Added script to export piece sets for Lichess

scripts/createLichessPiecesCSS.js

@@ -0,0 +1,52 @@
+const fs = require("fs");
+
+const files = fs.readdirSync("_release_assets/encoded_pieces");
+
+const piecesNames = {
+  p: "pawn",
+  b: "bishop",
+  r: "rook",
+  n: "knight",
+  q: "queen",
+  k: "king",
+};
+
+const piecesColors = {
+  b: "black",
+  w: "white",
+};
+
+for (const file of files) {
+  const [name] = file.split(".");
+
+  const data = JSON.parse(
+    fs.readFileSync(`_release_assets/encoded_pieces/${file}`, {
+      encoding: "utf8",
+    })
+  );
+
+  const css = data
+    .map(([key, dataURL]) => {
+      const [piece, color] = key.split("");
+
+      return `.is2d .${piecesNames[piece]}.${piecesColors[color]} {background-image:url('${dataURL}')}`;
+    })
+    .join("\n");
+
+  fs.writeFileSync(`_release_assets/lichess_css/${name}.css`, css);
+
+  const cssExternal = data
+    .map(([key]) => {
+      const [piece, color] = key.split("");
+
+      return `.is2d .${piecesNames[piece]}.${
+        piecesColors[color]
+      } {background-image:url('/assets/piece/${name}/${color}${piece.toUpperCase()}.svg')}`;
+    })
+    .join("\n");
+
+  fs.writeFileSync(
+    `_release_assets/lichess_css/${name}.external.css`,
+    cssExternal
+  );
+}