using Aspose.Pdf;
using Aspose.Pdf.Devices;
using System.Collections;
using System.Collections.Generic;
using System.Drawing;
using System.IO;
using UnityEngine;

/// <summary>
/// PDF转图片
/// </summary>
public class LoadPDFTest : MonoBehaviour
{
    public static LoadPDFTest Instance;

    public GameObject imageprefab;
    public Transform content;

    private void Start()
    {
        Instance = this;
    }
    /// <summary>
    /// 加载PDF
    /// </summary>
    public void LoadPDFGo(string path)
    {
        //清理content下的旧物体
        for (int i = 0; i < content.childCount; i++)
        {
            Destroy(content.GetChild(i).gameObject);
        }

        Document pdf = new Document(path);


        for (int i = 1; i <= pdf.Pages.Count; i++)
        {
            //PngDevice pngDevice = new PngDevice((int)pdf.Pages[i].PageInfo.Width,(int)pdf.Pages[i].PageInfo.Height);
            PngDevice pngDevice = new PngDevice((int)pdf.Pages[i].PageInfo.Width*2,(int)pdf.Pages[i].PageInfo.Height*2);

            //声明内存流，将图片转换为内存流，再由流转换为byte数组，然后用texture2d加载byte数组
            using (MemoryStream ms = new MemoryStream())
            {
                pngDevice.Process(pdf.Pages[i], ms);
                byte[] buff = new byte[ms.Length];
                ms.Seek(0, SeekOrigin.Begin);
                ms.Read(buff, 0, (int)ms.Length);

                //注意这个iamge的命名空间为system.drawing不是unity.ui,这个图片的目的是提供图片的宽高
                System.Drawing.Image sizeImage = System.Drawing.Image.FromStream(ms);

                Texture2D texture2D = new Texture2D(sizeImage.Width, sizeImage.Height);
                texture2D.LoadImage(buff);

                UnityEngine.UI.Image image = Instantiate(imageprefab, content).GetComponent<UnityEngine.UI.Image>();
                //根据转化出来的图片的大小设置unity image的大小
                image.rectTransform.sizeDelta = new Vector2(sizeImage.Width, sizeImage.Height);
                //用texture2d为精灵赋值
                image.sprite = Sprite.Create(texture2D, new Rect(0, 0, texture2D.width, texture2D.height), Vector2.zero);
            }

        }

    }

}