refactor: BatteryInfo structure (consistent layout)

- use tagged enum serialization for BatteryError
- flatten BatteryInfo telemetry with consistent field names and typed error

Software/MainBoard/rust/src/main.rs

@@ -42,8 +42,8 @@ use embassy_sync::once_lock::OnceLock;
 use embassy_time::{Duration, Instant, Timer};
 use esp_hal::rom::ets_delay_us;
 use esp_hal::system::software_reset;
-use esp_println::println;
-use hal::battery::BatteryState;
+use esp_println::{logger, println};
+use hal::battery::{BatteryError, BatteryInfo, BatteryState};
 use log::LogMessage;
 use option_lock::OptionLock;
 use plant_state::PlantState;
@@ -581,16 +581,16 @@ async fn safe_main(spawner: Spawner) -> FatResult<()> {
             board.board_hal.get_config().night_lamp.night_lamp_hour_end,
         );
 
-        match battery_state {
+        match &battery_state {
             BatteryState::Unknown => {
                 light_state.battery_low = false;
             }
             BatteryState::Info(data) => {
-                if data.state_of_charge < board.board_hal.get_config().night_lamp.low_soc_cutoff {
+                if data.soc_pct.is_some_and(|soc| soc < board.board_hal.get_config().night_lamp.low_soc_cutoff as f32) {
                     board.board_hal.get_esp().set_low_voltage_in_cycle();
                     info!("Set low voltage in cycle");
                 }
-                if data.state_of_charge > board.board_hal.get_config().night_lamp.low_soc_restore {
+                if data.soc_pct.is_some_and(|soc| soc > board.board_hal.get_config().night_lamp.low_soc_restore as f32) {
                     board.board_hal.get_esp().clear_low_voltage_in_cycle();
                     info!("Clear low voltage in cycle");
                 }
@@ -639,7 +639,7 @@ async fn safe_main(spawner: Spawner) -> FatResult<()> {
 
     let deep_sleep_duration_minutes: u32 =
         // if battery soc is unknown assume battery has enough change
-        if matches!(battery_state, BatteryState::Info(data) if data.state_of_charge < 10) {
+        if matches!(battery_state, BatteryState::Info(data) if data.soc_pct.is_some_and(|soc| soc < 10.)) {
             let _ = mqtt::publish("/deepsleep", "low Volt 12h").await;
             12 * 60
         } else if is_day {
@@ -984,16 +984,38 @@ async fn publish_mppt_state(
 async fn publish_battery_state(
     board: &mut MutexGuard<'_, CriticalSectionRawMutex, HAL<'static>>,
 ) -> FatResult<()> {
-    let state = board.board_hal.get_battery_monitor().get_state().await;
-    let value = match state {
-        Ok(state) => {
-            let json = serde_json::to_string(&state)?.to_owned();
-            json.to_owned()
-        }
-        Err(_) => "error".to_owned(),
-    };
+    let telemetry = match board
+        .board_hal
+        .get_battery_monitor()
+        .get_state()
+        .await
     {
-        let _ = mqtt::publish("/battery", &*value).await;
+        Ok(BatteryState::Info(info)) => info,
+        Ok(BatteryState::Unknown) => BatteryInfo {
+            voltage_mv: None,
+            avg_current_ma: None,
+            soc_pct: None,
+            soh_pct: None,
+            temperature_c: None,
+            remaining_mah: None,
+            design_mah: None,
+            error: Some(BatteryError::NoBatteryMonitor),
+        },
+        Err(e) => BatteryInfo {
+            voltage_mv: None,
+            avg_current_ma: None,
+            soc_pct: None,
+            soh_pct: None,
+            temperature_c: None,
+            remaining_mah: None,
+            design_mah: None,
+            error: Some(BatteryError::CommunicationError {
+                message: alloc::format!("{:?}", e),
+            }),
+        },
+    };
+    if let Ok(json) = serde_json::to_string(&telemetry) {
+        let _ = mqtt::publish("/battery", &json).await;
     }
     Ok(())
 }