blazor-swm/Infrastructure/Database/Demo/BookingSeeder.cs

using Indotalent.ConfigBackEnd.Extensions;
using Indotalent.Data.Entities;
using Indotalent.Data.Enums;
using Microsoft.EntityFrameworkCore;

namespace Indotalent.Infrastructure.Database.Demo;

public static class BookingSeeder
{
    public static async Task GenerateDataAsync(AppDbContext context)
    {
        if (await context.Booking.AnyAsync()) return;

        var random = new Random();
        var bookingStatusValues = Enum.GetValues(typeof(BookingStatus)).Cast<BookingStatus>().ToList();
        var entityName = nameof(Booking);

        var dateEnd = DateTime.Now;
        var dateStart = dateEnd.AddMonths(-12);

        var bookingResources = await context.BookingResource
            .Select(x => x.Id)
            .ToListAsync();

        var locations = await context.Warehouse
            .Where(x => x.SystemWarehouse == false)
            .Select(x => x.Name)
            .ToListAsync();

        if (!bookingResources.Any() || !locations.Any()) return;

        for (DateTime date = dateStart; date < dateEnd; date = date.AddMonths(1))
        {
            DateTime[] transactionDates = GenerateRandomDays(date.Year, date.Month, 25);
            foreach (DateTime transDate in transactionDates)
            {
                int hourStart = random.Next(8, 18);
                DateTime startTime = transDate.Date.AddHours(hourStart);

                var autoNo = await context.GenerateAutoNumberAsync(
                    entityName: entityName,
                    prefixTemplate: $"{entityName.ToShortNameConsonant(3)}/{{Year}}/"
                );

                var booking = new Booking
                {
                    Subject = $"Appointment {autoNo}",
                    AutoNumber = autoNo,
                    StartTime = startTime,
                    EndTime = startTime.AddHours(random.Next(1, 3)),
                    BookingResourceId = GetRandomValue(bookingResources, random),
                    Status = bookingStatusValues[random.Next(bookingStatusValues.Count)],
                    Location = GetRandomValue(locations, random)
                };

                await context.Booking.AddAsync(booking);
            }
        }

        await context.SaveChangesAsync();
    }

    private static DateTime[] GenerateRandomDays(int year, int month, int count)
    {
        var random = new Random();
        int daysInMonthCount = DateTime.DaysInMonth(year, month);
        return Enumerable.Range(1, count)
            .Select(_ => new DateTime(year, month, random.Next(1, daysInMonthCount + 1)))
            .ToArray();
    }

    private static T GetRandomValue<T>(List<T> list, Random random)
    {
        return list[random.Next(list.Count)];
    }
}