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YandexMusic.API/Requests/Account/YGetAuthCookiesBuilder.cs

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+using System.Net;
+using System.Net.Http.Headers;
+
+using YandexMusic.API.Common;
+using YandexMusic.API.Models.Account;
+using YandexMusic.API.Requests.Common;
+using YandexMusic.API.Requests.Common.Attributes;
+
+namespace YandexMusic.API.Requests.Account
+{
+    [YMobileProxyRequest(WebRequestMethods.Http.Post, "1/bundle/oauth/token_by_sessionid")]
+    internal class YGetAuthCookiesBuilder : YRequestBuilder<YAccessToken, string>
+    {
+        public YGetAuthCookiesBuilder(YandexMusicApi yandex, AuthStorage auth) : base(yandex, auth)
+        {
+        }
+
+        protected override void SetCustomHeaders(HttpRequestHeaders headers)
+        {
+            CookieCollection cookieCollection = new() {
+                storage.Context.Cookies.GetCookies(new Uri("https://yandex.ru/")),
+                storage.Context.Cookies.GetCookies(new Uri("https://passport.yandex.ru/"))
+            };
+
+            headers.Add("Ya-Client-Cookie", string.Join(";", cookieCollection.Select(c => $"{c.Name}={c.Value}")));
+            headers.Add("Ya-Client-Host", "passport.yandex.ru");
+        }
+
+        protected override HttpContent GetContent(string tuple)
+        {
+            return new FormUrlEncodedContent(new Dictionary<string, string> {
+                { "client_id", YConstants.XClientId },
+                { "client_secret", YConstants.XClientSecret }
+            });
+        }
+    }
+}