/* ====================================================================
   Licensed to the Apache Software Foundation (ASF) Under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for Additional information regarding copyright ownership.
   The ASF licenses this file to You Under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed Under the License is distributed on an "AS Is" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations Under the License.
==================================================================== */

namespace HH.WMS.Utils.NPOI.HSSF.Model
{
    using System;
    using System.Text;
    using System.Collections;
    using System.Collections.Generic;

    using HH.WMS.Utils.NPOI.HSSF.Record;
    using HH.WMS.Utils.NPOI.SS.Formula;
    using HH.WMS.Utils.NPOI.SS.Formula.PTG;

    /**
     * Link Table (OOO pdf reference: 4.10.3 ) <p/>
     *
     * The main data of all types of references is stored in the Link Table inside the Workbook Globals
     * Substream (4.2.5). The Link Table itself is optional and occurs only, if  there are any
     * references in the document.
     *  <p/>
     *
     *  In BIFF8 the Link Table consists of
     *  <ul>
     *  <li>zero or more EXTERNALBOOK Blocks<p/>
     *  	each consisting of
     *  	<ul>
     *  	<li>exactly one EXTERNALBOOK (0x01AE) record</li>
     *  	<li>zero or more EXTERNALNAME (0x0023) records</li>
     *  	<li>zero or more CRN Blocks<p/>
     *			each consisting of
     *  		<ul>
     *  		<li>exactly one XCT (0x0059)record</li>
     *  		<li>zero or more CRN (0x005A) records (documentation says one or more)</li>
     *  		</ul>
     *  	</li>
     *  	</ul>
     *  </li>
     *  <li>zero or one EXTERNSHEET (0x0017) record</li>
     *  <li>zero or more DEFINEDNAME (0x0018) records</li>
     *  </ul>
     *
     *
     * @author Josh Micich
     */
    public class LinkTable
    {
        // TODO make this class into a record aggregate

        private static ExternSheetRecord ReadExtSheetRecord(RecordStream rs)
        {
            List<ExternSheetRecord> temp = new List<ExternSheetRecord>(2);
            while (rs.PeekNextClass() == typeof(ExternSheetRecord))
            {
                temp.Add((ExternSheetRecord)rs.GetNext());
            }

            int nItems = temp.Count;
            if (nItems < 1)
            {
                throw new Exception("Expected an EXTERNSHEET record but got ("
                        + rs.PeekNextClass().Name + ")");
            }
            if (nItems == 1)
            {
                // this is the normal case. There should be just one ExternSheetRecord
                return temp[0];
            }
            // Some apps generate multiple ExternSheetRecords (see bug 45698).
            // It seems like the best thing to do might be to combine these into one
            ExternSheetRecord[] esrs = new ExternSheetRecord[nItems];
            esrs = temp.ToArray();
            return ExternSheetRecord.Combine(esrs);
        }

        private class CRNBlock
        {

            private CRNCountRecord _countRecord;
            private CRNRecord[] _crns;

            public CRNBlock(RecordStream rs)
            {
                _countRecord = (CRNCountRecord)rs.GetNext();
                int nCRNs = _countRecord.NumberOfCRNs;
                CRNRecord[] crns = new CRNRecord[nCRNs];
                for (int i = 0; i < crns.Length; i++)
                {
                    crns[i] = (CRNRecord)rs.GetNext();
                }
                _crns = crns;
            }
            public CRNRecord[] GetCrns()
            {
                return (CRNRecord[])_crns.Clone();
            }
        }

        private class ExternalBookBlock
        {
            private SupBookRecord _externalBookRecord;
            private ExternalNameRecord[] _externalNameRecords;
            private CRNBlock[] _crnBlocks;
            /**
         * Create a new block for registering add-in functions
         *
         * @see org.apache.poi.hssf.model.LinkTable#addNameXPtg(String)
         */
            public ExternalBookBlock()
            {
                _externalBookRecord = SupBookRecord.CreateAddInFunctions();
                _externalNameRecords = new ExternalNameRecord[0];
                _crnBlocks = new CRNBlock[0];
            }
            public ExternalBookBlock(RecordStream rs)
            {
                _externalBookRecord = (SupBookRecord)rs.GetNext();
                ArrayList temp = new ArrayList();
                while (rs.PeekNextClass() == typeof(ExternalNameRecord))
                {
                    temp.Add(rs.GetNext());
                }
                _externalNameRecords = (ExternalNameRecord[])temp.ToArray(typeof(ExternalNameRecord));

                temp.Clear();

                while (rs.PeekNextClass() == typeof(CRNCountRecord))
                {
                    temp.Add(new CRNBlock(rs));
                }
                _crnBlocks = (CRNBlock[])temp.ToArray(typeof(CRNBlock));
            }
            public int NumberOfNames
            {
                get
                {
                    return _externalNameRecords.Length;
                }
            }
            public int AddExternalName(ExternalNameRecord rec)
            {
                ExternalNameRecord[] tmp = new ExternalNameRecord[_externalNameRecords.Length + 1];
                Array.Copy(_externalNameRecords, 0, tmp, 0, _externalNameRecords.Length);
                tmp[tmp.Length - 1] = rec;
                _externalNameRecords = tmp;
                return _externalNameRecords.Length - 1;
            }
            /**
         * Create a new block for internal references. It is called when constructing a new LinkTable.
         *
         * @see org.apache.poi.hssf.model.LinkTable#LinkTable(int, WorkbookRecordList)
         */
            public ExternalBookBlock(int numberOfSheets)
            {
                _externalBookRecord = SupBookRecord.CreateInternalReferences((short)numberOfSheets);
                _externalNameRecords = new ExternalNameRecord[0];
                _crnBlocks = new CRNBlock[0];
            }

            public SupBookRecord GetExternalBookRecord()
            {
                return _externalBookRecord;
            }

            public String GetNameText(int definedNameIndex)
            {
                return _externalNameRecords[definedNameIndex].Text;
            }
            /**
 * Performs case-insensitive search
 * @return -1 if not found
 */
            public int GetIndexOfName(String name)
            {
                for (int i = 0; i < _externalNameRecords.Length; i++)
                {
                    if (_externalNameRecords[i].Text.Equals(name, StringComparison.OrdinalIgnoreCase))
                    {
                        return i;
                    }
                }
                return -1;
            }

            public int GetNameIx(int definedNameIndex)
            {
                return _externalNameRecords[definedNameIndex].Ix;
            }

        }

        private ExternalBookBlock[] _externalBookBlocks;
        private ExternSheetRecord _externSheetRecord;
        private List<NameRecord> _definedNames;
        private int _recordCount;
        private WorkbookRecordList _workbookRecordList; // TODO - would be nice to Remove this

        public LinkTable(List<Record> inputList, int startIndex, WorkbookRecordList workbookRecordList, Dictionary<String, NameCommentRecord> commentRecords)
        {

            _workbookRecordList = workbookRecordList;
            RecordStream rs = new RecordStream(inputList, startIndex);

            ArrayList temp = new ArrayList();
            while (rs.PeekNextClass() == typeof(SupBookRecord))
            {
                temp.Add(new ExternalBookBlock(rs));
            }

            //_externalBookBlocks = new ExternalBookBlock[temp.Count];
            _externalBookBlocks = (ExternalBookBlock[])temp.ToArray(typeof(ExternalBookBlock));
            temp.Clear();

            if (_externalBookBlocks.Length > 0)
            {
                // If any ExternalBookBlock present, there is always 1 of ExternSheetRecord
                if (rs.PeekNextClass() != typeof(ExternSheetRecord))
                {
                    // not quite - if written by google docs
                    _externSheetRecord = null;
                }
                else
                {
                    _externSheetRecord = ReadExtSheetRecord(rs);
                }
            }
            else
            {
                _externSheetRecord = null;
            }

            _definedNames = new List<NameRecord>();
            // collect zero or more DEFINEDNAMEs id=0x18
            while (true)
            {

                Type nextClass = rs.PeekNextClass();
                if (nextClass == typeof(NameRecord))
                {
                    NameRecord nr = (NameRecord)rs.GetNext();
                    _definedNames.Add(nr);
                }
                else if (nextClass == typeof(NameCommentRecord))
                {
                    NameCommentRecord ncr = (NameCommentRecord)rs.GetNext();
                    commentRecords.Add(ncr.NameText, ncr);
                }
                else
                {
                    break;
                }
            }

            _recordCount = rs.GetCountRead();
            for (int i = startIndex; i < startIndex + _recordCount; i++)
            {
                _workbookRecordList.Records.Add(inputList[i]);
            }

        }

        public LinkTable(int numberOfSheets, WorkbookRecordList workbookRecordList)
        {
            _workbookRecordList = workbookRecordList;
            _definedNames = new List<NameRecord>();
            _externalBookBlocks = new ExternalBookBlock[] {
				new ExternalBookBlock(numberOfSheets),
		    };
            _externSheetRecord = new ExternSheetRecord();
            _recordCount = 2;

            // tell _workbookRecordList about the 2 new records

            SupBookRecord supbook = _externalBookBlocks[0].GetExternalBookRecord();

            int idx = FindFirstRecordLocBySid(CountryRecord.sid);
            if (idx < 0)
            {
                throw new Exception("CountryRecord not found");
            }
            _workbookRecordList.Add(idx + 1, _externSheetRecord);
            _workbookRecordList.Add(idx + 1, supbook);
        }

        /**
         * TODO - would not be required if calling code used RecordStream or similar
         */
        public int RecordCount
        {
            get { return _recordCount; }
        }


        public NameRecord GetSpecificBuiltinRecord(byte builtInCode, int sheetNumber)
        {

            IEnumerator iterator = _definedNames.GetEnumerator();
            while (iterator.MoveNext())
            {
                NameRecord record = (NameRecord)iterator.Current;

                //print areas are one based
                if (record.BuiltInName == builtInCode && record.SheetNumber == sheetNumber)
                {
                    return record;
                }
            }

            return null;
        }

        public void RemoveBuiltinRecord(byte name, int sheetIndex)
        {
            //the name array is smaller so searching through it should be faster than
            //using the FindFirstXXXX methods
            NameRecord record = GetSpecificBuiltinRecord(name, sheetIndex);
            if (record != null)
            {
                _definedNames.Remove(record);
            }
            // TODO - do we need "Workbook.records.Remove(...);" similar to that in Workbook.RemoveName(int namenum) {}?
        }
        /**
 * @param extRefIndex as from a {@link Ref3DPtg} or {@link Area3DPtg}
 * @return -1 if the reference is to an external book
 */
        public int GetIndexToInternalSheet(int extRefIndex)
        {
            return _externSheetRecord.GetFirstSheetIndexFromRefIndex(extRefIndex);
        }
        public int NumNames
        {
            get
            {
                return _definedNames.Count;
            }
        }
        private int FindRefIndexFromExtBookIndex(int extBookIndex)
        {
            return _externSheetRecord.FindRefIndexFromExtBookIndex(extBookIndex);
        }
        public NameXPtg GetNameXPtg(String name)
        {
            // first find any external book block that contains the name:
            for (int i = 0; i < _externalBookBlocks.Length; i++)
            {
                int definedNameIndex = _externalBookBlocks[i].GetIndexOfName(name);
                if (definedNameIndex < 0)
                {
                    continue;
                }
                // found it.
                int sheetRefIndex = FindRefIndexFromExtBookIndex(i);
                if (sheetRefIndex >= 0)
                {
                    return new NameXPtg(sheetRefIndex, definedNameIndex);
                }
            }
            return null;
        }
        public NameRecord GetNameRecord(int index)
        {
            return (NameRecord)_definedNames[index];
        }

        public void AddName(NameRecord name)
        {
            _definedNames.Add(name);

            // TODO - this Is messy
            // Not the most efficient way but the other way was causing too many bugs
            int idx = FindFirstRecordLocBySid(ExternSheetRecord.sid);
            if (idx == -1) idx = FindFirstRecordLocBySid(SupBookRecord.sid);
            if (idx == -1) idx = FindFirstRecordLocBySid(CountryRecord.sid);
            int countNames = _definedNames.Count;
            _workbookRecordList.Add(idx + countNames, name);

        }
        /**
     * Register an external name in this workbook
     *
     * @param name  the name to register
     * @return a NameXPtg describing this name 
     */
        public NameXPtg AddNameXPtg(String name)
        {
            int extBlockIndex = -1;
            ExternalBookBlock extBlock = null;

            // find ExternalBlock for Add-In functions and remember its index
            for (int i = 0; i < _externalBookBlocks.Length; i++)
            {
                SupBookRecord ebr = _externalBookBlocks[i].GetExternalBookRecord();
                if (ebr.IsAddInFunctions)
                {
                    extBlock = _externalBookBlocks[i];
                    extBlockIndex = i;
                    break;
                }
            }
            // An ExternalBlock for Add-In functions was not found. Create a new one.
            if (extBlock == null)
            {
                extBlock = new ExternalBookBlock();

                ExternalBookBlock[] tmp = new ExternalBookBlock[_externalBookBlocks.Length + 1];
                Array.Copy(_externalBookBlocks, 0, tmp, 0, _externalBookBlocks.Length);
                tmp[tmp.Length - 1] = extBlock;
                _externalBookBlocks = tmp;

                extBlockIndex = _externalBookBlocks.Length - 1;

                // add the created SupBookRecord before ExternSheetRecord
                int idx = FindFirstRecordLocBySid(ExternSheetRecord.sid);
                _workbookRecordList.Add(idx, extBlock.GetExternalBookRecord());

                // register the SupBookRecord in the ExternSheetRecord
                // -2 means that the scope of this name is Workbook and the reference applies to the entire workbook.
                _externSheetRecord.AddRef(_externalBookBlocks.Length - 1, -2, -2);
            }

            // create a ExternalNameRecord that will describe this name
            ExternalNameRecord extNameRecord = new ExternalNameRecord();
            extNameRecord.Text = (name);
            // The docs don't explain why Excel set the formula to #REF!
            extNameRecord.SetParsedExpression(new Ptg[] { ErrPtg.REF_INVALID });

            int nameIndex = extBlock.AddExternalName(extNameRecord);
            int supLinkIndex = 0;
            // find the posistion of the Add-In SupBookRecord in the workbook stream,
            // the created ExternalNameRecord will be appended to it
            for (IEnumerator iterator = _workbookRecordList.GetEnumerator(); iterator.MoveNext(); supLinkIndex++)
            {
                Record record = (Record)iterator.Current;
                if (record is SupBookRecord)
                {
                    if (((SupBookRecord)record).IsAddInFunctions) break;
                }
            }
            int numberOfNames = extBlock.NumberOfNames;
            // a new name is inserted in the end of the SupBookRecord, after the last name
            _workbookRecordList.Add(supLinkIndex + numberOfNames, extNameRecord);
            int ix = _externSheetRecord.GetRefIxForSheet(extBlockIndex, -2 /* the scope is workbook*/);
            return new NameXPtg(ix, nameIndex);
        }
        public void RemoveName(int namenum)
        {
            _definedNames.RemoveAt(namenum);
        }

        public int GetSheetIndexFromExternSheetIndex(int extRefIndex)
        {
            if (extRefIndex >= _externSheetRecord.NumOfRefs)
            {
                return -1;
            }
            return _externSheetRecord.GetFirstSheetIndexFromRefIndex(extRefIndex);
        }
        private static int GetSheetIndex(String[] sheetNames, String sheetName)
        {
            for (int i = 0; i < sheetNames.Length; i++)
            {
                if (sheetNames[i].Equals(sheetName))
                {
                    return i;
                }

            }
            throw new InvalidOperationException("External workbook does not contain sheet '" + sheetName + "'");
        }
        public int GetExternalSheetIndex(String workbookName, String sheetName)
        {
            SupBookRecord ebrTarget = null;
            int externalBookIndex = -1;
            for (int i = 0; i < _externalBookBlocks.Length; i++)
            {
                SupBookRecord ebr = _externalBookBlocks[i].GetExternalBookRecord();
                if (!ebr.IsExternalReferences)
                {
                    continue;
                }
                if (workbookName.Equals(ebr.URL))
                { // not sure if 'equals()' works when url has a directory
                    ebrTarget = ebr;
                    externalBookIndex = i;
                    break;
                }
            }
            if (ebrTarget == null)
            {
                throw new NullReferenceException("No external workbook with name '" + workbookName + "'");
            }
            int sheetIndex = GetSheetIndex(ebrTarget.SheetNames, sheetName);

            int result = _externSheetRecord.GetRefIxForSheet(externalBookIndex, sheetIndex);
            if (result < 0)
            {
                throw new InvalidOperationException("ExternSheetRecord does not contain combination ("
                        + externalBookIndex + ", " + sheetIndex + ")");
            }
            return result;
        }
        public String[] GetExternalBookAndSheetName(int extRefIndex)
        {
            int ebIx = _externSheetRecord.GetExtbookIndexFromRefIndex(extRefIndex);
            SupBookRecord ebr = _externalBookBlocks[ebIx].GetExternalBookRecord();
            if (!ebr.IsExternalReferences)
            {
                return null;
            }
            int shIx = _externSheetRecord.GetFirstSheetIndexFromRefIndex(extRefIndex);
            String usSheetName = null;
            if (shIx >= 0)
            {
                usSheetName = (String)ebr.SheetNames.GetValue(shIx);
            }
            return new String[] {
				ebr.URL,
				usSheetName,
		    };
        }
        public int CheckExternSheet(int sheetIndex)
        {
            int thisWbIndex = -1; // this is probably always zero
            for (int i = 0; i < _externalBookBlocks.Length; i++)
            {
                SupBookRecord ebr = _externalBookBlocks[i].GetExternalBookRecord();
                if (ebr.IsInternalReferences)
                {
                    thisWbIndex = i;
                    break;
                }
            }
            if (thisWbIndex < 0)
            {
                throw new InvalidOperationException("Could not find 'internal references' EXTERNALBOOK");
            }

            //Trying to find reference to this sheet
            int j = _externSheetRecord.GetRefIxForSheet(thisWbIndex, sheetIndex);
            if (j >= 0)
            {
                return j;
            }
            //We haven't found reference to this sheet
            return _externSheetRecord.AddRef(thisWbIndex, sheetIndex, sheetIndex);

        }


        /**
         * copied from Workbook
         */
        private int FindFirstRecordLocBySid(short sid)
        {
            int index = 0;
            for (IEnumerator iterator = _workbookRecordList.GetEnumerator(); iterator.MoveNext(); )
            {
                Record record = (Record)iterator.Current;

                if (record.Sid == sid)
                {
                    return index;
                }
                index++;
            }
            return -1;
        }

        public String ResolveNameXText(int refIndex, int definedNameIndex)
        {
            int extBookIndex = _externSheetRecord.GetExtbookIndexFromRefIndex(refIndex);
            return _externalBookBlocks[extBookIndex].GetNameText(definedNameIndex);
        }
        public int ResolveNameXIx(int refIndex, int definedNameIndex)
        {
            int extBookIndex = _externSheetRecord.GetExtbookIndexFromRefIndex(refIndex);
            return _externalBookBlocks[extBookIndex].GetNameIx(definedNameIndex);
        }
    }
}