namespace qtc_api.Data
{
    public class DataContext : DbContext
    {
        public DataContext(DbContextOptions<DataContext> options) : base(options)
        {
        }

        public DbSet<User> Users { get; set; }
        public DbSet<Room> Rooms { get; set; }
        public DbSet<RefreshToken> ValidRefreshTokens { get; set; }
        public DbSet<Contact> Contacts { get; set; }
        public DbSet<OwnedStoreItem> OwnedStoreItems { get; set; }

        protected override void OnConfiguring(DbContextOptionsBuilder options)
        {
            var dbProvider = Environment.GetEnvironmentVariable("DB_PROVIDER");
            var connectionString = Environment.GetEnvironmentVariable("DB_CONNECTION_STRING");

            if (dbProvider != null && connectionString != null)
            {
                switch (dbProvider)
                {
                    case "MySQL":
                        options.UseMySQL(connectionString);
                        break;
                    case "SQLite":
                        options.UseSqlite(connectionString);
                        break;
                    default: throw new Exception("Unsupported Database Provider. Please Check 'DB_PROVIDER' Environment Variable.");
                }
            }
            else throw new Exception("Cannot Find Environment Variables 'DB_PROVIDER' And 'DB_CONNECTION_STRING'. Please Check Environment.");
        }

        protected override void OnModelCreating(ModelBuilder builder)
        {
            // Users

            builder.Entity<User>().HasMany(e => e.ContactsList);
            builder.Entity<User>().HasMany(e => e.ContactsMade);
            builder.Entity<User>().HasMany(e => e.OwnedStoreItems);

            builder.Entity<User>()
                .Property<string>("_tagString")
                .HasColumnName("Tags");

            // Rooms (no relations)

            builder.Entity<Room>();

            // Refresh Tokens

            builder.Entity<RefreshToken>().HasOne(e => e.User)
                .WithMany(e => e.RefreshTokens)
                .HasForeignKey(e => e.UserID);

            // Contacts

            builder.Entity<Contact>().HasOne(e => e.Owner)
                .WithMany(e => e.ContactsMade)
                .HasForeignKey(e => e.OwnerId);

            builder.Entity<Contact>().HasOne(e => e.User)
                .WithMany(e => e.ContactsList)
                .HasForeignKey(e => e.UserId);

            // Purchased Store Items

            builder.Entity<OwnedStoreItem>().HasOne(e => e.User)
                .WithMany(e => e.OwnedStoreItems)
                .HasForeignKey(e => e.UserId);
        }
    }
}