Imports System.IO
Imports System.Net
Imports Newtonsoft.Json
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 file to search barcodes in.
    ' 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/barcode-reader/sample.pdf"
    ' Comma-separated list of barcode types to search. 
    ' See valid barcode types in the documentation https://apidocs.pdf.co
    Const Pages As String = ""

    ' Some of advanced options available through profiles:
    ' (JSON can be single/double-quoted and contain comments.)
    ' {
    '     "profiles": [
    '         {
    '             "profile1": {
    '                 "ScanArea": "WholePage", // Values: "TopLeftQuarter", "TopRightQuarter", "BottomRightQuarter", "BottomLeftQuarter", "TopHalf", "BottomHalf", "WholePage".
    '                 "RequireQuietZones": true, // Whether the quite zone is obligatory for 1D barcodes. Values: true / false
    '                 "MaxNumberOfBarcodesPerPage": 0, // 0 - unlimited.
    '                 "MaxNumberOfBarcodesPerDocument": 0, // 0 - unlimited.
    '                 "ScanStep": 1, // Scan interval for linear (1-dimensional) barcodes.
    '                 "MinimalDataLength": 0, // Minimal acceptable length of decoded data.                
    '             }
    '         }
    '     ]
    ' }

    ' Sample profile that sets advanced conversion options
    ' Advanced options are properties of Reader class from Bytescout BarCodeReader used in the back-end:
    ' https//cdn.bytescout.com/help/BytescoutBarCodeReaderSDK/html/ba101d21-3db7-eb54-d112-39cadc023d02.htm
    ReadOnly Profiles = File.ReadAllText("profile.json")

    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")

        ' Prepare URL for `Barcode Reader` API call
        Dim url As String = "https://api.pdf.co/v1/barcode/read/from/url"

        ' Prepare requests params as JSON
        ' See documentation: https : //apidocs.pdf.co
        Dim parameters As New Dictionary(Of String, Object)
        parameters.Add("pages", Pages)
        parameters.Add("url", SourceFileURL)
        parameters.Add("profiles", Profiles)

        ' Convert dictionary of params to JSON
        Dim jsonPayload As String = JsonConvert.SerializeObject(parameters)

        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

                ' Display found barcodes in console
                For Each token As JToken In json("barcodes")
                    Console.WriteLine("Found barcode:")
                    Console.WriteLine("  Type: " + token("TypeName").ToString())
                    Console.WriteLine("  Value: " + token("Value").ToString())
                    Console.WriteLine("  Document Page Index: " + token("Page").ToString())
                    Console.WriteLine("  Rectangle: " + token("Rect").ToString())
                    Console.WriteLine("  Confidence: " + token("Confidence").ToString())
                    Console.WriteLine()
                Next

            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