run/build: New script; Combines HTML and JS into one HTML file & minifies everything

Author: hoijui

run/build

@@ -0,0 +1,92 @@
+#!/usr/bin/env sh
+# SPDX-FileCopyrightText: 2024 Robin Vobruba <[email protected]>
+# SPDX-License-Identifier: Unlicense
+
+set -eu
+
+script_path="$(readlink -f "$0")"
+script_dir="$(dirname "$script_path")"
+script_name="$(basename "$script_path")"
+
+src_dir="$script_dir/.."
+build_dir="$script_dir/../public"
+js_file="htmlpreview.js"
+js_minified="$build_dir/$js_file"
+index_combined="$build_dir/index_combined.html"
+index_combined_minified="$build_dir/index_combined_minified.html"
+index_final="$build_dir/index.html"
+
+print_help() {
+
+	echo "$script_name - Creates the release version of this tool."
+	echo "This minifies the JavaScript file, inserts it into the HTML (in-line),"
+	echo "and then also minifies the HTML and CSS,"
+	echo "leaving the final result at:"
+	echo "$index_final"
+}
+
+# read command-line args
+i=1
+while [ "$i" -lt "$#" ]
+do
+	arg="$(eval "echo \$$i")"
+
+	case "$arg" in
+		-h|--help)
+			shift "$i"
+			print_help
+			exit 0
+			;;
+		*) # non-/unknown option
+			i=$((i + 1))
+			;;
+	esac
+done
+
+mkdir -p "$build_dir"
+
+# Minify the JavaScript
+npx --no-install \
+	uglify-js \
+		--compress \
+		--output "$js_minified" \
+		-- \
+		"$src_dir/$js_file"
+
+# Inserts the minified JavaScript into a copy of index.html,
+# thus combininig everything into a single file.
+awk '
+	NR==FNR {
+		a[n++] = $0
+		next
+	}
+	/<script src="'"$js_file"'"><\/script>/ {
+		print "<script>"
+		for (i = 0; i < n; ++i) {
+			print a[i]
+		}
+		print "</script>"
+		next
+	}
+	1' \
+	"$js_minified" \
+	"$src_dir/index.html" \
+	> "$index_combined"
+
+# Minifies the HTML and CSS in the above combined file.
+# NOTE While this tool (`@minify-html/node`) is also able to
+#      minify contained JavaScript, it introduces bugs,
+#      which is why we minify it before combining with
+#      `uglify-js` above.
+npx --no-install \
+	@minify-html/node \
+		--output "$index_combined_minified" \
+		--minify-css \
+		--keep-closing-tags \
+		--keep-spaces-between-attributes \
+		--do-not-minify-doctype \
+		"$index_combined"
+
+# Marks the combined & minified version as the one to be used.
+rm -f "$index_final"
+ln -s "$index_combined_minified" "$index_final"