(ns glimmer-vidya.showcase
  "Every tag this backend paints, in one scrolling page.

  It is also the reconciler's exercise: the task list is a keyed list that is
  added to, removed from and reordered, so widgets are reused and moved rather
  than rebuilt."
  (:require [glimmer.ratom :as r :refer [atom]]
            [glimmer.core :as ui]
            [glimmer-vidya.core :as vidya]))

(defonce tasks (atom [{:id 1 :text "Wire egui into glimmer" :done true}
                      {:id 2 :text "Reconcile a keyed list" :done false}
                      {:id 3 :text "Ship it" :done false}]))
(defonce draft (atom ""))
(defonce next-id (atom 4))
(defonce progress (atom 0.0))
(defonce live? (atom true))

(defn- add-task! []
  (let [text @draft]
    (when (seq text)
      (swap! tasks conj {:id (swap! next-id inc) :text text :done false})
      (reset! draft ""))))

(defn- toggle! [id]
  (swap! tasks (fn [ts] (mapv #(if (= id (:id %)) (update % :done not) %) ts))))

(defn- drop-task! [id]
  (swap! tasks (fn [ts] (filterv #(not= id (:id %)) ts))))

(defn task-row [task]
  [:hbox {:key (:id task) :spacing 12}
   [:checkbutton {:label (:text task)
                  :active (:done task)
                  :on-toggled #(toggle! (:id task))}]
   [:button {:label "remove"
             :kind :destructive
             :on-click #(drop-task! (:id task))}]])

(defn app []
  [:page {:max-width 620}
   [:title {:label "Vidya + glimmer"}]
   [:dim-label {:label "Reactive components, painted by egui."}]

   [:card {}
    [:title-2 {:label "Tasks"}]
    (for [task @tasks] [task-row task])
    (when (empty? @tasks) [:dim-label {:label "Nothing left."}])
    [:separator {}]
    [:hbox {:spacing 8}
     [:entry {:text @draft
              :width-request 380
              :placeholder "What needs doing?"
              :on-change #(reset! draft %)
              :on-activate add-task!}]
     [:button {:label "Add" :kind :primary :on-click add-task!}]]]

   [:card {}
    [:title-2 {:label "Feedback"}]
    [:status {:label (if @live? "Connected" "Offline") :live @live?}]
    [:progress {:value @progress :label (str (int (* 100 @progress)) "%")}]
    [:hbox {:spacing 8}
     [:button {:label "Toggle connection" :on-click #(swap! live? not)}]
     [:button {:label "Advance"
               :on-click #(swap! progress (fn [v] (if (>= v 1.0) 0.0 (+ v 0.2))))}]]]

   [:card {}
    [:title-2 {:label "Disabled subtree"}]
    [:vbox {:spacing 6 :sensitive false}
     [:label {:label "Nothing in here answers to the pointer."}]
     [:button {:label "Unreachable"}]]]

   [:hbox {:spacing 8}
    [:button {:label "Quit" :on-click vidya/quit!}]]])

(defn -main [& _]
  (ui/run app :title "glimmer-vidya showcase" :width 760 :height 720))