using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Threading;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

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

        // Source PDF file to split
        const string SourceFile = @".\sample.pdf";
        // Comma-separated list of page numbers (or ranges) to process. Example: '1,3-5,7-'.
        const string Pages = "1-2,3-";
        // (!) Make asynchronous job
        const bool Async = true;


        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);

            // 1. RETRIEVE THE PRESIGNED URL TO UPLOAD THE FILE.
            // * If you already have a direct file URL, skip to the step 3.

            // Prepare URL for `Get Presigned URL` API call
            string query = Uri.EscapeUriString(string.Format(
                "https://api.pdf.co/v1/file/upload/get-presigned-url?contenttype=application/octet-stream&name={0}", 
                Path.GetFileName(SourceFile)));

            try
            {
                // Execute request
                string response = webClient.DownloadString(query);

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

                if (json["error"].ToObject<bool>() == false)
                {
                    // Get URL to use for the file upload
                    string uploadUrl = json["presignedUrl"].ToString();
                    string uploadedFileUrl = json["url"].ToString();

                    // 2. UPLOAD THE FILE TO CLOUD.

                    webClient.Headers.Add("content-type", "application/octet-stream");
                    webClient.UploadFile(uploadUrl, "PUT", SourceFile); // You can use UploadData() instead if your file is byte[] or Stream
                    webClient.Headers.Remove("content-type");

                    // 3. SPLIT UPLOADED PDF

                    // URL for `Split PDF` API call
                    var url = "https://api.pdf.co/v1/pdf/split";

                    // Prepare requests params as JSON
                    Dictionary<string, object> parameters = new Dictionary<string, object>();
                    parameters.Add("pages", Pages);
                    parameters.Add("url", uploadedFileUrl);
                    parameters.Add("async", Async);

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

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

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

                    if (json["error"].ToObject<bool>() == false)
                    {
                        // Asynchronous job ID
                        string jobId = json["jobId"].ToString();
                        // URL of generated JSON file available after the job completion; it will contain URLs of result PDF files.
                        string resultJsonFileUrl = 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 JSON file as string
                                string jsonFileString = webClient.DownloadString(resultJsonFileUrl);

                                JArray resultFilesUrls = JArray.Parse(jsonFileString);

                                // Download generated PDF files
                                int part = 1;
                                foreach (JToken token in resultFilesUrls)
                                {
                                    string resultFileUrl = token.ToString();
                                    string localFileName = String.Format(@".\part{0}.pdf", part);

                                    webClient.DownloadFile(resultFileUrl, localFileName);

                                    Console.WriteLine("Downloaded \"{0}\".", localFileName);
                                    part++;
                                }
                                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());
                    }

                }
                else
                {
                    Console.WriteLine(json["message"].ToString());
                }
            }
            catch (WebException e)
            {
                Console.WriteLine(e.ToString());
            }

            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"]);
            }
        }

    }
}