using System;
using System.Collections.Generic;
using System.Linq;

namespace ClosedXML.Excel
{
    internal class XLNamedRanges : IXLNamedRanges
    {
        private readonly Dictionary<String, IXLNamedRange> _namedRanges = new Dictionary<String, IXLNamedRange>();
        internal XLWorkbook Workbook { get; set; }
        internal XLWorksheet Worksheet { get; set; }

        public XLNamedRanges(XLWorksheet worksheet)
            : this(worksheet.Workbook)
        {
            Worksheet = worksheet;
        }

        public XLNamedRanges(XLWorkbook workbook)
        {
            Workbook = workbook;
        }

        #region IXLNamedRanges Members

        public IXLNamedRange NamedRange(String rangeName)
        {
            IXLNamedRange range;
            if (_namedRanges.TryGetValue(rangeName, out range))
                return range;

            return null;
        }

        public IXLNamedRange Add(String rangeName, String rangeAddress)
        {
            return Add(rangeName, rangeAddress, null);
        }

        public IXLNamedRange Add(String rangeName, IXLRange range)
        {
            return Add(rangeName, range, null);
        }

        public IXLNamedRange Add(String rangeName, IXLRanges ranges)
        {
            return Add(rangeName, ranges, null);
        }

        public IXLNamedRange Add(String rangeName, String rangeAddress, String comment)
        {
            return Add(rangeName, rangeAddress, comment, false);
        }

        /// <summary>
        /// Adds the specified range name.
        /// </summary>
        /// <param name="rangeName">Name of the range.</param>
        /// <param name="rangeAddress">The range address.</param>
        /// <param name="comment">The comment.</param>
        /// <param name="acceptInvalidReferences">if set to <c>true</c> range address will not be checked for validity. Necessary when loading files as is.</param>
        /// <returns></returns>
        /// <exception cref="System.ArgumentException">For named ranges in the workbook scope, specify the sheet name in the reference.</exception>
        internal IXLNamedRange Add(String rangeName, String rangeAddress, String comment, bool acceptInvalidReferences)
        {
            if (!acceptInvalidReferences)
            {
                var match = XLHelper.NamedRangeReferenceRegex.Match(rangeAddress);

                if (!match.Success)
                {
                    var range = Worksheet?.Range(rangeAddress) ?? Workbook.Range(rangeAddress);
                    if (range == null)
                        throw new ArgumentException(string.Format("The range address '{0}' for the named range '{1}' is not a valid range.", rangeAddress, rangeName));
                    else
                    {
                        if (Worksheet == null || !XLHelper.NamedRangeReferenceRegex.Match(range.ToString()).Success)
                            throw new ArgumentException("For named ranges in the workbook scope, specify the sheet name in the reference.");
                        else
                            rangeAddress = Worksheet.Range(rangeAddress).ToString();
                    }
                }
            }

            var namedRange = new XLNamedRange(this, rangeName, rangeAddress, comment);
            _namedRanges.Add(rangeName, namedRange);
            return namedRange;
        }

        public IXLNamedRange Add(String rangeName, IXLRange range, String comment)
        {
            var ranges = new XLRanges { range };
            return Add(rangeName, ranges, comment);
        }

        public IXLNamedRange Add(String rangeName, IXLRanges ranges, String comment)
        {
            var namedRange = new XLNamedRange(this, rangeName, ranges, comment);
            _namedRanges.Add(rangeName, namedRange);
            return namedRange;
        }

        public void Delete(String rangeName)
        {
            _namedRanges.Remove(rangeName);
        }

        public void Delete(Int32 rangeIndex)
        {
            _namedRanges.Remove(_namedRanges.ElementAt(rangeIndex).Key);
        }

        public void DeleteAll()
        {
            _namedRanges.Clear();
        }

        #endregion IXLNamedRanges Members

        #region IEnumerable<IXLNamedRange> Members

        public IEnumerator<IXLNamedRange> GetEnumerator()
        {
            return _namedRanges.Values.GetEnumerator();
        }

        #endregion IEnumerable<IXLNamedRange> Members

        #region IEnumerable Members

        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
        {
            return GetEnumerator();
        }

        #endregion IEnumerable Members

        public Boolean TryGetValue(String name, out IXLNamedRange range)
        {
            if (_namedRanges.TryGetValue(name, out range)) return true;

            if (Worksheet != null)
                range = Worksheet.NamedRange(name);
            else
                range = Workbook.NamedRange(name);

            return range != null;
        }

        public Boolean Contains(String name)
        {
            if (_namedRanges.ContainsKey(name)) return true;

            if (Worksheet != null)
                return Worksheet.NamedRange(name) != null;
            else
                return Workbook.NamedRange(name) != null;
        }
    }
}