(ns examples.list-selection
  "List selection example - demonstrates cursor navigation and multi-select.
   Mirrors bubbletea's list examples."
  (:require [tui.core :as tui]
            [clojure.string :as str]))

;; === Model ===
(def initial-model
  {:cursor 0
   :items ["Pizza" "Sushi" "Tacos" "Burger" "Pasta" "Salad" "Soup" "Steak"]
   :selected #{}
   :submitted false})

;; === Update ===
(defn update-model [{:keys [cursor items] :as model} msg]
  (cond
    ;; Quit
    (or (tui/key= msg "q")
        (tui/key= msg [:ctrl \c]))
    [model tui/quit]

    ;; Move up
    (or (tui/key= msg :up)
        (tui/key= msg "k"))
    [(update model :cursor #(max 0 (dec %))) nil]

    ;; Move down
    (or (tui/key= msg :down)
        (tui/key= msg "j"))
    [(update model :cursor #(min (dec (count items)) (inc %))) nil]

    ;; Toggle selection
    (tui/key= msg " ")
    [(update model :selected
             #(if (contains? % cursor)
                (disj % cursor)
                (conj % cursor)))
     nil]

    ;; Submit
    (tui/key= msg :enter)
    [(assoc model :submitted true) tui/quit]

    :else
    [model nil]))

;; === View ===
(defn view [{:keys [cursor items selected submitted]}]
  (if submitted
    [:col
     [:text {:bold true :fg :green} "You selected:"]
     [:text ""]
     (if (empty? selected)
       [:text {:fg :gray} "(nothing selected)"]
       [:col
        (for [idx (sort selected)]
          [:text (str "  - " (nth items idx))])])]

    [:col {:gap 1}
     [:box {:border :rounded :padding [0 1] :title "What's for lunch?"}
      [:col
       (for [[idx item] (map-indexed vector items)]
         (let [is-cursor (= idx cursor)
               is-selected (contains? selected idx)]
           [:row {:gap 1}
            [:text {:fg (when is-cursor :cyan)} (if is-cursor ">" " ")]
            [:text (if is-selected "[x]" "[ ]")]
            [:text {:bold is-cursor
                    :fg (cond
                          is-selected :green
                          is-cursor :cyan
                          :else :default)}
             item]]))]]
     [:row {:gap 2}
      [:text {:fg :gray} "j/k: move"]
      [:text {:fg :gray} "space: select"]
      [:text {:fg :gray} "enter: confirm"]
      [:text {:fg :gray} "q: quit"]]
     [:text {:fg :cyan}
      (str (count selected) " item" (when (not= 1 (count selected)) "s") " selected")]]))

;; === Main ===
(defn -main [& _args]
  (println "Starting list selection...")
  (let [{:keys [items selected submitted]} (tui/run {:init initial-model
                                                     :update update-model
                                                     :view view})]
    (when submitted
      (println)
      (println "Your order:")
      (doseq [idx (sort selected)]
        (println "  -" (nth items idx))))))