Option Strict Off
Option Explicit Off

Imports EnvDTE
Imports EnvDTE80
Imports System.Diagnostics
Imports Microsoft.VisualBasic
Imports Microsoft.VisualBasic.ControlChars

Public Module HtmlEntitiesAutocomplete

    Dim ParamArr() As String
    Dim previousSelection As String
    Dim completionWords As String
    Dim completionWordsIndex As Integer


    ' Auto-completion macro.

    Sub AddToCompletionWords(ByVal word As String)
        ' If the word is already there, abort.
        If InStr(1, completionWords, " " & word & " ", 1) <> 0 Then
            Exit Sub
        End If

        If word <> " " Then
            completionWords = completionWords & word & " "
        End If

    End Sub

    Private Function ExtractNextCompletionWord()
        ExtractNextCompletionWord = ""

        ' If no words yet, go away.
        If Len(completionWords) <= 1 Then
            Exit Function
        End If

        ' Wrap to beginning if necessary.
        If completionWordsIndex > Len(completionWords) Then
            completionWordsIndex = 2
        End If

        ' Find next <space>.
        Dim newIndex As Integer
        newIndex = InStr(completionWordsIndex, completionWords, " ", 0)
        If newIndex = 0 Then
            Exit Function
        End If

        ExtractNextCompletionWord = Mid(completionWords, completionWordsIndex, newIndex - completionWordsIndex)
        completionWordsIndex = newIndex + 1 ' Skip over <space>.

    End Function

    Sub FillCompletionWords(ByVal word As String)
        '  Find all words in this file which match word, and
        '   add them, space separated, to completionWords.
        previousSelection = word
        completionWords = " "
        completionWordsIndex = 2
        Dim sel As EnvDTE.TextSelection

        sel = DTE.ActiveDocument.Selection

        Dim searchString As String
        searchString = "[^a-zA-Z0-9]" & word
        Dim firstTime As Boolean
        firstTime = True
        Dim firstLine, firstCol As Integer
        sel.StartOfDocument()

        Do While sel.FindText(searchString, vsFindOptions.vsFindOptionsRegularExpression)
            If firstTime Then
                firstLine = sel.TopLine
                firstCol = sel.CurrentColumn
                firstTime = False
            ElseIf firstLine = sel.TopLine And firstCol = sel.CurrentColumn Then
                Exit Do ' Jump out of loop before repeat.
            End If
            sel.WordRight()
            sel.WordLeft(DsMovementOptions.dsExtend)
            AddToCompletionWords(Trim(sel.Text))
            sel.Cancel()
        Loop
    End Sub

    Function SuggestNextCompletionWord()
        SuggestNextCompletionWord = True
        Dim selection As EnvDTE.TextSelection
        Dim word As String

        selection = DTE.ActiveDocument.Selection
        word = ExtractNextCompletionWord()
        If word <> "" Then
            selection.Text = word
            previousSelection = word
        End If

        selection.WordLeft(DsMovementOptions.dsExtend)
    End Function

    Sub AutoCompleteHtmlEntities()

        ' DESCRIPTION: Looks through the active file, searching for the rest of the word that you began to type.
        Dim doc As EnvDTE.Document
        Dim sel As EnvDTE.TextSelection
        Dim origLine, origCol As Integer
        doc = DTE.ActiveDocument

        completionWords = "&nbsp; &gt; &lt; &ggt; &gggt"

        ' Be sure active document is a text document.
        If doc Is Nothing Then
            Exit Sub
        ElseIf doc.Type <> "Text" Then
            Exit Sub
        End If

        ' Get word to be completed.
        sel = doc.Selection
        sel.Cancel()
        origLine = sel.CurrentLine
        origCol = sel.CurrentColumn
        sel.WordLeft(DsMovementOptions.dsExtend)

        ' If the cursor is sitting just to the right of a space, an infinite loop
        ' results. This bit of code protects from that:
        If Right(sel.Text, 1) = " " Then
            sel.CharRight()
            Exit Sub
        End If

        FillCompletionWords(sel.Text)
        sel.MoveToLineAndOffset(origLine, origCol)
        sel.WordLeft(DsMovementOptions.dsExtend)
        SuggestNextCompletionWord()

    End Sub
End Module