Imports System.IO
Imports System.Net
Imports Newtonsoft.Json.Linq

Module Module1

    ' The authentication key (API Key).
    ' Get your own by registering at https://app.pdf.co
    Const API_KEY As String = "***********************************"

    ' Direct URL of source PDF file.
    ' You can also upload your own file into PDF.co and use it as url. Check "Upload File" samples for code snippets: https://github.com/bytescout/pdf-co-api-samples/tree/master/File%20Upload/   
    Const SourceFileUrl As String = "https://bytescout-com.s3.amazonaws.com/files/demo-files/cloud-api/pdf-edit/sample.pdf"

    ' Comma-separated list of page indices (Or ranges) to process. Leave empty for all pages. Example '0,2-5,7-'.
    Const Pages As String = ""

    ' PDF document password. Leave empty for unprotected documents.
    Const Password As String = ""

    ' Destination PDF file name
    Const DestinationFile As String = ".\result.pdf"

    ' Image params
    Private Const X1 As Int32 = 400
    Private Const Y1 As Int32 = 20
    Private Const Width1 As Int32 = 119
    Private Const Height1 As Int32 = 32
    Private Const ImageUrl As String = "https://bytescout-com.s3.amazonaws.com/files/demo-files/cloud-api/pdf-edit/logo.png"

    Sub Main()

        ' Create standard .NET web client instance
        Dim webClient As WebClient = New WebClient()

        ' Set API Key
        webClient.Headers.Add("x-api-key", API_KEY)

        ' Set JSON content type
        webClient.Headers.Add("Content-Type", "application/json")

        ' * Add image *
        ' Prepare URL for `PDF Edit` API call
		Dim url As String = "https://api.pdf.co/v1/pdf/edit/add"

        ' Prepare requests params as JSON
        ' See documentation: https://apidocs.pdf.co/04-pdf-add-text-signatures-and-images-to-pdf
        Dim jsonPayload As String = $"{{
    ""name"": ""{Path.GetFileName(DestinationFile)}"",
    ""url"": ""{SourceFileUrl}"",
    ""password"": ""{Password}"",
    ""images"": [
        {{
            ""url"": ""{ImageUrl}"",
            ""x"": {X1},
            ""y"": {Y1},
            ""width"": {Width1},
            ""height"": {Height1},
            ""pages"": ""{Pages}""
        }}
    ]
}}"

        Try
            ' Execute POST request with JSON payload
            Dim response As String = webClient.UploadString(url, jsonPayload)

            ' Parse JSON response
            Dim json As JObject = JObject.Parse(response)

            If json("error").ToObject(Of Boolean) = False Then

                ' Get URL of generated PDF file
                Dim resultFileUrl As String = json("url").ToString()

                ' Download PDF file
                webClient.DownloadFile(resultFileUrl, DestinationFile)

                Console.WriteLine("Generated PDF file saved as ""{0}"" file.", DestinationFile)

            Else
                Console.WriteLine(json("message").ToString())
            End If

        Catch ex As WebException
            Console.WriteLine(ex.ToString())
        End Try

        webClient.Dispose()

        Console.WriteLine()
        Console.WriteLine("Press any key...")
        Console.ReadKey()

    End Sub

End Module