PDFEngineAPI/BlackRock.Reporting.API/Persistence/PdfGenerator.cs

using BlackRock.Reporting.API.Core.Interfaces;
using iTextSharp.text;
using iTextSharp.text.pdf;
using PuppeteerSharp;

namespace BlackRock.Reporting.API.Persistence
{
    public class PdfGenerator : IPdfGenerator
    {
        private readonly IHostEnvironment host;
        public PdfGenerator(IHostEnvironment host)
        {
            this.host = host;
        }
        public async Task Generate(string url, string path, PdfOptions options)
        {
            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);
            var opts = new LaunchOptions
            {
                Headless = true
            };
            using (var browser = await Puppeteer.LaunchAsync(opts))
            using (var page = await browser.NewPageAsync())
            {
                await page.GoToAsync(url, WaitUntilNavigation.DOMContentLoaded);


                var allResultsSelector = ".chartjs-render-monitor";
                await page.WaitForSelectorAsync(allResultsSelector);
                await EvaluateScript(page, "dist/main.js");

                await page.PdfAsync(path, options);

                var pixels = CalculatePixels(options.MarginOptions.Top);
                ModifyPDF(path, pixels);
            }
        }
        public async Task Isolate(string url, string path, PdfOptions options)
        {
            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);
            var opts = new LaunchOptions
            {
                Headless = true
            };
            using (var browser = await Puppeteer.LaunchAsync(opts))
            using (var page = await browser.NewPageAsync())
            {
                await page.GoToAsync(url, WaitUntilNavigation.DOMContentLoaded);


                var allResultsSelector = ".chartjs-render-monitor";
                await page.WaitForSelectorAsync(allResultsSelector);

                await page.EvaluateFunctionAsync("() => document.getElementById('sel').selectedIndex = " + ((options.Landscape) ? 1 : 0));
                await page.ClickAsync("button.dugme");
                await EvaluateScript(page, "dist/main.js");
                await EvaluateScript(page, "dist/main2.js");
                await page.PdfAsync(path, options);
            }
        }
        private async Task EvaluateScript(Page page, string fileName)
        {
            string path2 = Path.Combine(host.ContentRootPath, fileName);
            var result = await System.IO.File.ReadAllTextAsync(path2);
            await page.EvaluateExpressionAsync(result);
        }
        private void ModifyPDF(string path, double marginTop)
        {
            var filePath = path;
            byte[] bytes = System.IO.File.ReadAllBytes(filePath);
            var pdfReader = new PdfReader(bytes);
            using (Stream output = new FileStream(filePath, FileMode.Create, FileAccess.Write, FileShare.None))
            {
                using (PdfStamper pdfStamper = new PdfStamper(pdfReader, output))
                {
                    for (int pageIndex = 1; pageIndex <= pdfReader.NumberOfPages; pageIndex++)
                    {
                        pdfStamper.FormFlattening = false;
                        Rectangle pageRectangle = pdfReader.GetPageSizeWithRotation(pageIndex);
                        PdfContentByte pdfData = pdfStamper.GetOverContent(pageIndex);
                        pdfData.SetFontAndSize(BaseFont.CreateFont(BaseFont.HELVETICA_BOLD, BaseFont.CP1252, BaseFont.NOT_EMBEDDED), 10);
                        PdfGState graphicsState = new PdfGState
                        {
                            FillOpacity = 0.3F
                        };
                        pdfData.SetGState(graphicsState);
                        Image image = Image.GetInstance(Path.Combine(host.ContentRootPath, "logo.png"));
                        var OriginalWidth = image.Width;
                        var OriginialHeight = image.Height;
                        var scale = OriginalWidth / OriginialHeight;
                        OriginialHeight = (float)marginTop - 5;
                        OriginalWidth = OriginialHeight * scale;
                        image.ScaleAbsoluteWidth(OriginalWidth);
                        image.ScaleAbsoluteHeight(OriginialHeight);
                        image.SetAbsolutePosition(5, pageRectangle.Height - OriginialHeight - 5);
                        pdfData.AddImage(image);
                    }
                }
                output.Close();
                output.Dispose();
            }
        }

        private double CalculatePixels(string v)
        {
            float Result;
            if (float.TryParse(v, out Result))
                return 2.83 * Result;
            var num = float.Parse(v.Split(' ')[0]);
            return 2.83 * num;
        }
    }
}