(ns myapp.typeahead
  (:require [reagent.core :as r]
            [goog.functions :as gf]
            [myapp.api :as api]))


(defn input-control [props]
  (let [value        (r/atom (:default-value props ""))
        local-change #(reset! value (.. % -target -value))]
    (fn [{:keys [on-change] :as props}]
      [:input (assoc props
                :value @value
                :on-change (comp #(when (fn? on-change) (on-change %))
                                 local-change))])))


(defn create-typeahead-fetch [opts state]
  ;; or however you want to build your fetch handler
  (gf/debounce
    (partial api/fetch (:remote opts))
    (:debounce-ms opts 150)))


(defn typeahead [opts]
  (let [state  (r/atom {:open?    false
                        :loading? false
                        :results  nil
                        :error    nil})
        fetch  (create-typeahead-fetch state opts)
        toggle #(swap! state update :open? not)]
    (fn [opts]
      [:div
       (if (:open? @state)
         [input-control
          {:default-value (:default-value opts "")
           :on-change     fetch}]
         [button
          {:on-click toggle}
          "Show search"])
       (if (:loading? @state)
         [:div "Loading"]
         [:div (str (count (:results @state)) " results")])])))