Imports DigitalData.GUIs.Common
Imports DigitalData.Modules.Base
Imports DigitalData.Modules.Logging
Imports DigitalData.Modules.ZooFlow
Imports System.Threading.Tasks

Public Class SearchRunner
    Inherits BaseClass

    Private Const SEARCH_FACT_DATE_DEFAULT As String = "ADDED_WHEN"

    Public Const CREATED_TOMORROW As String = "TOMORROW"
    Public Const CREATED_TODAY As String = "ECM_CREATED_TODAY"
    Public Const CREATED_YESTERDAY As String = "ECM_CREATED_YESTERDAY"
    Public Const CREATED_LAST_7_DAYS As String = "ECM_CREATED_LAST7DAYS"
    Public Const CREATED_YEAR_CURRENT As String = "ECM_CREATED_YEAR_CURRENT"
    Public Const CREATED_YEAR_LAST As String = "ECM_CREATED_YEAR_LAST"
    Public Const CREATED_MONTH_CURR As String = "ECM_CREATED_MONTH_CURRENT"
    Public Const CREATED_MONTH_LAST As String = "ECM_CREATED_MONTH_LAST"

    Public Enum DateConstraint
        Today
        Tomorrow
        Yesterday
        Last7Days
        CurrentMonth
        LastMonth
        CurrentYear
        LastYear
        Undefined
    End Enum

    Public Enum TokenOperator
        [And]
        [Or]
    End Enum

    Public Event NeedsRefresh As EventHandler(Of Integer)
    Public Event Closed As EventHandler(Of Integer)

    Private Property _ActiveDateConstraint As String = String.Empty
    Public ReadOnly Property ActiveDateConstraint As String
        Get
            Return _ActiveDateConstraint
        End Get
    End Property

    Private _ActiveDateAttribute As String = SEARCH_FACT_DATE_DEFAULT
    Private _ActiveTokenOperator As TokenOperator = TokenOperator.And

    Public ReadOnly Property ActiveDateAttribute As String
        Get
            Return _ActiveDateAttribute
        End Get
    End Property

    Public Property BaseSearchSQL As String
    Public Property ExplicitDate As Boolean = False

    Private ReadOnly Environment As Environment
    Private ReadOnly SearchId As String
    Private ReadOnly UserId As Integer
    Private ReadOnly UserLanguage As String

    Public Sub New(pLogConfig As LogConfig, pEnvironment As Environment, pSearchId As String)
        MyBase.New(pLogConfig)
        Environment = pEnvironment
        SearchId = pSearchId
        UserId = My.Application.User.UserId
        UserLanguage = My.Application.User.Language
    End Sub

    Public Function RunWithDataTable(pDatatable As DataTable) As SearchResult
        Return RunWithDataTable(pDatatable, "Suche")
    End Function

    Public Function RunWithDataTable(pDatatable As DataTable, pTitle As String) As SearchResult
        Dim oParams = GetParams(pTitle)
        oParams.Results.Add(New DocumentResultList.DocumentResult() With {
            .Title = pTitle,
            .Datatable = pDatatable
        })

        If pDatatable.Rows.Count = 1 Then
            oParams.ShowFileList = False
        End If

        Dim oForm As New frmDocumentResultList(My.LogConfig, Environment, oParams)

        ' TODO: Implement, not needed right now
        'AddHandler oForm.NeedsRefresh, AddressOf Form_NeedsRefresh
        AddHandler oForm.FormClosed, AddressOf Form_Closed

        oForm.Show()

        Return New SearchResult(pDatatable.Rows.Count)
    End Function

    ''' <summary>
    ''' Only search for Term. Used for sidebar quicksearch.
    ''' </summary>
    Public Async Function RunWithSearchTerm(pSearchTerm As String) As Task(Of SearchResult)
        Return Await RunWithSearchTerm(New SearchOptions With {.SearchString = pSearchTerm})
    End Function

    Public Async Function RunWithSearchTerm(pSearchTerm As String, pDateFrom As Date, pDateTo As Date, pSearchTitle As String) As Task(Of SearchResult)
        Return Await RunWithSearchTerm(New SearchOptions With {
                                           .SearchString = pSearchTerm,
                                           .SearchTitle = pSearchTitle,
                                           .DateFrom = pDateFrom,
                                           .DateTo = pDateTo
                                       })
    End Function

    Public Async Function RunWithTokens(pTokens As IEnumerable(Of Search.SearchToken.Token)) As Task(Of SearchResult)
        Return Await RunWithSearchTerm(New SearchOptions With {
                                            .SearchTokens = pTokens
                                       })
    End Function

    Public Async Function RunWithTokens(pTokens As IEnumerable(Of Search.SearchToken.Token), pDateFrom As Date, pDateTo As Date, pSearchTitle As String) As Task(Of SearchResult)
        If pTokens.Count = 0 And
            pDateFrom = Date.MinValue And
            pDateTo = Date.MinValue And
            _ActiveDateConstraint = String.Empty Then
            Return New SearchResult(0)
        End If

        Return Await RunWithSearchTerm(New SearchOptions With {
                                            .SearchTokens = pTokens,
                                            .DateFrom = pDateFrom,
                                            .DateTo = pDateTo
                                       })
    End Function


    'Public Async Function RunWithSearchTerm(pSearchTerm As String, pDateFrom As Date, pDateTo As Date) As Task(Of SearchResult)
    '    Return Await RunWithSearchTerm(pSearchTerm, pDateFrom, pDateTo, Nothing, Nothing)
    'End Function

    Private Async Function RunWithSearchTerm(pOptions As SearchOptions) As Task(Of SearchResult)
        Dim oDateConstraint = Await GetDateConstraint(pOptions.DateFrom, pOptions.DateTo)
        Dim oWindowTitle = GetResultWindowString(pOptions.SearchString, pOptions.SearchTitle)
        Dim oParams = GetParams(oWindowTitle)
        Dim oTokens = pOptions.SearchTokens
        Dim oSearchTerm = pOptions.SearchString

        Dim oSQL

        If oTokens IsNot Nothing AndAlso oTokens.Count > 0 Then
            Await InsertSearchTokens(oTokens)
            oSQL = $"EXEC PRIDB_SEARCH_GET_TOKEN_RESULT_DOCS {UserId}, '{oDateConstraint}', '{UserLanguage}'"
        ElseIf oSearchTerm IsNot Nothing Then
            oSQL = $"EXEC PRIDB_SEARCH_GET_TEXT_RESULTS {UserId},'{pOptions.SearchString}','{oDateConstraint}', '{UserLanguage}'"
        Else
            oSQL = $"EXEC PRIDB_SEARCH_GET_TEXT_RESULTS {UserId},'{String.Empty}','{oDateConstraint}', '{UserLanguage}'"
        End If

        If Await My.Database.ExecuteNonQueryIDBAsync(oSQL) = True Then
            Dim oDTDocResult = Await My.Database.GetDatatableIDBAsync(BaseSearchSQL)

            If oDTDocResult Is Nothing Then
                Return New SearchResult("Error in Search Query")
            End If

            Dim oRowCount = oDTDocResult.Rows.Count
            If oRowCount > 0 Then
                oParams.Results.Add(New DocumentResultList.DocumentResult() With {
                    .Title = SearchId,
                    .Datatable = oDTDocResult
                })

                If oDTDocResult.Rows.Count = 1 Then
                    oParams.ShowFileList = False
                End If

                Dim oForm As New frmDocumentResultList(My.LogConfig, Environment, oParams)

                ' TODO: Implement
                'AddHandler oForm.NeedsRefresh, AddressOf Form_NeedsRefresh
                AddHandler oForm.FormClosed, AddressOf Form_Closed

                oForm.Show()

                Return New SearchResult(oRowCount)
            Else
                Return New SearchResult(oRowCount)

            End If
        Else
            Return New SearchResult("Error in Search Function")

        End If
    End Function

    Private Async Function GetDateConstraint(pDateFrom As Date, pDateTo As Date) As Task(Of String)
        Dim oSimpleDateConstraint = $"{_ActiveDateAttribute}~{_ActiveDateConstraint}"
        Dim oExplicitConstraint = Await MaybeSetExplicitDateConstraint(pDateFrom, pDateTo)

        If IsNothing(oExplicitConstraint) Then
            Return oSimpleDateConstraint
        Else
            Return oExplicitConstraint
        End If
    End Function

    Private Async Function InsertSearchTokens(pTokens As IEnumerable(Of Search.SearchToken.Token)) As Task
        Logger.Debug("Deleting previous user tokens..")
        Await My.Database.ExecuteNonQueryIDBAsync($"DELETE FROM TBIDB_SEARCH_INPUT_USER WHERE USR_ID = {UserId}")

        If pTokens Is Nothing Then
            Logger.Warn("Token Object was nothing!")
            Exit Function
        End If

        If pTokens.Count = 0 Then
            Logger.Warn("Token Object was empty!")
            Exit Function
        End If

        Dim oOperatorString

        Select Case _ActiveTokenOperator
            Case TokenOperator.Or
                oOperatorString = "OR"
            Case Else
                oOperatorString = "AND"
        End Select


        For Each oToken In pTokens
            Dim oSQLInsert As String = $"
                    INSERT INTO [dbo].[TBIDB_SEARCH_INPUT_USER] ([USR_ID], [ATTR_ID], [ATTR_TITLE], [TERM_ID], [OPERATOR])
                    VALUES ({UserId}, {oToken.AttributeId}, '{oToken.AttributeTitle}', {oToken.TermId}, '{oOperatorString}')"

            Dim oResult = Await My.Database.ExecuteNonQueryIDBAsync(oSQLInsert)
            Logger.Warn("Inserting Tokens failed!")
        Next
    End Function


    Private Async Function MaybeSetExplicitDateConstraint(pDateFrom As Date, pDateTo As Date) As Task(Of String)
        If pDateFrom.Equals(Date.MinValue) = False Then
            ExplicitDate = True

            Dim oDateTo As Date
            If pDateTo.Equals(Date.MinValue) Then
                oDateTo = pDateFrom
            Else
                oDateTo = pDateTo
            End If
            Dim oProc = $"EXEC PRIDB_SEARCH_ADD_USR_DATE {UserId},'{pDateFrom}','{oDateTo}'"
            If Await My.Database.ExecuteNonQueryIDBAsync(oProc) = True Then
                Return $"{_ActiveDateAttribute}~DATEPART"
            Else
                Return Nothing
            End If
        End If

        Return Nothing
    End Function

    Private Sub Form_Closed(sender As Object, e As EventArgs)
        RaiseEvent Closed(sender, 0)
    End Sub

    Private Function GetParams(pWindowTitle As String) As DocumentResultList.Params
        Dim oParams = New DocumentResultList.Params() With {
            .WindowGuid = SearchId,
            .WindowTitle = pWindowTitle,
            .OperationModeOverride = Modules.ZooFlow.Constants.OperationMode.ZooFlow,
            .ProfileGuid = 35452,
            .ColumnNames = New DocumentResultList.ColumnNames With {
                .ObjectIdColumn = "DocID"
            },
            .ShowBackNavigation = False
        }
        Return oParams
    End Function

    Private Function GetResultWindowString(pSearchContent As String, pWindowTitle As String) As String
        Dim oWindowString

        ' This is the default title
        If UserLanguage = State.UserState.LANG_DE_DE Then
            oWindowString = $"Suche"
        Else
            oWindowString = $"Search"
        End If

        ' If a Search String is given, we might take this
        If pSearchContent <> String.Empty Then
            If UserLanguage = State.UserState.LANG_DE_DE Then
                Return $"Suche Nach '{pSearchContent}'"
            Else
                Return $"Search For '{pSearchContent}'"
            End If
        End If

        ' Window Title overrides everything
        If pWindowTitle IsNot Nothing Then
            oWindowString = pWindowTitle
        End If

        Return oWindowString
    End Function

    Public Sub SetDateConstraint()
        _ActiveDateConstraint = String.Empty
    End Sub

    Public Sub SetDateConstraint(pConstraintName As String)
        _ActiveDateConstraint = pConstraintName
    End Sub

    Public Sub SetDateConstraint(pConstraint As DateConstraint)
        _ActiveDateConstraint = DateConstraintToConstant(pConstraint)
    End Sub

    Public Sub SetTokenOperator(pOperator As TokenOperator)
        _ActiveTokenOperator = pOperator
    End Sub

    Public Function DateConstraintToConstant(pConstraint As DateConstraint) As String
        Select Case pConstraint
            Case DateConstraint.Today
                Return CREATED_TODAY

            Case DateConstraint.Yesterday
                Return CREATED_YESTERDAY

            Case DateConstraint.Tomorrow
                Return CREATED_TOMORROW

            Case DateConstraint.Last7Days
                Return CREATED_LAST_7_DAYS

            Case DateConstraint.CurrentMonth
                Return CREATED_MONTH_CURR

            Case DateConstraint.LastMonth
                Return CREATED_MONTH_LAST

            Case DateConstraint.CurrentYear
                Return CREATED_YEAR_CURRENT

            Case DateConstraint.LastYear
                Return CREATED_YEAR_LAST

            Case Else
                Return String.Empty

        End Select
    End Function
    Public Function ConstantToDateConstraint(pConstant As String) As DateConstraint
        Select Case pConstant
            Case CREATED_TODAY
                Return DateConstraint.Today
            Case CREATED_YESTERDAY
                Return DateConstraint.Yesterday
            Case CREATED_TOMORROW
                Return DateConstraint.Tomorrow
            Case CREATED_LAST_7_DAYS
                Return DateConstraint.Last7Days
            Case CREATED_MONTH_CURR
                Return DateConstraint.CurrentMonth
            Case CREATED_MONTH_LAST
                Return DateConstraint.LastMonth
            Case CREATED_YEAR_CURRENT
                Return DateConstraint.CurrentYear
            Case CREATED_YEAR_LAST
                Return DateConstraint.LastYear
            Case Else
                Return DateConstraint.Undefined
        End Select
    End Function

    Public Sub SetDateAttribute(pAttributeName As String)
        _ActiveDateAttribute = pAttributeName
    End Sub

    Public Sub SetDateAttribute()
        _ActiveDateAttribute = SEARCH_FACT_DATE_DEFAULT
    End Sub

    Public Class SearchOptions
        Public SearchTitle As String

        Public SearchString As String
        Public SearchTokens As IEnumerable(Of Search.SearchToken.Token)

        Public DateFrom As Date
        Public DateTo As Date
    End Class

    Public Class SearchResult
        Public OK As Boolean = True
        Public Count As Integer = 0
        Public ErrorMessage As String = String.Empty

        ''' <summary>
        ''' Returns a positive Search Result
        ''' </summary>
        Public Sub New(pCountResults As Integer)
            Count = pCountResults
        End Sub

        ''' <summary>
        ''' Returns a failed search result with an error message
        ''' </summary>
        ''' <param name="pMessage"></param>
        Public Sub New(pMessage As String)
            OK = False
            ErrorMessage = pMessage
        End Sub
    End Class
End Class