using System;
using System.Collections.Generic;
using System.Net;
using Neo.Afx.ComponentModel;
using System.Linq;
using Neo.Afx.Services.Reports;
using DevExpress.XtraReports.UI;
using System.IO;

namespace Neo.Afx.Services.Reports
{
    ///<summary>
    /// Report generator static class
    ///</summary>
    public static class ReportGenerator
    {
        #region Constants        
        /// <summary>
        /// CSV file format type for this report mime type
        /// </summary>
        public const string FORMAT_CSV = "CSV";

        /// <summary>
        /// EXCEL file format type for this report mime type
        /// </summary>
        public const string FORMAT_EXCEL = "EXCEL";
        
        /// <summary>
        /// PDF file format type for this report mime type
        /// </summary>
        public const string FORMAT_PDF = "PDF";

        #endregion

        #region GetMimeTypeForFormat
        /// <summary>
        /// Gets the MIME type for format.
        /// </summary>
        /// <param name="format">The format.</param>
        /// <returns></returns>
        public static string GetMimeTypeForFormat(string format)
        {
            switch(format)
            {
                case FORMAT_CSV:
                    return "text/csv";
                case FORMAT_EXCEL:
                    return "application/msexcel";
                case FORMAT_PDF:
                    return "application/pdf";
            }
            return "application/octet-stream";
        }
        #endregion

        #region RenderPdf
        /// <summary>
        /// Renders the given report as a PDF.
        /// </summary>
        /// <param name="reportDefinition"></param>
        /// <param name="error">When this method returns, contains the error message if an error occurred.</param>
        /// <param name="reportParameters">The report parameters.</param>
        /// <returns>The content of the report or <code>null</code> if an error occurred.</returns>
        public static byte[] RenderPdf(ReportDefinition reportDefinition, List<KeyValuePair<string, string>> reportParameters, out string error)
        {
            return Render(reportDefinition, FORMAT_PDF, reportParameters, out error);
        }
        #endregion

        #region RenderXL
        /// <summary>
        /// Renders the given report as a EXCEL.
        /// </summary>
        /// <param name="reportDefinition"></param>
        /// <param name="error">When this method returns, contains the error message if an error occurred.</param>
        /// <param name="reportParameters">The report parameters.</param>
        /// <returns>The content of the report or <code>null</code> if an error occurred.</returns>
        public static byte[] RenderXl(ReportDefinition reportDefinition, List<KeyValuePair<string, string>> reportParameters, out string error)
        {
            return Render(reportDefinition, FORMAT_EXCEL, reportParameters, out error);
        }
        #endregion

        #region Render
        /// <summary>
        /// Renders the given report in the specified format.
        /// </summary>
        /// <param name="reportDefinition"></param>
        /// <param name="format">The format in which the report is to be rendered.</param>
        /// <param name="error">When this method returns, contains the error message if an error occurred.</param>
        /// <param name="reportParameters">The report parameters.</param>
        /// <returns>The content of the report or <code>null</code> if an error occurred.</returns>
        public static byte[] Render(ReportDefinition reportDefinition, string format, List<KeyValuePair<string, string>> reportParameters, out string error)
        {
            error = null;
            
            try
            { 
                var assembly = reportDefinition.Server.Url;
                var typename = assembly + "." + reportDefinition.ReportFolder + "." + reportDefinition.ReportName;
                var temp = Type.GetType(typename + ", " + assembly);
                var report = (XtraReport)Activator.CreateInstance(Type.GetType(typename + ", " + assembly));

                foreach (var p in reportParameters)
                {                    
                    report.Parameters[p.Key].Value = p.Value;
                }

                using (MemoryStream localStream = new MemoryStream())
                { 
                    if (format == FORMAT_EXCEL)
                    { 
                        report.ExportToXlsx(localStream);    
                    }
                    else if (format == FORMAT_PDF)
                    { 
                        report.ExportToPdf(localStream);        
                    }
                    else if (format == FORMAT_CSV)
                    { 
                        report.ExportToCsv(localStream);        
                    }
                    else
                    { 
                        throw new Exception("Invalid report format specified:" + format);
                    }

                    return localStream.ToArray();                    
                }
            }
            catch (Exception ex)
            { 
                error = (ex.Message.IndexOf("Inner Exception") != -1 ? ex.InnerException.Message : ex.Message);
            }

            return null;
        }
        #endregion
    }

    #region Report

    /// <summary>
    /// A report object.
    /// </summary>
    public class Report : FileObject
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="Report"/> class.
        /// </summary>
        public Report()
        {
        }

        /// <summary>
        /// Determines whether the report has content.
        /// </summary>
        public bool HasContent
        {
            get
            {
                return Content != null;
            }
        }

        /// <summary>
        /// Gets the content length.
        /// </summary>
        public new long Length
        {
            get
            {
                return Content == null ? 0 : Content.LongLength;
            }
        }

        /// <summary>
        /// The error (if any) that occurred during report generation
        /// </summary>
        public string Error;

        /// <summary>
        /// Creates a report with the given name, extension and mime type.
        /// </summary>
        /// <param name="name">The name of the report.</param>
        /// <param name="extension">The extension of the report.</param>
        /// <param name="mimeType">The mime type of the report.</param>
        /// <returns>A new report object.</returns>
        public static Report Create(string name, string extension, string mimeType)
        {
            return new Report
            {
                Name = name,
                Extension = extension,
                MimeType = mimeType
            };
        }
    }

    #endregion
}