From a56a0a5f8314caa21b2e3ce9be8537134ac67bfe Mon Sep 17 00:00:00 2001
From: keroles <keroles971005@gmail.com>
Date: Sat, 27 Jan 2024 22:36:01 +0200
Subject: [PATCH] add stdlib and some comments for battery notify patch:

---
 components/battery.c | 50 ++++++++++++++++++++++++++++++++++++++++++++
 config.def.h         | 11 ++++++++++
 slstatus.h           |  1 +
 3 files changed, 62 insertions(+)

diff --git a/components/battery.c b/components/battery.c
index 1c753f9..f97db41 100644
--- a/components/battery.c
+++ b/components/battery.c
@@ -1,6 +1,7 @@
 /* See LICENSE file for copyright and license details. */
 #include <stdio.h>
 #include <string.h>
+#include <stdlib.h>
 
 #include "../slstatus.h"
 #include "../util.h"
@@ -20,6 +21,12 @@
 	#define POWER_SUPPLY_CURRENT  "/sys/class/power_supply/%s/current_now"
 	#define POWER_SUPPLY_POWER    "/sys/class/power_supply/%s/power_now"
 
+	const char notify_cmd[] = "notify-send";
+	const char battery_str[] = "Battery";
+	int last_notified_level = 0;
+
+	extern const int notifiable_levels[];
+
 	static const char *
 	pick(const char *bat, const char *f1, const char *f2, char *path,
 	     size_t length)
@@ -49,6 +56,49 @@
 		return bprintf("%d", cap_perc);
 	}
 
+	void battery_notify(const char *bat)
+{
+	int cap_perc;
+	char state[12];
+	char path[PATH_MAX];
+
+	if (esnprintf(path, sizeof(path), POWER_SUPPLY_CAPACITY, bat) < 0 || pscanf(path, "%d", &cap_perc) != 1)
+		return;
+
+	if (esnprintf(path, sizeof(path), POWER_SUPPLY_STATUS, bat) < 0 || pscanf(path, "%12[a-zA-Z ]", &state) != 1)
+		return;
+
+	if (strcmp("Charging", state) == 0)
+	{
+		last_notified_level = 0;
+
+		return;
+	}
+
+	if (strcmp("Discharging", state) != 0)
+		return;
+
+	size_t i;
+	const int size = sizeof(*notifiable_levels);
+	char cmd[28];
+
+	for (i = 0; i < size; i++)
+	{
+		if (notifiable_levels[i] != cap_perc)
+			continue;
+
+		if (notifiable_levels[i] != last_notified_level)
+		{
+			last_notified_level = notifiable_levels[i];
+
+			snprintf(cmd, 100, "%s %s %d%%", notify_cmd, battery_str, cap_perc);
+			system(cmd);
+
+			break;
+		}
+	}
+}
+
 	const char *
 	battery_state(const char *bat)
 	{
diff --git a/config.def.h b/config.def.h
index d805331..35d5aa0 100644
--- a/config.def.h
+++ b/config.def.h
@@ -9,11 +9,20 @@ static const char unknown_str[] = "n/a";
 /* maximum output string length */
 #define MAXLEN 2048
 
+/* battery levels to notify - add any levels you want to receive notification for (in percent) */
+const int notifiable_levels[] = {
+    20,
+    10,
+    5,
+};
+
 /*
  * function            description                     argument (example)
  *
  * battery_perc        battery percentage              battery name (BAT0)
  *                                                     NULL on OpenBSD/FreeBSD
+ * battery_notify      linux battery notifications     battery name (BAT0)
+ *                                                     OpenBSD/FreeBSD not supported
  * battery_remaining   battery remaining HH:MM         battery name (BAT0)
  *                                                     NULL on OpenBSD/FreeBSD
  * battery_state       battery charging state          battery name (BAT0)
@@ -66,4 +75,6 @@ static const char unknown_str[] = "n/a";
 static const struct arg args[] = {
 	/* function format          argument */
 	{ datetime, "%s",           "%F %T" },
+        { battery_notify, "",       "BAT0"}, /* There is nothing to print its just a notifications*/
+
 };
diff --git a/slstatus.h b/slstatus.h
index 8ef5874..bb80b23 100644
--- a/slstatus.h
+++ b/slstatus.h
@@ -2,6 +2,7 @@
 
 /* battery */
 const char *battery_perc(const char *);
+void battery_notify(const char *);
 const char *battery_remaining(const char *);
 const char *battery_state(const char *);
 
-- 
2.43.0