var https = require("https");
var path = require("path");
var fs = require("fs");

// Visit Knowledgebase for adding Text Macros to PDF 
// https://apidocs.pdf.co/kb/Fill%20PDF%20and%20Add%20Text%20or%20Images%20(pdf-edit-add)/macros

// The authentication key (API Key).
// Get your own by registering at https://app.pdf.co
const 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 SourceFileUrl = "https://bytescout-com.s3-us-west-2.amazonaws.com/files/demo-files/cloud-api/pdf-edit/10pages.pdf";

// Output File
const DestinationFile = "./result.pdf";

// PDF document password. Leave empty for unprotected documents.
const Password = "";

// * Add image *
// Prepare request to `PDF Edit` API endpoint
var queryPath = `/v1/pdf/edit/add`;

// JSON payload for api request
var jsonPayload = JSON.stringify({
    name: path.basename(DestinationFile),
    password: Password,
    url: SourceFileUrl,
    annotations: [
        {
            "text": "Page {{$$PageNumber}} of {{$$PageCount}}",
            "x": 500,
            "y": 10,
            "size": 12,
            "pages": "0-"
        }
    ]
});

var reqOptions = {
    host: "api.pdf.co",
    method: "POST",
    path: queryPath,
    headers: {
        "x-api-key": API_KEY,
        "Content-Type": "application/json",
        "Content-Length": Buffer.byteLength(jsonPayload, 'utf8')
    }
};
// Send request
var postRequest = https.request(reqOptions, (response) => {
    response.on("data", (d) => {
        // Parse JSON response
        var data = JSON.parse(d);

        if (data.error == false) {
            // Download the PDF file
            var file = fs.createWriteStream(DestinationFile);
            https.get(data.url, (response2) => {
                response2.pipe(file).on("close", () => {
                    console.log(`Generated PDF file saved to '${DestinationFile}' file.`);
                });
            });
        }
        else {
            // Service reported error
            console.log(data.message);
        }
    });
}).on("error", (e) => {
    // Request error
    console.error(e);
});

// Write request data
postRequest.write(jsonPayload);
postRequest.end();