(ns glimmer-jvui.props-check
  "Two prop-level bugs the tag diff could not see, checked against pixels.

  A tag being handled is not the same as a tag reading the props a client
  actually writes. Both of these rendered perfectly and said the wrong
  thing: a checkbutton whose tick never appeared because frq writes
  `:active` where this read `:checked`, and a field whose text ran out past
  its own border because nothing clipped it."
  (:require [glimmer.core :as ui]
            [glimmer-jvui.core]
            [jvui.sdl :as sdl]
            [jolt.ffi :as ffi]))

(defn- bmp [path]
  (let [b (java.nio.file.Files/readAllBytes
            (java.nio.file.Path/of path (into-array String [])))
        u (fn [i] (bit-and (int (aget b i)) 255))
        le (fn [i] (+ (u i) (bit-shift-left (u (+ i 1)) 8)
                      (bit-shift-left (u (+ i 2)) 16) (bit-shift-left (u (+ i 3)) 24)))
        off (le 10) w (le 18) h (le 22) stride (* 4 (quot (+ (* w 3) 3) 4))]
    {:w w :h h :px (fn [x y] (let [i (+ off (* (- h 1 y) stride) (* 3 x))]
                               {:b (u i) :g (u (+ i 1)) :r (u (+ i 2))}))}))

(defn- ink-in
  "How many pixels inside [x0 y0 x1 y1] differ from the background."
  [{:keys [px]} bg x0 y0 x1 y1]
  (count (for [y (range y0 y1) x (range x0 x1)
               :let [p (px x y)]
               :when (> (+ (abs (- (:r p) (:r bg))) (abs (- (:g p) (:g bg)))
                           (abs (- (:b p) (:b bg)))) 40)]
           1)))

(defn -main [& _]
  (let [shot (str (System/getProperty "java.io.tmpdir") "/jvui-props.bmp")
        out (atom []) ck! (fn [n ok?] (swap! out conj [n (boolean ok?)]))]
    (ui/run (fn []
              [:vbox {:spacing 8}
               ;; A card paints a background, so how wide it comes out is
               ;; visible. Nested two deep because frq's tree is nested:
               ;; every box shrink-wrapping is how its chat column ended
               ;; up a couple of hundred points wide in a wider window.
               [:vbox {} [:card {} [:label {:label "x"}]]]
               ;; :active, the way frq writes it — the tick must appear.
               [:checkbutton {:label "TLS" :active true}]
               ;; A string far wider than the field it is in.
               [:entry {:value "nandi-test.bsky.social-and-then-some-more-text"}]])
            {:title "props" :width 240 :height 140 :frames 6 :shot shot})
    (let [img (bmp shot)
          bg  ((:px img) 2 2)]
      ;; The tick is inside the little box at the far left of the first row.
      (ck! "an :active checkbutton draws its tick"
           (> (ink-in img bg 4 4 26 30) 12))
      ;; Nothing may be drawn to the right of the field's own border.
      (ck! "entry text stops at the field's edge"
           (zero? (ink-in img bg 232 100 240 140)))
      ;; The card's own background, out near the right edge: a
      ;; shrink-wrapped one would not reach.
      (ck! "a nested container fills the width"
           (pos? (ink-in img bg 200 4 232 40))))
    (doseq [[n ok?] @out] (println (if ok? "- " "FAIL ") n))
    (let [bad (remove second @out)]
      (println (if (seq bad) (str (count bad) " of " (count @out) " checks FAILED")
                   (str "all " (count @out) " checks passed")))
      (when (seq bad) (System/exit 1)))))