;; This Source Code Form is subject to the terms of the Mozilla Public
;; License, v. 2.0. If a copy of the MPL was not distributed with this
;; file, You can obtain one at http://mozilla.org/MPL/2.0/.
;;
;; Copyright (c) KALEIDOS SUBSIDIARY SL

(ns frontend-tests.render-wasm.text-paste-test
  "Restyling pasted text. Test content already holds the pasted text in the
   style of the span it went into, as after `text-editor-sync-content`."
  (:require
   [app.render-wasm.text-paste :as text-paste]
   [cljs.test :as t :include-macros true]))

(def ^:private regular
  {:font-id "sourcesanspro" :font-variant-id "regular"
   :font-weight "400" :font-style "normal"})

(defn- span
  ([text] (span text {}))
  ([text attrs] (merge regular attrs {:text text})))

(defn- content [& paragraphs]
  {:type "root"
   :children [{:type "paragraph-set"
               :children (mapv (fn [spans] {:type "paragraph" :children spans})
                               paragraphs)}]})

(defn- spans-of [content]
  (mapv :children (-> content :children first :children)))

(defn- fragment-paragraph [& runs]
  {:attrs {} :children (vec runs)})

(defn- run
  ([text] (run text {}))
  ([text attrs] {:text text :attrs attrs}))

(def ^:private bold-variant
  {:font-weight "700" :font-style "normal" :font-variant-id "bold"})

(t/deftest fragment->text
  (t/testing "paragraphs are joined by newlines"
    (t/is (= "ab\n\nc"
             (text-paste/fragment->text
              [(fragment-paragraph (run "a") (run "b"))
               (fragment-paragraph)
               (fragment-paragraph (run "c"))])))))

(t/deftest bold-run-resolves-to-a-font-variant
  (t/testing "a bold run inside a paragraph gets the bold variant of the span's font"
    (let [pasted   (content [(span "Hello big world")])
          fragment [(fragment-paragraph (run "big " {:font-weight "700"}))]
          result   (text-paste/apply-fragment-styles pasted fragment {:para 0 :offset 6})]
      (t/is (= [[(span "Hello ") (span "big " bold-variant) (span "world")]]
               (spans-of result))))))

(t/deftest italic-run-keeps-the-span-weight
  (t/testing "italic over a bold span picks the bold italic variant"
    (let [pasted   (content [(span "x" bold-variant)])
          fragment [(fragment-paragraph (run "x" {:font-style "italic"}))]
          result   (text-paste/apply-fragment-styles pasted fragment {:para 0 :offset 0})]
      (t/is (= [[(span "x" {:font-weight "700" :font-style "italic"
                            :font-variant-id "bolditalic"})]]
               (spans-of result))))))

(t/deftest html-emphasis-replaces-the-caret-emphasis
  (let [no-emphasis {:font-weight "400" :font-style "normal"
                     :text-decoration "none" :text-transform "none"}]
    (t/testing "plain source text pasted into bold, underlined text comes out plain"
      (let [pasted   (content [(span "aXb" (assoc bold-variant :text-decoration "underline"))])
            fragment [(fragment-paragraph (run "X" no-emphasis))]
            result   (text-paste/apply-fragment-styles pasted fragment {:para 0 :offset 1})]
        (t/is (= [[(span "a" (assoc bold-variant :text-decoration "underline"))
                   (span "X" {:text-decoration "none" :text-transform "none"})
                   (span "b" (assoc bold-variant :text-decoration "underline"))]]
                 (spans-of result)))))

    (t/testing "not bold leaves a light weight as it is"
      (let [light    {:font-weight "300" :font-style "normal" :font-variant-id "300"}
            pasted   (content [(span "X" light)])
            fragment [(fragment-paragraph (run "X" no-emphasis))]
            result   (text-paste/apply-fragment-styles pasted fragment {:para 0 :offset 0})]
        (t/is (= [[(span "X" (assoc light :text-decoration "none" :text-transform "none"))]]
                 (spans-of result)))))))

(t/deftest unknown-font-keeps-its-weight
  (t/testing "a font we have no data for cannot resolve a variant, so it stays"
    (let [unknown  (span "x" {:font-id "missing-font"})
          fragment [(fragment-paragraph (run "x" {:font-weight "700"}))]
          result   (text-paste/apply-fragment-styles (content [unknown]) fragment {:para 0 :offset 0})]
      (t/is (= [[unknown]] (spans-of result))))))

(t/deftest typography-link
  (let [linked {:typography-ref-id "typo-id" :typography-ref-file "file-id"}]
    (t/testing "a span changed by the paste leaves its typography"
      (let [fragment [(fragment-paragraph (run "x" {:text-decoration "underline"}))]
            result   (text-paste/apply-fragment-styles
                      (content [(span "x" linked)]) fragment {:para 0 :offset 0})]
        (t/is (= [[(span "x" {:text-decoration "underline"})]]
                 (spans-of result)))))

    (t/testing "a span the paste leaves as it was keeps its typography"
      (let [already  (span "x" (merge bold-variant linked))
            fragment [(fragment-paragraph (run "x" {:font-weight "700"}))]
            result   (text-paste/apply-fragment-styles (content [already]) fragment {:para 0 :offset 0})]
        (t/is (= [[already]] (spans-of result)))))))

(t/deftest ranges-across-paragraphs
  (t/testing "runs after the first paragraph start at offset 0 of their paragraph"
    (let [pasted   (content [(span "abX")] [(span "Ycd")])
          fragment [(fragment-paragraph (run "X" {:font-weight "700"}))
                    (fragment-paragraph (run "Y" {:font-weight "700"}))]
          result   (text-paste/apply-fragment-styles pasted fragment {:para 0 :offset 2})]
      (t/is (= [[(span "ab") (span "X" bold-variant)]
                [(span "Y" bold-variant) (span "cd")]]
               (spans-of result))))))

(t/deftest ranges-count-utf16-units
  (t/testing "an emoji in the fragment moves later runs by its two UTF-16 units"
    (let [pasted   (content [(span "😀b")])
          fragment [(fragment-paragraph (run "😀") (run "b" {:font-weight "700"}))]
          result   (text-paste/apply-fragment-styles pasted fragment {:para 0 :offset 0})]
      (t/is (= [[(span "😀") (span "b" bold-variant)]]
               (spans-of result)))))

  (t/testing "a paste after an emoji starts at the UTF-16 offset WASM reports"
    (let [pasted   (content [(span "😀Xb")])
          fragment [(fragment-paragraph (run "X" {:font-weight "700"}))]
          result   (text-paste/apply-fragment-styles pasted fragment {:para 0 :offset 2})]
      (t/is (= [[(span "😀") (span "X" bold-variant) (span "b")]]
               (spans-of result))))))

(t/deftest fragment->content
  (t/testing "runs become spans over the base style, and empty paragraphs keep one empty span"
    (let [result (text-paste/fragment->content
                  [(fragment-paragraph (run "Hello ") (run "bold" {:font-weight "700"}))
                   (fragment-paragraph)]
                  regular)]
      (t/is (= [[(span "Hello ") (span "bold" bold-variant)]
                [(span "")]]
               (spans-of result)))))

  (t/testing "paragraphs carry the base style"
    (let [result (text-paste/fragment->content [(fragment-paragraph (run "x"))] regular)]
      (t/is (= (assoc regular :type "paragraph")
               (dissoc (-> result :children first :children first) :children))))))

;; --- Text copied in Penpot

(def ^:private brand
  {:font-id "gfont-roboto" :font-family "Roboto" :font-variant-id "700italic"
   :font-weight "700" :font-style "italic"
   :fills [{:fill-color "#ff0000" :fill-opacity 1}]})

(t/deftest content->fragment
  (t/testing "paragraphs and spans keep their whole style, and empty spans are dropped"
    (t/is (= [{:attrs {:text-align "center"}
               :children [{:text "x" :attrs brand}]}
              {:attrs {:text-align "right"}
               :children []}]
             (text-paste/content->fragment
              {:type "root"
               :children [{:type "paragraph-set"
                           :children [{:type "paragraph" :text-align "center"
                                       :children [(assoc brand :text "x") (assoc brand :text "")]}
                                      {:type "paragraph" :text-align "right"
                                       :children [(assoc brand :text "")]}]}]})))))

(t/deftest penpot-styles-replace-the-caret-style
  (t/testing "pasted runs take their whole style, dropping the target's typography"
    (let [pasted   (content [(span "AxyB" {:typography-ref-id "t" :typography-ref-file "f"})])
          fragment [(fragment-paragraph (run "x" brand) (run "y" regular))]
          result   (text-paste/apply-content-styles pasted fragment {:para 0 :offset 1})]
      (t/is (= [[(span "A" {:typography-ref-id "t" :typography-ref-file "f"})
                 (assoc brand :text "x")
                 (span "y")
                 (span "B" {:typography-ref-id "t" :typography-ref-file "f"})]]
               (spans-of result)))))

  (t/testing "the first paragraph keeps its style; later ones bring theirs"
    (let [pasted   {:type "root"
                    :children [{:type "paragraph-set"
                                :children [{:type "paragraph" :text-align "left" :children [(span "Ax")]}
                                           {:type "paragraph" :text-align "left" :children [(span "yB")]}]}]}
          fragment [{:attrs {:text-align "center"} :children [(run "x" brand)]}
                    {:attrs {:text-align "right"} :children [(run "y" brand)]}]
          result   (text-paste/apply-content-styles pasted fragment {:para 0 :offset 1})]
      (t/is (= ["left" "right"]
               (map :text-align (-> result :children first :children))))
      (t/is (= [[(span "A") (assoc brand :text "x")]
                [(assoc brand :text "y") (span "B")]]
               (spans-of result))))))

;; --- Gradients

(defn- gradient-fill [gradient]
  {:fills [{:fill-color-gradient (merge {:type :linear :width 1 :stops []} gradient)}]})

(def ^:private source-box {:width 200 :height 40})

(def ^:private target-box {:width 100 :height 80})

(def ^:private source-geometry
  {:origins [[{:x 50 :y 0 :box source-box}]]})

(def ^:private target-geometry
  {:origins [[{:x 10 :y 40 :box target-box}]]})

(defn- pasted-gradient [content]
  (-> (spans-of content) first second :fills first :fill-color-gradient))

(t/deftest gradients-keep-their-offset-from-the-span
  (let [linear (gradient-fill {:start-x 0.25 :start-y 0 :end-x 0.75 :end-y 1})
        pasted (content [(span "HELLO" linear)])
        target (content [(span "abc") (span "HELLO" linear)])
        result (text-paste/move-span-fills target pasted {:para 0 :offset 3}
                                           source-geometry target-geometry)]
    (t/testing "points move into the target box at the same pixel offsets"
      (t/is (= {:start-x 0.1 :start-y 0.5 :end-x 1.1 :end-y 1}
               (select-keys (pasted-gradient result) [:start-x :start-y :end-x :end-y]))))
    (t/testing "a linear width stays as it was"
      (t/is (= 1 (:width (pasted-gradient result)))))
    (t/testing "text before the paste keeps its fills"
      (t/is (= (span "abc") (-> (spans-of result) first first))))))

(t/deftest radial-width-follows-the-aspect-ratio
  (let [radial (gradient-fill {:type :radial :start-x 0.5 :start-y 0.5 :end-x 0.5 :end-y 1})
        pasted (content [(span "HELLO" radial)])
        target (content [(span "abc") (span "HELLO" radial)])
        result (text-paste/move-span-fills target pasted {:para 0 :offset 3}
                                           source-geometry target-geometry)]
    ;; 200x40 is 5:1 and 100x80 is 5:4, so the width grows 4 times.
    (t/is (= 4 (:width (pasted-gradient result))))))

(t/deftest spans-without-geometry-are-left-alone
  (let [red    {:fills [{:fill-color "#ff0000" :fill-opacity 1}]}
        linear (gradient-fill {:start-x 0 :start-y 0 :end-x 1 :end-y 1})
        pasted (content [(span "red" red) (span "grad" linear)])
        target (content [(span "red" red) (span "grad" linear)])]
    (t/testing "a span with no origin keeps its gradient"
      (t/is (= target (text-paste/move-span-fills
                       target pasted {:para 0 :offset 0}
                       {:origins [[nil nil]]}
                       {:origins [[nil nil]]}))))
    (t/testing "an empty box leaves the gradients as they were"
      (t/is (= target (text-paste/move-span-fills
                       target pasted {:para 0 :offset 0}
                       {:origins [[nil {:x 0 :y 0 :box source-box}]]}
                       {:origins [[nil {:x 0 :y 0 :box {:width 0 :height 80}}]]}))))))

(t/deftest each-span-moves-from-its-own-box
  ;; Copied text shapes are joined into one paste, each span keeping its box.
  (let [linear (gradient-fill {:start-x 0.5 :start-y 0 :end-x 0.5 :end-y 1})
        pasted (content [(span "a" linear)] [(span "b" linear)])
        source {:origins [[{:x 0 :y 0 :box {:width 100 :height 20}}]
                          [{:x 0 :y 0 :box {:width 200 :height 40}}]]}
        target {:origins [[{:x 0 :y 0 :box {:width 400 :height 80}}]
                          [{:x 0 :y 40 :box {:width 400 :height 80}}]]}
        result (text-paste/move-span-fills pasted pasted {:para 0 :offset 0} source target)
        points #(select-keys (-> % :fills first :fill-color-gradient)
                             [:start-x :start-y :end-x :end-y])]
    (t/is (= [{:start-x 0.125 :start-y 0 :end-x 0.125 :end-y 0.25}
              {:start-x 0.25 :start-y 0.5 :end-x 0.25 :end-y 1}]
             (map (comp points first) (spans-of result))))))

;; --- Images

(defn- image-fill [image]
  {:fills [{:fill-image (merge {:id #uuid "00000000-0000-0000-0000-000000000042"
                                :width 400 :height 200 :mtype "image/png"}
                               image)}]})

(defn- pasted-image-transform [content]
  (-> (spans-of content) first second :fills first :fill-image :transform))

(t/deftest images-keep-their-offset-from-the-span
  (let [move (fn [image]
               (let [fill (image-fill image)]
                 (pasted-image-transform
                  (text-paste/move-span-fills (content [(span "abc") (span "HELLO" fill)])
                                              (content [(span "HELLO" fill)])
                                              {:para 0 :offset 3}
                                              source-geometry target-geometry))))]
    (t/testing "an image over the whole source box gets a transform over the same pixels"
      (t/is (= {:x -0.4 :y 0.5 :width 2 :height 0.5}
               (move {}))))
    (t/testing "an image with a transform keeps its pixel rect"
      (t/is (= {:x 0.1 :y 0.5 :width 1 :height 0.5}
               (move {:transform {:x 0.25 :y 0 :width 0.5 :height 1}}))))))