(in-package #:chatikbot)

(defparameter +yahoo-url+ "https://query.yahooapis.com/v1/public/yql" "Yahoo Finance API endpoint")
(defparameter +yahoo-query+ "select Name,Rate from yahoo.finance.xchange where pair in (~{\"~A\"~^,~})")

(defvar *rate-pairs* '("USDRUB" "EURRUB" "GBPRUB"))

(defun get-rates (&optional (pairs *rate-pairs*))
  (let ((response (yason:parse
		   (flexi-streams:octets-to-string
		    (drakma:http-request +yahoo-url+
					 :parameters (append '(("format" . "json")
							       ("env" . "store://datatables.org/alltableswithkeys"))
							     (list (cons "q" (format nil +yahoo-query+ pairs)))))
		    :external-format :utf-8)
		   :object-as :alist)))
    (when (aget "error" response)
      (error "Error in rates request"))
    (loop for rate in (aget "rate" (aget "results" (aget "query" response)))
       collect (cons (aget "Name" rate)
		     (aget "Rate" rate)))))