using System;
using System.Collections.Generic;
using RobotAndDonkey.Game.Execution.Results;
using RobotAndDonkey.Game.GameState;
using RobotAndDonkey.Game.Intents;
using RobotAndDonkey.Game.Modifiers;
using RobotAndDonkey.Game.Pois;

namespace RobotAndDonkey.Game.Execution.Commands;

public abstract record Command(Guid RequestId, params Type[] RequestTypes)
{
    protected abstract void CreateIntents(CoreLoop coreLoop, List<Intent> intents);

    public List<Result> Preview(CoreLoop coreLoop)
    {
        var mockCoreLoop = new CoreLoop(coreLoop) { IsPreview = true };
        return Execute(mockCoreLoop, false, false);
    }

    public List<Result> Execute(CoreLoop coreLoop, bool force, bool verbose)
    {
        var results = new List<Result>();
        var intents = new List<Intent>();
        CreateIntents(coreLoop, intents);

        var modifiers = GetModifierStack(coreLoop);
        modifiers.Execute(RequestId, coreLoop, intents, results, force, verbose);
        return results;
    }

    private static ModifierStack GetModifierStack(CoreLoop coreLoop)
    {
        var modifiers = new ModifierStack();
        modifiers.Push(coreLoop.Robot);
    
        foreach (var cell in coreLoop.Board.Cells)
        {
            if (cell.Poi is Avatar)
            {
                modifiers.Push(cell);
            }
        }

        return modifiers;
    }

    public bool IsValid(CoreLoop coreLoop, out EInvalidReason reason)
    {
        var results = Preview(coreLoop);
        if (results.Count == 0)
        {
            reason = EInvalidReason.Invariant;
            return false;
        }

        if (results is [InvalidInstructionResult])
        {
            reason = EInvalidReason.Invalid;
            return false;
        }
        
        reason = (EInvalidReason)(-1);
        return true;
    }

    public int EstimateEnergyCost(CoreLoop coreLoop)
    {
        var results = Preview(coreLoop);
        if (results.Count == 0)
            return 0;

        var newEnergy = 0;
        foreach (var result in results)
        {
            if (result is CurrencyResult currencyResult)
                newEnergy = currencyResult.NewCurrency.Energy;
        }

        return coreLoop.Currency.Energy - newEnergy;
    }
}