#!/usr/bin/env bash
# build-oracle.sh — generate the regression oracle snapshot for the calendar
# engine by fetching the authoritative General Roman Calendar from calapi
# (calendarium-romanum) month by month, 2020-2040.
#
# NOT run by `go test`. Requires network + curl + jq. Run from the repo root:
#   scripts/build-oracle.sh
# Writes internal/calendar/testdata/oracle-2020-2040.json as
#   { "YYYY-MM-DD": {"season": "...", "rank_num": N.N}, ... }
# where season/rank_num are the top celebration's (celebrations[0]).
set -euo pipefail

base="http://calapi.inadiutorium.cz/api/v0/en/calendars/general-en"
out="internal/calendar/testdata/oracle-2020-2040.json"
mkdir -p "$(dirname "$out")"
tmp="$(mktemp)"

echo "{" > "$tmp"
first=1
for y in $(seq 2020 2040); do
  for m in $(seq 1 12); do
    month_json="$(curl -sf "$base/$y/$m")"
    # emit  "date": {"season":..., "rank_num":...}  for each day, comma-separated
    rows="$(printf '%s' "$month_json" | jq -r '.[] | "\(.date)\t\(.season)\t\(.celebrations[0].rank_num)"')"
    while IFS=$'\t' read -r date season rank; do
      [ -n "$date" ] || continue
      if [ "$first" -eq 1 ]; then first=0; else printf ",\n" >> "$tmp"; fi
      printf '  "%s": {"season": "%s", "rank_num": %s}' "$date" "$season" "$rank" >> "$tmp"
    done <<< "$rows"
  done
  echo "  ...$y done" >&2
done
printf "\n}\n" >> "$tmp"
mv "$tmp" "$out"
echo "wrote $out" >&2