using FastEndpoints;
using FluentValidation;
using Microsoft.EntityFrameworkCore;
using MissionControl.Data;
using MissionControl.Domain.Entities;

namespace MissionControl.Server.Endpoints.Missions.MissionLaunches;

public class CreateMissionLaunch(MissionControlContext dbContext)
    : Endpoint<CreateMissionLaunchRequest, MissionLaunchResponse>
{
    public override void Configure()
    {
        Post("/missions/{MissionId}/launch");
    }

    public override async Task HandleAsync(CreateMissionLaunchRequest req, CancellationToken ct)
    {
        var missionExists = await dbContext.Missions.AnyAsync(mission => mission.Id == req.MissionId, ct);
        if (!missionExists)
        {
            await Send.NotFoundAsync(ct);
            return;
        }

        var missionLaunch = new MissionLaunch
        {
            ScheduledFor = req.ScheduledFor,
            // Validated in `CreateMissionLaunchRequestValidator`
            Status = Enum.Parse<MissionLaunchStatus>(req.Status, true),
            MissionId = req.MissionId,
        };

        dbContext.MissionLaunches.Add(missionLaunch);
        await dbContext.SaveChangesAsync(ct);

        await Send.OkAsync(MissionLaunchResponse.FromDomain(missionLaunch), ct);
    }
}

public record CreateMissionLaunchRequest
{
    public Guid MissionId { get; init; }
    public required DateTimeOffset ScheduledFor { get; init; }

    // Define as a string here so it can be safely deserialized into its enum type, with a validation message when unable to do so
    // Otherwise, we return a serialization error that is not assigned to a specific field
    public required string Status { get; init; }
}

public class CreateMissionLaunchRequestValidator : Validator<CreateMissionLaunchRequest>
{
    public CreateMissionLaunchRequestValidator()
    {
        RuleFor(req => req.MissionId)
            .NotEqual(Guid.Empty)
            .WithMessage("Please provide a non-zero GUID.");
        RuleFor(req => req.Status).IsEnumName(typeof(MissionLaunchStatus), false);
    }
}