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ADR-0032: A Temperature popup — the history of the two home-screen temperatures, and the forecast for the second one, pushed by HA from its statistics while the popup is open

Status: Accepted (2026-10-06, asked for and decided by the author; not yet tried on a tablet) Date: 2026-10-06

Context

The home screen shows two temperatures: the room's and a second sensor (a greenhouse at the author's home; outdoors for most other homes). The author asked for a history in a popup on a long press of the room's, and, for the second one, a history and the forecast, both as graphs, « without taking too many resources ». He then decided (2026-10-06):

  1. the forecast is shown on the second temperature's popup; it extends the curve when that temperature is outdoors, and stays apart under the name « Dehors, prévu » (outdoors, forecast) otherwise — a blueprint checkbox says which;
  2. three views: 24 hours, 7 days, 30 days.

Constraints that hold: push-only and events-only (ADR-0001, ADR-0025), the firmware names no entity (ADR-0019); the shared modal chrome (ADR-0009) and the single registry (ADR-0013); no hardcoded colour (ADR-0029); public HA files without a real entity (ADR-0024). The build has LV_USE_CHART 0 and LV_USE_CANVAS 0; LV_USE_LINE 1.

Decision

  • Same model as the Energy popup (ADR-0028). The tablet stores nothing in NVS. A long press on a temperature runs tab5_historique_ouvrir (cle = salon or serre); opening and each view button emit esphome.tab5_historique (cle, vue = jour, semaine or mois). The blueprint « Tab5 — emplacements », which knows the sensor of each slot, starts script.tab5_historique (package tab5_historique.yaml) with that sensor and the new checkbox serre_exterieure. The script pushes once tab5_maj_historique (cle, vue, entete, mesures, previsions); nothing is pushed while the popup is closed.
  • Data: HA's long-term statistics. recorder.get_statistics, types mean / min / max: period hour for 24 h (24 full hours + the current one) and 7 days (3-hour slots aligned on 0 h, 3 h…: 56 + the current one; mean of the hourly means, min of the mins, max of the maxes), period day for 30 days (30 days + today). Hourly statistics are kept forever by HA, so the three views work as soon as the sensor has a state_class; no helper, no extra database write.
  • Forecast, second temperature only: weather.get_forecasts on the weather entity of sensor.tab5_meteo (the one the tablet already uses): hourly for 24 h (24 points) and 7 days (every 3 h over 72 h) when the entity provides it, daily (or twice daily) otherwise and for 30 days (tomorrow, 3 days or 7 days); a daily point sits at local noon and carries its min and max. 48 points at most.
  • Wall-clock minutes. Slots and points are placed in minutes from the first slot, counted on the local clock (timestamp difference plus the difference of UTC offsets): across a DST change a slot may hold one hour more or less, the axis and the labels never shift. The header gives the first slot as a naive local AAAA-MM-JJTHH:MM; the firmware computes its labels from it with civil-date arithmetic, no time zone.
  • Drawing without a chart widget (tab5_historique.cpp): a lv_line for the means (ending on the current value, with a dot), plain lv_obj bars from min to max behind it, a second lv_line in gold for the forecast on a tinted background after a « Maintenant » line, gold min-max bars for daily forecast points, 1-2-5 degree grid (at most 5 intervals), a time axis at 3 h / 6 h / 12 h / 1 day… (10 labels at most), a legend. LVGL 9.5 dashes only horizontal and vertical lines, so the forecast is told apart by its colour and background. lv_line_set_points() does not copy its points: they live in the PSRAM block with the series.
  • Memory. One block in PSRAM (internal RAM as a fallback), allocated on the first opening, ~6 KB: the three views of the temperature shown and the two point arrays. Opening the other temperature forgets them. Widgets are created once.
  • Gestures. A long press on the room's temperature (the invisible zone btn_reglables_liste, whose tap unfolds the list of the − / + tile, ADR-0033; since 2026-10-09 its tap opens the climate carousel, ADR-0038) or on the second one (btn_serre_games, whose tap still opens the Arcade: LVGL sends no short click after a long press). A slot without a sensor (zone absent) does nothing.
  • Shared view buttons. energie_vue_btn.yaml becomes vue_btn.yaml with a prefixe var, used by both popups.

Compatibility

  • New blueprint, older firmware: the event never comes; the new input has a default (false).
  • New firmware, older blueprint or no package: the popup opens and says « En attente de Home Assistant ».
  • Sensor without statistics (no state_class): empty mesures, the popup says « Aucun historique »; the « Now » card still shows the current value.
  • No weather entity: no forecast, the fourth card shows « -- ».

Consequences

  • One more package (twenty-three), C++ unit, service (twenty-two) and two UI files (historique_popup.yaml, the historique_carte.yaml template included four times), one more HA package and one blueprint input.
  • tests/test_historique.py renders the package's real templates on simulated get_statistics and get_forecasts answers (both DST changes, a missing hour, a failed call) against an independent Python computation, checks the blueprint branch, the demo and the firmware's limits; the templates were also rendered by the author's Home Assistant on its real statistics and Météo-France forecast (2026-10-06).
  • The demo answers the event; the off-device render pushes the answer itself (five new screens).