext;

        public XPersistedGrantStore(PersistedGrantDbContext dbContext)
        {
            this.dbContext = dbContext;
        }

        public async Task<IEnumerable<PersistedGrant>> GetAllAsync(string subjectId)
        {
            //
            var result = (await dbContext.PersistedGrants
                .Where(g => g.SubjectId == subjectId)
                .AsNoTracking()
                .Select(res => res.ToModel())
                .ToListAsync()).AsEnumerable();

            //
            return result;
        }

        public async Task<PersistedGrant> GetAsync(string key)
        {
            //
            var result = await dbContext.PersistedGrants
                .FirstOrDefaultAsync(g => g.Key == key);

            //
            return result.ToModel();
        }

        public async Task RemoveAllAsync(string subjectId, string clientId)
        {
            //
            var items = await dbContext.PersistedGrants
                .Where(g =>
                    g.SubjectId == subjectId &&
                    g.ClientId == clientId)
                .ToListAsync();

            //
            dbContext.PersistedGrants.RemoveRange(items);

            //
            await dbContext.SaveChangesAsync();
        }

        public async Task RemoveAllAsync(string subjectId, string clientId, string type)
        {
            //
            var items = await dbContext.PersistedGrants
                .Where(g =>
                    g.SubjectId == subjectId &&
                    g.ClientId == clientId &&
                    g.Type == type)
                .ToListAsync();

            //
            dbContext.PersistedGrants.RemoveRange(items);

            //
            await dbContext.SaveChangesAsync();
        }

        public async Task RemoveAsync(string key)
        {
            //
            var items = await dbContext.PersistedGrants
                .Where(g => g.Key == key)
                .ToListAsync();

            //
            dbContext.PersistedGrants.RemoveRange(items);

            //
            await dbContext.SaveChangesAsync();
        }

        public async Task<bool> IsExistsAsync(string key)
        {
            return await this.dbContext.PersistedGrants.AnyAsync(g => g.Key == key);
        }

        public async Task<bool> IsExistsAsync(PersistedGrant grant)
        {
            return await IsExistsAsync(grant.Key);
        }

        public async Task AddOrUpdateAsync(PersistedGrant grant)
        {
            //
            var isExists = await IsExistsAsync(grant);
            if (isExists)
            {
                await UpdateAsync(grant);
            }
            else
            {
                await AddAsync(grant);
            }
        }

        public async Task AddAsync(PersistedGrant grant)
        {
            //
            var item = grant.ToEntity();
            await dbContext.PersistedGrants.AddAsync(item);
            await dbContext.SaveChangesAsync();
        }

        public async Task UpdateAsync(PersistedGrant grant)
        {
            //
            var item = grant.ToEntity();
            var entity = dbContext.Attach(item);
            entity.State = EntityState.Modified;
            await dbContext.SaveChangesAsync();
        }

        public async Task StoreAsync(PersistedGrant grant)
        {
            await AddOrUpdateAsync(grant);
        }

        //
        // TODO: Complete this ...
        public Task<IEnumerable<PersistedGrant>> GetAllAsync(PersistedGrantFilter filter)
        {
            throw new System.NotImplementedException();
        }

        //
        // TODO: Complete this ...
        public Task RemoveAllAsync(PersistedGrantFilter filter)
        {
            throw new System.NotImplementedException();
        }
    }
}