Document version 1.2.1 release in VERSION.md

Added version 1.2.1 release notes detailing stability improvements, stack size increase, heap pre-allocation, and unified JSON sensor states.

CHANGELOG.md

@@ -1,4 +1,175 @@
-# EPrices v1.0 – Changelog
+# EPrices – Changelog
+
+## v1.2.1 — 2026-04-07
+
+### ESP32 main task stack size increase
+
+Increased the FreeRTOS main application task stack from the ESP-IDF default
+of 8192 bytes to 16384 bytes. This eliminates the stack overflow scenario
+that most likely caused the spontaneous reboot observed in production on
+2026-04-06, where the FreeRTOS idle task faulted following memory pressure
+during a simultaneous NVS load and HTTP fetch/parse cycle.
+
+The 8 KB cost is well within the ESP32's 320 KB available RAM.
+
+**Changed location in `eprices.yaml`:**
+- `esp32: framework: sdkconfig_options:` — added
+  `CONFIG_ESP_MAIN_TASK_STACK_SIZE: "16384"`
+
+---
+
+### Price vector heap pre-allocation at boot
+
+Pre-allocated capacity for all four price vectors at boot using `.reserve(96)`.
+Previously, each vector started empty and grew incrementally on every NVS load
+and HTTP fetch, triggering repeated heap reallocations and leaving the heap
+fragmented before the first fetch cycle completed.
+
+With capacity reserved upfront, no reallocation occurs during any subsequent
+NVS load or HTTP parse operation. This reduces heap fragmentation and peak
+allocation spikes, particularly during the boot sequence where NVS load and
+the first HTTP fetch can overlap.
+
+**Vectors pre-allocated:**
+- `price_timestamps_today`
+- `price_values_today`
+- `price_timestamps_tomorrow`
+- `price_values_tomorrow`
+
+**Changed location in `eprices.yaml`:**
+- `on_boot:` lambda — added `.reserve(96)` on all four price vectors
+
+---
+
+### Hourly JSON sensor cleared state unified with 15-min sensors
+
+The two hourly JSON text sensors previously published `"[]"` when cleared
+(at midnight bridge and on `clear_today_prices` / `clear_tomorrow_prices`).
+The six 15-minute JSON sensors already published `""` in the same situation.
+All eight JSON sensors now publish `""` when cleared, giving consistent
+behaviour across the full sensor set.
+
+**Affected sensors:**
+- `Today JSON Hourly Prices EUR⁄kWh`
+- `Tomorrow JSON Hourly Prices EUR⁄kWh`
+
+**Changed locations in `eprices.yaml`:**
+- `clear_today_prices` script — `"[]"` → `""`
+- `clear_tomorrow_prices` script — `"[]"` → `""`
+- `midnight_bridge_promotion` script — `"[]"` → `""` (where applicable)
+
+---
+
+## v1.2 — 2026-04-06
+
+### HTTP fetch stuck-flag watchdog
+
+Fixed a reliability issue where an HTTP fetch that stalled at the TCP level
+(connection accepted by the server but data delivery suspended) could hold
+`is_updating_today` or `is_updating_tomorrow` locked at `true` indefinitely.
+While the flag was stuck, all subsequent auto-retry triggers and manual button
+presses were silently blocked.
+
+**Root cause:** The application-level 25 s HTTP timeout does not fire when the
+TCP connection is established but the server stops sending data mid-transfer.
+The socket never goes idle from the OS perspective, so the timeout never
+triggers, and the fetch hangs until the TCP stack eventually resets the
+connection — which can take several minutes.
+
+**Fix:** Added a 120-second watchdog to both the today and tomorrow worker
+loops (`seconds: /10`). If `is_updating_*` has been `true` for more than 120
+seconds, the worker force-clears the flag and sets the status message to
+`"Fetch timeout – will retry"`. The next scheduled retry or manual press then
+proceeds normally.
+
+**New globals:**
+- `is_updating_today_since` (`time_t`) — timestamp when `is_updating_today` was last set to `true`
+- `is_updating_tomorrow_since` (`time_t`) — timestamp when `is_updating_tomorrow` was last set to `true`
+
+Both timestamps are set immediately alongside `is_updating_* = true` inside
+`smart_price_update` and `smart_tomorrow_price_update`.
+
+**Changed locations in `eprices.yaml`:**
+- `globals:` — added `is_updating_today_since` and `is_updating_tomorrow_since`
+- `smart_price_update` script — added `id(is_updating_today_since) = ...` alongside flag set
+- `smart_tomorrow_price_update` script — added `id(is_updating_tomorrow_since) = ...` alongside flag set
+- Today worker (`seconds: /10`) — watchdog block added before existing worker logic
+- Tomorrow worker (`seconds: /10`) — watchdog block added before existing worker logic
+
+---
+
+### Tomorrow auto-retry attempt counter fix
+
+Fixed a bug where `tomorrow_retry_count` was not incremented in the 13:55 and
+14:55–19:55 hourly retry triggers. Those triggers called
+`smart_tomorrow_price_update` directly without incrementing the counter first,
+causing the `Tomorrow API Fetch Attempts` diagnostic sensor to undercount
+attempts after the first one at 13:25.
+
+**Changed locations in `eprices.yaml`:**
+- 13:55 trigger — added `id(tomorrow_retry_count)++` before `.execute()`
+- 14:55–19:55 hourly trigger — added `id(tomorrow_retry_count)++` before `.execute()`
+
+---
+
+### Status message improvements
+
+Two status message strings that contained a hardcoded time reference have been
+corrected. Both were misleading after a device reboot in the afternoon or a
+manual `clear_tomorrow_prices` call outside the normal fetch window.
+
+| Location | Old value | New value |
+|---|---|---|
+| `tomorrow_update_status_message` global `initial_value` | `"Waiting for 13:20"` | `"No data yet"` |
+| `clear_tomorrow_prices` script end | `"Cleared – awaiting next 13:20 window"` | `"Cleared – awaiting fetch window"` |
+
+---
+
+## v1.1 — 2026-04-06
+
+### Negative price provider fee support
+
+Added a separate provider fee multiplier for negative spot prices, configurable
+via `secrets.yaml`. This correctly models contracts where the provider fee
+structure differs between positive and negative market prices.
+
+**New secret key:**
+
+```yaml
+eprices_neg_prov_fee: "0.30"
+```
+
+**New global:** `neg_prov_fee` (type: `double`)
+
+**Price calculation is now:**
+
+| Market price | Formula |
+|---|---|
+| Positive (`raw_mwh >= 0`) | `(raw / 1000) × (1 + prov_fee) × (1 + vat_rate)` |
+| Negative (`raw_mwh < 0`) | `(raw / 1000) × (1 - neg_prov_fee) × (1 + vat_rate)` |
+
+**Key values for `eprices_neg_prov_fee`:**
+
+| Value | Meaning |
+|---|---|
+| `"0.30"` | Provider keeps 30%, pays you 70% of negative price |
+| `"0.00"` | Provider passes full negative price to you (no fee) |
+
+**Switch point:** raw API price (`raw_mwh`) before any multiplier is applied.
+
+**VAT:** applied symmetrically to both positive and negative prices, consistent
+with net billing models where VAT is calculated on the monthly net sum
+(mathematically equivalent due to VAT being a linear multiplier).
+
+**Changed files:** `eprices.yaml`, `secrets.yaml`
+
+**Changed locations in `eprices.yaml`:**
+- `substitutions:` — added `neg_prov_fee_value`
+- `globals:` — added `neg_prov_fee`
+- `parse_energy_charts_today_script` — `MULT` split into `MULT_POS` / `MULT_NEG`
+- `parse_energy_charts_tomorrow_script` — `MULT` split into `MULT_POS` / `MULT_NEG`
+
+---
 
 ## v1.0 — 2026-04-05
 
@@ -68,10 +239,10 @@ eprices_vat_rate          # e.g. "0.22"  (VAT rate as decimal multiplier)
 
 | Name | Entity ID | Notes |
 |---|---|---|
-| Today JSON Hourly Prices EUR⁄kWh | `sensor.eprices_today_json_hourly_prices_eur_kwh` | JSON array, 24 values |
-| Today JSON 15-Min Prices EUR⁄kWh (P1 00:00-07:45) | `sensor.eprices_today_json_15_min_prices_eur_kwh_p1_00_00_07_45` | JSON array, 32 values |
-| Today JSON 15-Min Prices EUR⁄kWh (P2 08:00-15:45) | `sensor.eprices_today_json_15_min_prices_eur_kwh_p2_08_00_15_45` | JSON array, 32 values |
-| Today JSON 15-Min Prices EUR⁄kWh (P3 16:00-23:45) | `sensor.eprices_today_json_15_min_prices_eur_kwh_p3_16_00_23_45` | JSON array, 32 values |
+| Today JSON Hourly Prices EUR⁄kWh | `sensor.eprices_today_json_hourly_prices_eur_kwh` | JSON array, 24 values; `""` when no data |
+| Today JSON 15-Min Prices EUR⁄kWh (P1 00:00-07:45) | `sensor.eprices_today_json_15_min_prices_eur_kwh_p1_00_00_07_45` | JSON array, 32 values; `""` when no data |
+| Today JSON 15-Min Prices EUR⁄kWh (P2 08:00-15:45) | `sensor.eprices_today_json_15_min_prices_eur_kwh_p2_08_00_15_45` | JSON array, 32 values; `""` when no data |
+| Today JSON 15-Min Prices EUR⁄kWh (P3 16:00-23:45) | `sensor.eprices_today_json_15_min_prices_eur_kwh_p3_16_00_23_45` | JSON array, 32 values; `""` when no data |
 | Today Highest Price Time | `sensor.eprices_today_highest_price_time` | HH:MM |
 | Today Lowest Price Time | `sensor.eprices_today_lowest_price_time` | HH:MM |
 | Today Highest Hourly Price Time | `sensor.eprices_today_highest_hourly_price_time` | HH:00 |
@@ -83,10 +254,10 @@ eprices_vat_rate          # e.g. "0.22"  (VAT rate as decimal multiplier)
 | Today Price Update Status Message | `sensor.eprices_today_price_update_status_message` | Detailed status string; diagnostic |
 | Today API Fetch Attempts | `sensor.eprices_today_api_fetch_attempts` | HTTP fetch count; resets at midnight; diagnostic |
 | Today Entry Count | `sensor.eprices_today_entry_count` | Number of stored price points; diagnostic |
-| Tomorrow JSON Hourly Prices EUR⁄kWh | `sensor.eprices_tomorrow_json_hourly_prices_eur_kwh` | JSON array, 24 values |
-| Tomorrow JSON 15-Min Prices EUR⁄kWh (P1 00:00-07:45) | `sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p1_00_00_07_45` | JSON array, 32 values |
-| Tomorrow JSON 15-Min Prices EUR⁄kWh (P2 08:00-15:45) | `sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p2_08_00_15_45` | JSON array, 32 values |
-| Tomorrow JSON 15-Min Prices EUR⁄kWh (P3 16:00-23:45) | `sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p3_16_00_23_45` | JSON array, 32 values |
+| Tomorrow JSON Hourly Prices EUR⁄kWh | `sensor.eprices_tomorrow_json_hourly_prices_eur_kwh` | JSON array, 24 values; `""` when no data |
+| Tomorrow JSON 15-Min Prices EUR⁄kWh (P1 00:00-07:45) | `sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p1_00_00_07_45` | JSON array, 32 values; `""` when no data |
+| Tomorrow JSON 15-Min Prices EUR⁄kWh (P2 08:00-15:45) | `sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p2_08_00_15_45` | JSON array, 32 values; `""` when no data |
+| Tomorrow JSON 15-Min Prices EUR⁄kWh (P3 16:00-23:45) | `sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p3_16_00_23_45` | JSON array, 32 values; `""` when no data |
 | Tomorrow Highest Price Time | `sensor.eprices_tomorrow_highest_price_time` | HH:MM |
 | Tomorrow Lowest Price Time | `sensor.eprices_tomorrow_lowest_price_time` | HH:MM |
 | Tomorrow Highest Hourly Price Time | `sensor.eprices_tomorrow_highest_hourly_price_time` | HH:00 |
@@ -126,4 +297,5 @@ eprices_vat_rate          # e.g. "0.22"  (VAT rate as decimal multiplier)
 - **Tomorrow Data Loaded Time** shows `Outside fetch window` when device boots before 13:20
 - **API fetch times** reset to `Never` at midnight bridge and on `clear_tomorrow_prices`
 - **API fetch attempt counters** reset to `0` at midnight and publish `0` immediately on boot
-- **Uptime** displayed as human-readable string: `45 s` / `5 min` / `3 h 22 min` / `12 d 4 h` / `4 months 12 d`
+- **Uptime** displayed as human-readable string: `45 s` / `5 min` / `3 h 22 min` / `12 d 4 h` / `4 months 12 d`
+- **JSON sensors** publish `""` (empty string) when no data is available — all eight JSON sensors behave consistently

ENTSO-E-PRICES-MIGRATION.md

@@ -85,96 +85,114 @@ The goal of EPrices was to:
 | Manual force update | Button | Button (unchanged) |
 | Midnight bridge | External HA automation at 00:00 | On-device `on_time: 00:00:00` |
 
+---
+
 ### Sensor naming
 
 All sensors were renamed with a systematic **Today / Tomorrow** prefix.
 The words "electricity" and "energy" were removed from all sensor names.
 "Next Day" was replaced with "Tomorrow" throughout.
 
+> **Note on entity ID slugs:** HA derives entity IDs by lower-casing the
+> sensor name and replacing spaces and special characters with underscores.
+> The `⁄` character in JSON sensor names may have been rendered differently
+> by older ESPHome versions — verify those specific IDs against your actual
+> HA instance if needed.
+
+---
+
 #### Numeric sensors
 
-| entso-e-prices v4.3.1 name | EPrices v1.0 name |
-|---|---|
-| `Current Electricity Price` | `Today Current Price` |
-| `Next Electricity Price` | `Today Next Price` |
-| `Average Electricity Price Today` | `Today Average Price` |
-| `Highest Electricity Price Today` | `Today Highest Price` |
-| `Lowest Electricity Price Today` | `Today Lowest Price` |
-| `Current Hourly Electricity Price` | `Today Current Hourly Price` |
-| `Next Hourly Electricity Price` | `Today Next Hourly Price` |
-| `Highest Hourly Electricity Price Today` | `Today Highest Hourly Price` |
-| `Lowest Hourly Electricity Price Today` | `Today Lowest Hourly Price` |
-| `Current Max Hourly Price Percentage` | `Today Current Max Hourly Price Percentage` |
-| `Daily Price Update Attempts` | `Today API Fetch Attempts` *(moved to text_sensor)* |
-| `Today Entry Count` | `Today Entry Count` *(moved to text_sensor)* |
-| `Next Day Current Electricity Price` | `Tomorrow Current Price` |
-| `Next Day Next Electricity Price` | `Tomorrow Next Price` |
-| `Average Electricity Price Tomorrow` | `Tomorrow Average Price` |
-| `Highest Electricity Price Tomorrow` | `Tomorrow Highest Price` |
-| `Lowest Electricity Price Tomorrow` | `Tomorrow Lowest Price` |
-| `Current Hourly Electricity Price Tomorrow` | `Tomorrow Current Hourly Price` |
-| `Next Hourly Electricity Price Tomorrow` | `Tomorrow Next Hourly Price` |
-| `Highest Hourly Electricity Price Tomorrow` | `Tomorrow Highest Hourly Price` |
-| `Lowest Hourly Electricity Price Tomorrow` | `Tomorrow Lowest Hourly Price` |
-| `Next Day Current Max Hourly Price Percentage` | `Tomorrow Current Max Hourly Price Percentage` |
-| `Next Day Price Update Attempts` | `Tomorrow API Fetch Attempts` *(moved to text_sensor)* |
-| `Tomorrow Entry Count` | `Tomorrow Entry Count` *(moved to text_sensor)* |
+| entso-e-prices v4.3.1 name | v4.3.1 entity ID | EPrices v1.2 name | EPrices v1.2 entity ID |
+|---|---|---|---|
+| `Current Electricity Price` | `sensor.entso_e_prices_current_electricity_price` | `Today Current Price` | `sensor.eprices_today_current_price` |
+| `Next Electricity Price` | `sensor.entso_e_prices_next_electricity_price` | `Today Next Price` | `sensor.eprices_today_next_price` |
+| `Average Electricity Price Today` | `sensor.entso_e_prices_average_electricity_price_today` | `Today Average Price` | `sensor.eprices_today_average_price` |
+| `Highest Electricity Price Today` | `sensor.entso_e_prices_highest_electricity_price_today` | `Today Highest Price` | `sensor.eprices_today_highest_price` |
+| `Lowest Electricity Price Today` | `sensor.entso_e_prices_lowest_electricity_price_today` | `Today Lowest Price` | `sensor.eprices_today_lowest_price` |
+| `Current Hourly Electricity Price` | `sensor.entso_e_prices_current_hourly_electricity_price` | `Today Current Hourly Price` | `sensor.eprices_today_current_hourly_price` |
+| `Next Hourly Electricity Price` | `sensor.entso_e_prices_next_hourly_electricity_price` | `Today Next Hourly Price` | `sensor.eprices_today_next_hourly_price` |
+| `Highest Hourly Electricity Price Today` | `sensor.entso_e_prices_highest_hourly_electricity_price_today` | `Today Highest Hourly Price` | `sensor.eprices_today_highest_hourly_price` |
+| `Lowest Hourly Electricity Price Today` | `sensor.entso_e_prices_lowest_hourly_electricity_price_today` | `Today Lowest Hourly Price` | `sensor.eprices_today_lowest_hourly_price` |
+| `Current Max Hourly Price Percentage` | `sensor.entso_e_prices_current_max_hourly_price_percentage` | `Today Current Max Hourly Price Percentage` | `sensor.eprices_today_current_max_hourly_price_percentage` |
+| `Daily Price Update Attempts` | `sensor.entso_e_prices_daily_price_update_attempts` | `Today API Fetch Attempts` *(moved to text_sensor)* | `sensor.eprices_today_api_fetch_attempts` |
+| `Today Entry Count` | `sensor.entso_e_prices_today_entry_count` | `Today Entry Count` *(moved to text_sensor)* | `sensor.eprices_today_entry_count` |
+| `Next Day Current Electricity Price` | `sensor.entso_e_prices_next_day_current_electricity_price` | `Tomorrow Current Price` | `sensor.eprices_tomorrow_current_price` |
+| `Next Day Next Electricity Price` | `sensor.entso_e_prices_next_day_next_electricity_price` | `Tomorrow Next Price` | `sensor.eprices_tomorrow_next_price` |
+| `Average Electricity Price Tomorrow` | `sensor.entso_e_prices_average_electricity_price_tomorrow` | `Tomorrow Average Price` | `sensor.eprices_tomorrow_average_price` |
+| `Highest Electricity Price Tomorrow` | `sensor.entso_e_prices_highest_electricity_price_tomorrow` | `Tomorrow Highest Price` | `sensor.eprices_tomorrow_highest_price` |
+| `Lowest Electricity Price Tomorrow` | `sensor.entso_e_prices_lowest_electricity_price_tomorrow` | `Tomorrow Lowest Price` | `sensor.eprices_tomorrow_lowest_price` |
+| `Current Hourly Electricity Price Tomorrow` | `sensor.entso_e_prices_current_hourly_electricity_price_tomorrow` | `Tomorrow Current Hourly Price` | `sensor.eprices_tomorrow_current_hourly_price` |
+| `Next Hourly Electricity Price Tomorrow` | `sensor.entso_e_prices_next_hourly_electricity_price_tomorrow` | `Tomorrow Next Hourly Price` | `sensor.eprices_tomorrow_next_hourly_price` |
+| `Highest Hourly Electricity Price Tomorrow` | `sensor.entso_e_prices_highest_hourly_electricity_price_tomorrow` | `Tomorrow Highest Hourly Price` | `sensor.eprices_tomorrow_highest_hourly_price` |
+| `Lowest Hourly Electricity Price Tomorrow` | `sensor.entso_e_prices_lowest_hourly_electricity_price_tomorrow` | `Tomorrow Lowest Hourly Price` | `sensor.eprices_tomorrow_lowest_hourly_price` |
+| `Next Day Current Max Hourly Price Percentage` | `sensor.entso_e_prices_next_day_current_max_hourly_price_percentage` | `Tomorrow Current Max Hourly Price Percentage` | `sensor.eprices_tomorrow_current_max_hourly_price_percentage` |
+| `Next Day Price Update Attempts` | `sensor.entso_e_prices_next_day_price_update_attempts` | `Tomorrow API Fetch Attempts` *(moved to text_sensor)* | `sensor.eprices_tomorrow_api_fetch_attempts` |
+| `Tomorrow Entry Count` | `sensor.entso_e_prices_tomorrow_entry_count` | `Tomorrow Entry Count` *(moved to text_sensor)* | `sensor.eprices_tomorrow_entry_count` |
+
+---
 
 #### Text sensors
 
-| entso-e-prices v4.3.1 name | EPrices v1.0 name |
-|---|---|
-| `ENTSO-E Hourly Prices EUR⁄kWh JSON` | `Today JSON Hourly Prices EUR⁄kWh` |
-| `ENTSO-E 15-Min Prices EUR⁄kWh JSON (P1 00:00-07:45)` | `Today JSON 15-Min Prices EUR⁄kWh (P1 00:00-07:45)` |
-| `ENTSO-E 15-Min Prices EUR⁄kWh JSON (P2 08:00-15:45)` | `Today JSON 15-Min Prices EUR⁄kWh (P2 08:00-15:45)` |
-| `ENTSO-E 15-Min Prices EUR⁄kWh JSON (P3 16:00-23:45)` | `Today JSON 15-Min Prices EUR⁄kWh (P3 16:00-23:45)` |
-| `Time Of Highest Energy Price Today` | `Today Highest Price Time` |
-| `Time Of Lowest Energy Price Today` | `Today Lowest Price Time` |
-| `Time Of Highest Hourly Energy Price Today` | `Today Highest Hourly Price Time` |
-| `Time Of Lowest Hourly Energy Price Today` | `Today Lowest Hourly Price Time` |
-| `Price Update Status` | `Today Price Update Status` |
-| `Last Price Update Time` | `Today Data Loaded Time` |
-| `Price Update Status Message` | `Today Price Update Status Message` |
-| `Current Price Status` | `Today Current Price Status` |
-| `ENTSO-E Next Day Hourly Prices EUR⁄kWh JSON` | `Tomorrow JSON Hourly Prices EUR⁄kWh` |
-| `ENTSO-E Next Day 15-Min Prices EUR⁄kWh JSON (P1 00:00-07:45)` | `Tomorrow JSON 15-Min Prices EUR⁄kWh (P1 00:00-07:45)` |
-| `ENTSO-E Next Day 15-Min Prices EUR⁄kWh JSON (P2 08:00-15:45)` | `Tomorrow JSON 15-Min Prices EUR⁄kWh (P2 08:00-15:45)` |
-| `ENTSO-E Next Day 15-Min Prices EUR⁄kWh JSON (P3 16:00-23:45)` | `Tomorrow JSON 15-Min Prices EUR⁄kWh (P3 16:00-23:45)` |
-| `Time Of Highest Energy Price Tomorrow` | `Tomorrow Highest Price Time` |
-| `Time Of Lowest Energy Price Tomorrow` | `Tomorrow Lowest Price Time` |
-| `Time Of Highest Hourly Energy Price Tomorrow` | `Tomorrow Highest Hourly Price Time` |
-| `Time Of Lowest Hourly Energy Price Tomorrow` | `Tomorrow Lowest Hourly Price Time` |
-| `Next Day Price Update Status` | `Tomorrow Price Update Status` |
-| `Next Day Last Price Update Time` | `Tomorrow Data Loaded Time` |
-| `Next Day Price Update Status Message` | `Tomorrow Price Update Status Message` |
-| `Next Day Current Price Status` | `Tomorrow Current Price Status` |
-| `ENTSO-E Last Reboot` | `Last Reboot` |
-| `Entso-E Today NVS Status` | `Today NVS Status` |
-| `Entso-E Tomorrow NVS Status` | `Tomorrow NVS Status` |
-| `ENTSO-E Last Update Source` | `Last Update Source` |
-| `Today Data Date` | `Today Data Date` *(unchanged)* |
-| `Tomorrow Data Date` | `Tomorrow Data Date` *(unchanged)* |
+| entso-e-prices v4.3.1 name | v4.3.1 entity ID | EPrices v1.2 name | EPrices v1.2 entity ID |
+|---|---|---|---|
+| `ENTSO-E Hourly Prices EUR⁄kWh JSON` | `sensor.entso_e_prices_entso_e_hourly_prices_eur_kwh_json` | `Today JSON Hourly Prices EUR⁄kWh` | `sensor.eprices_today_json_hourly_prices_eur_kwh` |
+| `ENTSO-E 15-Min Prices EUR⁄kWh JSON (P1 00:00-07:45)` | `sensor.entso_e_prices_entso_e_15_min_prices_eur_kwh_json_p1_00_00_07_45` | `Today JSON 15-Min Prices EUR⁄kWh (P1 00:00-07:45)` | `sensor.eprices_today_json_15_min_prices_eur_kwh_p1_00_00_07_45` |
+| `ENTSO-E 15-Min Prices EUR⁄kWh JSON (P2 08:00-15:45)` | `sensor.entso_e_prices_entso_e_15_min_prices_eur_kwh_json_p2_08_00_15_45` | `Today JSON 15-Min Prices EUR⁄kWh (P2 08:00-15:45)` | `sensor.eprices_today_json_15_min_prices_eur_kwh_p2_08_00_15_45` |
+| `ENTSO-E 15-Min Prices EUR⁄kWh JSON (P3 16:00-23:45)` | `sensor.entso_e_prices_entso_e_15_min_prices_eur_kwh_json_p3_16_00_23_45` | `Today JSON 15-Min Prices EUR⁄kWh (P3 16:00-23:45)` | `sensor.eprices_today_json_15_min_prices_eur_kwh_p3_16_00_23_45` |
+| `Time Of Highest Energy Price Today` | `sensor.entso_e_prices_time_of_highest_energy_price_today` | `Today Highest Price Time` | `sensor.eprices_today_highest_price_time` |
+| `Time Of Lowest Energy Price Today` | `sensor.entso_e_prices_time_of_lowest_energy_price_today` | `Today Lowest Price Time` | `sensor.eprices_today_lowest_price_time` |
+| `Time Of Highest Hourly Energy Price Today` | `sensor.entso_e_prices_time_of_highest_hourly_energy_price_today` | `Today Highest Hourly Price Time` | `sensor.eprices_today_highest_hourly_price_time` |
+| `Time Of Lowest Hourly Energy Price Today` | `sensor.entso_e_prices_time_of_lowest_hourly_energy_price_today` | `Today Lowest Hourly Price Time` | `sensor.eprices_today_lowest_hourly_price_time` |
+| `Price Update Status` | `sensor.entso_e_prices_price_update_status` | `Today Price Update Status` | `sensor.eprices_today_price_update_status` |
+| `Last Price Update Time` | `sensor.entso_e_prices_last_price_update_time` | `Today Data Loaded Time` | `sensor.eprices_today_data_loaded_time` |
+| `Price Update Status Message` | `sensor.entso_e_prices_price_update_status_message` | `Today Price Update Status Message` | `sensor.eprices_today_price_update_status_message` |
+| `Current Price Status` | `sensor.entso_e_prices_current_price_status` | `Today Current Price Status` | `sensor.eprices_today_current_price_status` |
+| `ENTSO-E Next Day Hourly Prices EUR⁄kWh JSON` | `sensor.entso_e_prices_entso_e_next_day_hourly_prices_eur_kwh_json` | `Tomorrow JSON Hourly Prices EUR⁄kWh` | `sensor.eprices_tomorrow_json_hourly_prices_eur_kwh` |
+| `ENTSO-E Next Day 15-Min Prices EUR⁄kWh JSON (P1 00:00-07:45)` | `sensor.entso_e_prices_entso_e_next_day_15_min_prices_eur_kwh_json_p1_00_00_07_45` | `Tomorrow JSON 15-Min Prices EUR⁄kWh (P1 00:00-07:45)` | `sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p1_00_00_07_45` |
+| `ENTSO-E Next Day 15-Min Prices EUR⁄kWh JSON (P2 08:00-15:45)` | `sensor.entso_e_prices_entso_e_next_day_15_min_prices_eur_kwh_json_p2_08_00_15_45` | `Tomorrow JSON 15-Min Prices EUR⁄kWh (P2 08:00-15:45)` | `sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p2_08_00_15_45` |
+| `ENTSO-E Next Day 15-Min Prices EUR⁄kWh JSON (P3 16:00-23:45)` | `sensor.entso_e_prices_entso_e_next_day_15_min_prices_eur_kwh_json_p3_16_00_23_45` | `Tomorrow JSON 15-Min Prices EUR⁄kWh (P3 16:00-23:45)` | `sensor.eprices_tomorrow_json_15_min_prices_eur_kwh_p3_16_00_23_45` |
+| `Time Of Highest Energy Price Tomorrow` | `sensor.entso_e_prices_time_of_highest_energy_price_tomorrow` | `Tomorrow Highest Price Time` | `sensor.eprices_tomorrow_highest_price_time` |
+| `Time Of Lowest Energy Price Tomorrow` | `sensor.entso_e_prices_time_of_lowest_energy_price_tomorrow` | `Tomorrow Lowest Price Time` | `sensor.eprices_tomorrow_lowest_price_time` |
+| `Time Of Highest Hourly Energy Price Tomorrow` | `sensor.entso_e_prices_time_of_highest_hourly_energy_price_tomorrow` | `Tomorrow Highest Hourly Price Time` | `sensor.eprices_tomorrow_highest_hourly_price_time` |
+| `Time Of Lowest Hourly Energy Price Tomorrow` | `sensor.entso_e_prices_time_of_lowest_hourly_energy_price_tomorrow` | `Tomorrow Lowest Hourly Price Time` | `sensor.eprices_tomorrow_lowest_hourly_price_time` |
+| `Next Day Price Update Status` | `sensor.entso_e_prices_next_day_price_update_status` | `Tomorrow Price Update Status` | `sensor.eprices_tomorrow_price_update_status` |
+| `Next Day Last Price Update Time` | `sensor.entso_e_prices_next_day_last_price_update_time` | `Tomorrow Data Loaded Time` | `sensor.eprices_tomorrow_data_loaded_time` |
+| `Next Day Price Update Status Message` | `sensor.entso_e_prices_next_day_price_update_status_message` | `Tomorrow Price Update Status Message` | `sensor.eprices_tomorrow_price_update_status_message` |
+| `Next Day Current Price Status` | `sensor.entso_e_prices_next_day_current_price_status` | `Tomorrow Current Price Status` | `sensor.eprices_tomorrow_current_price_status` |
+| `ENTSO-E Last Reboot` | `sensor.entso_e_prices_entso_e_last_reboot` | `Last Reboot` | `sensor.eprices_last_reboot` |
+| `Entso-E Today NVS Status` | `sensor.entso_e_prices_entso_e_today_nvs_status` | `Today NVS Status` | `sensor.eprices_today_nvs_status` |
+| `Entso-E Tomorrow NVS Status` | `sensor.entso_e_prices_entso_e_tomorrow_nvs_status` | `Tomorrow NVS Status` | `sensor.eprices_tomorrow_nvs_status` |
+| `ENTSO-E Last Update Source` | `sensor.entso_e_prices_entso_e_last_update_source` | `Last Update Source` | `sensor.eprices_last_update_source` |
+| `Today Data Date` | `sensor.entso_e_prices_today_data_date` | `Today Data Date` *(unchanged)* | `sensor.eprices_today_data_date` |
+| `Tomorrow Data Date` | `sensor.entso_e_prices_tomorrow_data_date` | `Tomorrow Data Date` *(unchanged)* | `sensor.eprices_tomorrow_data_date` |
+
+---
 
 #### Buttons
 
-| entso-e-prices v4.3.1 name | EPrices v1.0 name |
-|---|---|
-| `Entso-E Force Update` | `Force Today's Update` |
-| `Entso-E Force Next Day Update` | `Force Tomorrow's Update` |
-| `Entso-E Reboot Device` | `Reboot Device` |
+| entso-e-prices v4.3.1 name | v4.3.1 entity ID | EPrices v1.2 name | EPrices v1.2 entity ID |
+|---|---|---|---|
+| `Entso-E Force Update` | `button.entso_e_prices_entso_e_force_update` | `Force Today's Update` | `button.eprices_force_today_s_update` |
+| `Entso-E Force Next Day Update` | `button.entso_e_prices_entso_e_force_next_day_update` | `Force Tomorrow's Update` | `button.eprices_force_tomorrow_s_update` |
+| `Entso-E Reboot Device` | `button.entso_e_prices_entso_e_reboot_device` | `Reboot Device` | `button.eprices_reboot_device` |
+
+---
 
 ### New sensors in EPrices v1.0 (no equivalent in v4.3.1)
 
-| Sensor | Purpose |
-|---|---|
-| `Today Last API Fetch Time` | Timestamp of last successful HTTP fetch for today |
-| `Tomorrow Last API Fetch Time` | Timestamp of last successful HTTP fetch for tomorrow |
-| `WiFi Signal` | RSSI in dBm |
-| `Uptime` | Human-readable uptime string |
+| EPrices v1.2 name | EPrices v1.2 entity ID | Purpose |
+|---|---|---|
+| `Today Last API Fetch Time` | `sensor.eprices_today_last_api_fetch_time` | Timestamp of last successful HTTP fetch for today |
+| `Tomorrow Last API Fetch Time` | `sensor.eprices_tomorrow_last_api_fetch_time` | Timestamp of last successful HTTP fetch for tomorrow |
+| `WiFi Signal` | `sensor.eprices_wifi_signal` | RSSI in dBm |
+| `Uptime` | `sensor.eprices_uptime` | Human-readable uptime string |
+
+---
 
 ### Sensor output changes
 
-| Sensor | v4.3.1 output | EPrices v1.0 output |
+| Sensor | v4.3.1 output | EPrices v1.2 output |
 |---|---|---|
 | `Last Reboot` | `Last reboot: 2026-04-04 20:10:10` | `2026-04-04 20:10:10` |
 | `Today NVS Status` | `Today NVS: Stored 96 pts for 2026-04-04` | `Stored 96 pts for 2026-04-04` |
@@ -186,23 +204,30 @@ The words "electricity" and "energy" were removed from all sensor names.
 | `Today Current Price Status` | `Valid` / `Missing` | `Valid` / `Missing` / `Stale` |
 | `Today Data Loaded Time` | Stamped on HTTP fetch only | Stamped on NVS load and HTTP fetch |
 | `Tomorrow Data Loaded Time` | `Never` after NVS boot load | Stamped on NVS load and HTTP fetch |
+| `Tomorrow Price Update Status Message` | *(various)* | `"No data yet"` on boot / after reboot (v1.2) |
+
+---
 
 ### HA entity ID changes
 
 All entity IDs changed due to the node name change from `entso-e-prices` to `eprices`.
 
-**Find and replace in all your automations and dashboards:**
+**Step 1 — bulk find and replace in all your automations and dashboards:**
 ```
 sensor.entso_e_prices_  →  sensor.eprices_
 button.entso_e_prices_  →  button.eprices_
 ```
 
-Then apply the individual sensor name slug changes from the tables above.
+**Step 2 — apply the individual sensor name slug renames** from the tables above
+for sensors whose names changed (not just the prefix).
+
+> **Tip:** After the bulk replace in Step 1, search for any remaining
+> `entso_e_prices_` strings to catch any that were missed.
 
 ### NVS data
 
 The NVS namespace changed from `entsoe2` to `eprices`. On first boot after
-flashing EPrices v1.0 the device will not find any stored data and will
+flashing EPrices the device will not find any stored data and will
 trigger a fresh HTTP fetch automatically. This is expected and safe.
 No manual NVS erase is required.
 
@@ -211,9 +236,10 @@ No manual NVS erase is required.
 ## Migration checklist
 
 - [ ] Flash `eprices.yaml` to the device
-- [ ] Update `secrets.yaml` — rename all `entsoe_` keys to `eprices_`; add `eprices_prov_fee` and `eprices_vat_rate`
-- [ ] In all HA automations: replace `entso_e_prices_` with `eprices_` in all entity IDs
-- [ ] Apply individual sensor name slug renames from the tables above
+- [ ] Update `secrets.yaml` — rename all `entsoe_` keys to `eprices_`; add `eprices_prov_fee`, `eprices_vat_rate`, and `eprices_neg_prov_fee`
+- [ ] In all HA automations: bulk replace `sensor.entso_e_prices_` → `sensor.eprices_` and `button.entso_e_prices_` → `button.eprices_`
+- [ ] Apply individual sensor slug renames from the tables above for sensors whose names changed
 - [ ] Remove any external HA automations that handled midnight bridge, boot recovery, or fetch scheduling — these are now all on-device
 - [ ] Verify the device fetches fresh data on first boot (check `Today NVS Status` and `Today Price Update Status Message`)
-- [ ] Update any HA dashboard cards referencing old entity IDs
+- [ ] Update any HA dashboard cards referencing old entity IDs
+- [ ] Verify the JSON sensor entity IDs in dashboards — the `⁄` character slug may differ from expected; check against actual HA entity registry if needed

README.md

@@ -16,19 +16,21 @@ Assistant automations are required for any core functionality.
 ## Features
 
 - Fetches **15-minute resolution** spot prices for **today** and **tomorrow**
-- Automatically applies your **provider fee** and **VAT rate** to raw €/MWh prices
+- Automatically applies your **provider fee** and **VAT rate** to raw €/MWh prices —
+  with **separate fee configuration for negative spot prices**
 - Exposes **96 per-day price points** plus **24-hour averages** as JSON text sensors
   for use in HA automations and dashboards
 - **NVS persistence** — prices survive device reboots without re-fetching
 - **Midnight bridge** — tomorrow's data automatically becomes today at 00:00, fully on-device
-- **Auto-retry logic** — up to 8 HTTP fetch attempts for both today and tomorrow
+- **Auto-retry logic** — up to 8 HTTP fetch attempts for both today and tomorrow,
+  with a **120-second stuck-fetch watchdog** that unblocks retries after TCP-level stalls
 - **DST-safe** — uses UNIX timestamps and binary search throughout, no hour-slot arithmetic
 - **Staleness detection** — `Today Current Price Status` shows `Stale` if stored date mismatches today
 - **Tomorrow live sensors** evaluate at `now + 86400s` — reflecting tomorrow at the same local time
 - Supports **any Energy-Charts bidding zone** (SI, DE-LU, AT, FR, HR, HU and more)
 - Full **diagnostic sensor suite** — NVS status, fetch attempts, API fetch times,
   data loaded times, WiFi signal, human-readable uptime
-- Provider fee and VAT rate configurable via `secrets.yaml` — **no code changes needed**
+- All fee and VAT settings configurable via `secrets.yaml` — **no code changes needed**
 
 ---
 
@@ -46,7 +48,7 @@ Assistant automations are required for any core functionality.
 | `eprices.yaml` | Main ESPHome configuration |
 | `eprices_nvs.h` | NVS helper — save/load price arrays to ESP32 flash |
 | `secrets.yaml` | Your local secrets (not committed to git) |
-| `CHANGELOG.md` | Complete sensor and entity ID reference for v1.0 |
+| `CHANGELOG.md` | Complete sensor and entity ID reference |
 | `VERSION.md` | Version history and release notes |
 | `ENTSO-E-PRICES-MIGRATION.md` | Optional — migration guide from the predecessor project |
 
@@ -71,6 +73,7 @@ eprices_timezone: "Europe/Ljubljana"
 eprices_country_bzn: "SI"
 eprices_prov_fee: "0.12"
 eprices_vat_rate: "0.22"
+eprices_neg_prov_fee: "0.30"
 ```
 
 **Key descriptions:**
@@ -79,8 +82,9 @@ eprices_vat_rate: "0.22"
 |---|---|
 | `eprices_timezone` | Your local timezone — must match a valid [IANA tz name](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones) |
 | `eprices_country_bzn` | Energy-Charts bidding zone code — see [supported zones](#supported-bidding-zones) |
-| `eprices_prov_fee` | Provider fee as a decimal multiplier, e.g. `"0.12"` = 12% |
-| `eprices_vat_rate` | VAT rate as a decimal multiplier, e.g. `"0.22"` = 22% |
+| `eprices_prov_fee` | Provider fee for **positive** spot prices — decimal multiplier, e.g. `"0.12"` = 12% |
+| `eprices_vat_rate` | VAT rate — decimal multiplier, e.g. `"0.22"` = 22% |
+| `eprices_neg_prov_fee` | Provider fee kept on **negative** spot prices — decimal multiplier, e.g. `"0.30"` means provider keeps 30%, pays you 70%; use `"0.00"` if provider passes the full negative price to you |
 | `eprices_api_encryption_key` | 32-byte base64 key for HA API encryption — generate with `openssl rand -base64 32` |
 
 ### 3) Flash to your ESP32
@@ -130,14 +134,37 @@ For the full list see the [Energy-Charts API documentation](https://api.energy-c
 | 13:55, 14:55 … 19:55 | Retry tomorrow fetch if previous attempt failed (max 8 total) |
 | Manual button press | Force immediate fetch for today or tomorrow |
 
+### Stuck-fetch watchdog
+
+If an HTTP request stalls at the TCP level (connection accepted but data
+delivery suspended), the 25 s application timeout may not fire. In that case
+the `is_updating_*` flag can stay `true` for several minutes, blocking all
+subsequent retries and manual button presses.
+
+The worker loop checks every 10 seconds: if `is_updating_today` or
+`is_updating_tomorrow` has been `true` for more than **120 seconds**, the flag
+is force-cleared and the status message is set to `"Fetch timeout – will retry"`.
+The next scheduled trigger or manual press then proceeds normally.
+
 ### Price calculation
 
 Raw prices from the API are in **€/MWh**. EPrices converts them to **€/kWh**
-and applies your provider fee and VAT:
+and applies your provider fee and VAT. Positive and negative spot prices use
+separate fee multipliers, configurable independently in `secrets.yaml`:
 
-```
-price_eur_kwh = (raw_eur_mwh / 1000) × (1 + prov_fee) × (1 + vat_rate)
-```
+| Market price | Formula |
+|---|---|
+| Positive (`raw ≥ 0`) | `(raw / 1000) × (1 + prov_fee) × (1 + vat_rate)` |
+| Negative (`raw < 0`) | `(raw / 1000) × (1 - neg_prov_fee) × (1 + vat_rate)` |
+
+The switch happens on the **raw API price** before any multiplier is applied.
+VAT is applied to both cases, consistent with net billing contracts where VAT
+is calculated on the monthly net sum (mathematically equivalent due to VAT
+being a linear multiplier).
+
+**Example with `prov_fee = 0.12`, `neg_prov_fee = 0.30`, `vat_rate = 0.22`:**
+- Spot price `+100 €/MWh` → `(100/1000) × 1.12 × 1.22` = **0.1366 €/kWh** (you pay)
+- Spot price `−50 €/MWh` → `(−50/1000) × 0.70 × 1.22` = **−0.0427 €/kWh** (you receive)
 
 ### Negative prices
 
@@ -245,7 +272,7 @@ safe on DST transition days (23-hour and 25-hour days).
 | Today Price Update Status | `sensor.eprices_today_price_update_status` | `SUCCESS` / `FAILED/WAITING` |
 | Tomorrow Price Update Status | `sensor.eprices_tomorrow_price_update_status` | `SUCCESS` / `FAILED/WAITING` |
 | Today Price Update Status Message | `sensor.eprices_today_price_update_status_message` | Detailed status string |
-| Tomorrow Price Update Status Message | `sensor.eprices_tomorrow_price_update_status_message` | Detailed status string |
+| Tomorrow Price Update Status Message | `sensor.eprices_tomorrow_price_update_status_message` | Detailed status string; `"Fetch timeout – will retry"` after watchdog trigger |
 
 ### Buttons
 

VERSION.md

@@ -1,5 +1,89 @@
 # EPrices – Version History
 
+## v1.2.1 — 2026-04-07
+
+Stability and housekeeping patch. No new sensors, no secrets changes,
+no entity ID changes. Drop-in replacement for v1.2.
+
+### ESP32 main task stack size increase
+
+Doubled the FreeRTOS main task stack from 8192 to 16384 bytes via
+`CONFIG_ESP_MAIN_TASK_STACK_SIZE`. Eliminates the stack overflow scenario
+most likely responsible for the spontaneous reboot observed in production
+on 2026-04-06 during a simultaneous NVS load + HTTP fetch/parse cycle.
+
+### Price vector heap pre-allocation at boot
+
+Added `.reserve(96)` on all four price vectors (`price_timestamps_today`,
+`price_values_today`, `price_timestamps_tomorrow`, `price_values_tomorrow`)
+in the `on_boot` lambda. Prevents repeated heap reallocation during NVS load
+and HTTP parse operations, reducing heap fragmentation and peak allocation
+pressure during the boot sequence.
+
+### Hourly JSON sensor cleared state unified
+
+`Today JSON Hourly Prices EUR⁄kWh` and `Tomorrow JSON Hourly Prices EUR⁄kWh`
+now publish `""` when cleared, matching the existing behaviour of all six
+15-minute JSON sensors. Previously they published `"[]"`.
+
+See `CHANGELOG.md` for full implementation details.
+
+---
+
+## v1.2 — 2026-04-06
+
+### HTTP fetch stuck-flag watchdog
+
+Fixed a production-observed reliability issue where a TCP-level stall during
+an HTTP fetch could lock `is_updating_today` or `is_updating_tomorrow` at
+`true` for several minutes, silently blocking all auto-retry triggers and
+manual button presses for the duration.
+
+A 120-second watchdog was added to both worker loops. If either `is_updating_*`
+flag has been held for more than 120 seconds, the worker force-clears it and
+sets the status message to `"Fetch timeout – will retry"`, allowing the next
+scheduled retry or manual press to proceed immediately.
+
+New globals: `is_updating_today_since`, `is_updating_tomorrow_since`.
+
+### Tomorrow auto-retry attempt counter fix
+
+`tomorrow_retry_count` was not being incremented in the 13:55 and 14:55–19:55
+hourly retry triggers, causing the `Tomorrow API Fetch Attempts` diagnostic
+sensor to undercount after the first scheduled attempt at 13:25.
+
+### Status message improvements
+
+- `tomorrow_update_status_message` initial value changed from
+  `"Waiting for 13:20"` to `"No data yet"`
+- `clear_tomorrow_prices` end message changed from
+  `"Cleared – awaiting next 13:20 window"` to
+  `"Cleared – awaiting fetch window"`
+
+See `CHANGELOG.md` for full implementation details.
+
+---
+
+## v1.1 — 2026-04-06
+
+### Negative price provider fee
+
+Added separate provider fee support for negative spot prices via a new
+`eprices_neg_prov_fee` secret key. Positive and negative market prices
+now use independent fee multipliers, correctly modelling contracts where
+the provider's fee structure differs between the two cases.
+
+Price calculation:
+- Positive: `(raw / 1000) × (1 + prov_fee) × (1 + vat_rate)`
+- Negative: `(raw / 1000) × (1 - neg_prov_fee) × (1 + vat_rate)`
+
+VAT is applied to both, consistent with net billing where VAT is calculated
+on the monthly net sum (linear equivalence applies).
+
+See `CHANGELOG.md` for full implementation details.
+
+---
+
 ## v1.0 — 2026-04-05
 
 First public release.
@@ -49,4 +133,4 @@ persistently in ESP32 NVS flash so they survive reboots without re-fetching.
 | `secrets.yaml` | Local secrets — not committed to git |
 | `CHANGELOG.md` | Full sensor and entity ID reference for v1.0 |
 | `README.md` | Installation guide and full sensor reference |
-| `ENTSO-E-PRICES-MIGRATION.md` | Optional — migration guide from the predecessor project |
+| `ENTSO-E-PRICES-MIGRATION.md` | Optional — migration guide from the predecessor project |

eprices.yaml

@@ -1,13 +1,48 @@
 # =============================================================================
-# ESPHome: EPrices v1.0
-#
-# ESP32 firmware that fetches day-ahead electricity spot prices from the
-# public Energy-Charts API (https://api.energy-charts.info) and exposes
-# them as Home Assistant sensors. No API token required.
+# ESPHome: EPrices v1.2.1
 #
 # Electricity price data provided by Energy-Charts (https://energy-charts.info)
 # under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/).
 #
+# v1.2.1 changes (2026-04-07):
+# - CONFIG_ESP_MAIN_TASK_STACK_SIZE raised from 8192 to 16384 bytes via
+#   esp32: framework: sdkconfig_options — eliminates stack overflow scenario
+#   observed in production during simultaneous NVS load + HTTP fetch/parse
+# - Price vectors pre-allocated at boot with .reserve(96) in on_boot lambda:
+#   price_timestamps_today, price_values_today,
+#   price_timestamps_tomorrow, price_values_tomorrow
+#   prevents repeated heap reallocation during NVS load and HTTP parse cycles
+# - Hourly JSON sensors now publish "" when cleared (was "[]") —
+#   consistent with all six 15-min JSON sensors
+#
+# v1.2 changes (2026-04-06):
+# - HTTP fetch stuck-flag watchdog (120 s) added to today and tomorrow workers:
+#   if is_updating_today / is_updating_tomorrow stays true for >120 s (TCP
+#   stall not caught by app-level timeout), the flag is force-cleared and
+#   status message set to "Fetch timeout – will retry"
+# - New globals: is_updating_today_since, is_updating_tomorrow_since
+#   set alongside is_updating_* = true in smart_price_update and
+#   smart_tomorrow_price_update
+# - tomorrow_retry_count++ added before .execute() in 13:55 and 14:55–19:55
+#   hourly retry triggers (counter was not incrementing after attempt #1)
+# - tomorrow_update_status_message initial_value: "Waiting for 13:20"
+#   → "No data yet" (removes misleading time reference after afternoon reboot)
+# - clear_tomorrow_prices end message: "Cleared – awaiting next 13:20 window"
+#   → "Cleared – awaiting fetch window"
+#
+# v1.1 changes (2026-04-06):
+# - Separate provider fee for negative spot prices (eprices_neg_prov_fee):
+#   positive prices: (raw / 1000) × (1 + prov_fee)     × (1 + vat_rate)
+#   negative prices: (raw / 1000) × (1 - neg_prov_fee) × (1 + vat_rate)
+#   switch happens on raw API price before any multiplier is applied
+#   VAT applied to both cases (consistent with net billing + end-of-month VAT)
+#   0.30 = provider keeps 30%, pays you 70% of negative price
+#   0.00 = provider passes full negative price to you (no fee)
+# - New substitution: neg_prov_fee_value (!secret eprices_neg_prov_fee)
+# - New global: neg_prov_fee (double)
+# - MULT split into MULT_POS / MULT_NEG in parse_energy_charts_today_script
+#   and parse_energy_charts_tomorrow_script
+#
 # v1.0 release notes:
 # - Fetches 15-min and hourly spot prices for today and tomorrow
 # - Prices converted from raw €/MWh to €/kWh with provider fee and VAT applied
@@ -33,6 +68,7 @@
 #   eprices_country_bzn           e.g. "SI"
 #   eprices_prov_fee              e.g. "0.12"  (provider fee, decimal multiplier)
 #   eprices_vat_rate              e.g. "0.22"  (VAT rate, decimal multiplier)
+#   eprices_neg_prov_fee          e.g. "0.30"  (neg price provider fee, decimal multiplier)
 #
 # See README.md for full installation instructions and sensor reference.
 # See CHANGELOG.md for complete sensor and entity ID listing.
@@ -40,9 +76,10 @@
 # =============================================================================
 
 substitutions:
-  country_bzn_value: !secret eprices_country_bzn
-  prov_fee_value:    !secret eprices_prov_fee
-  vat_rate_value:    !secret eprices_vat_rate
+  country_bzn_value:    !secret eprices_country_bzn
+  prov_fee_value:       !secret eprices_prov_fee
+  vat_rate_value:       !secret eprices_vat_rate
+  neg_prov_fee_value:   !secret eprices_neg_prov_fee
 
 esphome:
   name: eprices
@@ -60,11 +97,19 @@ esphome:
           } else {
             id(boot_time) = 0;
           }
+          // Pre-allocate price vectors to avoid repeated heap reallocation
+          // during NVS load and HTTP fetch/parse cycles
+          id(price_timestamps_today).reserve(96);
+          id(price_values_today).reserve(96);
+          id(price_timestamps_tomorrow).reserve(96);
+          id(price_values_tomorrow).reserve(96);
 
 esp32:
   board: esp32dev
   framework:
     type: esp-idf
+    sdkconfig_options:
+      CONFIG_ESP_MAIN_TASK_STACK_SIZE: "16384"
     # No include_builtin_idf_components needed — nvs headers are always
     # available in esp-idf framework; eprices_nvs.h includes them directly.
 
@@ -175,6 +220,15 @@ time:
       - seconds: /10
         then:
           - lambda: |-
+              if (id(is_updating_today) && id(is_updating_today_since) > 0) {
+                time_t now_ts = (time_t)id(ha_time).now().timestamp;
+                if (now_ts - id(is_updating_today_since) > 120) {
+                  ESP_LOGW("eprices", "Worker: is_updating_today stuck >120s, force-clearing");
+                  id(is_updating_today) = false;
+                  id(is_updating_today_since) = 0;
+                  id(update_status_message) = "Fetch timeout – will retry";
+                }
+              }
               if (id(need_today_update) && !id(is_updating_today)) {
                 ESP_LOGI("eprices", "Worker: starting Today update");
                 id(need_today_update) = false;
@@ -184,6 +238,15 @@ time:
       - seconds: /10
         then:
           - lambda: |-
+              if (id(is_updating_tomorrow) && id(is_updating_tomorrow_since) > 0) {
+                time_t now_ts = (time_t)id(ha_time).now().timestamp;
+                if (now_ts - id(is_updating_tomorrow_since) > 120) {
+                  ESP_LOGW("eprices", "Worker: is_updating_tomorrow stuck >120s, force-clearing");
+                  id(is_updating_tomorrow) = false;
+                  id(is_updating_tomorrow_since) = 0;
+                  id(tomorrow_update_status_message) = "Fetch timeout – will retry";
+                }
+              }
               auto t = id(ha_time).now();
               bool in_window = (t.hour > 13 && t.hour < 23) ||
                                (t.hour == 13 && t.minute >= 20) ||
@@ -312,7 +375,8 @@ time:
                 return;
               }
 
-              ESP_LOGW("eprices", "Auto tomorrow: attempt #%d at 13:55", id(tomorrow_retry_count) + 1);
+              id(tomorrow_retry_count)++;
+              ESP_LOGW("eprices", "Auto tomorrow: attempt #%d at 13:55", id(tomorrow_retry_count));
               id(smart_tomorrow_price_update).execute();
 
       # Attempts #3.. at 14:55, 15:55, 16:55, 17:55, 18:55, 19:55 (capped to 8)
@@ -333,7 +397,8 @@ time:
                 return;
               }
 
-              ESP_LOGW("eprices", "Auto tomorrow: attempt #%d at %02d:55", id(tomorrow_retry_count) + 1, t.hour);
+              id(tomorrow_retry_count)++;
+              ESP_LOGW("eprices", "Auto tomorrow: attempt #%d at %02d:55", id(tomorrow_retry_count), t.hour);
               id(smart_tomorrow_price_update).execute();
 
       - minutes: /1
@@ -452,6 +517,9 @@ globals:
   - id: is_updating_today
     type: bool
     initial_value: 'false'
+  - id: is_updating_today_since
+    type: time_t
+    initial_value: '0'
 
   - id: tomorrow_last_successful_update
     type: time_t
@@ -468,7 +536,7 @@ globals:
     initial_value: 'false'
   - id: tomorrow_update_status_message
     type: std::string
-    initial_value: '"Waiting for 13:20"'
+    initial_value: '"No data yet"'
   - id: tomorrow_retry_count
     type: int
     initial_value: '0'
@@ -484,6 +552,9 @@ globals:
   - id: is_updating_tomorrow
     type: bool
     initial_value: 'false'
+  - id: is_updating_tomorrow_since
+    type: time_t
+    initial_value: '0'
 
   # --- Country code for Energy-Charts API (wired from secret) ---
   - id: country_bzn
@@ -497,6 +568,9 @@ globals:
   - id: vat_rate
     type: double
     initial_value: '${vat_rate_value}'
+  - id: neg_prov_fee
+    type: double
+    initial_value: '${neg_prov_fee_value}'
 
   # --- Pre-computed fetch URLs (url: !lambda not supported in scripts) ---
   - id: fetch_url_today
@@ -1261,7 +1335,8 @@ script:
       raw_body: string
     then:
       - lambda: |-
-          const double MULT = (1.0 + id(prov_fee)) * (1.0 + id(vat_rate));
+          const double MULT_POS = (1.0 + id(prov_fee))     * (1.0 + id(vat_rate));
+          const double MULT_NEG = (1.0 - id(neg_prov_fee)) * (1.0 + id(vat_rate));
 
           id(price_values_today).clear();
           id(price_timestamps_today).clear();
@@ -1350,7 +1425,7 @@ script:
             if (end1 == ts_toks[i].c_str() || end2 == prc_toks[i].c_str()) continue;
             if (unix_ts <= 0) continue;
 
-            float eur_kwh = (float)((double)raw_mwh * MULT / 1000.0);
+            float eur_kwh = (float)((double)raw_mwh * (raw_mwh >= 0 ? MULT_POS : MULT_NEG) / 1000.0);
             id(price_timestamps_today).push_back(unix_ts);
             id(price_values_today).push_back(eur_kwh);
           }
@@ -1369,7 +1444,8 @@ script:
       raw_body: string
     then:
       - lambda: |-
-          const double MULT = (1.0 + id(prov_fee)) * (1.0 + id(vat_rate));
+          const double MULT_POS = (1.0 + id(prov_fee))     * (1.0 + id(vat_rate));
+          const double MULT_NEG = (1.0 - id(neg_prov_fee)) * (1.0 + id(vat_rate));
 
           id(price_values_tomorrow).clear();
           id(price_timestamps_tomorrow).clear();
@@ -1437,7 +1513,7 @@ script:
             if (end1 == ts_toks[i].c_str() || end2 == prc_toks[i].c_str()) continue;
             if (unix_ts <= 0) continue;
 
-            float eur_kwh = (float)((double)raw_mwh * MULT / 1000.0);
+            float eur_kwh = (float)((double)raw_mwh * (raw_mwh >= 0 ? MULT_POS : MULT_NEG) / 1000.0);
             id(price_timestamps_tomorrow).push_back(unix_ts);
             id(price_values_tomorrow).push_back(eur_kwh);
           }
@@ -1754,6 +1830,7 @@ script:
             return;
           }
           id(is_updating_today) = true;
+          id(is_updating_today_since) = (time_t)id(ha_time).now().timestamp;
           id(last_update_attempt) = id(ha_time).now().timestamp;
           id(retry_count)++;
           { char buf[8]; snprintf(buf, sizeof(buf), "%d", id(retry_count)); id(today_price_update_attempts).publish_state(buf); }
@@ -1857,6 +1934,7 @@ script:
             return;
           }
           id(is_updating_tomorrow) = true;
+          id(is_updating_tomorrow_since) = (time_t)id(ha_time).now().timestamp;
           id(tomorrow_last_update_attempt) = id(ha_time).now().timestamp;
           id(tomorrow_retry_count)++;
           { char buf[8]; snprintf(buf, sizeof(buf), "%d", id(tomorrow_retry_count)); id(tomorrow_price_update_attempts).publish_state(buf); }
@@ -2044,7 +2122,7 @@ script:
           id(today_current_max_hourly_price_percentage).publish_state(NAN);
           id(last_update_success) = false;
           id(update_status_message) = "Cleared – awaiting NVS or HTTP";
-          id(json_hourly_prices_kwh).publish_state("[]");
+          id(json_hourly_prices_kwh).publish_state("");
           id(json_15min_prices_kwh_p1_00_00_07_45).publish_state("");
           id(json_15min_prices_kwh_p2_08_00_15_45).publish_state("");
           id(json_15min_prices_kwh_p3_16_00_23_45).publish_state("");
@@ -2077,7 +2155,7 @@ script:
           id(tomorrow_min_hourly_price).publish_state(NAN);
           id(tomorrow_max_hourly_price).publish_state(NAN);
           id(tomorrow_current_max_hourly_price_percentage).publish_state(NAN);
-          id(json_tomorrow_hourly_prices_kwh).publish_state("[]");
+          id(json_tomorrow_hourly_prices_kwh).publish_state("");
           id(json_tomorrow_15min_prices_kwh_p1_00_00_07_45).publish_state("");
           id(json_tomorrow_15min_prices_kwh_p2_08_00_15_45).publish_state("");
           id(json_tomorrow_15min_prices_kwh_p3_16_00_23_45).publish_state("");
@@ -2086,7 +2164,7 @@ script:
           id(tomorrow_min_hourly_price_time_str) = "--:--";
           id(tomorrow_max_hourly_price_time_str) = "--:--";
           id(tomorrow_last_update_success) = false;
-          id(tomorrow_update_status_message) = "Cleared – awaiting next 13:20 window";
+          id(tomorrow_update_status_message) = "Cleared – awaiting fetch window";
           id(tomorrow_current_price_status_str) = "Cleared";
           id(tomorrow_price_update_status).update();
           id(tomorrow_price_status_message).update();
@@ -2094,4 +2172,4 @@ script:
           id(tomorrow_nvs_status).publish_state("Cleared");
           id(tomorrow_last_api_fetch_time) = std::string("Never");
           id(tomorrow_last_api_fetch_time_sensor).publish_state("Never");
-          id(tomorrow_last_price_update_time).publish_state("Outside fetch window");
+          id(tomorrow_last_price_update_time).publish_state("Outside fetch window");

secrets.yaml

@@ -0,0 +1,107 @@
+# =============================================================================
+# EPrices – Template secrets file
+# Copy this file to your ESPHome config directory as "secrets.yaml"
+# and fill in your own values.
+#
+# Notes on value formats:
+#  - All values are strings in secrets.yaml.
+#  - Numeric values (prov_fee, vat_rate) must use a DECIMAL DOT (e.g. 0.12),
+#    not a decimal comma. They are loaded as substitutions and passed directly
+#    into C++ double globals, so the dot is mandatory.
+# =============================================================================
+
+# --- WiFi credentials (shared with other ESPHome devices - remove if already present) ---
+wifi_ssid: "your_wifi_ssid"
+wifi_password: "your_wifi_password"
+
+# --- EPrices fallback AP (shown when WiFi is unavailable) ---
+eprices_fallback_ap_ssid: "EPrices-Fallback"
+eprices_fallback_ap_password: "your_fallback_ap_password"
+
+# --- ESPHome API encryption key (generate with: esphome generate-api-key) ---
+eprices_api_encryption_key: "your_base64_api_encryption_key_here"
+
+# --- Timezone string (IANA format, must match your location) ---
+# Examples: "Europe/Ljubljana", "Europe/Berlin", "Europe/London"
+eprices_timezone: "Europe/Ljubljana"
+
+# --- Bidding zone for Energy-Charts API ---
+# This determines which country's spot prices are fetched.
+# Examples: "SI" (Slovenia), "DE-LU" (Germany/Luxembourg), "AT" (Austria),
+#           "FR" (France), "IT-North" (Italy North), "HR" (Croatia)
+# Full list: https://api.energy-charts.info/
+eprices_country_bzn: "SI"
+
+# --- Provider fee multiplier for POSITIVE spot prices ---
+# Added on top of the raw spot price to account for your energy provider's fee.
+# Value is a DECIMAL MULTIPLIER, not a percentage.
+# Example: 0.12 means 12% provider fee added to the spot price.
+# Use decimal DOT, not comma (correct: 0.12 | wrong: 0,12).
+eprices_prov_fee: "0.12"
+
+# --- Provider fee multiplier for NEGATIVE spot prices ---
+# When the market spot price is negative, the provider pays you a share of
+# the negative price. This value is the fraction the provider keeps.
+# Example: 0.30 means provider keeps 30%, pays you 70% of the negative price.
+# Example: 0.00 means provider passes the full negative price to you (no fee).
+# Use decimal DOT, not comma (correct: 0.30 | wrong: 0,30).
+eprices_neg_prov_fee: "0.30"
+
+# --- VAT rate multiplier ---
+# Value added to the price to account for Value Added Tax in your country.
+# Value is a DECIMAL MULTIPLIER, not a percentage.
+# Example: 0.22 means 22% VAT (Slovenia). Germany is 0.19, Austria is 0.20.
+# Use decimal DOT, not comma (correct: 0.22 | wrong: 0,22).
+eprices_vat_rate: "0.22"
+
+# ==============================================================================
+# --- ADDITIONAL INFO: Bidding zone list for Energy-Charts API on 2026-04-04 ---
+# (Check https://api.energy-charts.info/ for potential future changes)
+#
+# AT - Austria (click to show all available bidding zones)
+# BE - Belgium
+# BG - Bulgaria
+# CH - Switzerland
+# CZ - Czech Republic
+# DE-LU - Germany, Luxembourg
+# DE-AT-LU - Germany, Austria, Luxembourg
+# DK1 - Denmark 1
+# DK2 - Denmark 2
+# EE - Estionia
+# ES - Spain
+# FI - Finland
+# FR - France
+# GR - Greece
+# HR - Croatia
+# HU - Hungary
+# IT-Calabria - Italy Calabria
+# IT-Centre-North - Italy Centre North
+# IT-Centre-South - Italy Centre South
+# IT-North - Italy North
+# IT-SACOAC - Italy Sardinia Corsica AC
+# IT-SACODC - Italy Sardinia Corsica DC
+# IT-Sardinia - Italy Sardinia
+# IT-Sicily - Italy Sicily
+# IT-South - Italy South
+# LT - Lithuania
+# LV - Latvia
+# ME - Montenegro
+# NL - Netherlands
+# NO1 - Norway 1
+# NO2 - Norway 2
+# NO2NSL - Norway North Sea Link
+# NO3 - Norway 3
+# NO4 - Norway 4
+# NO5 - Norway 5
+# PL - Poland
+# PT - Portugal
+# RO - Romania
+# RS - Serbia
+# SE1 - Sweden 1
+# SE2 - Sweden 2
+# SE3 - Sweden 3
+# SE4 - Sweden 4
+# SI - Slovenia
+# SK - Slovakia
+# ==============================================================================
+