/* ====================================================================
   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 AL.Utils.NPOI.HSSF.Record.Aggregates
{

    using System;
    using System.Text;
    using System.Collections.Generic;
    using AL.Utils.NPOI.HSSF.Model;
    using AL.Utils.NPOI.HSSF.Record;

    using AL.Utils.NPOI.SS.Util;
    /**
     * 
     * @author Josh Micich
     */
    public class MergedCellsTable : RecordAggregate
    {
        private const int MAX_MERGED_REGIONS = 1027; // enforced by the 8224 byte limit

        private List<CellRangeAddress> _mergedRegions;

        /// <summary>
        /// Creates an empty aggregate
        /// </summary>
        public MergedCellsTable()
        {
            _mergedRegions = new List<CellRangeAddress>();
        }
       
        /**
         * Reads zero or more consecutive {@link MergeCellsRecord}s
         * @param rs
         */
        public void Read(RecordStream rs)
        {
            
            while (rs.PeekNextClass() == typeof(MergeCellsRecord))
            {
                MergeCellsRecord mcr = (MergeCellsRecord)rs.GetNext();
                int nRegions = mcr.NumAreas;
                for (int i = 0; i < nRegions; i++)
                {
                    _mergedRegions.Add(mcr.GetAreaAt(i));
                }
            }
        }

        public override int RecordSize
        {
            get
            {
                // a bit cheaper than the default impl
                int nRegions = _mergedRegions.Count;
                if (nRegions < 1)
                {
                    // no need to write a single empty MergeCellsRecord
                    return 0;
                }
                int nMergedCellsRecords = nRegions / MAX_MERGED_REGIONS;
                int nLeftoverMergedRegions = nRegions % MAX_MERGED_REGIONS;

                int result = nMergedCellsRecords
                        * (4 + CellRangeAddressList.GetEncodedSize(MAX_MERGED_REGIONS)) + 4
                        + CellRangeAddressList.GetEncodedSize(nLeftoverMergedRegions);
                return result;
            }
        }

        public override void VisitContainedRecords(RecordVisitor rv)
        {
            int nRegions = _mergedRegions.Count;
            if (nRegions < 1)
            {
                // no need to write a single empty MergeCellsRecord
                return;
            }

            int nFullMergedCellsRecords = nRegions / MAX_MERGED_REGIONS;
            int nLeftoverMergedRegions = nRegions % MAX_MERGED_REGIONS;

            CellRangeAddress[] cras = (CellRangeAddress[])_mergedRegions.ToArray();

            for (int i = 0; i < nFullMergedCellsRecords; i++)
            {
                int startIx = i * MAX_MERGED_REGIONS;
                rv.VisitRecord(new MergeCellsRecord(cras, startIx, MAX_MERGED_REGIONS));
            }
            if (nLeftoverMergedRegions > 0)
            {
                int startIx = nFullMergedCellsRecords * MAX_MERGED_REGIONS;
                rv.VisitRecord(new MergeCellsRecord(cras, startIx, nLeftoverMergedRegions));
            }
        }
        public void AddRecords(MergeCellsRecord[] mcrs)
        {
            for (int i = 0; i < mcrs.Length; i++)
            {
                AddMergeCellsRecord(mcrs[i]);
            }
        }

        private void AddMergeCellsRecord(MergeCellsRecord mcr)
        {
            int nRegions = mcr.NumAreas;
            for (int i = 0; i < nRegions; i++)
            {
                _mergedRegions.Add(mcr.GetAreaAt(i));
            }
        }


        public List<CellRangeAddress> MergedRegions
        {
            get
            {
                return _mergedRegions;
            }
        }

        public CellRangeAddress Get(int index)
        {
            CheckIndex(index);
            return (CellRangeAddress)_mergedRegions[index];
        }

        public void Remove(int index)
        {
            CheckIndex(index);
            _mergedRegions.RemoveAt(index);
        }

        private void CheckIndex(int index)
        {
            if (index < 0 || index >= _mergedRegions.Count)
            {
                throw new ArgumentException("Specified CF index " + index
                        + " is outside the allowable range (0.." + (_mergedRegions.Count - 1) + ")");
            }
        }

        public void AddArea(int rowFrom, int colFrom, int rowTo, int colTo)
        {
            _mergedRegions.Add(new CellRangeAddress(rowFrom, rowTo, colFrom, colTo));
        }

        public int NumberOfMergedRegions
        {
            get
            {
                return _mergedRegions.Count;
            }
        }
    }
}
