Imports System.IO
Imports DigitalData.Modules.Database
Imports DigitalData.Modules.Logging
Imports MultiTool.Shared.Winline
Imports MultiTool.Shared.Helpers

Namespace Schemas
    Public Class SchemaLoader
        Inherits BaseClass

        Private ReadOnly ns As XNamespace = "http://www.w3.org/2001/XMLSchema"

        Public SchemaList As List(Of Schema)
        Public TemplateConfiguration As New Configuration

        Private ReadOnly Database As MSSQLServer

        Private Const VWEDI_XML_ITEMS = "VWEDI_XML_ITEMS"

        Public Sub New(pLogConfig As LogConfig, pMSSQL As MSSQLServer)
            MyBase.New(pLogConfig, pLogConfig.GetLogger)
            Database = pMSSQL
        End Sub

        Public Async Function LoadTemplates() As Task(Of Boolean)
            Try
                Dim oSql = $"SELECT * FROM [DD_ECM].[dbo].[TBEDI_XML_TEMPLATES]"
                Dim oTable As DataTable = Await Database.GetDatatableAsync(oSql)
                Dim oTemplates As New List(Of Schema)

                For Each oRow As DataRow In oTable.Rows
                    Dim oTemplate As New Schema With {
                        .Name = GetRowItem(oRow, "NAME", String.Empty),
                        .Description = GetRowItem(oRow, "DESCRIPTION", String.Empty),
                        .FileName = GetRowItem(oRow, "FILE_NAME", String.Empty),
                        .IsImport = GetRowItem(oRow, "IS_IMPORT", True)
                    }

                    oTemplates.Add(oTemplate)
                Next

                SchemaList = oTemplates

                Return True
            Catch ex As Exception
                Logger.Error(ex)
                Return False

            End Try
        End Function

        Public Async Function LoadTemplateConfiguration() As Task(Of Boolean)
            Try
                Dim oSql = $"SELECT * FROM [DD_ECM].[dbo].[{VWEDI_XML_ITEMS}]"
                Dim oTable As DataTable = Await Database.GetDatatableAsync(oSql)
                Dim oItems As New List(Of ColumnConfig)

                For Each oRow As DataRow In oTable.Rows
                    Dim oColumn As New ColumnConfig() With {
                        .Template = GetRowItem(oRow, "TEMPLATE_NAME", String.Empty),
                        .Table = GetRowItem(oRow, "XML_TABLE", String.Empty),
                        .Name = GetRowItem(oRow, "XML_ITEM", String.Empty),
                        .Type = ColumnConfig.ConvertType(GetRowItem(oRow, "DATA_TYPE", String.Empty)),
                        .OrderKey = GetRowItem(oRow, "ORDER_KEY", 0),
                        .IsReadOnly = GetRowItem(oRow, "IS_READ_ONLY", False),
                        .IsVisible = GetRowItem(oRow, "IS_VISIBLE", True),
                        .IsRequired = GetRowItem(oRow, "IS_REQUIRED", False),
                        .IsHead = GetRowItem(oRow, "IS_HEAD", True),
                        .[Function] = New ColumnConfig.ColumnFunction With {
                            .Id = GetRowItem(oRow, "FUNCTION_ID", 0),
                            .Name = GetRowItem(oRow, "FUNCTION_NAME", String.Empty),
                            .Params = GetRowItem(oRow, "FUNCTION_PARAMETERS", String.Empty)
                        }
                    }

                    oItems.Add(oColumn)
                Next

                TemplateConfiguration = New Configuration With {
                    .Columns = oItems
                }

                Return True

            Catch ex As Exception
                Logger.Error(ex)
                Return False

            End Try
        End Function

        Public Function UpdateSchemaFromFile(pSchema As Schema, pInputDirectory As String) As Schema
            Dim oFullPath = Path.Combine(pInputDirectory, pSchema.FileName)

            If Not IO.File.Exists(oFullPath) Then
                Throw New FileNotFoundException(oFullPath)
            End If

            Dim oElements = GetSchemaElements(oFullPath)

            For Each oElement In oElements
                Dim oColumns = GetElementColumns(oElement)
                Dim oSchemaColumns As New List(Of Schema.Column)

                For Each oColumn As XElement In oColumns
                    Dim oName = XmlData.GetElementAttribute(oColumn, "name")
                    Dim oMinOccurs = XmlData.GetElementAttribute(oColumn, "minOccurs")
                    Dim oMaxOccurs = XmlData.GetElementAttribute(oColumn, "maxOccurs")
                    Dim oType = GetElementType(oColumn)
                    Dim oRequired = False

                    If oMinOccurs = 1 And oMaxOccurs = 1 Then
                        oRequired = True
                    End If

                    Dim oSchemaColumn As New Schema.Column With {
                        .Name = oName,
                        .DataType = oType,
                        .IsRequired = oRequired
                    }
                    oSchemaColumns.Add(oSchemaColumn)
                Next

                pSchema.Tables.Add(New Schema.Table With {
                    .Name = XmlData.GetElementAttribute(oElement, "name"),
                    .Columns = oSchemaColumns
                })

            Next

            Return pSchema
        End Function

        Public Function UpdateSchemaFromDatabase(pSchema As Schema, pTemplateConfig As Configuration) As Schema
            If pTemplateConfig Is Nothing Then
                Return pSchema
            End If

            For Each oTable In pSchema.Tables
                For Each oColumn As Schema.Column In oTable.Columns
                    Dim oConfig = pTemplateConfig.GetColumn(oColumn.Name)

                    If oConfig Is Nothing Then
                        oConfig = New ColumnConfig With {
                            .IsRequired = oColumn.IsRequired,
                            .Name = oColumn.Name
                        }
                    End If

                    oColumn.Config = oConfig
                Next
            Next

            Return pSchema
        End Function

        Public Function GetElementType(pElement As XElement) As Constants.ColumnType
            Dim oTypeString = XmlData.GetElementAttribute(pElement, "type")

            If oTypeString Is Nothing Then
                Dim oRestrictionElement As XElement = pElement.
                    Descendants(ns + "restriction").
                    FirstOrDefault()

                oTypeString = XmlData.GetElementAttribute(oRestrictionElement, "base")
            End If

            Select Case oTypeString
                Case Constants.SCHEMA_TYPE_DATE
                    Return Constants.ColumnType.Date
                Case Constants.SCHEMA_TYPE_INTEGER
                    Return Constants.ColumnType.Integer
                Case Constants.SCHEMA_TYPE_DECIMAL
                    Return Constants.ColumnType.Decimal
                Case Constants.SCHEMA_TYPE_BOOLEAN
                    Return Constants.ColumnType.Boolean
                Case Else
                    Return Constants.ColumnType.String
            End Select
        End Function

        Public Function GetSchemaElements(pSchemaFilePath As String) As List(Of XElement)
            Dim oText As String = IO.File.ReadAllText(pSchemaFilePath)
            Dim oDoc = XDocument.Parse(oText)

            Return XmlData.GetElementsFromElement(oDoc, "choice", ns)
        End Function

        Public Function GetElementColumns(pElement As XElement) As List(Of XElement)
            Return XmlData.GetElementsFromElement(pElement, "sequence", ns)
        End Function
    End Class

End Namespace