using Microsoft.EntityFrameworkCore;

namespace Kruzya.TelegramBot.RichSiteSummary.Data
{
    public class RichSiteSummaryContext : DbContext
    {
        /// <summary>
        /// Repository with all feeds in database.
        /// </summary>
        public DbSet<Feed> Feeds { get; set; }
        
        /// <summary>
        /// Repository with all posts in database.
        /// </summary>
        public DbSet<Post> Posts { get; set; }
        
        /// <summary>
        /// Repository with all subscriptions in database.
        /// </summary>
        public DbSet<Subscriber> Subscriptions { get; set; }

        /// <summary>
        /// Ensures the database is created and calls parent constructor.
        /// </summary>
        /// <param name="options"></param>
        public RichSiteSummaryContext(DbContextOptions<RichSiteSummaryContext> options) : base(options)
        {
            Database.EnsureCreated();
        }

        /// <summary>
        /// Setup the additional unique keys.
        /// </summary>
        /// <param name="modelBuilder"></param>
        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            // Setup unique keys for Feed entity.
            modelBuilder.Entity<Feed>().HasIndex(feed => feed.Url).IsUnique();
            modelBuilder.Entity<Feed>().HasIndex(feed => feed.HomePage).IsUnique();
            
            // Setup unique keys for Post entity.
            modelBuilder.Entity<Post>()
                .HasOne(p => p.Feed)
                .WithMany(f => f.Posts)
                .HasForeignKey(p => p.FeedId);

            modelBuilder.Entity<Post>().HasIndex(post => 
                new {post.FeedId, post.Url}).IsUnique();

            // Setup foreign keys for Subscriber entity.
            modelBuilder.Entity<Subscriber>()
                .HasOne(s => s.Feed)
                .WithMany(f => f.Subscribers)
                .HasForeignKey(s => s.FeedId);
        }
    }
}