/* vim: ts=4:sw=4
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

window.textsecure = window.textsecure || {};

window.textsecure.api = function() {
	var self = {};

	/************************************************
	 *** Utilities to communicate with the server ***
	 ************************************************/
	// Staging server
	var URL_BASE	= "https://textsecure-service-ca.whispersystems.org:4433";

	// This is the real server
	//var URL_BASE	= "https://textsecure-service.whispersystems.org";

	var URL_CALLS = {};
	URL_CALLS['accounts']	= "/v1/accounts";
	URL_CALLS['devices']	= "/v1/devices";
	URL_CALLS['keys']		= "/v2/keys";
	URL_CALLS['push']		= "/v1/websocket";
	URL_CALLS['messages']	= "/v1/messages";
	URL_CALLS['attachment']	= "/v1/attachments";

	/**
		* REQUIRED PARAMS:
		* 	call:				URL_CALLS entry
		* 	httpType:			POST/GET/PUT/etc
		* OPTIONAL PARAMS:
		* 	success_callback:	function(response object) called on success
		* 	error_callback: 	function(http status code = -1 or != 200) called on failure
		* 	urlParameters:		crap appended to the url (probably including a leading /)
		* 	user:				user name to be sent in a basic auth header
		* 	password:			password to be sent in a basic auth headerA
		* 	do_auth:			alternative to user/password where user/password are figured out automagically
		* 	jsonData:			JSON data sent in the request body
		*/
	var doAjax = function(param) {
		if (param.urlParameters === undefined)
			param.urlParameters = "";

		if (param.do_auth) {
			param.user		= textsecure.storage.getUnencrypted("number_id");
			param.password	= textsecure.storage.getEncrypted("password");
		}

		return new Promise(function(resolve, reject) {
			$.ajax(URL_BASE + URL_CALLS[param.call] + param.urlParameters, {
				type		: param.httpType,
				data		: param.jsonData && textsecure.utils.jsonThing(param.jsonData),
				contentType : 'application/json; charset=utf-8',
				dataType	: 'json',

				beforeSend	: function(xhr) {
								if (param.user		 !== undefined &&
									param.password !== undefined)
										xhr.setRequestHeader("Authorization", "Basic " + btoa(getString(param.user) + ":" + getString(param.password)));
								},

				success		: function(response, textStatus, jqXHR) {
									resolve(response);
								},

				error		: function(jqXHR, textStatus, errorThrown) {
									var code = jqXHR.status;
									if (code == 200) {
										// happens sometimes when we get no response
										// (TODO: Fix server to return 204? instead)
										resolve(null);
										return;
									}
									if (code > 999 || code < 100)
										code = -1;
									try {
										switch (code) {
										case -1:
											textsecure.throwHumanError(code, "HTTPError", "Failed to connect to the server, please check your network connection.");
										case 413:
											textsecure.throwHumanError(code, "HTTPError", "Rate limit exceeded, please try again later.");
										case 403:
											textsecure.throwHumanError(code, "HTTPError", "Invalid code, please try again.");
										case 417:
											// TODO: This shouldn't be a thing?, but its in the API doc?
											textsecure.throwHumanError(code, "HTTPError", "Number already registered.");
										case 401:
											textsecure.throwHumanError(code, "HTTPError", "Invalid authentication, most likely someone re-registered and invalidated our registration.");
										case 404:
											textsecure.throwHumanError(code, "HTTPError", "Number is not registered with TextSecure.");
										default:
											textsecure.throwHumanError(code, "HTTPError", "The server rejected our query, please file a bug report.");
										}
									} catch (e) {
										if (jqXHR.responseJSON)
											e.response = jqXHR.responseJSON;
										reject(e);
									}
								}
			});
		});
	};

	self.requestVerificationCode = function(number) {
		return doAjax({
			call				: 'accounts',
			httpType			: 'GET',
			urlParameters		: '/sms/code/' + number,
		});
	};

	self.confirmCode = function(number, code, password,
								signaling_key, registrationId, single_device) {
			var call = single_device ? 'accounts' : 'devices';
			var urlPrefix = single_device ? '/code/' : '/';

			return doAjax({
				call				: call,
				httpType			: 'PUT',
				urlParameters		: urlPrefix + code,
				user				: number,
				password			: password,
				jsonData			: { signalingKey		: btoa(getString(signaling_key)),
											supportsSms		: false,
											fetchesMessages	: true,
											registrationId	: registrationId},
			});
	};

	self.registerKeys = function(genKeys) {
		var keys = {};
		keys.identityKey = btoa(getString(genKeys.identityKey));
		keys.signedPreKey = {keyId: genKeys.signedPreKey.keyId, publicKey: btoa(getString(genKeys.signedPreKey.publicKey)),
							signature: btoa(getString(genKeys.signedPreKey.signature))};

		keys.preKeys = [];
		var j = 0;
		for (i in genKeys.preKeys)
			keys.preKeys[j++] = {keyId: i, publicKey: btoa(getString(genKeys.preKeys[i].publicKey))};

		//TODO: This is just to make the server happy (v2 clients should choke on publicKey),
		// it needs removed before release
		keys.lastResortKey = {keyId: 0x7fffFFFF, publicKey: btoa("42")};

		return doAjax({
			call				: 'keys',
			httpType			: 'PUT',
			do_auth				: true,
			jsonData			: keys,
		});
	};

	self.getKeysForNumber = function(number) {
		return doAjax({
			call				: 'keys',
			httpType			: 'GET',
			do_auth				: true,
			urlParameters		: "/" + number + "/*",
		}).then(function(res) {
			var promises = [];
			res.identityKey = base64DecToArr(res.identityKey);
			for (var i = 0; i < res.devices.length; i++) {
				res.devices[i].signedPreKey.publicKey = base64DecToArr(res.devices[i].signedPreKey.publicKey);
				res.devices[i].signedPreKey.signature = base64DecToArr(res.devices[i].signedPreKey.signature);
				promises[i] = window.textsecure.crypto.Ed25519Verify(res.identityKey, res.devices[i].signedPreKey.publicKey, res.devices[i].signedPreKey.signature);
				res.devices[i].preKey.publicKey = base64DecToArr(res.devices[i].preKey.publicKey);
				//TODO: Is this still needed?
				//if (res.devices[i].keyId === undefined)
				//	res.devices[i].keyId = 0;
			}
			return Promise.all(promises).then(function() {
				return res;
			});
		});
	};

	self.sendMessages = function(destination, messageArray) {
		//TODO: Do this conversion somewhere else?
		for (var i = 0; i < messageArray.length; i++)
			messageArray[i].body = btoa(messageArray[i].body);
		var jsonData = { messages: messageArray };
		if (messageArray[0].relay !== undefined)
			jsonData.relay = messageArray[0].relay;
		
		return doAjax({
			call				: 'messages',
			httpType			: 'PUT',
			urlParameters		: '/' + destination,
			do_auth				: true,
			jsonData			: jsonData,
		});
	};

	self.getAttachment = function(id) {
		return doAjax({
			call				: 'attachment',
			httpType			: 'GET',
			urlParameters		: '/' + id,
			do_auth				: true,
		}).then(function(response) {
			return new Promise(function(resolve, reject) {
				$.ajax(response.location, {
					type		: "GET",
					xhrFields: {
						responseType: "arraybuffer"
					},
					headers: {
						"Content-Type": "application/octet-stream"
					},

					success		: function(response, textStatus, jqXHR) {
										resolve(response);
									},

					error		: function(jqXHR, textStatus, errorThrown) {
										var code = jqXHR.status;
										if (code > 999 || code < 100)
											code = -1;

										var e = new Error(code);
										e.name = "HTTPError";
										if (jqXHR.responseJSON)
											e.response = jqXHR.responseJSON;
										reject(e);
									}
				});
			});
		});
	};

	self.putAttachment = function(encryptedBin) {
		return doAjax({
			call				: 'attachment',
			httpType			: 'GET',
			do_auth				: true,
		}).then(function(response) {
			return new Promise(function(resolve, reject) {
				$.ajax(response.location, {
					type		: "PUT",
					headers: {
						"Content-Type": "application/octet-stream"
					},
					data: encryptedBin,

					success		: function() {
										resolve(response.id);
									},

					error		: function(jqXHR, textStatus, errorThrown) {
										var code = jqXHR.status;
										if (code > 999 || code < 100)
											code = -1;

										var e = new Error(code);
										e.name = "HTTPError";
										if (jqXHR.responseJSON)
											e.response = jqXHR.responseJSON;
										reject(e);
									}
				});
			});
		});
	};

	self.getWebsocket = function() {
		var user = textsecure.storage.getUnencrypted("number_id");
		var password = textsecure.storage.getEncrypted("password");
		var URL = URL_BASE.replace(/^http/g, 'ws') + URL_CALLS['push'] + '/?';
		var params = $.param({
			login: '+' + getString(user).substring(1),
			password: getString(password)
		});
		return new WebSocket(URL+params);
	}

	return self;
}();