using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using System.Data.Entity.ModelConfiguration;
using System.Data.Entity.ModelConfiguration.Conventions;
using HeuristicLab.Services.Optimization.Billing.Interfaces;
using HeuristicLab.Services.Optimization.Billing.Model;

namespace HeuristicLab.Services.Optimization.Billing.DataAccess {
  public class BillingContext : DbContext {
    public DbSet<Product> Products { get; set; }
    public DbSet<User> Users { get; set; }
    public DbSet<Order> Orders { get; set; }
    public DbSet<OrderLine> OrderLines { get; set; }
    public DbSet<Invoice> Invoices { get; set; }
    public DbSet<InvoiceLine> InvoiceLines { get; set; }
    public DbSet<UsageRecord> UsageRecords { get; set; }
    public DbSet<ContactInformation> ContactInformations { get; set; }
    public DbSet<PaymentInformation> PaymentInformations { get; set; }

    public BillingContext()
      : this("name=BillingContext") {

    }

    public BillingContext(string connectionString)
      : base(connectionString) {

      Database.SetInitializer(new BillingContextInitiliazer());

      // Hook up event to mark existing entities as Unchanged
      ((IObjectContextAdapter)this).ObjectContext.ObjectMaterialized += (sender, args) => {
        var entity = args.Entity as IObjectWithState;
        if (entity != null) {
          entity.EntityState = State.Unchanged;
        }
      };

      this.Configuration.LazyLoadingEnabled = false;
      this.Configuration.ProxyCreationEnabled = false;
    }

    protected override void OnModelCreating(DbModelBuilder modelBuilder) {
      modelBuilder.Configurations.Add(new ContactInformationConfiguration());
      modelBuilder.Configurations.Add(new PaymentInformationConfiguration());
      modelBuilder.Configurations.Add(new ProductConfiguration());
      modelBuilder.Configurations.Add(new OrderConfiguration());
      modelBuilder.Configurations.Add(new OrderLineConfiguration());
      modelBuilder.Configurations.Add(new InvoiceConfiguration());
      modelBuilder.Configurations.Add(new InvoiceLineConfiguration());
      modelBuilder.Configurations.Add(new UsageRecordConfiguration());
      modelBuilder.Configurations.Add(new UserConfiguration());

      modelBuilder.Conventions.Remove<OneToManyCascadeDeleteConvention>();

      base.OnModelCreating(modelBuilder);
    }

    #region EntityTypeConfigurations

    private class ContactInformationConfiguration : EntityTypeConfiguration<ContactInformation> {
      internal ContactInformationConfiguration() {
        this.Ignore(ci => ci.EntityState);
      }
    }

    private class PaymentInformationConfiguration : EntityTypeConfiguration<PaymentInformation> {
      internal PaymentInformationConfiguration() {
        this.Ignore(pi => pi.EntityState);
      }
    }

    private class ProductConfiguration : EntityTypeConfiguration<Product> {
      internal ProductConfiguration() {
        this.Ignore(p => p.EntityState);
      }
    }

    private class OrderConfiguration : EntityTypeConfiguration<Order> {
      internal OrderConfiguration() {
        this.Ignore(o => o.EntityState);
        this.HasRequired(o => o.User).WithMany().HasForeignKey(o => o.UserId);
        // TODO: OrderState?
      }
    }

    private class OrderLineConfiguration : EntityTypeConfiguration<OrderLine> {
      internal OrderLineConfiguration() {
        this.Ignore(ol => ol.EntityState);
        this.HasRequired(ol => ol.Order).WithMany(o => o.OrderLines).HasForeignKey(ol => ol.OrderId).WillCascadeOnDelete(true);
        this.HasRequired(ol => ol.Product).WithMany().HasForeignKey(ol => ol.ProductId);
      }
    }

    private class InvoiceConfiguration : EntityTypeConfiguration<Invoice> {
      internal InvoiceConfiguration() {
        this.Ignore(i => i.EntityState);
        this.HasRequired(i => i.User).WithMany().HasForeignKey(i => i.UserId);
        this.HasRequired(i => i.Order).WithMany(o => o.Invoices).HasForeignKey(i => i.OrderId);
      }
    }

    private class InvoiceLineConfiguration : EntityTypeConfiguration<InvoiceLine> {
      internal InvoiceLineConfiguration() {
        this.Ignore(i => i.EntityState);
        this.HasRequired(il => il.Invoice).WithMany(i => i.InvoiceLines).HasForeignKey(il => il.InvoiceId).WillCascadeOnDelete(true);
        this.HasRequired(il => il.Product).WithMany().HasForeignKey(il => il.ProductId);
      }
    }

    private class UsageRecordConfiguration : EntityTypeConfiguration<UsageRecord> {
      internal UsageRecordConfiguration() {
        this.Ignore(ur => ur.EntityState);
        this.HasRequired(ur => ur.User).WithMany().HasForeignKey(ur => ur.UserId);
        this.HasRequired(ur => ur.Product).WithMany().HasForeignKey(ur => ur.ProductId);
      }
    }

    private class UserConfiguration : EntityTypeConfiguration<User> {
      internal UserConfiguration() {
        this.Ignore(u => u.EntityState);
        this.HasMany(u => u.PaymentInformation).WithRequired(pi => pi.User).HasForeignKey(pi => pi.UserId);
        this.HasRequired(u => u.ContactInformation).WithMany().HasForeignKey(u => u.ContactInformationId);
      }
    }

    #endregion

    #region DB Seed Methods

    // - DropCreateDatabaseAlways<BillingContext>
    // - DropCreateDatabaseIfModelChanges<BillingContext>
    public class BillingContextInitiliazer : DropCreateDatabaseAlways<BillingContext> {
      protected override void Seed(BillingContext context) {
        Product p1 = new Product() {
          Name = "OaaS Basic Service Charge",
          Description = "Create and run your experiments within HeuristicLab Hive",
          Price = 20.0,
          ProductType = "Optimization Service"
        };

        Product p2 = new Product() {
          Name = "Oaas Usage Charges",
          Description = "Charges for OaaS based on usage data",
          Price = 0.0,
          ProductType = "Optimization Service"
        };

        Product p3 = new Product() {
          Name = "Oaas Support Package",
          Description = "Charges for OaaS based on usage data",
          Price = 50.0,
          ProductType = "Optimization Service"
        };

        p1 = context.Products.Add(p1);
        p2 = context.Products.Add(p2);
        p3 = context.Products.Add(p3);

        User u1 = new Model.User() { Name = "spimming" };
        User u2 = new Model.User() {
          Name = "fschoeppl",
          PaymentInformation = new List<PaymentInformation>() { 
            new PaymentInformation() { 
              PaymentMethod = PaymentMethod.Visa, 
              CardNumber = "123456789" } }
        };

        u1 = context.Users.Add(u1);
        u2 = context.Users.Add(u2);

        ContactInformation ci1 = new ContactInformation() {
          FirstName = "Max",
          LastName = "Mustermann",
          Email = "max.mustermann@fh-hagenberg.at",
          OrganizationName = "University of Applied Sciences Upper Austria " + Environment.NewLine + "School of Informatics/Communications/Media",
          Street = "Softwarepark 11",
          PostalCode = "4232",
          City = "Hagenberg",
        };

        ci1 = context.ContactInformations.Add(ci1);
        u1.ContactInformation = ci1;

        ContactInformation ci2 = new ContactInformation() {
          FirstName = "Max",
          LastName = "Mustermann",
          Email = "max.mustermann@fh-hagenberg.at",
          OrganizationName = "University of Applied Sciences Upper Austria " + Environment.NewLine + "School of Informatics/Communications/Media",
          Street = "Softwarepark 11",
          PostalCode = "4232",
          City = "Hagenberg",
        };

        ci2 = context.ContactInformations.Add(ci2);
        u2.ContactInformation = ci2;

        Order o1 = new Order() {
          User = u2,
          State = OrderState.Created,
          BillingType = BillingType.Post,
          BillingPeriod = BillingPeriod.Monthly,
        };

        OrderLine ol1 = new OrderLine() {
          Order = o1,
          Product = p1,
          ProductPrice = p1.Price,
          Quantity = 1
        };

        o1 = context.Orders.Add(o1);
        ol1 = context.OrderLines.Add(ol1);

        context.SaveChanges();

        o1.State = OrderState.Active;
        o1.ActiveSince = DateTime.Now;
        context.Entry(o1).State = System.Data.EntityState.Modified;
        context.SaveChanges();
      }
    }

    #endregion
  }
}