iosevka-bin: add support for variants

This adds the ability to select a specific prebuilt variant. It also adds
an updater script for generating their hashes. Additionally, switching
to TTC files reduces the package size by an order of magnitude.

Example usage:

	fonts.fonts = with pkgs; [
	  (iosevka-bin.override { variant = "ss10"; })
	  (iosevka-bin.override { variant = "sparkle"; })
	  (iosevka-bin.override { variant = "aile"; })
	];

pkgs/data/fonts/iosevka/bin.nix

@@ -1,20 +1,35 @@
-{ stdenv, fetchzip }:
+{ stdenv, lib, fetchurl, unzip
+, variant ? ""
+}:
 
 let
-  version = "3.4.6";
-in fetchzip {
-  name = "iosevka-bin-${version}";
+  name = "iosevka" + lib.optionalString (variant != "") "-" + variant;
 
-  url = "https://github.com/be5invis/Iosevka/releases/download/v${version}/ttc-iosevka-${version}.zip";
+  variantHashes = import ./variants.nix;
+  validVariants = map (lib.removePrefix "iosevka-")
+    (builtins.attrNames (builtins.removeAttrs variantHashes [ "iosevka" ]));
+in stdenv.mkDerivation rec {
+  pname = "${name}-bin";
+  version = "3.7.1";
 
-  postFetch = ''
+  src = fetchurl {
+    url = "https://github.com/be5invis/Iosevka/releases/download/v${version}/ttc-${name}-${version}.zip";
+    sha256 = variantHashes.${name} or (throw ''
+      No such variant "${variant}" for package iosevka-bin.
+      Valid variants are: ${lib.concatStringsSep ", " validVariants}.
+    '');
+  };
+
+  nativeBuildInputs = [ unzip ];
+
+  phases = [ "unpackPhase" ];
+
+  unpackPhase = ''
     mkdir -p $out/share/fonts
-    unzip -j $downloadedFile \*.ttc -d $out/share/fonts/truetype
+    unzip -d $out/share/fonts/truetype $src
   '';
 
-  sha256 = "1nab49gkpxahwvvw39xcc32q425qkccr7ffmz87jbcdv71qy7pp9";
-
-  meta = with stdenv.lib; {
+  meta = with lib; {
     homepage = "https://be5invis.github.io/Iosevka/";
     downloadPage = "https://github.com/be5invis/Iosevka/releases";
     description = ''
@@ -25,4 +40,6 @@ in fetchzip {
     platforms = platforms.all;
     maintainers = [ maintainers.cstrahan ];
   };
+
+  passthru.updateScript = ./update.sh;
 }

pkgs/data/fonts/iosevka/update.sh

@@ -0,0 +1,28 @@
+#! /usr/bin/env nix-shell
+#! nix-shell -i bash -p curl jq
+
+set -e
+
+release=$(curl -s https://api.github.com/repos/be5invis/Iosevka/releases/latest)
+
+oldVersion=$(nix-instantiate --eval -E 'with import ./. {}; lib.getVersion iosevka-bin' | tr -d '"')
+version=$(echo "$release" | jq -r .tag_name | tr -d v)
+
+if test "$oldVersion" = "$version"; then
+	echo "New version same as old version, nothing to do." >&2
+	exit 0
+fi
+
+file=$(nix-instantiate --eval -A iosevka-bin.meta.position | sed -r 's/^"(.*):[0-9]+"$/\1/')
+sed -i "s/$oldVersion/$version/" "$file"
+
+{
+	echo '# This file was autogenerated. DO NOT EDIT!'
+	echo '{'
+	for asset in $(echo "$release" | jq -r '.assets[].name | select(startswith("ttc"))'); do
+		printf '  %s = "%s";\n' \
+			$(echo "$asset" | sed -r "s/^ttc-(.*)-$version.zip$/\1/") \
+			$(nix-prefetch-url "https://github.com/be5invis/Iosevka/releases/download/v$version/$asset")
+	done
+	echo '}'
+} >$(dirname "$file")/variants.nix

pkgs/data/fonts/iosevka/variants.nix

@@ -0,0 +1,24 @@
+# This file was autogenerated. DO NOT EDIT!
+{
+  iosevka = "0h226f32nwlqnsdc86bwk2wcdl2hsq5q1s2ln6dsf9m7w8ajn0nr";
+  iosevka-aile = "05k3h7n7mkpdsjcxha27vjj503b4129jd90wj8qyk5h0nrgy1rc6";
+  iosevka-curly = "0fxcc99n9ghkdjmfxba9mg4fc0dwlvnnxlmc618jv6s3k2xn7sza";
+  iosevka-curly-slab = "1qgxyw5v91l4cw3mvqzagk9amyy63iqh72bnsz63daxgss3fpsab";
+  iosevka-etoile = "184rjidnjayv5wsrxxxf39mvdcjafdwcvp0h4rfniy9s0ifrwjvf";
+  iosevka-slab = "1cbrv5pyhnvwrdaj8r011igw2yjgzzigd82g1r10d348lk64wja1";
+  iosevka-sparkle = "124jnjzffnfw58b78svw8rzgal10z5nspwc267pvq7q0f2ak1wpp";
+  iosevka-ss01 = "18ckb0ch4za4vgwqz8azx8vhg9v9a922ffbckrbmy8n5bi03dl7w";
+  iosevka-ss02 = "0cwm2jdni5m9z0xagpmq9vvjp3yvin7c7bnavsj15yfvpq8b8qsp";
+  iosevka-ss03 = "1yzbvkr726f8mm024qzy2hdd7nz4kymgjm0cj5208c57bln0byr2";
+  iosevka-ss04 = "1kpz84a1cb39rxc87whw0fh0k9ak2qbcq59hm425da2acf27a648";
+  iosevka-ss05 = "1xnnm96jnw90mhwylsw1ad6m8pr4r1bd02l7g82m5hmr7bc4b7dd";
+  iosevka-ss06 = "1raw01ijiawaqxfmj0m8z8jrb2ns7vzy68lak63mss8j35xzg1l5";
+  iosevka-ss07 = "0bjhjwjif7qw6wyyrzfg2pdvy1b070k053ndmjard6sh1rcln02d";
+  iosevka-ss08 = "1qwgk8riff57np4hlmd0kcl9bx511x9zmnlrjq3ilfn6abdwgm7i";
+  iosevka-ss09 = "0sfnhmcrsv1v7l756hx70y1mrp35fbs6wrsczw4vxfbbaigs767r";
+  iosevka-ss10 = "10n70z7588h8y2z274vjn6hvzc7lg87znibcmkk2brmx2g5bw2wl";
+  iosevka-ss11 = "0mnyd04vdqr8jm3syv6ddrn61f27k91kxkdy86pp34xaac2ipmm0";
+  iosevka-ss12 = "1f8pn2220s6r566b40ncnqrfmfdhnlr0nkvzj9swgvx66jr8mlhj";
+  iosevka-ss13 = "1py5qgfqm9wp9pzcxg83mydvf3r6nhrqi21d0fvmnk04ghk1psd6";
+  iosevka-ss14 = "0z47kqicd26x5v94zy97xyl277v0s6856pbllfn1gv92ax2dg5cy";
+}