using iTextSharp.text.pdf;
using iTextSharp.text;
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Net.Http;
using System.Net;

namespace 心电图绘制
{
    internal class UniversalFun
    {
        /// <summary>
        /// base64转换成图片
        /// </summary>
        /// <param name="base64String"></param>
        /// <returns></returns>
        public static System.Drawing.Image ConvertFromBase64String(string base64String)
        {
           string [] baseary= base64String.Split(',');
            if(baseary.Length<2)
            {
                return null;
            }
            // 将Base64字符串转换为字节数组
            byte[] imageBytes = Convert.FromBase64String(baseary[1]);

            // 使用字节数组创建MemoryStream
            using (MemoryStream ms = new MemoryStream(imageBytes))
            {
                // 从MemoryStream中创建Image对象
                System.Drawing.Image image = System.Drawing.Image.FromStream(ms);
                return image;
            }
        }
        /// <summary>
        /// 图片转换成base64
        /// </summary>
        /// <param name="bitmap"></param>
        /// <param name="format"></param>
        /// <returns></returns>
        public static string ConvertToBase64String(Bitmap bitmap, ImageFormat format)
        {
            // 将Bitmap保存到MemoryStream中
            using (MemoryStream ms = new MemoryStream())
            {
                bitmap.Save(ms, format); // 可以根据需要选择不同的图片格式，例如ImageFormat.Png或ImageFormat.Jpeg
                                         // 将流的位置重置到开始位置
                ms.Position = 0;
                // 将MemoryStream中的字节数组编码为Base64字符串
                byte[] imageBytes = ms.ToArray();
                string base64String = Convert.ToBase64String(imageBytes);
                return base64String;
            }
        }

        /// <summary>
        /// 图片转换成PDF
        /// </summary>
        /// <param name="bitmap"></param>
        /// <param name="pdfPath"></param>
        public static void ConvertBitmapToPdf(Bitmap bitmap, string pdfPath)
        {

            string directoryPath = Path.GetDirectoryName(pdfPath);
            if (directoryPath != null && !Directory.Exists(directoryPath))
            {
                Directory.CreateDirectory(directoryPath);
            }
            // 创建一个文档对象
            Document document = new Document();

            // 创建一个PdfWriter实例
            PdfWriter writer = PdfWriter.GetInstance(document, new FileStream(pdfPath, FileMode.Create));

            // 打开文档以便添加内容
            document.Open();
            // 设置页面尺寸与图像尺寸一致
            iTextSharp.text.Rectangle pageSize = new iTextSharp.text.Rectangle(bitmap.Width, bitmap.Height+50);
            document.SetPageSize(pageSize);
            // 将Bitmap转换为iTextSharp的Image对象
            iTextSharp.text.Image image = ConvertBitmapToImageSharp(bitmap);

            // 将图像添加到文档
            document.NewPage();
            document.Add(image);

            // 关闭文档
            document.Close();
        }

        private static iTextSharp.text.Image ConvertBitmapToImageSharp(Bitmap bitmap)
        {
            using (MemoryStream ms = new MemoryStream())
            {
                // 将Bitmap保存到MemoryStream中，使用PNG格式
                bitmap.Save(ms, ImageFormat.Png);

                // 从MemoryStream中创建iTextSharp的Image对象
                return iTextSharp.text.Image.GetInstance(new MemoryStream(ms.ToArray()));
            }
        }

        /// <summary>
        /// 获取指定 URL 的文本文件内容
        /// </summary>
        /// <param name="url">文本文件的 URL</param>
        /// <returns>返回文件内容的字符串，如果失败则返回 null</returns>
      public  static string GetTextFileContent(string url)
        {
            // 忽略 SSL 证书错误
            ServicePointManager.ServerCertificateValidationCallback = (sender, certificate, chain, sslPolicyErrors) => true;
            using (WebClient client = new WebClient())
            {
                try
                {
                    // 下载文件内容
                    return client.DownloadString(url);
                }
                catch (WebException e)
                {
                    Console.WriteLine("请求错误: " + e.Message);
                    return null;
                }
            }
        }
    }
}