using System;
using System.Collections.Generic;
using System.Text;
using Server.Commands;
using Server.Gumps;
using Server.Items;
using Server.Network;
using Server.Prompts;

namespace Server.Mobiles
{
  public interface ITownCrierEntryList
  {
    List<TownCrierEntry> Entries{ get; }
    TownCrierEntry GetRandomEntry();
    TownCrierEntry AddEntry(string[] lines, TimeSpan duration);
    void RemoveEntry(TownCrierEntry entry);
  }

  public class GlobalTownCrierEntryList : ITownCrierEntryList
  {
    private static GlobalTownCrierEntryList m_Instance;

    public static GlobalTownCrierEntryList Instance => m_Instance ?? (m_Instance = new GlobalTownCrierEntryList());

    public bool IsEmpty => Entries == null || Entries.Count == 0;

    public List<TownCrierEntry> Entries{ get; private set; }

    public TownCrierEntry GetRandomEntry()
    {
      if (Entries == null || Entries.Count == 0)
        return null;

      for (int i = Entries.Count - 1; Entries != null && i >= 0; --i)
      {
        if (i >= Entries.Count)
          continue;

        TownCrierEntry tce = Entries[i];

        if (tce.Expired)
          RemoveEntry(tce);
      }

      if (Entries == null || Entries.Count == 0)
        return null;

      return Entries[Utility.Random(Entries.Count)];
    }

    public TownCrierEntry AddEntry(string[] lines, TimeSpan duration)
    {
      if (Entries == null)
        Entries = new List<TownCrierEntry>();

      TownCrierEntry tce = new TownCrierEntry(lines, duration);

      Entries.Add(tce);

      List<TownCrier> instances = TownCrier.Instances;

      for (int i = 0; i < instances.Count; ++i)
        instances[i].ForceBeginAutoShout();

      return tce;
    }

    public void RemoveEntry(TownCrierEntry tce)
    {
      if (Entries == null)
        return;

      Entries.Remove(tce);

      if (Entries.Count == 0)
        Entries = null;
    }

    public static void Initialize()
    {
      CommandSystem.Register("TownCriers", AccessLevel.GameMaster, TownCriers_OnCommand);
    }

    [Usage("TownCriers")]
    [Description("Manages the global town crier list.")]
    public static void TownCriers_OnCommand(CommandEventArgs e)
    {
      e.Mobile.SendGump(new TownCrierGump(e.Mobile, Instance));
    }
  }

  public class TownCrierEntry
  {
    public TownCrierEntry(string[] lines, TimeSpan duration)
    {
      Lines = lines;

      if (duration < TimeSpan.Zero)
        duration = TimeSpan.Zero;
      else if (duration > TimeSpan.FromDays(365.0))
        duration = TimeSpan.FromDays(365.0);

      ExpireTime = DateTime.UtcNow + duration;
    }

    public string[] Lines{ get; }

    public DateTime ExpireTime{ get; }

    public bool Expired => DateTime.UtcNow >= ExpireTime;
  }

  public class TownCrierDurationPrompt : Prompt
  {
    private ITownCrierEntryList m_Owner;

    public TownCrierDurationPrompt(ITownCrierEntryList owner)
    {
      m_Owner = owner;
    }

    public override void OnResponse(Mobile from, string text)
    {
      if (!TimeSpan.TryParse(text, out TimeSpan ts))
      {
        from.SendMessage("Value was not properly formatted. Use: <hours:minutes:seconds>");
        from.SendGump(new TownCrierGump(from, m_Owner));
        return;
      }

      if (ts < TimeSpan.Zero)
        ts = TimeSpan.Zero;

      from.SendMessage("Duration set to: {0}", ts);
      from.SendMessage("Enter the first line to shout:");

      from.Prompt = new TownCrierLinesPrompt(m_Owner, null, new List<string>(), ts);
    }

    public override void OnCancel(Mobile from)
    {
      from.SendLocalizedMessage(502980); // Message entry cancelled.
      from.SendGump(new TownCrierGump(from, m_Owner));
    }
  }

  public class TownCrierLinesPrompt : Prompt
  {
    private TimeSpan m_Duration;
    private TownCrierEntry m_Entry;
    private List<string> m_Lines;
    private ITownCrierEntryList m_Owner;

    public TownCrierLinesPrompt(ITownCrierEntryList owner, TownCrierEntry entry, List<string> lines, TimeSpan duration)
    {
      m_Owner = owner;
      m_Entry = entry;
      m_Lines = lines;
      m_Duration = duration;
    }

    public override void OnResponse(Mobile from, string text)
    {
      m_Lines.Add(text);

      from.SendMessage("Enter the next line to shout, or press <ESC> if the message is finished.");
      from.Prompt = new TownCrierLinesPrompt(m_Owner, m_Entry, m_Lines, m_Duration);
    }

    public override void OnCancel(Mobile from)
    {
      if (m_Entry != null)
        m_Owner.RemoveEntry(m_Entry);

      if (m_Lines.Count > 0)
      {
        m_Owner.AddEntry(m_Lines.ToArray(), m_Duration);
        from.SendMessage("Message has been set.");
      }
      else
      {
        if (m_Entry != null)
          from.SendMessage("Message deleted.");
        else
          from.SendLocalizedMessage(502980); // Message entry cancelled.
      }

      from.SendGump(new TownCrierGump(from, m_Owner));
    }
  }

  public class TownCrierGump : Gump
  {
    private Mobile m_From;
    private ITownCrierEntryList m_Owner;

    public TownCrierGump(Mobile from, ITownCrierEntryList owner) : base(50, 50)
    {
      m_From = from;
      m_Owner = owner;

      from.CloseGump<TownCrierGump>();

      AddPage(0);

      List<TownCrierEntry> entries = owner.Entries;

      owner.GetRandomEntry(); // force expiration checks

      int count = 0;

      if (entries != null)
        count = entries.Count;

      AddImageTiled(0, 0, 300, 38 + (count == 0 ? 20 : count * 85), 0xA40);
      AddAlphaRegion(1, 1, 298, 36 + (count == 0 ? 20 : count * 85));

      AddHtml(8, 8, 300 - 8 - 30, 20, "<basefont color=#FFFFFF><center>TOWN CRIER MESSAGES</center></basefont>");

      AddButton(300 - 8 - 30, 8, 0xFAB, 0xFAD, 1);

      if (count == 0)
        AddHtml(8, 30, 284, 20, "<basefont color=#FFFFFF>The crier has no news.</basefont>");
      else
        for (int i = 0; i < entries.Count; ++i)
        {
          TownCrierEntry tce = entries[i];

          TimeSpan toExpire = tce.ExpireTime - DateTime.UtcNow;

          if (toExpire < TimeSpan.Zero)
            toExpire = TimeSpan.Zero;

          StringBuilder sb = new StringBuilder();

          sb.Append("[Expires: ");

          if (toExpire.TotalHours >= 1)
          {
            sb.Append((int)toExpire.TotalHours);
            sb.Append(':');
            sb.Append(toExpire.Minutes.ToString("D2"));
          }
          else
          {
            sb.Append(toExpire.Minutes);
          }

          sb.Append(':');
          sb.Append(toExpire.Seconds.ToString("D2"));

          sb.Append("] ");

          for (int j = 0; j < tce.Lines.Length; ++j)
          {
            if (j > 0)
              sb.Append("<br>");

            sb.Append(tce.Lines[j]);
          }

          AddHtml(8, 35 + i * 85, 254, 80, sb.ToString(), true, true);

          AddButton(300 - 8 - 26, 35 + i * 85, 0x15E1, 0x15E5, 2 + i);
        }
    }

    public override void OnResponse(NetState sender, RelayInfo info)
    {
      if (info.ButtonID == 1)
      {
        m_From.SendMessage("Enter the duration for the new message. Format: <hours:minutes:seconds>");
        m_From.Prompt = new TownCrierDurationPrompt(m_Owner);
      }
      else if (info.ButtonID > 1)
      {
        List<TownCrierEntry> entries = m_Owner.Entries;
        int index = info.ButtonID - 2;

        if (entries != null && index < entries.Count)
        {
          TownCrierEntry tce = entries[index];
          TimeSpan ts = tce.ExpireTime - DateTime.UtcNow;

          if (ts < TimeSpan.Zero)
            ts = TimeSpan.Zero;

          m_From.SendMessage("Editing entry #{0}.", index + 1);
          m_From.SendMessage("Enter the first line to shout:");
          m_From.Prompt = new TownCrierLinesPrompt(m_Owner, tce, new List<string>(), ts);
        }
      }
    }
  }

  public class TownCrier : Mobile, ITownCrierEntryList
  {
    private Timer m_AutoShoutTimer;
    private Timer m_NewsTimer;

    [Constructible]
    public TownCrier()
    {
      Instances.Add(this);

      InitStats(100, 100, 25);

      Title = "the town crier";
      Hue = Race.Human.RandomSkinHue();

      if (!Core.AOS)
        NameHue = 0x35;

      if (Female = Utility.RandomBool())
      {
        Body = 0x191;
        Name = NameList.RandomName("female");
      }
      else
      {
        Body = 0x190;
        Name = NameList.RandomName("male");
      }

      AddItem(new FancyShirt(Utility.RandomBlueHue()));

      Item skirt;

      switch (Utility.Random(2))
      {
        case 0:
          skirt = new Skirt();
          break;
        default:
        case 1:
          skirt = new Kilt();
          break;
      }

      skirt.Hue = Utility.RandomGreenHue();

      AddItem(skirt);

      AddItem(new FeatheredHat(Utility.RandomGreenHue()));

      Item boots;

      switch (Utility.Random(2))
      {
        case 0:
          boots = new Boots();
          break;
        default:
        case 1:
          boots = new ThighBoots();
          break;
      }

      AddItem(boots);

      Utility.AssignRandomHair(this);
    }

    public TownCrier(Serial serial) : base(serial)
    {
      Instances.Add(this);
    }

    public static List<TownCrier> Instances{ get; } = new List<TownCrier>();

    public List<TownCrierEntry> Entries{ get; private set; }

    public TownCrierEntry GetRandomEntry()
    {
      if (Entries == null || Entries.Count == 0)
        return GlobalTownCrierEntryList.Instance.GetRandomEntry();

      for (int i = Entries.Count - 1; Entries != null && i >= 0; --i)
      {
        if (i >= Entries.Count)
          continue;

        TownCrierEntry tce = Entries[i];

        if (tce.Expired)
          RemoveEntry(tce);
      }

      if (Entries == null || Entries.Count == 0)
        return GlobalTownCrierEntryList.Instance.GetRandomEntry();

      TownCrierEntry entry = GlobalTownCrierEntryList.Instance.GetRandomEntry();

      if (entry == null || Utility.RandomBool())
        entry = Entries[Utility.Random(Entries.Count)];

      return entry;
    }

    public TownCrierEntry AddEntry(string[] lines, TimeSpan duration)
    {
      if (Entries == null)
        Entries = new List<TownCrierEntry>();

      TownCrierEntry tce = new TownCrierEntry(lines, duration);

      Entries.Add(tce);

      if (m_AutoShoutTimer == null)
        m_AutoShoutTimer = Timer.DelayCall(TimeSpan.FromSeconds(5.0), TimeSpan.FromMinutes(1.0), AutoShout_Callback);

      return tce;
    }

    public void RemoveEntry(TownCrierEntry tce)
    {
      if (Entries == null)
        return;

      Entries.Remove(tce);

      if (Entries.Count == 0)
        Entries = null;

      if (Entries == null && GlobalTownCrierEntryList.Instance.IsEmpty)
      {
        m_AutoShoutTimer?.Stop();

        m_AutoShoutTimer = null;
      }
    }

    public void ForceBeginAutoShout()
    {
      if (m_AutoShoutTimer == null)
        m_AutoShoutTimer = Timer.DelayCall(TimeSpan.FromSeconds(5.0), TimeSpan.FromMinutes(1.0), AutoShout_Callback);
    }

    private void AutoShout_Callback()
    {
      TownCrierEntry tce = GetRandomEntry();

      if (tce == null)
      {
        m_AutoShoutTimer?.Stop();

        m_AutoShoutTimer = null;
      }
      else if (m_NewsTimer == null)
      {
        int index = 0;
        m_NewsTimer = Timer.DelayCall(TimeSpan.FromSeconds(1.0), TimeSpan.FromSeconds(3.0),
          () => ShoutNews_Callback(tce, index));

        PublicOverheadMessage(MessageType.Regular, 0x3B2, 502976); // Hear ye! Hear ye!
      }
    }

    private void ShoutNews_Callback(TownCrierEntry tce, int index)
    {
      if (index < 0 || index >= tce.Lines.Length)
      {
        m_NewsTimer?.Stop();
        m_NewsTimer = null;
      }
      else
      {
        PublicOverheadMessage(MessageType.Regular, 0x3B2, false, tce.Lines[index]);
      }
    }

    public override void OnDoubleClick(Mobile from)
    {
      if (from.AccessLevel >= AccessLevel.GameMaster)
        from.SendGump(new TownCrierGump(from, this));
      else
        base.OnDoubleClick(from);
    }

    public override bool HandlesOnSpeech(Mobile from)
    {
      return m_NewsTimer == null && from.Alive && InRange(from, 12);
    }

    public override void OnSpeech(SpeechEventArgs e)
    {
      if (m_NewsTimer == null && e.HasKeyword(0x30) && e.Mobile.Alive && InRange(e.Mobile, 12)) // *news*
      {
        Direction = GetDirectionTo(e.Mobile);

        TownCrierEntry tce = GetRandomEntry();

        if (tce == null)
        {
          PublicOverheadMessage(MessageType.Regular, 0x3B2, 1005643); // I have no news at this time.
        }
        else
        {
          int index = 0;
          m_NewsTimer = Timer.DelayCall(TimeSpan.FromSeconds(1.0), TimeSpan.FromSeconds(3.0),
            () => ShoutNews_Callback(tce, index));

          PublicOverheadMessage(MessageType.Regular, 0x3B2, 502978); // Some of the latest news!
        }
      }
    }

    public override bool CanBeDamaged()
    {
      return false;
    }

    public override void OnDelete()
    {
      Instances.Remove(this);
      base.OnDelete();
    }

    public override void Serialize(GenericWriter writer)
    {
      base.Serialize(writer);

      writer.Write(0); // version
    }

    public override void Deserialize(GenericReader reader)
    {
      base.Deserialize(reader);

      int version = reader.ReadInt();

      if (Core.AOS && NameHue == 0x35)
        NameHue = -1;
    }
  }
}