battery: simplify file permission check and improve threshold inheritance

src/battery.rs

@@ -168,10 +168,7 @@ fn path_exists_and_writable(path: &Path) -> bool {
     }
 
     // Try to open the file with write access to verify write permission
-    match fs::OpenOptions::new().write(true).open(path) {
+    fs::OpenOptions::new().write(true).open(path).is_ok()
-        Ok(_) => true,
-        Err(_) => false,
-    }
 }
 
 /// Identifies if a battery supports threshold control and which pattern it uses

src/config/load.rs

@@ -84,14 +84,17 @@ fn load_and_parse_config(path: &Path) -> Result<AppConfig, ConfigError> {
     let mut charger_profile = toml_app_config.charger.clone();
     let mut battery_profile = toml_app_config.battery.clone();
 
-    // If profile-specific battery thresholds are not set, inherit from global config
+    // Clone global battery_charge_thresholds once if it exists
-    if charger_profile.battery_charge_thresholds.is_none() {
+    if let Some(global_thresholds) = toml_app_config.battery_charge_thresholds {
-        charger_profile.battery_charge_thresholds =
+        // Apply to charger profile if not already set
-            toml_app_config.battery_charge_thresholds.clone();
+        if charger_profile.battery_charge_thresholds.is_none() {
-    }
+            charger_profile.battery_charge_thresholds = Some(global_thresholds.clone());
+        }
 
-    if battery_profile.battery_charge_thresholds.is_none() {
+        // Apply to battery profile if not already set
-        battery_profile.battery_charge_thresholds = toml_app_config.battery_charge_thresholds;
+        if battery_profile.battery_charge_thresholds.is_none() {
+            battery_profile.battery_charge_thresholds = Some(global_thresholds);
+        }
     }
 
     // Convert AppConfigToml to AppConfig

src/cpu.rs

@@ -257,12 +257,10 @@ fn validate_epb_value(epb: &str) -> Result<()> {
     if let Ok(value) = epb.parse::<u8>() {
         if value <= 15 {
             return Ok(());
-        } else {
-            return Err(ControlError::InvalidValueError(format!(
-                "EPB numeric value must be between 0 and 15, got {}",
-                value
-            )));
         }
+        return Err(ControlError::InvalidValueError(format!(
+            "EPB numeric value must be between 0 and 15, got {value}"
+        )));
     }
 
     // If not a number, check if it's a recognized string value

src/main.rs

@@ -396,7 +396,11 @@ fn main() {
             // Get available platform profiles and validate early if possible
             match cpu::get_platform_profiles() {
                 Ok(available_profiles) => {
-                    if !available_profiles.contains(&profile) {
+                    if available_profiles.contains(&profile) {
+                        info!("Setting platform profile to '{profile}'");
+                        cpu::set_platform_profile(&profile)
+                            .map_err(|e| Box::new(e) as Box<dyn std::error::Error>)
+                    } else {
                         error!(
                             "Invalid platform profile: '{}'. Available profiles: {}",
                             profile,
@@ -407,10 +411,6 @@ fn main() {
                             profile,
                             available_profiles.join(", ")
                         ))) as Box<dyn std::error::Error>)
-                    } else {
-                        info!("Setting platform profile to '{}'", profile);
-                        cpu::set_platform_profile(&profile)
-                            .map_err(|e| Box::new(e) as Box<dyn std::error::Error>)
                     }
                 }
                 Err(_) => {