using System;
using System.Collections.Generic;
using Server.Items;
using Server.Targeting;

namespace Server.SkillHandlers
{
    public static class Inscribe
    {
        private static readonly Dictionary<BaseBook, Mobile> m_UseTable = new();

        public static void Initialize()
        {
            SkillInfo.Table[(int)SkillName.Inscribe].Callback = OnUse;
        }

        public static TimeSpan OnUse(Mobile m)
        {
            Target target = new InternalTargetSrc();
            m.Target = target;
            m.SendLocalizedMessage(1046295); // Target the book you wish to copy.
            target.BeginTimeout(m, 60000); // 1 minute

            return TimeSpan.FromSeconds(1.0);
        }

        private static void SetUser(BaseBook book, Mobile mob)
        {
            m_UseTable[book] = mob;
        }

        private static void CancelUser(BaseBook book)
        {
            m_UseTable.Remove(book);
        }

        public static Mobile GetUser(BaseBook book)
        {
            m_UseTable.TryGetValue(book, out var m);
            return m;
        }

        public static bool IsEmpty(BaseBook book)
        {
            foreach (var page in book.Pages)
            {
                foreach (var line in page.Lines)
                {
                    if (!string.IsNullOrEmpty(line))
                    {
                        return false;
                    }
                }
            }

            return true;
        }

        public static void Copy(BaseBook bookSrc, BaseBook bookDst)
        {
            bookDst.Title = bookSrc.Title;
            bookDst.Author = bookSrc.Author;

            var pagesSrc = bookSrc.Pages;
            var pagesDst = bookDst.Pages;
            for (var i = 0; i < pagesSrc.Length && i < pagesDst.Length; i++)
            {
                var pageSrc = pagesSrc[i];
                var pageDst = pagesDst[i];

                var length = pageSrc.Lines.Length;
                pageDst.Lines = new string[length];

                for (var j = 0; j < length; j++)
                {
                    pageDst.Lines[j] = pageSrc.Lines[j];
                }
            }
        }

        private class InternalTargetSrc : Target
        {
            public InternalTargetSrc() : base(3, false, TargetFlags.None)
            {
            }

            protected override void OnTarget(Mobile from, object targeted)
            {
                if (targeted is not BaseBook book)
                {
                    from.SendLocalizedMessage(1046296); // That is not a book
                }
                else if (IsEmpty(book))
                {
                    from.SendLocalizedMessage(501611); // Can't copy an empty book.
                }
                else if (GetUser(book) != null)
                {
                    from.SendLocalizedMessage(501621); // Someone else is inscribing that item.
                }
                else
                {
                    Target target = new InternalTargetDst(book);
                    from.Target = target;
                    from.SendLocalizedMessage(501612); // Select a book to copy this to.
                    target.BeginTimeout(from, 60000); // 1 minute
                    SetUser(book, from);
                }
            }

            protected override void OnTargetCancel(Mobile from, TargetCancelType cancelType)
            {
                if (cancelType == TargetCancelType.Timeout)
                {
                    // You have waited too long to make your inscribe selection, your inscription attempt has timed out.
                    from.SendLocalizedMessage(501619);
                }
            }
        }

        private class InternalTargetDst : Target
        {
            private readonly BaseBook m_BookSrc;

            public InternalTargetDst(BaseBook bookSrc) : base(3, false, TargetFlags.None) => m_BookSrc = bookSrc;

            protected override void OnTarget(Mobile from, object targeted)
            {
                if (m_BookSrc.Deleted)
                {
                    return;
                }

                if (targeted is not BaseBook bookDst)
                {
                    from.SendLocalizedMessage(1046296); // That is not a book
                }
                else if (IsEmpty(m_BookSrc))
                {
                    from.SendLocalizedMessage(501611); // Can't copy an empty book.
                }
                else if (bookDst == m_BookSrc)
                {
                    from.SendLocalizedMessage(501616); // Cannot copy a book onto itself.
                }
                else if (!bookDst.Writable)
                {
                    from.SendLocalizedMessage(501614); // Cannot write into that book.
                }
                else if (GetUser(bookDst) != null)
                {
                    from.SendLocalizedMessage(501621); // Someone else is inscribing that item.
                }
                else
                {
                    if (from.CheckTargetSkill(SkillName.Inscribe, bookDst, 0, 50))
                    {
                        Copy(m_BookSrc, bookDst);

                        from.SendLocalizedMessage(501618); // You make a copy of the book.
                        from.PlaySound(0x249);
                    }
                    else
                    {
                        from.SendLocalizedMessage(501617); // You fail to make a copy of the book.
                    }
                }
            }

            protected override void OnTargetCancel(Mobile from, TargetCancelType cancelType)
            {
                if (cancelType == TargetCancelType.Timeout)
                {
                    // You have waited too long to make your inscribe selection, your inscription attempt has timed out.
                    from.SendLocalizedMessage(501619);
                }
            }

            protected override void OnTargetFinish(Mobile from)
            {
                CancelUser(m_BookSrc);
            }
        }
    }
}
