using System;

using System.Text;
using COSXML.Utils;
using COSXML.CosException;
using COSXML.Common;
using COSXML.Log;
using COSXML.Network;
using System.IO;

namespace COSXML.Auth
{

    public abstract class QCloudCredentialProvider
    {
        public virtual QCloudCredentials GetQCloudCredentials()
        {
            return null;
        }

        public abstract void Refresh();

        public virtual QCloudCredentials GetQCloudCredentialsWithRequest(Request request)
        {
            return null;
        }

        public QCloudCredentials GetQCloudCredentialsCompat(Request request)
        {
            QCloudCredentials credentials = GetQCloudCredentialsWithRequest(request);

            if (credentials == null)
            {
                credentials = GetQCloudCredentials(); 
            }

            return credentials;
        }
    }

    /// <summary>
    /// 直接通过永久密钥初始化
    /// </summary>
    public class DefaultQCloudCredentialProvider : QCloudCredentialProvider
    {
        private string secretId;

        private string secretKey;

        private long keyTimDuration;

        public DefaultQCloudCredentialProvider(string secretId, string secretKey, long keyDurationSecond)
        {
            if (secretId == null || secretId.Length == 0)
                throw new CosClientException((int)CosClientError.InvalidArgument, "secretId is null or length is zero");
            if (secretKey == null || secretKey.Length == 0)
                throw new CosClientException((int)CosClientError.InvalidArgument, "secretKey is null or length is zero");
            this.secretId = secretId.Trim();
            this.secretKey = secretKey.Trim();
            this.keyTimDuration = keyDurationSecond;
        }

        public override QCloudCredentials GetQCloudCredentials()
        {
            long keyStartTime = TimeUtils_QCloud.GetCurrentTime(TimeUnit.Seconds);

            long keyEndTime = keyStartTime + keyTimDuration;

            string keyTime = String.Format("{0};{1}", keyStartTime, keyEndTime);

            if (secretId == null)
            {
                throw new CosClientException((int)CosClientError.InvalidCredentials, "secretId == null");
            }

            if (secretKey == null)
            {
                throw new CosClientException((int)CosClientError.InvalidCredentials, "secretKey == null");
            }

            string signKey = DigestUtils.GetHamcSha1ToHexString(keyTime, Encoding.UTF8, secretKey, Encoding.UTF8);

            return new QCloudCredentials(secretId, signKey, keyTime);
        }

        public override void Refresh()
        {
            //TODO update value
            QLog.Debug("DefaultQCloudCredentialProvider", "need to update QCloudCredentials");
            //invoke SetSetQCloudCredential(string secretId, string secretKey, string keyTime)
        }
    }

    /// <summary>
    /// 通过腾讯云临时密钥初始化
    /// </summary>
    public class DefaultSessionQCloudCredentialProvider : QCloudCredentialProvider
    {
        private string tmpSecretId;

        private string tmpSecretKey;

        private string keyTime;

        private string token;

        public DefaultSessionQCloudCredentialProvider(string tmpSecretId, string tmpSecretKey, long tmpExpiredTime, string sessionToken)
            : this(tmpSecretId, tmpSecretKey, TimeUtils_QCloud.GetCurrentTime(TimeUnit.Seconds), tmpExpiredTime, sessionToken)
        {
        }

        public DefaultSessionQCloudCredentialProvider(string tmpSecretId, string tmpSecretKey, long keyStartTimeSecond, long tmpExpiredTime, string sessionToken)
        {
            this.tmpSecretId = tmpSecretId;
            this.tmpSecretKey = tmpSecretKey;
            this.keyTime = String.Format("{0};{1}", keyStartTimeSecond, tmpExpiredTime);
            this.token = sessionToken;
        }

        public override QCloudCredentials GetQCloudCredentials()
        {

            if (IsNeedUpdateNow())
            {
                Refresh();
            }

            if (tmpSecretId == null)
            {
                throw new CosClientException((int)CosClientError.InvalidCredentials, "secretId == null");
            }

            if (tmpSecretKey == null)
            {
                throw new CosClientException((int)CosClientError.InvalidCredentials, "secretKey == null");
            }

            if (keyTime == null)
            {
                throw new CosClientException((int)CosClientError.InvalidCredentials, "keyTime == null");
            }

            string signKey = DigestUtils.GetHamcSha1ToHexString(keyTime, Encoding.UTF8, tmpSecretKey, Encoding.UTF8);

            return new SessionQCloudCredentials(tmpSecretId, signKey, token, keyTime);
        }

        public override void Refresh()
        {
            //TODO update value
            QLog.Debug("DefaultSessionQCloudCredentialProvider", "need to update QCloudCredentials");
            //invoke SetQCloudCredential(string tmpSecretId, string tmpSecretKey, string tmpkeyTime, string sessionToken)
        }

        public bool IsNeedUpdateNow()
        {

            if (String.IsNullOrEmpty(keyTime) || String.IsNullOrEmpty(tmpSecretId) || String.IsNullOrEmpty(tmpSecretKey) || String.IsNullOrEmpty(token))
            {

                return true;
            }

            int index = keyTime.IndexOf(';');
            long endTime = -1L;

            long.TryParse(keyTime.Substring(index + 1), out endTime);
            long nowTime = TimeUtils_QCloud.GetCurrentTime(TimeUnit.Seconds);

            if (endTime <= nowTime)
            {

                return true;
            }

            return false;
        }

        /// <summary>
        /// 直接设置临时密钥信息
        /// </summary>
        /// <param name="tmpSecretId">临时安全证书 Id</param>
        /// <param name="tmpSecretKey">临时安全证书 Key</param>
        /// <param name="tmpkeyTime">证书有效的期间</param>
        /// <param name="sessionToken">token 值</param>
        public void SetQCloudCredential(string tmpSecretId, string tmpSecretKey, string tmpkeyTime, string sessionToken)
        {
            this.tmpSecretId = tmpSecretId;
            this.tmpSecretKey = tmpSecretKey;
            this.token = sessionToken;
            this.keyTime = tmpkeyTime;
        }
    }


}