From d9282b16cb5ec6a275acde30b76d259385f3d7aa Mon Sep 17 00:00:00 2001
From: Cameron Aaron <cameronaaron@users.noreply.github.com>
Date: Tue, 12 Nov 2024 17:16:50 -0800
Subject: [PATCH] Switch to pmset

Fixes #512
---
 .../services/caffeinateService/index.ts       | 61 +++++++++++++++----
 1 file changed, 50 insertions(+), 11 deletions(-)

diff --git a/packages/server/src/server/services/caffeinateService/index.ts b/packages/server/src/server/services/caffeinateService/index.ts
index 5a3495d4..bd7d520d 100644
--- a/packages/server/src/server/services/caffeinateService/index.ts
+++ b/packages/server/src/server/services/caffeinateService/index.ts
@@ -3,7 +3,7 @@ import { spawn, ChildProcessWithoutNullStreams } from "child_process";
 import { Loggable } from "@server/lib/logging/Loggable";
 
 /**
- * Service that spawns the caffeinate process so that
+ * Service that spawns the pmset process so that
  * the macOS operating system does not sleep until the server
  * exits.
  */
@@ -14,20 +14,26 @@ export class CaffeinateService extends Loggable {
 
     childProc: ChildProcessWithoutNullStreams;
 
+    originalSleepSettings: { displaysleep: string; disksleep: string; sleep: string } = {
+        displaysleep: "",
+        disksleep: "",
+        sleep: ""
+    };
+
     /**
-     * Runs caffeinate until the current process is killed
+     * Runs pmset until the current process is killed
      */
     start() {
         if (this.isCaffeinated) return;
         const myPid = process.pid;
 
+        // Cache existing sleep values
+        this.cacheSleepValues();
+
         // Spawn the child process
-        // -i: Create an assertion to prevent the system from idle sleeping.
-        // -m: Create an assertion to prevent the disk from idle sleeping.
-        // -s: Create an assertion to prevent the system from sleeping
-        // -w: Waits for the process with the specified pid to exit.
-        this.childProc = spawn("caffeinate", ["-i", "-m", "-s", "-w", myPid.toString()], { detached: true });
-        this.log.info(`Spawned Caffeinate with PID: ${this.childProc.pid}`);
+        // Prevent system sleep
+        this.childProc = spawn("pmset", ["-a", "displaysleep", "0", "disksleep", "0", "sleep", "0"], { detached: true });
+        this.log.info(`Spawned pmset with PID: ${this.childProc.pid}`);
         this.isCaffeinated = true;
 
         // Setup listeners
@@ -47,21 +53,54 @@ export class CaffeinateService extends Loggable {
             try {
                 const killed = this.childProc.kill();
                 if (!killed) process.kill(-this.childProc.pid);
-                this.log.debug("Killed caffeinate process");
+                this.log.debug("Killed pmset process");
             } catch (ex: any) {
-                this.log.error(`Failed to kill caffeinate process! ${ex.message}`);
+                this.log.error(`Failed to kill pmset process! ${ex.message}`);
             } finally {
                 this.isCaffeinated = false;
+                // Restore cached sleep values
+                this.restoreSleepValues();
             }
         }
     }
 
     /**
-     * Method to let us know that the caffeinate process has ended
+     * Method to let us know that the pmset process has ended
      *
      * @param _ The message returned by the EventEmitter
      */
     private onClose(msg: any) {
         this.isCaffeinated = false;
     }
+
+    /**
+     * Cache the current sleep values
+     */
+    private cacheSleepValues() {
+        const displaysleep = this.executePmsetCommand("displaysleep");
+        const disksleep = this.executePmsetCommand("disksleep");
+        const sleep = this.executePmsetCommand("sleep");
+
+        this.originalSleepSettings = { displaysleep, disksleep, sleep };
+    }
+
+    /**
+     * Restore the cached sleep values
+     */
+    private restoreSleepValues() {
+        const { displaysleep, disksleep, sleep } = this.originalSleepSettings;
+
+        this.executePmsetCommand("displaysleep", displaysleep);
+        this.executePmsetCommand("disksleep", disksleep);
+        this.executePmsetCommand("sleep", sleep);
+    }
+
+    /**
+     * Execute pmset command
+     */
+    private executePmsetCommand(setting: string, value?: string): string {
+        const args = value ? ["-a", setting, value] : ["-g", setting];
+        const result = spawnSync("pmset", args);
+        return result.stdout.toString().trim();
+    }
 }