using Collaboration.Domain.Entities;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata.Builders;

namespace Collaboration.Infrastructure.Persistence;

/// <summary>
/// DbContext for the Collaboration module.
/// Designed to be registered as a separate context or merged into your
/// main application DbContext — your choice based on deployment preference.
/// </summary>
public class CollabDbContext : DbContext
{
    public CollabDbContext(DbContextOptions<CollabDbContext> options) : base(options) { }

    public DbSet<CollabSession> Sessions => Set<CollabSession>();
    public DbSet<CollabParticipant> Participants => Set<CollabParticipant>();
    public DbSet<CollabSessionInvite> Invites => Set<CollabSessionInvite>();
    public DbSet<CollabSessionEvent> SessionEvents => Set<CollabSessionEvent>();
    public DbSet<CollabConfig> Configs => Set<CollabConfig>();

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.HasDefaultSchema("collab");

        modelBuilder.ApplyConfiguration(new CollabSessionConfiguration());
        modelBuilder.ApplyConfiguration(new CollabParticipantConfiguration());
        modelBuilder.ApplyConfiguration(new CollabSessionInviteConfiguration());
        modelBuilder.ApplyConfiguration(new CollabSessionEventConfiguration());
        modelBuilder.ApplyConfiguration(new CollabConfigConfiguration());
    }
}


// ── Entity Configurations ────────────────────────────────────────────────────

internal class CollabSessionConfiguration : IEntityTypeConfiguration<CollabSession>
{
    public void Configure(EntityTypeBuilder<CollabSession> b)
    {
        b.ToTable("Sessions");
        b.HasKey(x => x.SessionId);

        b.Property(x => x.SessionCode).HasMaxLength(10).IsRequired();
        b.HasIndex(x => x.SessionCode).IsUnique();

        b.Property(x => x.Title).HasMaxLength(200).IsRequired();
        b.Property(x => x.SessionType).HasConversion<string>().HasMaxLength(20);
        b.Property(x => x.Status).HasConversion<string>().HasMaxLength(20);
        b.Property(x => x.Mode).HasConversion<string>().HasMaxLength(20);

        b.Property(x => x.ContextModuleCode).HasMaxLength(50);
        b.Property(x => x.ContextRecordId).HasMaxLength(100);
        b.Property(x => x.ContextRecordLabel).HasMaxLength(300);
        b.Property(x => x.ContextRouteUrl).HasMaxLength(1000);

        b.Property(x => x.SettingsJson).HasColumnType("nvarchar(max)");

        // Indexes for common query patterns
        b.HasIndex(x => new { x.OrgId, x.Status });
        b.HasIndex(x => new { x.CreatedBy, x.Status });
        b.HasIndex(x => x.ScheduledAt);

        b.HasMany(x => x.Participants)
            .WithOne(x => x.Session)
            .HasForeignKey(x => x.SessionId)
            .OnDelete(DeleteBehavior.Cascade);

        b.HasMany(x => x.Invites)
            .WithOne(x => x.Session)
            .HasForeignKey(x => x.SessionId)
            .OnDelete(DeleteBehavior.Cascade);

        b.HasMany(x => x.Events)
            .WithOne(x => x.Session)
            .HasForeignKey(x => x.SessionId)
            .OnDelete(DeleteBehavior.Cascade);
    }
}

internal class CollabParticipantConfiguration : IEntityTypeConfiguration<CollabParticipant>
{
    public void Configure(EntityTypeBuilder<CollabParticipant> b)
    {
        b.ToTable("Participants");
        b.HasKey(x => x.ParticipantId);

        b.Property(x => x.DisplayName).HasMaxLength(150).IsRequired();
        b.Property(x => x.Role).HasConversion<string>().HasMaxLength(20);
        b.Property(x => x.CursorColor).HasMaxLength(7); // hex #RRGGBB
        b.Property(x => x.SignalRConnectionId).HasMaxLength(200);

        b.HasIndex(x => new { x.SessionId, x.UserId });
        b.HasIndex(x => x.SignalRConnectionId);  // Needed for disconnect lookup
    }
}

internal class CollabSessionInviteConfiguration : IEntityTypeConfiguration<CollabSessionInvite>
{
    public void Configure(EntityTypeBuilder<CollabSessionInvite> b)
    {
        b.ToTable("Invites");
        b.HasKey(x => x.InviteId);

        b.Property(x => x.InviteToken).HasMaxLength(100).IsRequired();
        b.HasIndex(x => x.InviteToken).IsUnique();

        b.Property(x => x.OfferedRole).HasConversion<string>().HasMaxLength(20);
        b.Property(x => x.Status).HasConversion<string>().HasMaxLength(20);

        b.HasIndex(x => new { x.SessionId, x.InvitedUserId });
        b.HasIndex(x => x.ExpiresAt);   // For expiry cleanup job
    }
}

internal class CollabSessionEventConfiguration : IEntityTypeConfiguration<CollabSessionEvent>
{
    public void Configure(EntityTypeBuilder<CollabSessionEvent> b)
    {
        b.ToTable("SessionEvents");
        b.HasKey(x => x.EventId);
        b.Property(x => x.EventId).UseIdentityColumn();

        b.Property(x => x.EventType).HasConversion<string>().HasMaxLength(50);
        b.Property(x => x.Payload).HasColumnType("nvarchar(max)");

        b.HasIndex(x => new { x.SessionId, x.Timestamp });
        b.HasIndex(x => new { x.EventType, x.Timestamp }); // Audit queries
    }
}

internal class CollabConfigConfiguration : IEntityTypeConfiguration<CollabConfig>
{
    public void Configure(EntityTypeBuilder<CollabConfig> b)
    {
        b.ToTable("Configs");
        b.HasKey(x => x.OrgId);

        b.Property(x => x.ControlConsentMode).HasConversion<string>().HasMaxLength(30);
        b.Property(x => x.AllowedModulesJson).HasColumnType("nvarchar(max)");
    }
}