From fc50e669a57fe61938460072882727782157855a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nicol=C3=A1s=20A=2E=20Ortega=20Froysa?=
 <nicolas@ortegas.org>
Date: Thu, 10 Nov 2022 19:10:41 +0100
Subject: [PATCH] Implement concurrent page compilation.

---
 README.md  | 10 ++++++---
 isidore.sh | 60 ++++++++++++++++++++++++++++++++++++++----------------
 2 files changed, 49 insertions(+), 21 deletions(-)

diff --git a/README.md b/README.md
index 8c5d308..a09eaf8 100644
--- a/README.md
+++ b/README.md
@@ -14,9 +14,13 @@ Synopsis: `isidore <command> [options]`
 
 Commands:
 
-- `new [-i] <dir>`: create a new project directory `<dir>`. Use `-i` for
-	interactive mode.
-- `build [-v]`: build the website (default). Use `-v` for verbose.
+- `new [-i] <dir>`: create a new project.
+  - `<dir>`: new project directory.
+  - `-i`: interactive mode.
+- `build [-v] [-j<n>]`: build the website.
+  - `-j<n>`: number of jobs to run concurrently. With `0` it compiles all files
+    at once.
+  - `-v`: run with verbose output.
 - `serve`, `server`: run an HTTP server of the output on port 8080.
 - `clean`: cleans build files.
 - `help`: show help information.
diff --git a/isidore.sh b/isidore.sh
index 8a449d7..071fd95 100755
--- a/isidore.sh
+++ b/isidore.sh
@@ -92,8 +92,8 @@ function print_help()
 	print_usage
 	echo -e "\nCOMMANDS:
   new [-i] <dir>
-    Create a new Isidore project (use interactive mode with '-i')
-  build
+    Create a new Isidore project
+  build [-v] [-j<n>]
     Build the project rooted in the current directory
   serve | server
     Serve a local HTTP server of the output directory on port 8080
@@ -172,6 +172,7 @@ function clean_project()
 #
 # Params:
 #  $1 - Verbose flag
+#  $2 - Maximum number of jobs to run
 ##
 function build_project()
 {
@@ -184,26 +185,40 @@ function build_project()
 		mkdir -p $OUTPUT_DIR/${i:${#SOURCE_DIR}}
 	done
 
+	# number of current jobs
+	local NUM_JOBS="\j"
+
 	for i in $(find site -type f -regextype posix-extended -not -regex '.*\.(cfg|CFG)\.(php|PHP)')
 	do
-		if [[ $i =~ .*\.(php|PHP) ]]
-		then
-			: ${i:${#SOURCE_DIR}}
-			local OUT_FILE="$OUTPUT_DIR/${_: :-4}"
-			if [ $1 == 1 ]
+		while (( $2 != 0 )) && (( ${NUM_JOBS@P} >= $2 ))
+		do
+			wait -n
+		done
+
+		# parallel block
+		(
+			if [[ $i =~ .*\.(php|PHP) ]]
 			then
-				echo "Building $OUT_FILE ..."
+				: ${i:${#SOURCE_DIR}}
+				local OUT_FILE="$OUTPUT_DIR/${_: :-4}"
+				if [ $1 == 1 ]
+				then
+					echo "Building $OUT_FILE ..."
+				fi
+				cat $PROJECT_CONFIG_FILE $i | php > $OUT_FILE
+			else
+				local OUT_FILE="$OUTPUT_DIR/${i:${#SOURCE_DIR}}"
+				if [ $1 == 1 ]
+				then
+					echo "Copying $OUT_FILE ..."
+				fi
+				cp $i $OUT_FILE
 			fi
-			cat $PROJECT_CONFIG_FILE $i | php > $OUT_FILE
-		else
-			local OUT_FILE="$OUTPUT_DIR/${i:${#SOURCE_DIR}}"
-			if [ $1 == 1 ]
-			then
-				echo "Copying $OUT_FILE ..."
-			fi
-			cp $i $OUT_FILE
-		fi
+		) &
 	done
+
+	# wait for jobs to finish
+	wait -n
 }
 
 set_config_vars
@@ -244,6 +259,7 @@ case $1 in
 		new_project $NEW_DIR $INTERACTIVE;;
 	build)
 		VERBOSE=0
+		JOBS=1
 		if [ $# -gt 1 ]
 		then
 			for i in ${@:2}
@@ -251,6 +267,14 @@ case $1 in
 				case $i in
 					-v)
 						VERBOSE=1;;
+					-j*)
+						if ! [[ "$i" =~ ^-j[0-9]+$ ]]
+						then
+							echo "Argument '$i' badly formatted. Should be '-j<n>' where <n> is a number."
+							print_usage
+							exit 1
+						fi
+						JOBS=${i:2};;
 					*)
 						echo "Unknown argument for build '$i'. Use the 'help' subcommand."
 						print_usage
@@ -258,7 +282,7 @@ case $1 in
 				esac
 			done
 		fi
-		build_project $VERBOSE;;
+		build_project $VERBOSE $JOBS;;
 	serve|server)
 		php -S localhost:8080 -t $OUTPUT_DIR/;;
 	clean)