using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.Net;
using System.Runtime.InteropServices;
using System.Threading;

namespace ByteScoutWebApiExample
{
    class Program
    {
        // The authentication key (API Key).
        // Get your own by registering at https://app.pdf.co
        const String API_KEY = "*************************";

        // 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 string SourceFileUrl = "https://bytescout-com.s3-us-west-2.amazonaws.com/files/demo-files/cloud-api/pdf-form/f1040.pdf";
        // PDF document password. Leave empty for unprotected documents.
        const string Password = "";
        // File name for generated output. Must be a String
        const string FileName = "f1040-form-filled";

        // Destination File Name
        const string DestinationFile = "./result.pdf";

        static void Main(string[] args)
        {
            // Create standard .NET web client instance
            WebClient webClient = new WebClient();

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

            // Values to fill out pdf fields with built-in pdf form filler
            var fields = new List<object> {
                new { fieldName = "topmostSubform[0].Page1[0].FilingStatus[0].c1_01[1]", pages = "1", text = "True" },
                new { fieldName = "topmostSubform[0].Page1[0].f1_02[0]", pages = "1", text = "John A." },
                new { fieldName = "topmostSubform[0].Page1[0].f1_03[0]", pages = "1", text = "Doe" },
                new { fieldName = "topmostSubform[0].Page1[0].YourSocial_ReadOrderControl[0].f1_04[0]", pages = "1", text = "123456789" },
                new { fieldName = "topmostSubform[0].Page1[0].YourSocial_ReadOrderControl[0].f1_05[0]", pages = "1", text = "John  B." },
                new { fieldName = "topmostSubform[0].Page1[0].YourSocial_ReadOrderControl[0].f1_06[0]", pages = "1", text = "Doe" },
                new { fieldName = "topmostSubform[0].Page1[0].YourSocial_ReadOrderControl[0].f1_07[0]", pages = "1", text = "987654321" }
            };

            // If enabled, Runs processing asynchronously. Returns Use JobId that you may use with /job/check to check state of the processing (possible states: working, 
            var async = true; // (!) Make asynchronous job

            // Prepare requests params as JSON
            // See documentation: https://apidocs.pdf.co
            Dictionary<string, object> parameters = new Dictionary<string, object>();
            parameters.Add("url", SourceFileUrl);
            parameters.Add("name", FileName);
            parameters.Add("password", Password);
            parameters.Add("async", async);
            parameters.Add("fields", fields);

            // Convert dictionary of params to JSON
            string jsonPayload = JsonConvert.SerializeObject(parameters);

            try
            {
                // URL of "PDF Edit" endpoint
                string url = "https://api.pdf.co/v1/pdf/edit/add";

                // Execute POST request with JSON payload
                string response = webClient.UploadString(url, jsonPayload);

                // Parse JSON response
                JObject json = JObject.Parse(response);

                if (json["error"].ToObject<bool>() == false)
                {
                    // Asynchronous job ID
                    string jobId = json["jobId"].ToString();
                    // URL of generated PDF file that will available after the job completion
                    string resultFileUrl = json["url"].ToString();

                    // Check the job status in a loop. 
                    // If you don't want to pause the main thread you can rework the code 
                    // to use a separate thread for the status checking and completion.
                    do
                    {
                        string status = CheckJobStatus(jobId); // Possible statuses: "working", "failed", "aborted", "success".

                        // Display timestamp and status (for demo purposes)
                        Console.WriteLine(DateTime.Now.ToLongTimeString() + ": " + status);

                        if (status == "success")
                        {
                            // Download PDF file
                            webClient.DownloadFile(resultFileUrl, DestinationFile);

                            Console.WriteLine("Generated PDF file saved as \"{0}\" file.", DestinationFile);
                            break;
                        }
                        else if (status == "working")
                        {
                            // Pause for a few seconds
                            Thread.Sleep(3000);
                        }
                        else
                        {
                            Console.WriteLine(status);
                            break;
                        }
                    }
                    while (true);
                }
                else
                {
                    Console.WriteLine(json["message"].ToString());
                }
            }
            catch (WebException e)
            {
                Console.WriteLine(e.ToString());
            }
            finally
            {
                webClient.Dispose();
            }

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

        /// <summary>
        /// Check job status
        /// </summary>
        static string CheckJobStatus(string jobId)
        {
            using (WebClient webClient = new WebClient())
            {
                // Set API Key
                webClient.Headers.Add("x-api-key", API_KEY);

                string url = "https://api.pdf.co/v1/job/check?jobid=" + jobId;

                string response = webClient.DownloadString(url);
                JObject json = JObject.Parse(response);

                return Convert.ToString(json["status"]);
            }
        }

    }
}