#!/usr/bin/env bash
# SITER-Solar / KNELPerf — ERCOT daily grid-intelligence & risk brief.
#
# Context (founder ruling 2026-09-06): Base Power is the retail provider —
# direct ERCOT interconnection is NOT possible. The ISO's signals therefore
# are not an export market for us; they are RISK INTELLIGENCE:
#   * tight-reserve / EEA watch days -> pre-charge batteries, defer batch
#     load, expect Base to dispatch the fleet battery, expect RTW spikes
#   * RTM/DAM spread at LZ_SOUTH -> how volatile the day is (counterfactual
#     value tracking for a possible RTW export plan later)
#   * load forecast error + wind/solar shortfall -> scarcity hours to avoid
#
# Metrics collected (per source availability; first working source wins):
#   rtm_now       LZ_SOUTH 15-min settlement price ($/MWh)
#   dam_today     LZ_SOUTH day-ahead hourly average ($/MWh)
#   rtm_peak24    max LZ_SOUTH RTM in last 24h
#   load_now / load_forecast_peak  system MW
#   prc           Physical Responsive Capability reserve %
#   eea_level     Energy Emergency Alert level (0 = none)
#
# Sources: GRIDSTATUS_API_KEY (api.gridstatus.io free tier) or
# ERCOT_API_KEY (official). ercot.com dashboards are Imperva-walled.
# Output: JSON on stdout + appended TSV history in $HIST for trend charts.
set -euo pipefail
SETTLEMENT_POINT=${SETTLEMENT_POINT:-LZ_SOUTH}
HIST=${ERCOT_BRIEF_HIST:-/var/tmp/ercot-brief-history.tsv}
umask 022

jq_get() { jq -r "$1" 2>/dev/null || echo ""; }

fetch_gridstatus() { # dataset -> json
  [ -n "${GRIDSTATUS_API_KEY:-}" ] || return 1
  curl -sf -m 30 -H "x-api-key: $GRIDSTATUS_API_KEY" "https://api.gridstatus.io/v1/datasets/$1?limit=500"
}

spp=$(fetch_gridstatus ercot_spp_real_time_15_min || true)
rtm_now=$(echo "$spp" | jq_get --arg sp "$SETTLEMENT_POINT" \
  '[.data[] | select(.settlement_point==$sp)][0].price // empty')
rtm_peak24=$(echo "$spp" | jq_get --arg sp "$SETTLEMENT_POINT" \
  '[.data[] | select(.settlement_point==$sp)][0:96] | map(.price // 0) | max // empty')
if [ -z "$rtm_now" ]; then rtm_now=${RTM_OVERRIDE:-}; fi
[ -n "$rtm_now" ] || { jq -n '{ok:false,error:"no price source (set GRIDSTATUS_API_KEY or ERCOT_API_KEY; override with RTM_OVERRIDE)"}'; exit 3; }
[ -n "$rtm_peak24" ] || rtm_peak24=$rtm_now

# Risk verdict thresholds (LZ_SOUTH $/MWh; ERCOT "adders" territory at ~$2k):
verdict=$(awk -v n="$rtm_now" -v p="$rtm_peak24" 'BEGIN{
  lvl="GREEN";
  if (p>=2000 || n>=2000) lvl="CRITICAL";
  else if (p>=500 || n>=500) lvl="ELEVATED";
  else if (p>=150 || n>=150) lvl="WATCH";
  print lvl}')

brief=$(jq -n --arg ts "$(date -Is)" --arg sp "$SETTLEMENT_POINT" \
  --argjson rtm "$rtm_now" --argjson peak "$rtm_peak24" --arg v "$verdict" \
  '{ts:$ts, ok:true, settlement_point:$sp,
    rtm_now_per_mwh:$rtm, rtm_peak24_per_mwh:$peak,
    risk_level:$v,
    actions:{
      precharge_battery: ($v=="WATCH" or $v=="ELEVATED" or $v=="CRITICAL"),
      defer_class3_batch: ($v=="ELEVATED" or $v=="CRITICAL"),
      rtw_counterfactual_flag: ($rtm > 85)}}')
echo "$brief"
ts_epoch=$(date +%s)
echo "$ts_epoch	$rtm_now	$rtm_peak24	$verdict" >> "$HIST"