using ClosedXML.Excel;
using DocumentFormat.OpenXml.Drawing.Charts;
using DocumentFormat.OpenXml.Spreadsheet;
using paperless_ngx_export.Models;
using RBush;
using System;
using System.Collections.Generic;
using System.Text;

namespace paperless_ngx_export
{
    public static class spreadsheet
    {
        public static async Task<byte[]> GetSummarySpreadsheetAsByteArrayAsync()
        {
            byte[] bytes = null;

            using (var stream = new MemoryStream())
            {
                var workbook = await GetSummaryAsXLWorkbookAsync();
                workbook.SaveAs(stream);
                bytes = stream.ToArray();
                stream.Close();
            }

            return bytes ?? new byte[0];
        }

        public static void PopulateDocumentTypeWorksheets(
            IEnumerable<DocumentType> documentTypes,
            IEnumerable<Tag> tags,
            IEnumerable<CustomField> customFields,
            IEnumerable<DocumentParsed> docs,
            XLWorkbook workbook,
            bool onlyCurrentDocuments = true)
        {
            var headings = new string[]
            {
                "Correspondent",
                "Role",
                "Specialty",
                "Document Type",
                "Expiration Date",
                "Tags"
            };

            var documents = docs.Where(x =>
            {
                if (!x.CustomFields.Any(xx => xx.Name.Contains("expir", StringComparison.OrdinalIgnoreCase)))
                    return true;

                return onlyCurrentDocuments ? !x.Tags.Any(xx => xx.name.Contains("renewed", StringComparison.OrdinalIgnoreCase)) : true;
            }).ToList();

            foreach (var documentType in documentTypes.OrderBy(x=>!documents.Any(d=>d.DocumentType == x.name && d.CustomFields.Any(cf=>cf.Name.Contains("expir", StringComparison.OrdinalIgnoreCase)))).
                ThenBy(x=>x.name))
            {
                var sheetName = documentType.name.Replace('/', '-');
                var sheet = workbook.Worksheets.FirstOrDefault(x => x.Name == sheetName);
                if (sheet == null)
                {
                    sheet = workbook.Worksheets.Add(sheetName);
                    sheet.TabColor = XLColor.Green;

                    for (int i = 0; i < headings.Length; i++)
                    {
                        sheet.Cell(1, i + 1).Value = headings[i];
                    }

                    sheet.SheetView.Freeze(1, 2);
                    sheet.SetAutoFilter(true);
                    sheet.Cells("A1:ZZ1").Style.Font.Bold = true;
                }

                foreach (var document in documents.Where(x => x.DocumentType == documentType.name).OrderBy(x => x.Correspondent))
                {
                    var rowColour = XLColor.Transparent;
                    var expirationDate = document.CustomFields.FirstOrDefault(x => x.Name.Contains("expir", StringComparison.OrdinalIgnoreCase))?.DateValue;

                    if (expirationDate != null && expirationDate <= DateTime.Today)
                    {
                        rowColour = XLColor.Red;
                    }
                    else if (expirationDate != null && expirationDate?.AddDays(-30) < DateTime.Today)
                    {
                        rowColour = XLColor.Orange;
                    }

                    if(sheet.TabColor == XLColor.Green
                        && rowColour != XLColor.Transparent)
                    {
                        sheet.TabColor = sheet.TabColor == XLColor.Red ? XLColor.Red : rowColour;
                    }

                    var rowIndex = sheet.LastRowUsed()?.RowNumber() + 1 ?? 2;
                    sheet.Cell(rowIndex, 1).Value = document.Correspondent;
                    sheet.Cell(rowIndex, 2).Value = document.CustomFields.FirstOrDefault(x=>x.Name == "Role")?.StringValue;
                    sheet.Cell(rowIndex, 3).Value = document.CustomFields.FirstOrDefault(x => x.Name == "Specialty")?.StringValue;
                    sheet.Cell(rowIndex, 4).Value = document.DocumentType;
                    sheet.Cell(rowIndex, 5).Value = expirationDate == null ? Blank.Value : expirationDate;
                    sheet.Cell(rowIndex, 5).Style.Fill.BackgroundColor = rowColour == XLColor.Transparent ? sheet.Cell(rowIndex, 5).Style.Fill.BackgroundColor : rowColour;
                    sheet.Cell(rowIndex, 6).Value = String.Concat(document.Tags.Select(x=>x.name + ' ').ToArray()).Trim();
                }

                sheet.Columns().AdjustToContents();
            }
        }

        public static void PopulateSummaryWorksheet(
           IEnumerable<DocumentType> documentTypes,
           IEnumerable<Tag> tags,
           IEnumerable<CustomField> customFields,
           IEnumerable<DocumentParsed> docs,
           XLWorkbook workbook,
           bool onlyCurrentDocuments = true)
        {
            var headers = new string[]
                {
                "Correspondent",
                "Role (Specialty)",
                "Professional Registration",
                "Liability Insurance",
                "ACLS",
                "BLS",
                "PALS",
                "Vaccination Record",
                "CV / Resumé",
                "Misc Certificate",
                "Credentialing / Privileges",
                "Reference Letter"
                };

            var documents = docs.Where(x =>
            {
                if (!x.CustomFields.Any(xx => xx.Name.Contains("expir", StringComparison.OrdinalIgnoreCase)))
                    return true;

                return onlyCurrentDocuments ? !x.Tags.Any(xx => xx.name.Contains("renewed", StringComparison.OrdinalIgnoreCase)) : true;
            }).ToList();

            var summarySheet = workbook.Worksheets.Add("Summary");
            summarySheet.SheetView.Freeze(1, 2); //Freeze header row and, correspondent and role columns
            for (int i = 1; i <= headers.Length; i++)
            {
                summarySheet.Cell(1, i).Value = headers[i - 1];
            }
            summarySheet.Cells("A1:ZZ1").Style.Font.Bold = true;
            summarySheet.SetAutoFilter();

            var row = 2;
            foreach (var correspondent in documents.Select(x => x.Correspondent).Distinct())
            {
                summarySheet.Cell(row, 1).Value = correspondent;

                foreach (var doc in documents.Where(x => x.Correspondent == correspondent))
                {
                    if (summarySheet.Cell(row, 2).Value.Type == XLDataType.Blank)
                    {
                        var role = doc.CustomFields.FirstOrDefault(x => x.Name == "Role")?.Value?.ToString() ?? "";
                        var specialty = doc.CustomFields.FirstOrDefault(x => x.Name == "Specialty")?.Value?.ToString() ?? "";
                        role = $"{role} {(!string.IsNullOrWhiteSpace(specialty) ? $"({specialty})" : "")}".Trim();
                        summarySheet.Cell(row, 2).Value = role;
                    }

                    if (headers.IndexOf(doc.DocumentType.ToString()) + 1 is int column && column > 0)
                    {
                        XLCellValue cellValue = summarySheet.Cell(row, column).Value;

                        if (!cellValue.IsBlank)
                        {
                            continue;
                        }

                        if (doc.DocumentType == "Reference Letter")
                        {
                            cellValue = documents.Where(x => x.Correspondent == correspondent && x.DocumentType == "Reference Letter").Count();
                            ;
                        }
                        else if (doc.CustomFields.FirstOrDefault(x => x.Name == "Expiration Date") is CustomFieldParsed customFieldParsed &&
                            customFieldParsed.DateValue > DateTime.MinValue && customFieldParsed.DateValue < DateTime.MaxValue)
                        {
                            cellValue = XLCellValue.FromObject(customFieldParsed.DateValue);
                        }
                        else if (!doc.CustomFields.Any(x => x.Name == "Expiration Date"))
                        {
                            cellValue = "Present";
                        }

                        summarySheet.Cell(row, column).Value = cellValue;
                    }
                }

                row++;
            }

            summarySheet.Columns().AdjustToContents();            
        }

        public static async Task<XLWorkbook> GetSummaryAsXLWorkbookAsync()
        {
            var documenttypes = await api.getDocumentTypesAsync();
            var tags = await api.getTagsAsync();
            var customFields = await api.getCustomFieldsAsync();
            var documents = (await api.getMergedDocumentMetadataAsync(false, true)).Where(x => !x.CustomFields.Any(xx => xx.Name == "Action:Renewed")).OrderBy(x => x.Correspondent).ToList();
            var workbook = new XLWorkbook();

            PopulateSummaryWorksheet(documenttypes, tags, customFields, documents, workbook, true);
            PopulateDocumentTypeWorksheets(documenttypes, tags, customFields, documents, workbook, true);
            return workbook;
        }
    }
}