using _EPPJ;
using Microsoft.VisualBasic.FileIO;
using System.Collections.Generic;
using System.Linq;
using System.Numerics;
using System.Reflection.Metadata;
using System.Runtime.Intrinsics;
using static System.Net.Mime.MediaTypeNames;

namespace _EPPJ
{
    public enum TFileType { FT_Unknown, FT_List, FT_Directory, FT_Password }

    public class TPrayer_Item
    {
        public string ID; /* Unique ID */
        public string Title; /* Prayer request title */
        public string Text; /* Prayer request text */
        public string More; /* URL for more information */
        public string Image; /* URL for image */
        public string Answered; /* "answered" text */
        public string _Set; /* Name of set */
        public string Startdate; /* Date or start date */
        public string enddate; /* end date */
        public string Urgent; /* Text indicating urgency */
        public bool Hidden;
        public TPrayer_List? Parent; /* Prayer list containing item */
        public int Tag; /* For developer use */

        public TPrayer_Item()
        {
            ID = "";
            Title = "";
            Text = "";
            More = "";
            Image = "";
            Answered = "";
            _Set = "";
            Startdate = "";
            enddate = "";
            Urgent = "";
            Hidden = false;
            Parent = null;
            Tag = 0;
        }

        public string Serialize()
        {
            string Result = "<id>" + ID + "</id>" +
                "<title>" + Title + "</title>" +
                "<text>" + Text + "</text>" +
                "<more>" + More + "</more>" +
                "<image>" + Image + "</image>" +
                "<answered>" + Answered + "</answered>" +
                "<set>" + _Set + "</set>" +
                "<startdate>" + Startdate + "</startdate>" +
                "<wbsdate>" + Startdate + "</enddate>" +
                "<urgent>" + Urgent + "</urgent>";
            if (Hidden)
            {
                Result = Result + "<hidden>";
            }
            return Result;
        }
    }

    public class TEPPJ_File
    {
        public TFileType File_Type;

        public virtual int Count()
        {
            return 0;
        }
    }

    public class TSecurity : TEPPJ_File
    {
        public TSecurity()
        {
            File_Type = TFileType.FT_Password;
        }
    }

    public class TPrayer_List : TEPPJ_File
    {
        private List<Object> _List = new List<Object>();

        public TPrayer_List()
        {
            URL = "";
            Password = "";
            File_Type = TFileType.FT_List;
        }

        protected List<Object> List()
        {
            return _List;
        }

        public TPrayer_Item Get_Item(int Index)
        {
            return (TPrayer_Item)_List[Index];
        }

        public void Set_Item(int Index, TPrayer_Item Value)
        {
            _List[Index] = Value;
        }

        public string URL;
        public string Password; /* Reserved for client to save */

        public override int Count()
        {
            return _List.Count();
        }

        public int Add(TPrayer_Item Value)
        {
            _List.Add(Value);
            Value.Parent = this;
            return _List.Count() - 1;
        }
        public void Delete(int Value)
        {
            _List.RemoveAt(Value);
        }

        /* Should pass False if not storing data securely */
        public string Serialize(bool Include_Password = true)
        {
            string Result = "<url>" + URL + "</url>";
            if (Include_Password)
            {
                Result = Result + "<pass>" + Password + "</pass>";
            }
            for (int I = 0; I < _List.Count(); I++)
            {
                TPrayer_Item Item = Get_Item(I);
                Result = Result + "<item>" + Item.Serialize() + "</item>";
            }
            return Result;
        }
    } // TPrayer_List

    class TDirectory_Entry
    {
        public string Name;
        public string URL;
        public int Tag; /* For developer use */

        public TDirectory_Entry()
        {
            Name = "";
            URL = "";
            Tag = 0;
        }
    }

    class TDirectory : TEPPJ_File
    {
        private List<Object> _List = new List<Object>();

        public TDirectory()
        {
            File_Type = TFileType.FT_Directory;
        }

        protected List<Object> List()
        {
            return _List;
        }

        public int Add(TDirectory_Entry Value)
        {
            _List.Add(Value);
            return _List.Count() - 1;
        }

        public override int Count()
        {
            return _List.Count();
        }

        public string Name(int Index)
        {
            return ((TDirectory_Entry)_List[Index]).Name;
        }

        public string URL(int Index)
        {
            return ((TDirectory_Entry)_List[Index]).URL;
        }
        public TDirectory_Entry Entry(int Index)
        {
            return ((TDirectory_Entry)_List[Index]);
        }

        public int Indexof_Name(string S)
        {
            for (int I = 0; I < Count(); I--)
            {
                if (Entry(I).Name == S)
                {
                    return I;
                }
            }
            return -1;
        }
    }

    public class TURL_Source
    {
        public virtual string Get_Text(string URL)
        {
            return "";
        }
    }

    public class TLoad_Balance
    {
        public int Percent;
        public string URL;
        public TLoad_Balance()
        {
            Percent = 0;
            URL = "";
        }

    }

    public class TLoad_Balance_List
    {
        private List<Object> _List = new List<object>();

        protected List<Object> List()
        {
            return _List;
        }

        public void Append(string Spec)
        {
            TLoad_Balance Balance = new TLoad_Balance();
            Balance.URL = Spec;
            _List.Add(Balance);
        }

        public void Prepend(int P, string Spec)
        {
            TLoad_Balance Balance = new TLoad_Balance();
            Balance.URL = Spec;
            Balance.Percent = P;
            _List.Insert(0, Balance);
        }

        string Get_URL(TURL_Source Source, string U)
        {
            if (Source != null)
            {
                return Source.Get_Text(U);
            }
            return "";
        }

        public string Pick_URL(TURL_Source Source)
        {
            string Result = "";

            /* Determine metrics... */
            int Count = 0;
            int Total = 0;
            for (int Index = 0; Index < _List.Count(); Index++)
            {
                Total = Total + ((TLoad_Balance)_List[Index]).Percent;
                if (((TLoad_Balance)_List[Index]).Percent == 0)
                {
                    Count++;
                }
            }

            /* For specs without a percentage, spread any remaning percentage among them...*/
            if (Count > 0) /* Have unspecified specs */
            {
                Total = (100 - Total) / Count; /* Remaining percentage to split between specs */
                if (Total < 1) Total = 1; /* No less than 1% to each spec*/
                for (int Index = 0; Index < _List.Count(); Index++)
                {
                    if (((TLoad_Balance)_List[Index]).Percent == 0)
                    {
                        ((TLoad_Balance)_List[Index]).Percent = Total;
                    }
                }
            }

            /* Now pick one at random... */
            Random rnd = new Random();
            while (true) /* Loop until we find a valid url */
            {
                int P = rnd.Next(100); /* Determine percentage */
                for (int Index = 0; Index < _List.Count(); Index++)
                {
                    if (
                        (((TLoad_Balance)_List[Index]).Percent <= P)
                        ||
                        (Index == _List.Count() - 1)
                      )
                    {
                        /* Found a match, or ran out of possible targets... */
                        Result = Get_URL(Source, ((TLoad_Balance)_List[Index]).URL);
                        if (Result.IndexOf("<eppj>", 0) != -1) return Result; /* Exit with our find */
                        Result = ""; /* Otherwise, the target is not valid */
                        _List.RemoveAt(Index); /* Remove URL from choices */
                        break; /* Try another random choice */
                    }
                    else
                    {
                        P = P - ((TLoad_Balance)_List[Index]).Percent; /* Adjust for next check*/
                    }
                }
            }
        } // Pick_URL
    } // Load_Balance_List

    public class TEPPJ
    {
        string Get_URL(TURL_Source Source, string U)
        {
            if (Source != null)
            {
                return Source.Get_Text(U);
            }
            return "";
        }

        string Get_Tag_Contents(string Name, ref string S)
        /* Get text up to specified tag */
        {
            int I = S.IndexOf("<" + Name + ">", 0);
            if (I == -1) I = S.Length + 1;
            string Result = "";
            if (I > 0) // Tag doesn't start string
            {
                Result = S.Substring(0, I);
            }
            if (I + Name.Length + 1 >= S.Length)
            {
                S = "";
            }
            else
            {
                S = S.Substring(I + Name.Length + 1);
            }
            return Result;
        }

        string Next_Tag(ref string S)
        {
            string Result = "";
            int I = S.IndexOf("<", 0);
            if (I == -1) return ""; /* No more tags */
            int E = S.IndexOf(">", I);
            if (E == -1) E = S.Length + 1;
            Result = S.Substring(I, E - I + 1);
            Result.ToLower();
            if (E >= S.Length)
            {
                S = "";
            }
            else
            {
                S = S.Substring(E + 1);
            }
            return Result;
        }

        public TLoad_Balance_List Parse_Load_Balance(string S)
        {
            TLoad_Balance_List Result = new TLoad_Balance_List();
            while (S != "")
            {
                string Spec = Get_Tag_Contents("</balance>", ref S);
                int I = Spec.IndexOf("%::", 0);
                if (I == -1)
                {
                    Result.Append(Spec);
                }
                else
                {
                    string S1 = Spec.Substring(0, I - 2);
                    if (Int32.TryParse(S1, out I))
                    {
                        Result.Prepend(I, Spec);
                    }

                    S = Get_Tag_Contents("<balance>", ref S); /* Find next balance tag */
                }
            }
            return Result;
        }

        public TEPPJ_File Parse_File(string S, TURL_Source Source, bool Redirection, bool Load_Balance)
        {
            if (S == "") return null; /* Probably a failure to load file... */
            if( (S.Length > 5) && (S.Substring(0, 6) == "secure") )
            {
                return new TSecurity();
            }
            if( S.IndexOf("<eppj>", 0) == -1 ) return null; /* Not an eppj file... */
            TDirectory Dir = null;
            TPrayer_Item Item = null;

            Get_Tag_Contents("eppj", ref S); /* Read (ignore) up to, and including, <eppj> */
            TEPPJ_File Result = null;

            string Tag = Next_Tag(ref S);
            while (Tag != "")
            {
                if (Tag == "<redirect>")
                {
                    Tag = Get_Tag_Contents("/redirect", ref S);
                    if (!Redirection)
                    {
                        Load_EPPJ(Tag, Source, true, Load_Balance);
                        return Result;
                    }
                }
                else
                if (Tag == "<balance>")
                {
                    if (!Load_Balance)
                    {
                        Load_Balance = true;
                        TLoad_Balance_List LBL = Parse_Load_Balance(S);
                        S = LBL.Pick_URL(Source);
                        LBL = null;
                        if (S == "")
                        {
                            return Result; /* No valid balance target found */
                        }
                    }
                }
                else
                if (Tag == "<dir>")
                {
                    if (Result == null)
                    {
                        Dir = new TDirectory();
                        Result = Dir;
                    }
                    if (Result.File_Type == TFileType.FT_Directory)
                    {
                        string SS = Get_Tag_Contents("/dir", ref S);
                        TDirectory_Entry Entry = new TDirectory_Entry();
                        Dir.Add(Entry);
                        while (SS != "")
                        {
                            Tag = Next_Tag(ref SS);
                            if (Tag == "<name>")
                            {
                                Entry.Name = Get_Tag_Contents("/name", ref SS);
                            }
                            else
                            if (Tag == "<url>")
                            {
                                Entry.URL = Get_Tag_Contents("/url", ref SS);
                            }
                            else
                            {
                                /* Unrecognized tag - ignore it... */
                                Get_Tag_Contents("/" + Tag.Substring(1, Tag.Length), ref SS);
                            }
                        }
                    }
                }
                else
                if (Tag == "<item>")
                {
                    if (Result == null)
                    {
                        Result = new TPrayer_List();
                    }
                    if (Result.File_Type == TFileType.FT_List)
                    {
                        if (Item == null)
                        {
                            Item = new TPrayer_Item();
                            ((TPrayer_List)Result).Add(Item);
                        }
                    }
                }
                else
                if (Tag == "</item>")
                {
                    Item = null;
                }
                else
                if (Tag == "<id>")
                {
                    if (Item != null)
                    {
                        Item.ID = Get_Tag_Contents("/id", ref S);
                    }
                }
                else
                if (Tag == "<title>")
                {
                    if (Item != null)
                    {
                        Item.Title = Get_Tag_Contents("/title", ref S);
                    }
                }
                else
                if (Tag == "<text>")
                {
                    if (Item != null)
                    {
                        Item.Text = Get_Tag_Contents("/text", ref S);
                    }
                }
                else
                if (Tag == "<more>")
                {
                    if (Item != null)
                    {
                        Item.More = Get_Tag_Contents("/more", ref S);
                    }
                }
                else
                if (Tag == "<image>")
                {
                    if (Item != null)
                    {
                        Item.Image = Get_Tag_Contents("/image", ref S);
                    }
                }
                else
                if (Tag == "<answered>")
                {
                    if (Item != null)
                    {
                        Item.Answered = Get_Tag_Contents("/answered", ref S);
                    }
                }
                else
                if (Tag == "<set>")
                {
                    if (Item != null)
                    {
                        Item._Set = Get_Tag_Contents("/set", ref S);
                    }
                    ;
                }
                else
                if (Tag == "<pass>")
                {
                    if (Result == null)
                    {
                        Result = new TPrayer_List();
                    }
                    if (Result.File_Type == TFileType.FT_List)
                    {
                        ((TPrayer_List)Result).Password = Get_Tag_Contents("/pass", ref S);
                    }
                }
                else
                if (Tag == "<url>")
                {
                    if (Result == null)
                    {
                        Result = new TPrayer_List();
                    }
                    if (Result.File_Type == TFileType.FT_List)
                    {
                        ((TPrayer_List)Result).URL = Get_Tag_Contents("/url", ref S);
                    }
                }
                else
                if (Tag == "<startdate>")
                {
                    if (Item != null)
                    {
                        Item.Startdate = Get_Tag_Contents("/startdate", ref S);
                    }
                }
                else
                if (Tag == "<enddate>")
                {
                    if (Item != null)
                    {
                        Item.enddate = Get_Tag_Contents("/enddate", ref S);
                    }
                }
                else
                if (Tag == "<hidden>")
                {
                    if (Item != null)
                    {
                        Item.Hidden = true;
                    }
                }
                else
                if (Tag == "<urgent>")
                {
                    if (Item != null)
                    {
                        Item.Urgent = Get_Tag_Contents("/urgent", ref S);
                    }
                }
                else
                {
                    /* Unrecognized tag - ignore it... */
                    Get_Tag_Contents("/" + Tag.Substring(1, Tag.Length), ref S);
                }
                Tag = Next_Tag(ref S);
            }
            return Result;
        } /* Parse_File */


        public TEPPJ_File Load_EPPJ(string URL, TURL_Source Source,
            bool Redirection, bool Load_Balance)
        {
            string S = Get_URL(Source, URL);
            return Parse_File(S, Source, Redirection, Load_Balance);
        }
    } // class EPPJ
}; // namespace _EPPJ