Standalone-electricity-price-ticker/CHANGELOG.md

Changelog

All notable changes to this project will be documented in this file.

This project follows a simple semantic versioning style:
MAJOR.MINOR.PATCH

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[6.0.0] - 2026-01-27

Added

• Daily fetch + NVS storage (ESP32‑C3 NVS)

  • Introduced non‑volatile storage for daily price data using the existing Preferences (NVS) subsystem under the "my-ticker" namespace.
  • Stored fields:
    • data_day, data_mon, data_year (calendar date of the data)
    • data_prc (raw JSON returned from the Energy‑Charts API)
    • data_last_store (UNIX timestamp of last successful store)
  • On boot, after Wi‑Fi and NTP time sync:
    • The ticker checks NVS for stored data.
    • If the stored date matches today, the JSON is deserialized and used directly (no initial API call needed).
    • If the stored date is not today (or invalid), the data is ignored and the ticker behaves as if no data is available yet.

• Midnight rollover + daily fetch logic

  • The system now performs one daily fetch per day, instead of hourly:
    • On boot: fetch only if NVS does not already contain valid data for today.
    • After local midnight: invalidate the previous day’s data and trigger a new fetch for the new day.
  • As soon as a local‑time day change is detected:
    • isTodayDataAvailable is set to false.
    • The display state is forced to "No data for today" (NO_DATA_OFFSET).
    • The white LED is turned off (same behavior as “no data”).
    • A midnight fetch phase is activated.

• Midnight fetch retry strategy

  • When midnight is detected:
    • First fetch is scheduled immediately.
    • If it fails (HTTP error or JSON/“day mismatch”), the system stays in "No data for today" and the LEDs remain off.
  • Retry policy during midnight phase:
    1. Retry every 10 minutes, up to 5 attempts.
    2. If still unsuccessful, retry only once at the top of each following hour until fresh data for the new day is retrieved.
  • As soon as a successful fetch for today is obtained:
    • isTodayDataAvailable = true.
    • The enforced NO_DATA_OFFSET state is cleared back to CURRENT_PRICES.
    • The white LED resumes indicating the current 15‑minute segment price.
    • The entire successful JSON payload and metadata are saved back into NVS.

• Improved resilience after power loss

  • If the device reboots during the same day:
    • It can restore and reuse the last successfully stored daily data from NVS.
    • This avoids unnecessary API calls and gives a fast “warm start” after power outages.
  • If the device reboots on the next day:
    • Yesterday’s stored data is not used for display (to avoid confusion).
    • The display starts in "No data for today" until the first successful fetch.

• Extended secondary (info) menu

  • The secondary info screen (reachable via double‑click on the button) is extended from 16 to 20 lines, still shown as 4‑line pages.
  • Existing info retained:
    • Current time and date.
    • Last successful update timestamp.
    • Daily average price.
    • Wi‑Fi RSSI and device IP.
    • API success ratio.
    • Uptime.
    • Credits and version information.
  • New NVS status section (first defined around lines 12–15, later rearranged in your version):
    • Shows:
      • NVS data status (NVS status:)
      • Stored data date (Data day: DD.MM.YYYY or Data day: none)
      • Last store timestamp (Last save: DD.MM.YY or Last save: none)
      • Basic quick status:
        • NVS: OK (today) – valid data for today loaded from NVS
        • NVS: old data – NVS has data, but not from today (ignored for display)
        • NVS: empty – no stored price data present

Changed

• API call strategy

  • Removed regular top‑of‑hour automatic fetching.
  • API calls now occur only:
    • Once at boot (if NVS has no valid data for today).
    • After midnight (with the retry strategy described above).
    • On user‑initiated long‑press (manual refresh).
  • This significantly reduces network load while keeping behavior safe and predictable.

• UI & behavior around day boundaries

  • At midnight / day change:
    • Display is immediately set to:
      • Line 0: No data for today
      • Line 1: Press & hold to
      • Line 2: refresh manually
    • White LED is turned off (no price indication until new data arrives).
  • Once data for the new day is available:
    • The ticker returns to the usual 15‑minute detail + hourly display mode.

• Versioning and info screens

  • Version bumped to v6.0 and reflected in:
    • Source file header comment.
    • Secondary menu text (price ticker v6.0).
    • New version documentation (VERSION.md / CHANGELOG.md / README.md).

• Long‑press threshold (in repository version)

  • Long‑press detection threshold extended from 2s to 3s (in your repository copy) to avoid accidental manual refreshes.

Fixed / Ensured

• Yesterday’s data is never shown as if it were today’s:
  • On boot: previous‑day NVS data is ignored for display.
  • After midnight: in‑RAM data is invalidated and the UI explicitly shows "No data for today" until fresh data is fetched.
• LED state is always consistent with the availability of today’s data:
  • LED off → no today data (or negative price).
  • LED patterns → valid today data and a positive price in the current 15‑minute interval.

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[5.5.0] - 2025-10-27

First 15‑minute detail version and DST‑fixed base, which v6.0 builds upon.

Added

• 15‑minute detail mode:
  • Primary display shows:
    • Current hour average.
    • Four 15‑minute prices in compact format (XX XX XX XX).
    • Next 2 hours’ averages.
  • LED behavior switched from hourly‑based to 15‑minute‑segment based.
• Compact price format:
  • 15‑minute values shown as 2‑digit hundredths (e.g. +99 -07 24 11).
• DST / timezone handling:
  • configTzTime() with TZ_CET_CEST for automatic CET ↔ CEST switching.
• Aggressive retry and state enforcement:
  • Improved logic for:
    • Handling stale data.
    • Enforcing "No data for today" state when needed.
    • Aggressively retrying fetches after HTTP/JSON failures.
• UI and usability tweaks:
  • Button:
    • Single click: scroll primary list (hourly view).
    • Double click: switch primary/secondary list.
    • Long press: manual refresh.
  • Secondary info list:
    • Date/time, last update, daily average, Wi‑Fi and API stats, uptime, credits.

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Older versions

Earlier versions (≤5.4) introduced the basic ticker behavior, LCD layout, Energy‑Charts API integration, and the initial presence sensor / backlight / LED logic.

Those versions are not fully documented here, but key user‑visible behavior is maintained in v6.0 unless explicitly noted in this changelog.