core.clj

(ns weather.core
  (:require [clj-http.client :as http]))

;; utility Functionsp
(def weather-api
  "http://api.openweathermap.org/data/2.5/")

(defn weather-find [something]
  (let [response (http/get (str weather-api "find")
                           {:query-params {:q something}
                            :as :json})]
    (:body response)))

(defn weather-forecast [loc days]
  (let [response (http/get (str weather-api "forecast/daily")
                           {:query-params {:q loc
                                           :cnt days
                                           :units "metric"}
                            :as :json})]
    (:list (:body response))))

(defn get-london []
  (weather-find "London"))

(defn get-londons []
  (map :sys (:list (get-london))))

;; Get coordinates of all Londons
(defn get-coords []
  (map :coord (:list (weather-find "London"))))

(defn avg [v]
  (/ (reduce + v) (count v)))

;; What has been the average temp in London over n past days.
(defn average-temp-n-days [n]
  (avg (map #(get-in % [:temp :day])
            (weather-forecast "London,UK" n))))

;; On how many of the next 10 days it will be  cloudy (> 40% cloudy)
(defn clouds []
  (count (filter #(> (% :clouds) 40)
                 (weather-forecast "London,UK" 10))))