Build exchange algorithm with cex.io API in brief script -- 3

i need a webpage that has a username and password to access and automated timely exchanges in [login to view URL] with their API when I create account on this page I add info needed for API to function. Given 4 fields on the page after login: Sell/Buy amount: xxxxxx ETH/BTC exchange USD/EUR Percent: [login to view URL] % Automated Notice time exchange limit: y min Update me of change: z min (exchange USD/EUR set same as Sell/Buy amount) Start/Stop Button script will execute in a timely looped fashion until clicking the stop button algorithm logic: sell amount will be set in trade for exchange by other buyers with the current ETH/BTC value times Percent (ETH/BTC Value * (100 + [login to view URL]) ) to USD/EUR. When sold: Buy amount same as sell amount from same set field will be set in trade for purchase by other buyers with the current ETH/BTC value times Percent (ETH/BTC Value * (100 - [login to view URL]) ) to USD/EUR. email will be sent: if-> exchange did not go through in Automated Notice time period allerting user. if-> Update me of change is reached sending current USD/EUR amount in account