local http = require "http"
local json = require "json"
local package = require "package"
local stdnse = require "stdnse"
local table = require "table"
_ENV = stdnse.module("mobileme", stdnse.seeall)

---
-- A MobileMe web service client that allows discovering Apple devices
-- using the "find my iPhone" functionality. 
-- 
-- @author "Patrik Karlsson <patrik@cqure.net>"
--

MobileMe = {
	
	-- headers used in all requests
	headers = { 
		["Content-Type"] = "application/json; charset=utf-8",
    	["X-Apple-Find-Api-Ver"] = "2.0",
    	["X-Apple-Authscheme"] = "UserIdGuest",
    	["X-Apple-Realm-Support"] = "1.0",
    	["User-Agent"] = "Find iPhone/1.3 MeKit (iPad: iPhone OS/4.2.1)",
    	["X-Client-Name"] = "iPad",
    	["X-Client-UUID"] = "0cf3dc501ff812adb0b202baed4f37274b210853",
    	["Accept-Language"] = "en-us",
    	["Connection"] = "keep-alive"
	},
	
	-- Creates a MobileMe instance
	-- @param username string containing the Apple ID username
	-- @param password string containing the Apple ID password
	-- @return o new instance of MobileMe
	new = function(self, username, password)
		local o = {
			host = "fmipmobile.icloud.com",
			port = 443,
			username = username,
			password = password
		}
		setmetatable(o, self)
		self.__index = self
		return o
	end,
	
	-- Sends a message to an iOS device
	-- @param devid string containing the device id to which the message should
	--        be sent
	-- @param subject string containing the messsage subject
	-- @param message string containing the message body
	-- @param alarm boolean true if alarm should be sounded, false if not
	-- @return status true on success, false on failure
	-- @return err string containing the error message (if status is false)
	sendMessage = function(self, devid, subject, message, alarm)
		local data = '{"clientContext":{"appName":"FindMyiPhone","appVersion":"1.3","buildVersion":"145","deviceUDID":"0000000000000000000000000000000000000000","inactiveTime":5911,"osVersion":"3.2","productType":"iPad1,1","selectedDevice":"%s","shouldLocate":false},"device":"%s","serverContext":{"callbackIntervalInMS":3000,"clientId":"0000000000000000000000000000000000000000","deviceLoadStatus":"203","hasDevices":true,"lastSessionExtensionTime":null,"maxDeviceLoadTime":60000,"maxLocatingTime":90000,"preferredLanguage":"en","prefsUpdateTime":1276872996660,"sessionLifespan":900000,"timezone":{"currentOffset":-25200000,"previousOffset":-28800000,"previousTransition":1268560799999,"tzCurrentName":"Pacific Daylight Time","tzName":"America/Los_Angeles"},"validRegion":true},"sound":%s,"subject":"%s","text":"%s"}'
		data = data:format(devid, devid, tostring(alarm), subject, message)

		local url = ("/fmipservice/device/%s/sendMessage"):format(self.username)
	    local auth = { username = self.username, password = self.password }

		local response = http.post(self.host, self.port, url, { header = self.headers, auth = auth, timeout = 10000 }, nil, data)
		
		if ( response.status == 200 ) then
			local status, resp = json.parse(response.body)
			if ( not(status) ) then
				stdnse.print_debug(2, "Failed to parse JSON response from server")
				return false, "Failed to parse JSON response from server"
			end
			
			if ( resp.statusCode ~= "200" ) then
				stdnse.print_debug(2, "Failed to send message to server")
				return false, "Failed to send message to server"
			end
		end
		return true
	end,
	
	-- Updates location information for all devices controlled by the Apple ID
	-- @return status true on success, false on failure
	-- @return json parsed json table or string containing an error message on
	--         failure
	update = function(self)

	    local auth = {
			username = self.username,
			password = self.password
		}

		local url = ("/fmipservice/device/%s/initClient"):format(self.username)
		local data= '{"clientContext":{"appName":"FindMyiPhone","appVersion":"1.3","buildVersion":"145","deviceUDID":"0000000000000000000000000000000000000000","inactiveTime":2147483647,"osVersion":"4.2.1","personID":0,"productType":"iPad1,1"}}'

		local retries = 2

		local response
		repeat
			response = http.post(self.host, self.port, url, { header = self.headers, auth = auth }, nil, data)
			if ( response.header["x-apple-mme-host"] ) then
				self.host = response.header["x-apple-mme-host"]
			end
			
			if ( response.status == 401 ) then
				return false, "Authentication failed"
			elseif ( response.status ~= 200 and response.status ~= 330 ) then
				return false, "An unexpected error occured"
			end
			
			retries = retries - 1
		until ( 200 == response.status or 0 == retries)

		if ( response.status ~= 200 ) then
			return false, "Received unexpected response from server"
		end
		
		local status, parsed_json = json.parse(response.body)

		if ( not(status) or parsed_json.statusCode ~= "200" ) then
			return false, "Failed to parse JSON response from server"
		end

		-- cache the parsed_json.content as devices
		self.devices = parsed_json.content

		return true, parsed_json
	end,
	
	-- Get's a list of devices
	-- @return devices table containing a list of devices
	getDevices = function(self)
		if ( not(self.devices) ) then
			self:update()
		end
		return self.devices
	end
}


Helper = {

	
	-- Creates a Helper instance
	-- @param username string containing the Apple ID username
	-- @param password string containing the Apple ID password
	-- @return o new instance of Helper
	new = function(self, username, password)
		local o = {
			mm = MobileMe:new(username, password)
		}
		setmetatable(o, self)
		self.__index = self
		o.mm:update()
		return o
	end,
	
	-- Get's the geolocation from each device
	--
	-- @return status true on success, false on failure
	-- @return result table containing a table of device locations
	--         the table is indexed based on the name of the device and
	--         contains a location table with the following fields:
	--         * <code>longitude</code> - the GPS longitude
	--         * <code>latitude</code>  - the GPS latitude
	--         * <code>accuracy</code>  - the location accuracy
	--         * <code>timestamp</code> - the time the location was acquired
	--         * <code>postype</code>   - the position type (GPS or WiFi)
	--         * <code>finished</code>  - 
	--         or string containing an error message on failure
	getLocation = function(self)
		-- do 3 tries, with a 5 second timeout to allow the location to update
		-- there are two attributes, locationFinished and isLocating that seem
		-- to be good candidates to monitor, but so far, I haven't had any
		-- success with that.
		local tries, timeout = 3, 5
		local result = {}
		
		repeat
			local status, response = self.mm:update()
			
			if ( not(status) or not(response) ) then
				return false, "Failed to retrieve response from server"
			end
			for _, device in ipairs(response.content) do
				if ( device.location ) then
					result[device.name] = {
						longitude = device.location.longitude,
						latitude = device.location.latitude,
						accuracy = device.location.horizontalAccuracy,
						timestamp = device.location.timeStamp,
						postype   = device.location.positionType,
						finished = device.location.locationFinished,
					}
				end
			end
			tries = tries - 1
			if ( tries > 0 ) then
				stdnse.sleep(timeout)
			end
		until( tries == 0 )
		return true, result
	end,
	
	-- Gets a list of names and ids of devices associated with the Apple ID
	-- @return status true on success, false on failure
	-- @return table of devices containing the following fields:
	--         <code>name</code> and <code>id</code>
	getDevices = function(self)
		local devices = {}
		for _, dev in ipairs(self.mm:getDevices()) do
			table.insert(devices, { name = dev.name, id = dev.id })
		end
		return true, devices
	end,
	
	-- Send a message to an iOS Device
	--
	-- @param devid string containing the device id to which the message should
	--        be sent
	-- @param subject string containing the messsage subject
	-- @param message string containing the message body
	-- @param alarm boolean true if alarm should be sounded, false if not
	-- @return status true on success, false on failure
	-- @return err string containing the error message (if status is false)
	sendMessage = function(self, ...)
		return self.mm:sendMessage(...)
	end
	
}

return _ENV;
