using Microsoft.EntityFrameworkCore;
using UtopiaCanteenSystem.Models;
using System.IO;

namespace UtopiaCanteenSystem.Data;

/// <summary>
/// SQLite DbContext for Labour and ScanRecord tables.
/// Database file is created in application directory on first run.
/// </summary>
public class AppDbContext : DbContext
{
    private static readonly string DbPath = Path.Combine(
        AppDomain.CurrentDomain.BaseDirectory,
        "utopia_canteen.db");

    public DbSet<Labour> Labour { get; set; }
    public DbSet<ScanRecord> ScanRecords { get; set; }

    public AppDbContext() { }

    public AppDbContext(DbContextOptions<AppDbContext> options) : base(options) { }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        if (!optionsBuilder.IsConfigured)
            optionsBuilder.UseSqlite($"Data Source={DbPath}");
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        // Labour: CardId should be indexed for lookups.
        modelBuilder.Entity<Labour>(e =>
        {
            e.HasKey(x => x.Id);
            e.HasIndex(x => x.CardId);
        });

        // ScanRecord: Index for unsynced queries and by ScanTime.
        modelBuilder.Entity<ScanRecord>(e =>
        {
            e.HasKey(x => x.Id);
            e.HasIndex(x => x.IsSynced);
            e.HasIndex(x => x.ScanTime);
        });
    }

    /// <summary>
    /// Ensures database exists and is migrated. Call on app startup.
    /// </summary>
    public void EnsureDatabaseCreated()
    {
        Database.EnsureCreated();
    }
}