#!/usr/bin/env bash

set -Eeuo pipefail

cd /workspace

database_url="${DATABASE_URL:-}"
geofabrik_dir="${WATERMAPS_GEOFABRIK_DIR:-/workspace/data/geofabrik}"
marker_file="${WATERMAPS_MARINE_MARKER_PATH:-/workspace/data/local/.marine-features.ready}"
temporary_root="${TMPDIR:-/tmp}"
pbf_paths=(
  "$geofabrik_dir/germany-latest.osm.pbf"
  "$geofabrik_dir/netherlands-latest.osm.pbf"
)

if [[ -z "$database_url" ]]; then
  printf 'Fehler: DATABASE_URL ist für den Marine-Feature-Import erforderlich.\n' >&2
  exit 1
fi

if [[ ! -x /workspace/scripts/import-geofabrik.sh ]]; then
  printf 'Fehler: scripts/import-geofabrik.sh fehlt oder ist nicht ausführbar.\n' >&2
  exit 1
fi

mkdir -p "$(dirname "$marker_file")" "$temporary_root"
export TMPDIR="$temporary_root"

declare -A source_checksums
for pbf_path in "${pbf_paths[@]}"; do
  if [[ ! -s "$pbf_path" ]]; then
    printf 'Fehler: Geofabrik-Snapshot fehlt oder ist leer: %s\n' "$pbf_path" >&2
    exit 1
  fi

  checksum_file="${pbf_path}.md5"
  if [[ ! -s "$checksum_file" ]]; then
    printf 'Fehler: Geofabrik-Prüfsumme fehlt: %s\n' "$checksum_file" >&2
    exit 1
  fi

  expected_checksum="$(awk 'NR == 1 { print tolower($1) }' "$checksum_file")"
  if [[ ! "$expected_checksum" =~ ^[0-9a-f]{32}$ ]]; then
    printf 'Fehler: Ungültige Geofabrik-Prüfsumme in %s\n' "$checksum_file" >&2
    exit 1
  fi

  actual_checksum="$(md5sum "$pbf_path" | awk '{ print $1 }')"
  if [[ "$actual_checksum" != "$expected_checksum" ]]; then
    printf 'Fehler: Geofabrik-Snapshot stimmt nicht mit seiner Prüfsumme überein: %s\n' "$pbf_path" >&2
    exit 1
  fi
  source_checksums["$(basename "$pbf_path" -latest.osm.pbf)"]="$actual_checksum"
done

# Every imported OSM row receives updated_at=now(). The shared database
# timestamp lets us remove disappeared OSM objects only after both regional
# imports completed and passed the sanity checks. Other sources such as EuRIS
# and facility-website enrichments are deliberately preserved.
import_started_epoch="$(
  psql "$database_url" \
    --no-psqlrc \
    --tuples-only \
    --no-align \
    --set ON_ERROR_STOP=1 \
    --command "SELECT extract(epoch FROM clock_timestamp());"
)"
import_started_epoch="${import_started_epoch//[[:space:]]/}"
if [[ ! "$import_started_epoch" =~ ^[0-9]+([.][0-9]+)?$ ]]; then
  printf 'Fehler: Datenbank lieferte keinen gültigen Importzeitpunkt.\n' >&2
  exit 1
fi

for pbf_path in "${pbf_paths[@]}"; do
  printf 'Importiere Marine-Features aus %s\n' "$(basename "$pbf_path")"
  DATABASE_URL="$database_url" /workspace/scripts/import-geofabrik.sh "$pbf_path"
done

fresh_counts="$(
  psql "$database_url" \
    --no-psqlrc \
    --tuples-only \
    --no-align \
    --field-separator '|' \
    --set ON_ERROR_STOP=1 \
    --command "
      SELECT
        count(*)::bigint,
        count(*) FILTER (WHERE layer = 'harbours')::bigint,
        count(*) FILTER (WHERE layer = 'locks')::bigint,
        count(*) FILTER (WHERE layer = 'bridges')::bigint
      FROM marine_features
      WHERE source = 'osm'
        AND updated_at >= to_timestamp($import_started_epoch);
    "
)"
fresh_counts="${fresh_counts//[[:space:]]/}"
IFS='|' read -r fresh_total fresh_harbours fresh_locks fresh_bridges <<<"$fresh_counts"
for count in "$fresh_total" "$fresh_harbours" "$fresh_locks" "$fresh_bridges"; do
  if [[ ! "$count" =~ ^[1-9][0-9]*$ ]]; then
    printf 'Fehler: Der neue OSM-Import enthält keine vollständigen Hafen-/Schleusen-/Brückendaten.\n' >&2
    exit 1
  fi
done

psql "$database_url" \
  --no-psqlrc \
  --set ON_ERROR_STOP=1 \
  --command "
    BEGIN;
    DELETE FROM marine_features
    WHERE source = 'osm'
      AND updated_at < to_timestamp($import_started_epoch);
    DELETE FROM marine_fairway_edges
    WHERE source = 'osm'
      AND updated_at < to_timestamp($import_started_epoch);
    COMMIT;
    ANALYZE marine_features;
    ANALYZE marine_fairway_edges;
  "

final_counts="$(
  psql "$database_url" \
    --no-psqlrc \
    --tuples-only \
    --no-align \
    --field-separator '|' \
    --set ON_ERROR_STOP=1 \
    --command "
      SELECT
        count(*)::bigint,
        count(*) FILTER (WHERE layer = 'harbours')::bigint,
        count(*) FILTER (WHERE layer = 'locks')::bigint,
        count(*) FILTER (WHERE layer = 'bridges')::bigint
      FROM marine_features
      WHERE source = 'osm';
    "
)"
final_counts="${final_counts//[[:space:]]/}"
IFS='|' read -r total_osm_features harbour_count lock_count bridge_count <<<"$final_counts"

temporary_marker="$(mktemp "$(dirname "$marker_file")/.marine-features-ready.XXXXXX")"
{
  printf 'format_version=1\n'
  printf 'generated_at=%s\n' "$(date --utc +%Y-%m-%dT%H:%M:%SZ)"
  printf 'source=germany+netherlands\n'
  printf 'germany_md5=%s\n' "${source_checksums[germany]}"
  printf 'netherlands_md5=%s\n' "${source_checksums[netherlands]}"
  printf 'total_osm_features=%s\n' "$total_osm_features"
  printf 'harbour_count=%s\n' "$harbour_count"
  printf 'lock_count=%s\n' "$lock_count"
  printf 'bridge_count=%s\n' "$bridge_count"
} >"$temporary_marker"
chmod 0644 "$temporary_marker"
mv -f "$temporary_marker" "$marker_file"

printf 'Marine-Features sind bereit: %s OSM-Objekte (%s Häfen, %s Schleusen, %s Brücken)\n' \
  "$total_osm_features" "$harbour_count" "$lock_count" "$bridge_count"