feat: add sensor combine mode with Min, Max, and Avg options, update web UI and configuration for multi-sensor support

Software/MainBoard/rust/src/config.rs

@@ -112,6 +112,19 @@ pub struct PlantControllerConfig {
     pub timezone: Option<String>,
 }
 
+#[derive(Serialize, Deserialize, Clone, Debug, PartialEq)]
+pub enum SensorCombineMode {
+    Min,
+    Max,
+    Avg,
+}
+
+impl Default for SensorCombineMode {
+    fn default() -> Self {
+        SensorCombineMode::Avg
+    }
+}
+
 #[derive(Serialize, Deserialize, Clone, Debug, PartialEq)]
 #[serde(default)]
 pub struct PlantConfig {
@@ -133,6 +146,7 @@ pub struct PlantConfig {
     pub ignore_current_error: bool,
     pub fertilizer_s: u16,
     pub fertilizer_cooldown_min: u16,
+    pub sensor_combine_mode: SensorCombineMode,
 }
 
 impl Default for PlantConfig {
@@ -156,6 +170,7 @@ impl Default for PlantConfig {
             ignore_current_error: true,
             fertilizer_s: 0,
             fertilizer_cooldown_min: 1440, // 1 day default
+            sensor_combine_mode: SensorCombineMode::Avg,
         }
     }
 }

Software/MainBoard/rust/src/plant_state.rs

@@ -3,10 +3,7 @@ use crate::{config::PlantConfig, hal::HAL, in_time_range};
 use chrono::{DateTime, TimeDelta, Utc};
 use chrono_tz::Tz;
 use serde::{Deserialize, Serialize};
-
+use crate::config::SensorCombineMode;
-// Embedded environments may not have floating-point math functions.
-// For no_std with k=0.5 (square root), we use Newton's method approximation.
-// Formula: sqrt(t) ≈ iterative refinement for better wet-range discrimination.
 
 const MOIST_SENSOR_MAX_FREQUENCY: f32 = 160000.; // 160kHz -> very wet
 const MOIST_SENSOR_MIN_FREQUENCY: f32 = 400.; // this is really, really dry, think like cactus levels
@@ -113,8 +110,8 @@ pub struct PlantState {
     pub sensor_a_firmware_build_minutes: Option<u32>,
     /// Last known firmware build timestamp for sensor B.
     pub sensor_b_firmware_build_minutes: Option<u32>,
-    /// Last time fertilizer was applied (Unix timestamp in seconds).
+    /// Last time fertilizer was applied.
-    pub last_fertilizer_time: i64,
+    pub last_fertilizer_time: Option<DateTime<Utc>>,
 }
 
 /// Map sensor frequency to moisture percentage using inverse power-law scaling (quadratic).
@@ -228,8 +225,12 @@ impl PlantState {
 
         let previous_pump = board.board_hal.get_esp().last_pump_time(plant_id);
         let consecutive_pump_count = board.board_hal.get_esp().consecutive_pump_count(plant_id);
-        let last_fertilizer_time = board.board_hal.get_esp().last_fertilizer_time(plant_id);
+        let last_fertilizer_timestamp = board.board_hal.get_esp().last_fertilizer_time(plant_id);
         let (a_builds, b_builds) = board.board_hal.get_sensor_build_minutes();
+        
+        let last_fertilizer_time = DateTime::from_timestamp_millis(last_fertilizer_timestamp);
+        
+        // Create plant state first, then check for warnings
         let state = Self {
             sensor_a,
             sensor_b,
@@ -242,7 +243,17 @@ impl PlantState {
             sensor_b_firmware_build_minutes: b_builds[plant_id],
             last_fertilizer_time,
         };
-        if state.is_err() {
+        
+        // Check for sensor warning condition (expected 2 sensors, only 1 responding)
+        let has_a = state.sensor_a.moisture_percent().is_some() && state.sensor_a.is_err().is_none();
+        let has_b = state.sensor_b.moisture_percent().is_some() && state.sensor_b.is_err().is_none();
+        
+        // Check if we expected two sensors but only got one
+        let has_sensor_warning = expected_a && expected_b && ((has_a && !has_b) || (!has_a && has_b));
+        
+        // Set fault LED for both errors AND sensor warnings
+        let has_issue = state.is_err() || has_sensor_warning;
+        if has_issue {
             let _ = board.board_hal.fault(plant_id, true).await;
         }
         state
@@ -265,27 +276,36 @@ impl PlantState {
         self.sensor_a.is_err().is_some() || self.sensor_b.is_err().is_some()
     }
 
-    pub fn plant_moisture(
+    /// Get combined moisture value with configurable combination mode and sensor warning.
+    /// 
+    /// Returns:
+    /// - Combined moisture percentage (or None if no valid readings)
+    /// - Tuple of errors from sensor A and B
+    /// - Sensor warning indicating if warning LED should be lit (MissingSecondSensor)
+    pub fn plant_moisture_with_warning(
         &self,
-    ) -> (
+        plant_conf: &PlantConfig,
-        Option<f32>,
+    ) -> Option<f32>
-        (Option<&MoistureSensorError>, Option<&MoistureSensorError>),
+    {
-    ) {
+        let moisture = match (
-        match (
             self.sensor_a.moisture_percent(),
             self.sensor_b.moisture_percent(),
         ) {
             (Some(moisture_a), Some(moisture_b)) => {
-                (Some((moisture_a + moisture_b) / 2.), (None, None))
+                match plant_conf.sensor_combine_mode {
+                    SensorCombineMode::Min => Some(moisture_a.min(moisture_b)),
+                    SensorCombineMode::Max => Some(moisture_a.max(moisture_b)),
+                    SensorCombineMode::Avg => Some((moisture_a + moisture_b) / 2.0),
+                }
             }
-            (Some(moisture_percent), _) => {
+            (Some(moisture), _) => Some(moisture),
-                (Some(moisture_percent), (None, self.sensor_b.is_err()))
+            (_, Some(moisture)) => Some(moisture),
-            }
+            _ => None,
-            (_, Some(moisture_percent)) => {
+        };
-                (Some(moisture_percent), (self.sensor_a.is_err(), None))
+        
-            }
+
-            _ => (None, (self.sensor_a.is_err(), self.sensor_b.is_err())),
+            moisture
-        }
+
     }
 
     pub fn needs_to_be_watered(
@@ -296,7 +316,7 @@ impl PlantState {
         match plant_conf.mode {
             PlantWateringMode::Off => false,
             PlantWateringMode::TargetMoisture => {
-                let (moisture_percent, _) = self.plant_moisture();
+                let moisture_percent = self.plant_moisture_with_warning(plant_conf);
                 if let Some(moisture_percent) = moisture_percent {
                     if self.pump_in_timeout(plant_conf, current_time) {
                         false
@@ -327,7 +347,7 @@ impl PlantState {
         plant_conf: &PlantConfig,
         current_time: &DateTime<Tz>,
     ) -> PlantInfo {
-        let (moisture_pct, _) = self.plant_moisture();
+        let moisture_pct = self.plant_moisture_with_warning(plant_conf);
         PlantInfo {
             moisture_pct,
             sensor_a: Self::sensor_to_telemetry(&self.sensor_a),
@@ -365,9 +385,25 @@ impl PlantState {
             } else {
                 None
             },
+            last_fertilizer: self.last_fertilizer_time.map(|t| t.with_timezone(&current_time.timezone())),
+            next_fertilizer: if matches!(
+                plant_conf.mode,
+                PlantWateringMode::TimerOnly
+                    | PlantWateringMode::TargetMoisture
+                    | PlantWateringMode::MinMoisture
+            ) {
+                self.last_fertilizer_time.and_then(|last_fert| {
+                    // Convert to Tz for calculation, then back
+                    let tz_last_fert = last_fert.with_timezone(&current_time.timezone());
+                    tz_last_fert
+                        .checked_add_signed(TimeDelta::minutes(plant_conf.fertilizer_cooldown_min.into()))
+                        .map(|t| t.with_timezone(&current_time.timezone()))
+                })
+            } else {
+                None
+            },
             sensor_a_firmware_build_minutes: self.sensor_a_firmware_build_minutes,
             sensor_b_firmware_build_minutes: self.sensor_b_firmware_build_minutes,
-            last_fertilizer_time: self.last_fertilizer_time,
         }
     }
 
@@ -423,10 +459,12 @@ pub struct PlantInfo {
     last_pump: Option<DateTime<Tz>>,
     /// next time when pump should activate
     next_pump: Option<DateTime<Tz>>,
+    /// last time when fertilizer was applied
+    last_fertilizer: Option<DateTime<Tz>>,
+    /// next time when fertilizer should be applied
+    next_fertilizer: Option<DateTime<Tz>>,
     /// firmware build timestamp of sensor A (minutes since Unix epoch); None if unknown
     sensor_a_firmware_build_minutes: Option<u32>,
     /// firmware build timestamp of sensor B (minutes since Unix epoch); None if unknown
     sensor_b_firmware_build_minutes: Option<u32>,
-    /// last time when fertilizer was applied
-    last_fertilizer_time: i64,
 }

Software/MainBoard/rust/src_webpack/src/api.ts

@@ -141,6 +141,7 @@ export interface PlantConfig {
     min_pump_current_ma: number,
     max_pump_current_ma: number,
     ignore_current_error: boolean,
+    sensor_combine_mode: string,
 }
 
 export interface PumpTestResult {

Software/MainBoard/rust/src_webpack/src/plant.html

@@ -29,6 +29,9 @@
     .plantSensorEnabledOnly_ ${plantId} {
     }
 
+    .plantBothSensorsOnly_ ${plantId} {
+    }
+
     .plantHidden_ ${plantId} {
         display: none;
     }
@@ -48,6 +51,14 @@
         <div class="plantkey">Sensor B installed:</div>
         <input class="plantcheckbox" id="plant_${plantId}_sensor_b" type="checkbox">
     </div>
+    <div class="flexcontainer plantBothSensorsOnly_${plantId}">
+        <div class="plantkey">Sensor Combine Mode:</div>
+        <select class="plantvalue" id="plant_${plantId}_sensor_combine_mode">
+            <option value="Min">Min</option>
+            <option value="Max">Max</option>
+            <option value="Avg">Average</option>
+        </select>
+    </div>
     <div class="flexcontainer">
         <div class="plantkey">
             Mode:

Software/MainBoard/rust/src_webpack/src/plant.ts

@@ -93,6 +93,7 @@ export class PlantView {
     private readonly pumpHourEnd: HTMLSelectElement;
     private readonly sensorAInstalled: HTMLInputElement;
     private readonly sensorBInstalled: HTMLInputElement;
+    private readonly sensorCombineMode: HTMLSelectElement;
     private readonly mode: HTMLSelectElement;
     private readonly moistureA: HTMLElement;
     private readonly moistureB: HTMLElement;
@@ -236,6 +237,14 @@ export class PlantView {
             controller.configChanged()
         }
 
+        this.sensorCombineMode = document.getElementById("plant_" + plantId + "_sensor_combine_mode") as HTMLSelectElement;
+        this.sensorCombineMode.onchange = function () {
+            controller.configChanged()
+        }
+
+        // Initial visibility update for sensor combine mode
+        this.updateSensorCombineModeState();
+
         this.minPumpCurrentMa = document.getElementById("plant_" + plantId + "_min_pump_current_ma") as HTMLInputElement;
         this.minPumpCurrentMa.onchange = function () {
             controller.configChanged()
@@ -271,6 +280,19 @@ export class PlantView {
         };
     }
 
+    updateSensorCombineModeState() {
+        const bothActive = this.sensorAInstalled.checked && this.sensorBInstalled.checked;
+        const bothOnlyElements = document.getElementsByClassName("plantBothSensorsOnly_" + this.plantId);
+        for (const element of Array.from(bothOnlyElements)) {
+            if (bothActive) {
+                element.classList.remove("plantHidden_" + this.plantId);
+            } else {
+                element.classList.add("plantHidden_" + this.plantId);
+            }
+        }
+        this.sensorCombineMode.disabled = !bothActive;
+    }
+
     updateVisibility(plantConfig: PlantConfig) {
         let sensorOnly = document.getElementsByClassName("plantSensorEnabledOnly_" + this.plantId)
         let pumpOnly = document.getElementsByClassName("plantPumpEnabledOnly_" + this.plantId)
@@ -324,6 +346,9 @@ export class PlantView {
         //         element.classList.add("plantHidden_" + this.plantId)
         //     }
         // }
+
+        // Update sensor combine mode visibility based on whether both sensors are active
+        this.updateSensorCombineModeState();
     }
 
     setTestResult(result: PumpTestResult) {
@@ -354,6 +379,7 @@ export class PlantView {
         this.pumpHourEnd.value = plantConfig.pump_hour_end.toString();
         this.sensorBInstalled.checked = plantConfig.sensor_b;
         this.sensorAInstalled.checked = plantConfig.sensor_a;
+        this.sensorCombineMode.value = plantConfig.sensor_combine_mode || "Min";
         this.maxConsecutivePumpCount.value = plantConfig.max_consecutive_pump_count.toString();
         this.minPumpCurrentMa.value = plantConfig.min_pump_current_ma.toString();
         this.maxPumpCurrentMa.value = plantConfig.max_pump_current_ma.toString();
@@ -383,6 +409,7 @@ export class PlantView {
             pump_hour_end: +this.pumpHourEnd.value,
             sensor_b: this.sensorBInstalled.checked,
             sensor_a: this.sensorAInstalled.checked,
+            sensor_combine_mode: this.sensorCombineMode.value,
             max_consecutive_pump_count: this.maxConsecutivePumpCount.valueAsNumber,
             moisture_sensor_min_frequency: this.moistureSensorMinFrequency.valueAsNumber || null,
             moisture_sensor_max_frequency: this.moistureSensorMaxFrequency.valueAsNumber || null,