using System.Collections.Specialized;
using System.Net;
using System.Text;

namespace JNPF.Extras.CollectiveOAuth.Utils;

public class HttpUtils
{
    /// <summary>
    /// 模拟Form表单post请求.
    /// </summary>
    /// <param name="postUrl"></param>
    /// <param name="postData"></param>
    /// <param name="header"></param>
    /// <param name="charset"></param>
    /// <returns></returns>
    public static string RequestFormPost(string postUrl, string postData = null, Dictionary<string, object> header = null, string charset = null)
    {
        System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12; // 加上这一句
        if (string.IsNullOrWhiteSpace(charset))
            charset = "UTF-8";

        if (string.IsNullOrWhiteSpace(postData))
            postData = string.Empty;

        Stream outstream = null;
        Stream instream = null;
        StreamReader sr = null;
        HttpWebResponse response = null;
        HttpWebRequest request = null;
        Encoding encoding = System.Text.Encoding.GetEncoding(charset);

        byte[] data = encoding.GetBytes(postData);

        // 准备请求...
        try
        {
            // 设置参数
            request = WebRequest.Create(postUrl) as HttpWebRequest;
            CookieContainer cookieContainer = new CookieContainer();
            request.CookieContainer = cookieContainer;
            request.AllowAutoRedirect = true;
            request.Method = "POST";
            request.ContentType = "application/x-www-form-urlencoded;charset=" + charset.ToLower();
            request.ContentLength = data.Length;

            ComeSetRequestHeader(request, header);

            outstream = request.GetRequestStream();
            outstream.Write(data, 0, data.Length);
            outstream.Close();

            // 发送请求并获取相应回应数据
            response = request.GetResponse() as HttpWebResponse;

            // 直到request.GetResponse()程序才开始向目标网页发送Post请求
            instream = response.GetResponseStream();
            sr = new StreamReader(instream, encoding);

            // 返回结果网页（html）代码
            string content = sr.ReadToEnd();
            string err = string.Empty;
            return content;
        }
        catch (Exception ex)
        {
            string err = ex.Message;
            return string.Empty;
        }
    }

    /// <summary>
    /// 普通post请求.
    /// </summary>
    /// <param name="postUrl"></param>
    /// <param name="postData"></param>
    /// <param name="header"></param>
    /// <param name="charset"></param>
    /// <returns></returns>
    public static string RequestPost(string postUrl, string postData = null, Dictionary<string, object> header = null, string charset = null)
    {
        System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12; // 加上这一句
        if (string.IsNullOrWhiteSpace(charset))
        {
            charset = "UTF-8";
        }

        if (string.IsNullOrWhiteSpace(postData))
        {
            postData = string.Empty;
        }

        Stream outstream = null;
        Stream instream = null;
        StreamReader sr = null;
        HttpWebResponse response = null;
        HttpWebRequest request = null;
        Encoding encoding = System.Text.Encoding.GetEncoding(charset);

        byte[] data = encoding.GetBytes(postData);

        // 准备请求...
        try
        {
            // 设置参数
            request = WebRequest.Create(postUrl) as HttpWebRequest;
            CookieContainer cookieContainer = new CookieContainer();
            request.CookieContainer = cookieContainer;
            request.AllowAutoRedirect = true;
            request.Method = "POST";
            request.ContentType = "application/json;charset=" + charset.ToLower();
            request.ContentLength = data.Length;

            ComeSetRequestHeader(request, header);

            outstream = request.GetRequestStream();
            outstream.Write(data, 0, data.Length);
            outstream.Close();
            // 发送请求并获取相应回应数据
            response = request.GetResponse() as HttpWebResponse;
            // 直到request.GetResponse()程序才开始向目标网页发送Post请求
            instream = response.GetResponseStream();
            sr = new StreamReader(instream, encoding);
            // 返回结果网页（html）代码
            string content = sr.ReadToEnd();
            string err = string.Empty;
            return content;
        }
        catch (Exception ex)
        {
            string err = ex.Message;
            return string.Empty;
        }
    }

    /// <summary>
    /// 有一些请求比较特殊，需要标记Accept为application/json.
    /// </summary>
    /// <param name="url">地址.</param>
    /// <returns></returns>
    public static string RequestJsonGet(string url, Dictionary<string, object> header = null)
    {
        StringBuilder builder = new StringBuilder();
        builder.Append(url);
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(builder.ToString());
        request.UserAgent = "Foo";
        request.Accept = "application/json";
        ComeSetRequestHeader(request, header);
        return ComeRequestGet(request);
    }

    /// <summary>
    /// 发送Get请求.
    /// </summary>
    /// <param name="url">地址.</param>
    /// <param name="header">请求参数定义.</param>
    public static string RequestGet(string url, Dictionary<string, object> header = null)
    {
        StringBuilder builder = new StringBuilder();
        builder.Append(url);
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(builder.ToString());
        request.ContentType = "application/json;charset=utf-8;";
        ComeSetRequestHeader(request, header);
        return ComeRequestGet(request);
    }

    /// <summary>
    /// 通用的设置RequestHeader方法.
    /// </summary>
    /// <param name="request"></param>
    /// <param name="header"></param>
    public static void ComeSetRequestHeader(HttpWebRequest request, Dictionary<string, object> header = null)
    {
        if (header != null && header.Count > 0)
        {
            foreach (var item in header)
            {
                switch (item.Key.ToUpper())
                {
                    case "HOST":
                        request.Host = Convert.ToString(item.Value);
                        break;
                    case "CONTENT-TYPE":
                        request.ContentType = Convert.ToString(item.Value);
                        break;
                    case "CONNECTION":
                        SetSpecialHeaderValue(request.Headers, item.Key, Convert.ToString(item.Value));
                        break;
                    default:
                        request.Headers.Add(item.Key, Convert.ToString(item.Value));
                        break;
                }
            }
        }
    }

    /// <summary>
    /// 设置特殊的header.
    /// </summary>
    /// <param name="header"></param>
    /// <param name="name"></param>
    /// <param name="value"></param>
    public static void SetSpecialHeaderValue(WebHeaderCollection header, string name, string value)
    {
        var property = typeof(WebHeaderCollection).GetProperty("InnerCollection",
            System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic);
        if (property != null)
        {
            var collection = property.GetValue(header, null) as NameValueCollection;
            collection[name] = value;
        }
    }

    /// <summary>
    /// 通用的get请求.
    /// </summary>
    /// <param name="request"></param>
    /// <returns></returns>
    public static string ComeRequestGet(HttpWebRequest request)
    {
        string result = "";
        request.AllowAutoRedirect = true;
        request.Method = "GET";
        request.CookieContainer = new CookieContainer();
        request.Credentials = CredentialCache.DefaultCredentials;
        HttpWebResponse resp = (HttpWebResponse)request.GetResponse();
        Stream stream = resp.GetResponseStream();
        try
        {
            // 获取内容
            using (StreamReader reader = new StreamReader(stream))
            {
                result = reader.ReadToEnd();
            }
        }
        finally
        {
            stream.Close();
        }
        return result;
    }

    /// <summary>
    /// 通用的Post请求.
    /// </summary>
    /// <param name="request"></param>
    /// <returns></returns>
    public static string ComeRequestPost(HttpWebRequest request)
    {
        string result = "";
        request.AllowAutoRedirect = true;
        request.Method = "POST";
        request.CookieContainer = new CookieContainer();
        request.Credentials = CredentialCache.DefaultCredentials;
        HttpWebResponse resp = (HttpWebResponse)request.GetResponse();
        Stream stream = resp.GetResponseStream();
        try
        {
            // 获取内容
            using (StreamReader reader = new StreamReader(stream))
            {
                result = reader.ReadToEnd();
            }
        }
        finally
        {
            stream.Close();
        }
        return result;
    }

}