/***************************************************************************

Copyright (c) Microsoft Corporation 2011.

This code is licensed using the Microsoft Public License (Ms-PL).  The text of the license can be found here:

http://www.microsoft.com/resources/sharedsource/licensingbasics/publiclicense.mspx

***************************************************************************/

using System.Collections.Generic;
using System.Linq;
using System.Xml.Linq;
using DocumentFormat.OpenXml.Packaging;
using System;
using System.Xml;

namespace OpenXmlPowerTools
{
    /// <summary>
    /// Class for working with the Table Definition Part for a SpreadsheetML document
    /// </summary>
    public class SpreadSheetTableAccessor
    {
        private static XNamespace ns;
        private static XNamespace relationshipns;

        /// <summary>
        /// Static constructor
        /// </summary>
        static SpreadSheetTableAccessor()
        {
            ns = "http://schemas.openxmlformats.org/spreadsheetml/2006/main";
            relationshipns = "http://schemas.openxmlformats.org/officeDocument/2006/relationships";    
        }

        /// <summary>
        /// Method for adding a new table definition part
        /// </summary>
        /// <param name="worksheet">Worksheet to add the table to</param>
        /// <param name="tableStyle">Style to be assigned to the table</param>
        /// <param name="useHeaders">Set a header row</param>
        /// <param name="fromColumn">Initial column for table</param>
        /// <param name="toColumn">Final column for table</param>
        /// <param name="fromRow">Intial row for table</param>
        /// <param name="toRow">Final row for table</param>
        public static OpenXmlPowerToolsDocument Add(SmlDocument doc, string worksheetName, string tableStyle, bool useHeaders, short fromColumn, short toColumn, int fromRow, int toRow)
        {
            using (OpenXmlMemoryStreamDocument streamDoc = new OpenXmlMemoryStreamDocument(doc))
            {
                using (SpreadsheetDocument document = streamDoc.GetSpreadsheetDocument())
                {
                    //Getting the id for this table
                    int tableId = GetNextTableId(document);

                    //Set the table cell range
                    string tableRange = string.Format("{0}{1}:{2}{3}", WorksheetAccessor.GetColumnId(fromColumn),
                                                                      fromRow,
                                                                      WorksheetAccessor.GetColumnId(toColumn),
                                                                      toRow);

                    //Creating a new id for the relationship between the table definition part and the worksheet
                    string tableRelationShipId = "rId" + Guid.NewGuid();

                    //Create a new table definition part
                    WorksheetPart worksheet = WorksheetAccessor.Get(document, worksheetName);
                    TableDefinitionPart table = worksheet.AddNewPart<TableDefinitionPart>(tableRelationShipId);

                    //string tableColumns = string.Empty;
                    XElement tableColumnsXElement = new XElement(ns + "tableColumns", new XAttribute("count", (toColumn - fromColumn) + 1));
                    //Get the name for table column elements from the first table row
                    string[] tableHeaders = GetTableHeaders(document, worksheet, fromRow, fromColumn, toColumn);
                    for (int i = 0; i <= (toColumn - fromColumn); i++)
                    {
                        //Create the markup for the SpreadsheetML table column elements
                        tableColumnsXElement.Add(
                            new XElement(ns + "tableColumn", new XAttribute("id", i + 1), new XAttribute("name", tableHeaders[i])));

                    }

                    XElement tableXElement =
                        new XElement(ns + "table",
                            new XAttribute("xmlns", ns), //default namespace
                            new XAttribute("id", tableId),
                            new XAttribute("name", "Table" + tableId.ToString()),
                            new XAttribute("displayName", "Table" + tableId.ToString()),
                            new XAttribute("ref", tableRange),
                            new XAttribute("totalsRowShown", "0"));

                    if (useHeaders)
                    {
                        tableXElement.Add(
                            new XElement(ns + "autoFilter", new XAttribute("ref", tableRange)));
                    }

                    tableXElement.Add(tableColumnsXElement);

                    tableXElement.Add(
                        new XElement(ns + "tableStyleInfo",
                        new XAttribute("name", tableStyle),
                        new XAttribute("showFirstColumn", "0"),
                        new XAttribute("showLastColumn", "0"),
                        new XAttribute("showRowStripes", "0"),
                        new XAttribute("showColumnStripes", "0")));

                    //Write the markup to the Table Definition Part Stream
                    XmlWriter tablePartStreamWriter = XmlWriter.Create(table.GetStream());
                    tableXElement.WriteTo(tablePartStreamWriter);

                    tablePartStreamWriter.Flush();
                    tablePartStreamWriter.Close();

                    //Create or modify the table parts definition at worksheet (for setting the relationship id with the new table)
                    XDocument worksheetMarkup = worksheet.GetXDocument();
                    //Look for the tableParts element at worksheet markup
                    XElement tablePartsElement = worksheetMarkup.Root.Element(ns + "tableParts");
                    if (tablePartsElement != null)
                    {
                        //tableParts elements does exist at worksheet markup
                        //increment the tableParts count attribute value
                        short tableCount = System.Convert.ToInt16(tablePartsElement.Attribute("count").Value);
                        tablePartsElement.SetAttributeValue("count", tableCount++.ToString());

                    }
                    else
                    {
                        //tableParts does not exist at worksheet markup
                        //create a new tableParts element
                        tablePartsElement = new XElement(ns + "tableParts",
                                                                       new XAttribute(ns + "count", "1"));

                        worksheetMarkup.Root.Add(tablePartsElement);
                    }

                    //create the tablePart element
                    XElement tablePartEntryElement = new XElement(ns + "tablePart",
                                                                      new XAttribute(relationshipns + "id", tableRelationShipId));

                    //add the new tablePart element to the worksheet tableParts element
                    tablePartsElement.Add(tablePartEntryElement);
                    worksheet.PutXDocument();
                }
                return streamDoc.GetModifiedDocument();
            }
        }

        /// <summary>
        /// Returns the id for the next table to add to the SpreadSheetML document
        /// </summary>
        /// <returns></returns>
        private static int GetNextTableId(SpreadsheetDocument document)
        {
            int tableCount = 0;
            foreach (WorksheetPart worksheet in document.WorkbookPart.WorksheetParts)
            {  //Loop the worksheets to sum up the tables defined in each one
                tableCount += worksheet.TableDefinitionParts.Count();
            }
            return ++tableCount;
        }

        /// <summary>
        /// Get the values for the table header row (table initial row)
        /// </summary>
        /// <param name="worksheet">Worksheet where the table is being defined</param>
        /// <param name="row">Table initial row</param>
        /// <param name="fromColumn">Table initial column</param>
        /// <param name="toColumn">Table final column</param>
        /// <returns></returns>
        private static string[] GetTableHeaders(SpreadsheetDocument document, WorksheetPart worksheet, int row, short fromColumn, short toColumn)
        {
            List<string> tableHeaders = new List<string>();
            for (short c = fromColumn; c <= toColumn; c++)
            {
                tableHeaders.Add(WorksheetAccessor.GetValue(document, worksheet, c, row));
            }

            return tableHeaders.ToArray<string>();
        }
    }
}