#!/usr/bin/env bash
# Odstraní predikované PV intervaly (a navázaný tracking přesnosti) pro jeden kalendářní den v Europe/Prague.
#
# VAROVÁNÍ (provozní / datová kontinuita)
# ────────────────────────────────────────
# - Řád v repozitáři je držet historické běhy FVE forecastu pro analýzu a učení delty (@see docs/04-modules/forecast.md).
# - Používej jen když vědomě potřebuješ „načisto“ vygenerovat nový forecast (forecast service).
# - Fyzický breaker řeší měnič/Deye — skript jen čistí databázi od uloženého PV forecastu.
#
# Nenahrazuje mazání/load baseline spotřeby (`consumption_baseline_stats` / její výpočet).
#
# Použití:
#   export DATABASE_URL='postgres://…/ems'
#   ./scripts/wipe_pv_forecast_prague_day.sh                    # dnešní den (Europe/Prague), všechny lokality
#   ./scripts/wipe_pv_forecast_prague_day.sh 2026-05-02        # konkrétní datum YYYY-MM-DD
#   ./scripts/wipe_pv_forecast_prague_day.sh 2026-05-02 2     # jen site.id = 2 (např. home-01)
#
# Šedý režim (jen počty, žádné mazání):
#   DRY_RUN=1 ./scripts/wipe_pv_forecast_prague_day.sh 2026-05-02 2

set -euo pipefail

DAY="${1:-$(TZ=Europe/Prague date +%Y-%m-%d)}"
SITE_ID="${2:-}"

if ! [[ "$DAY" =~ ^[0-9]{4}-[0-9]{2}-[0-9]{2}$ ]]; then
  echo "Datum musí být YYYY-MM-DD, dostal jsem: $DAY" >&2
  exit 1
fi

if [[ -z "${DATABASE_URL:-}" ]] && [[ -z "${PGHOST:-}" ]]; then
  echo "Nastav DATABASE_URL nebo standardní PG proměnné (PGHOST, PGUSER, PGDATABASE, …)." >&2
  exit 1
fi

PSQL=(psql -v ON_ERROR_STOP=1)
if [[ -n "${DATABASE_URL:-}" ]]; then
  PSQL+=("$DATABASE_URL")
else
  PSQL+=("${PGDATABASE:-ems}")
fi

SITE_CLAUSE=""
if [[ -n "$SITE_ID" ]]; then
  if ! [[ "$SITE_ID" =~ ^[0-9]+$ ]]; then
    echo "Druhý argument musí být číslo site_id." >&2
    exit 1
  fi
  SITE_CLAUSE="AND r.site_id = ${SITE_ID}::int"
fi

DRY="${DRY_RUN:-0}"

if [[ "$DRY" == "1" ]] || [[ "$DRY" == "true" ]]; then
  echo "DRY_RUN: den $DAY (Europe/Prague)${SITE_ID:+ site_id=$SITE_ID}"
  "${PSQL[@]}" -c "
  with bounds as (
    select
      ('${DAY}'::date::text || ' 00:00:00')::timestamp at time zone 'Europe/Prague' as ts_start,
      (('${DAY}'::date + 1)::text || ' 00:00:00')::timestamp at time zone 'Europe/Prague' as ts_end
  ),
  targets as (
    select fi.run_id, fi.pv_array_id, fi.interval_start
    from ems.forecast_pv_interval fi
    inner join ems.forecast_pv_run r on r.id = fi.run_id
    cross join bounds b
    where fi.interval_start >= b.ts_start
      and fi.interval_start < b.ts_end
      ${SITE_CLAUSE}
  )
  select count(*) as interval_rows_to_delete, count(distinct run_id) as distinct_run_ids
  from targets;
"
  exit 0
fi

echo "Mažu PV forecast intervaly pro den $DAY (Europe/Prague)${SITE_ID:+ site_id=$SITE_ID} …"

"${PSQL[@]}" -c "
begin;

create temporary table _ems_wipe_pv_forecast_targets (
  run_id int not null,
  pv_array_id int not null,
  interval_start timestamptz not null
) on commit drop;

with bounds as (
  select
    ('${DAY}'::date::text || ' 00:00:00')::timestamp at time zone 'Europe/Prague' as ts_start,
    (('${DAY}'::date + 1)::text || ' 00:00:00')::timestamp at time zone 'Europe/Prague' as ts_end
)
insert into _ems_wipe_pv_forecast_targets (run_id, pv_array_id, interval_start)
select fi.run_id, fi.pv_array_id, fi.interval_start
from ems.forecast_pv_interval fi
inner join ems.forecast_pv_run r on r.id = fi.run_id
cross join bounds b
where fi.interval_start >= b.ts_start
  and fi.interval_start < b.ts_end
  ${SITE_CLAUSE};

delete from ems.forecast_accuracy fa
using (select distinct run_id, interval_start from _ems_wipe_pv_forecast_targets) t
where fa.run_id = t.run_id
  and fa.interval_start = t.interval_start;

delete from ems.forecast_pv_interval fi
using _ems_wipe_pv_forecast_targets t
where fi.run_id = t.run_id
  and fi.pv_array_id = t.pv_array_id
  and fi.interval_start = t.interval_start;

delete from ems.forecast_pv_run fr
where fr.id in (select distinct run_id from _ems_wipe_pv_forecast_targets)
  and not exists (
    select 1 from ems.forecast_pv_interval x where x.run_id = fr.id
  );

select
  (select count(*) from _ems_wipe_pv_forecast_targets) as targets_interval_rows,
  (select count(distinct run_id) from _ems_wipe_pv_forecast_targets) as distinct_run_ids_touched;

commit;
"

echo "Hotovo. Spusť forecast job / službu v backendu (Open-Meteo běh), aby se řádky ${DAY} doplnily znovu."