using System;
using System.Linq;
using Server.Gumps;
using Server.Items;
using Server.Mobiles;

namespace Server.Engines.MLQuests.Objectives
{
  public class CollectObjective : BaseObjective
  {
    public CollectObjective(int amount = 0, Type type = null, TextDefinition name = null)
    {
      DesiredAmount = amount;
      AcceptedType = type;
      Name = name;

      if (MLQuestSystem.Debug && ShowDetailed && name.Number > 0)
      {
        int itemid = LabelToItemID(name.Number);

        if (itemid <= 0 || itemid > 0x4000)
          Console.WriteLine("Warning: cliloc {0} is likely giving the wrong item ID", name.Number);
      }
    }

    public int DesiredAmount{ get; set; }

    public Type AcceptedType{ get; set; }

    public TextDefinition Name{ get; set; }

    public virtual bool ShowDetailed => true;

    public bool CheckType(Type type) => AcceptedType?.IsAssignableFrom(type) == true;

    public virtual bool CheckItem(Item item) => true;

    public static int LabelToItemID(int label)
    {
      if (label < 1078872)
        return label - 1020000;
      return label - 1078872;
    }

    public override void WriteToGump(Gump g, ref int y)
    {
      if (ShowDetailed)
      {
        string amount = DesiredAmount.ToString();

        g.AddHtmlLocalized(98, y, 350, 16, 1072205, 0x15F90); // Obtain
        g.AddLabel(143, y, 0x481, amount);

        if (Name.Number > 0)
        {
          g.AddHtmlLocalized(143 + amount.Length * 15, y, 190, 18, Name.Number, 0x77BF);
          g.AddItem(350, y, LabelToItemID(Name.Number));
        }
        else if (Name.String != null)
        {
          g.AddLabel(143 + amount.Length * 15, y, 0x481, Name.String);
        }
      }
      else
      {
        if (Name.Number > 0)
          g.AddHtmlLocalized(98, y, 312, 32, Name.Number, 0x15F90);
        else if (Name.String != null)
          g.AddLabel(98, y, 0x481, Name.String);
      }

      y += 32;
    }

    public override BaseObjectiveInstance CreateInstance(MLQuestInstance instance) => new CollectObjectiveInstance(this, instance);
  }

  #region Timed

  public class TimedCollectObjective : CollectObjective
  {
    public TimedCollectObjective(TimeSpan duration, int amount, Type type, TextDefinition name)
      : base(amount, type, name) =>
      Duration = duration;

    public override bool IsTimed => true;
    public override TimeSpan Duration{ get; }
  }

  #endregion

  public class CollectObjectiveInstance : BaseObjectiveInstance
  {
    public CollectObjectiveInstance(CollectObjective objective, MLQuestInstance instance)
      : base(instance, objective) =>
      Objective = objective;

    public CollectObjective Objective{ get; set; }

    private int GetCurrentTotal()
    {
      Container pack = Instance.Player.Backpack;

      if (pack == null)
        return 0;

      Item[] items = pack.FindItemsByType(Objective.AcceptedType, false); // Note: subclasses are included
      return items.Where(item => item.QuestItem && Objective.CheckItem(item)).Sum(item => item.Amount);
    }

    public override bool AllowsQuestItem(Item item, Type type) => Objective.CheckType(type) && Objective.CheckItem(item);

    public override bool IsCompleted() => GetCurrentTotal() >= Objective.DesiredAmount;

    public override void OnQuestCancelled()
    {
      PlayerMobile pm = Instance.Player;
      Container pack = pm.Backpack;

      if (pack == null)
        return;

      Type checkType = Objective.AcceptedType;
      Item[] items = pack.FindItemsByType(checkType, false);

      foreach (Item item in items)
        if (item.QuestItem && !MLQuestSystem.CanMarkQuestItem(pm, item, checkType)
        ) // does another quest still need this item? (OSI just unmarks everything)
          item.QuestItem = false;
    }

    // Should only be called after IsComplete() is checked to be true
    public override void OnClaimReward()
    {
      Container pack = Instance.Player.Backpack;

      if (pack == null)
        return;

      // TODO: OSI also counts the item in the cursor?

      Item[] items = pack.FindItemsByType(Objective.AcceptedType, false);
      int left = Objective.DesiredAmount;

      foreach (Item item in items)
        if (item.QuestItem && Objective.CheckItem(item))
        {
          if (left == 0)
            return;

          if (item.Amount > left)
          {
            item.Consume(left);
            left = 0;
          }
          else
          {
            item.Delete();
            left -= item.Amount;
          }
        }
    }

    public override void OnAfterClaimReward()
    {
      OnQuestCancelled(); // same thing, clear other quest items
    }

    public override void OnExpire()
    {
      OnQuestCancelled();

      // No message
    }

    public override void WriteToGump(Gump g, ref int y)
    {
      Objective.WriteToGump(g, ref y);
      y -= 16;

      if (Objective.ShowDetailed)
      {
        base.WriteToGump(g, ref y);

        g.AddHtmlLocalized(103, y, 120, 16, 3000087, 0x15F90); // Total
        g.AddLabel(223, y, 0x481, GetCurrentTotal().ToString());
        y += 16;

        g.AddHtmlLocalized(103, y, 120, 16, 1074782, 0x15F90); // Return to
        g.AddLabel(223, y, 0x481, QuesterNameAttribute.GetQuesterNameFor(Instance.QuesterType));
        y += 16;
      }
    }
  }
}