using System;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using Flurl.Util;

namespace Flurl.Http
{
	public static class ClientConfigExtensions
	{
		/// <summary>
		/// Fluently specify that an existing FlurlClient should be used to call the Url, rather than creating a new one.
		/// Enables re-using the underlying HttpClient.
		/// </summary>
		/// <param name="fc">The FlurlClient to use in calling the Url</param>
		/// <returns></returns>
		public static FlurlClient WithClient(this Url url, FlurlClient fc) {
			fc.Url = url;
			return fc;
		}

		/// <summary>
		/// Fluently specify that an existing FlurlClient should be used to call the Url, rather than creating a new one.
		/// Enables re-using the underlying HttpClient.
		/// </summary>
		/// <param name="fc">The FlurlClient to use in calling the Url</param>
		/// <returns></returns>
		public static FlurlClient WithClient(this string url, FlurlClient fc) {
			return new Url(url).WithClient(fc);
		}

		/// <summary>
		/// Fluently specify the URL to be called with the current FlurlClient instance.
		/// </summary>
		/// <param name="url">The Url to call.</param>
		/// <returns></returns>
		public static FlurlClient WithUrl(this FlurlClient client, Url url) {
			client.Url = url;
			return client;
		}

		/// <summary>
		/// Provides access to modifying the underlying HttpClient.
		/// </summary>
		/// <param name="action">Action to perform on the HttpClient.</param>
		/// <returns>The FlurlClient with the modified HttpClient</returns>
		public static FlurlClient ConfigureHttpClient(this FlurlClient client, Action<HttpClient> action) {
			action(client.HttpClient);
			return client;
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and provides access to modifying the underlying HttpClient.
		/// </summary>
		/// <param name="action">Action to perform on the HttpClient.</param>
		/// <returns>The FlurlClient with the modified HttpClient</returns>
		public static FlurlClient ConfigureHttpClient(this string url, Action<HttpClient> action) {
			return new FlurlClient(url, true).ConfigureHttpClient(action);
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and provides access to modifying the underlying HttpClient.
		/// </summary>
		/// <param name="action">Action to perform on the HttpClient.</param>
		/// <returns>The FlurlClient with the modified HttpClient</returns>
		public static FlurlClient ConfigureHttpClient(this Url url, Action<HttpClient> action) {
			return new FlurlClient(url, true).ConfigureHttpClient(action);
		}

		/// <summary>
		/// Sets the client timout to the specified timespan.
		/// </summary>
		/// <param name="timespan">Time to wait before the request times out.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithTimeout(this FlurlClient client, TimeSpan timespan) {
			client.HttpClient.Timeout = timespan;
			return client;
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets the client timout to the specified timespan.
		/// </summary>
		/// <param name="timespan">Time to wait before the request times out.</param>
		/// <returns>The created FlurlClient.</returns>
		public static FlurlClient WithTimeout(this string url, TimeSpan timespan) {
			return new FlurlClient(url, true).WithTimeout(timespan);
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets the client timout to the specified timespan.
		/// </summary>
		/// <param name="timespan">Time to wait before the request times out.</param>
		/// <returns>The created FlurlClient.</returns>
		public static FlurlClient WithTimeout(this Url url, TimeSpan timespan) {
			return new FlurlClient(url, true).WithTimeout(timespan);
		}

		/// <summary>
		/// Sets the client timout to the specified number of seconds.
		/// </summary>
		/// <param name="seconds">Number of seconds to wait before the request times out.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithTimeout(this FlurlClient client, int seconds) {
			return client.WithTimeout(TimeSpan.FromSeconds(seconds));
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets the client timout to the specified number of seconds.
		/// </summary>
		/// <param name="seconds">Number of seconds to wait before the request times out.</param>
		/// <returns>The created FlurlClient.</returns>
		public static FlurlClient WithTimeout(this string url, int seconds) {
			return new FlurlClient(url, true).WithTimeout(seconds);
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets the client timout to the specified number of seconds.
		/// </summary>
		/// <param name="seconds">Number of seconds to wait before the request times out.</param>
		/// <returns>The created FlurlClient.</returns>
		public static FlurlClient WithTimeout(this Url url, int seconds) {
			return new FlurlClient(url, true).WithTimeout(seconds);
		}

		/// <summary>
		/// Sets an HTTP header to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="name">HTTP header name.</param>
		/// <param name="value">HTTP header value.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithHeader(this FlurlClient client, string name, object value) {
			var values = new[] { (value == null) ? null : value.ToString() };
			client.HttpClient.DefaultRequestHeaders.Add(name, values);
			return client;
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets an HTTP header to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="name">HTTP header name.</param>
		/// <param name="value">HTTP header value.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithHeader(this string url, string name, object value) {
			return new FlurlClient(url, true).WithHeader(name, value);
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets an HTTP header to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="name">HTTP header name.</param>
		/// <param name="value">HTTP header value.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithHeader(this Url url, string name, object value) {
			return new FlurlClient(url, true).WithHeader(name, value);
		}

		/// <summary>
		/// Sets HTTP headers based on property names/values of the provided object, or keys/values if object is a dictionary, to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="headers">Names/values of HTTP headers to set. Typically an anonymous object or IDictionary.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithHeaders(this FlurlClient client, object headers) {
			if (headers == null)
				return client;

			foreach (var kv in headers.ToKeyValuePairs()) {
				if (kv.Value == null)
					continue;

				client.HttpClient.DefaultRequestHeaders.Add(kv.Key, new[] { kv.Value.ToString() });
			}

			return client;
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets HTTP headers based on property names/values of the provided object, or keys/values if object is a dictionary, to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="headers">Names/values of HTTP headers to set. Typically an anonymous object or IDictionary.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithHeaders(this Url url, object headers) {
			return new FlurlClient(url, true).WithHeaders(headers);
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets HTTP headers based on property names/values of the provided object, or keys/values if object is a dictionary, to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="headers">Names/values of HTTP headers to set. Typically an anonymous object or IDictionary.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithHeaders(this string url, object headers) {
			return new FlurlClient(url, true).WithHeaders(headers);
		}

		/// <summary>
		/// Sets HTTP authorization header according to Basic Authentication protocol to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="username">Username of authenticating user.</param>
		/// <param name="password">Password of authenticating user.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithBasicAuth(this FlurlClient client, string username, string password) {
			// http://stackoverflow.com/questions/14627399/setting-authorization-header-of-httpclient
			var value = Convert.ToBase64String(Encoding.UTF8.GetBytes(string.Format("{0}:{1}", username, password)));
			client.HttpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", value);
			return client;
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets HTTP authorization header according to Basic Authentication protocol to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="username">Username of authenticating user.</param>
		/// <param name="password">Password of authenticating user.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithBasicAuth(this Url url, string username, string password) {
			return new FlurlClient(url, true).WithBasicAuth(username, password);
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets HTTP authorization header according to Basic Authentication protocol to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="username">Username of authenticating user.</param>
		/// <param name="password">Password of authenticating user.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithBasicAuth(this string url, string username, string password) {
			return new FlurlClient(url, true).WithBasicAuth(username, password);
		}

		/// <summary>
		/// Sets HTTP authorization header with acquired bearer token according to OAuth 2.0 specification to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="token">The acquired bearer token to pass.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithOAuthBearerToken(this FlurlClient client, string token) {
			client.HttpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
			return client;
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets HTTP authorization header with acquired bearer token according to OAuth 2.0 specification to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="token">The acquired bearer token to pass.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithOAuthBearerToken(this Url url, string token) {
			return new FlurlClient(url, true).WithOAuthBearerToken(token);
		}

		/// <summary>
		/// Creates a FlurlClient from the URL and sets HTTP authorization header with acquired bearer token according to OAuth 2.0 specification to be sent with all requests made with this FlurlClient.
		/// </summary>
		/// <param name="token">The acquired bearer token to pass.</param>
		/// <returns>The modified FlurlClient.</returns>
		public static FlurlClient WithOAuthBearerToken(this string url, string token) {
			return new FlurlClient(url, true).WithOAuthBearerToken(token);
		}
	}
}