using MultiversalDiplomacy.Adjudicate;
using MultiversalDiplomacy.Model;
using MultiversalDiplomacy.Orders;

namespace MultiversalDiplomacy;

/// <summary>
/// The game controller is a stateless class that defines the basic, high-level operations that can be taken to modify
/// the game state.
/// </summary>
public static class GameController
{
    public static World InitializeWorld()
    {
        return World.Standard;
    }

    public static World SubmitOrderSet(World world, string text)
    {
        var orderSet = new OrderSet(text);
        return world.Update(orderSets: world.OrderSets.Append(orderSet));
    }

    public static World AdjudicateOrders(World world)
    {
        // Determine which phase the game is in, which determines how orders should be interpreted and adjudicated.
        PhaseType phaseType = world.GetNextPhaseType();

        IPhaseAdjudicator adjudicator = phaseType switch {
            PhaseType.Movement => MovementPhaseAdjudicator.Instance,
            PhaseType.Retreat => throw new NotImplementedException(),
            PhaseType.Build => throw new NotImplementedException(),
            PhaseType.Sustain => throw new NotImplementedException(),
            _ => throw new InvalidOperationException(phaseType.ToString()),
        };

        // Parse the order sets into actual orders.
        List<Order> parsedOrders = adjudicator.ParseOrderSets(world, world.OrderSets.ToList());

        // Validate the orders.
        var orderValidations = adjudicator.ValidateOrders(world, parsedOrders);

        // Adjudicate the orders.
        var validOrders = orderValidations.Where(v => v.Valid).Select(v => v.Order).ToList();
        var results = adjudicator.AdjudicateOrders(world, validOrders);

        // Update the world.
        return adjudicator.UpdateWorld(world, results);
    }
}