From cea679c1a3592047db4c49b8ac61d917f202a2ff Mon Sep 17 00:00:00 2001
From: Leon Henrik Plickat <leonhenrik.plickat@stud.uni-goettingen.de>
Date: Tue, 15 Jun 2021 11:48:55 +0000
Subject: [PATCH] Add json output mode

---
 wlopm.1 |  6 +++++
 wlopm.c | 75 ++++++++++++++++++++++++++++++++++++++++++---------------
 2 files changed, 61 insertions(+), 20 deletions(-)

diff --git a/wlopm.1 b/wlopm.1
index 1880d24..5a446f2 100644
--- a/wlopm.1
+++ b/wlopm.1
@@ -14,6 +14,12 @@ List outputs and their power modes.
 .P
 .RE
 
+\fBwlopm --json\fR
+.RS 4
+List outputs and their power modes, formatted in JSON.
+.P
+.RE
+
 \fBwlopm on <output-name>\fR
 .RS 4
 Set output power mode to on.
diff --git a/wlopm.c b/wlopm.c
index facec8a..a582c89 100644
--- a/wlopm.c
+++ b/wlopm.c
@@ -33,6 +33,7 @@
 const char usage[] =
 	"Usage:\n"
 	"\twlopm                        List outputs and their power modes.\n"
+	"\twlopm --json                 Format the list as JSON.\n"
 	"\twlopm on     <output-name>   Set output power mode to on.\n"
 	"\twlopm off    <output-name>   Set output power mode to off.\n"
 	"\twlopm toggle <output-name>   Toggle output power mode.\n"
@@ -47,6 +48,7 @@ enum Action
 };
 
 enum Action action = LIST;
+bool json = false;
 char *name = NULL;
 
 struct Output
@@ -159,6 +161,11 @@ static struct Output *output_from_name (const char *str)
 	return NULL;
 }
 
+static char *power_mode_to_string (enum zwlr_output_power_v1_mode mode)
+{
+	return mode == ZWLR_OUTPUT_POWER_V1_MODE_ON ? "on" : "off";
+}
+
 static void sync_handle_done (void *data, struct wl_callback *wl_callback, uint32_t other_data)
 {
 	wl_callback_destroy(wl_callback);
@@ -205,9 +212,24 @@ static void sync_handle_done (void *data, struct wl_callback *wl_callback, uint3
 		if ( action == LIST )
 		{
 			struct Output *output;
-			wl_list_for_each(output, &outputs, link)
-				fprintf(stdout, "%s %s\n", output->name,
-						output->mode == ZWLR_OUTPUT_POWER_V1_MODE_ON ? "on" : "off");
+			if (json)
+			{
+				fputs("[\n", stdout);
+				uint32_t i = 0, len = (uint32_t)wl_list_length(&outputs);
+				wl_list_for_each(output, &outputs, link)
+				{
+					fprintf(stdout, "  {\n    \"output\": \"%s\",\n    \"power-mode\": \"%s\"\n  }%s\n",
+							output->name,
+							power_mode_to_string(output->mode),
+							i < (len - 1) ? "," : "");
+					i++;
+				}
+				fputs("]\n", stdout);
+			}
+			else
+				wl_list_for_each(output, &outputs, link)
+					fprintf(stdout, "%s %s\n", output->name,
+							power_mode_to_string(output->mode));
 			loop = false;
 		}
 		else
@@ -260,26 +282,39 @@ static void sync_handle_done (void *data, struct wl_callback *wl_callback, uint3
 
 int main(int argc, char *argv[])
 {
-	if ( argc == 3 )
+	switch (argc)
 	{
-		if ( strcmp(argv[1], "on") == 0 )
-			action = ON;
-		else if ( strcmp(argv[1], "off") == 0 )
-			action = OFF;
-		else if ( strcmp(argv[1], "toggle") == 0 )
-			action = TOGGLE;
-		else
-		{
+		case 1:
+			break;
+
+		case 2:
+			if ( strcmp(argv[1], "--json") == 0 )
+				json = true;
+			else
+			{
+				fputs(usage, stderr);
+				return EXIT_FAILURE;
+			}
+			break;
+
+		case 3:
+			if ( strcmp(argv[1], "on") == 0 )
+				action = ON;
+			else if ( strcmp(argv[1], "off") == 0 )
+				action = OFF;
+			else if ( strcmp(argv[1], "toggle") == 0 )
+				action = TOGGLE;
+			else
+			{
+				fputs(usage, stderr);
+				return EXIT_FAILURE;
+			}
+			name = strdup(argv[2]);
+			break;
+
+		default:
 			fputs(usage, stderr);
 			return EXIT_FAILURE;
-		}
-
-		name = strdup(argv[2]);
-	}
-	else if ( argc != 1 )
-	{
-		fputs(usage, stderr);
-		return EXIT_FAILURE;
 	}
 
 	/* We query the display name here instead of letting wl_display_connect()