#!/bin/sh
set -eu

# Read-only preflight for the legacy SQLite -> native WeKnora migration.
# It never writes to the source database and never imports data. The output is
# intentionally small enough to attach to a migration review.
DB_PATH=${LEGACY_DB_PATH:-/Volumes/Extreme\ SSD/yawan-storage/yawan-workbench/server/data/workspace.db}
if [ ! -f "$DB_PATH" ]; then
  DB_PATH=${LEGACY_DB_PATH_FALLBACK:-/Users/macclaw/Desktop/yawan-workbench/server/data-dev/workspace.db}
fi
if [ ! -f "$DB_PATH" ]; then
  echo "legacy database not found; set LEGACY_DB_PATH" >&2
  exit 2
fi

command -v sqlite3 >/dev/null 2>&1 || { echo "sqlite3 is required" >&2; exit 2; }

sha=$(shasum -a 256 "$DB_PATH" | awk '{print $1}')
size=$(wc -c < "$DB_PATH" | tr -d ' ')
integrity=$(sqlite3 "$DB_PATH" 'PRAGMA integrity_check;' | tr '\n' ' ' | sed 's/[[:space:]]*$//')
if [ "$integrity" != "ok" ]; then
  echo "legacy database integrity check failed: $integrity" >&2
  exit 1
fi

count() {
  table=$1
  # sqlite3 exits non-zero for a missing table; surface that as zero only for
  # optional legacy tables so an audit can run against older snapshots.
  sqlite3 "$DB_PATH" "SELECT count(*) FROM \"$table\";" 2>/dev/null || echo 0
}

printf '{\n'
printf '  "path": %s,\n' "$(printf '%s' "$DB_PATH" | awk '{gsub(/\\/, "\\\\"); gsub(/"/, "\\\""); printf "\"%s\"", $0}')"
printf '  "bytes": %s,\n' "$size"
printf '  "sha256": "%s",\n' "$sha"
printf '  "integrity": "ok",\n'
printf '  "counts": {\n'
tables='appuser knowledgebase knowledgefile knowledgecategory agent agentskill agentskillbinding canvas trainingmap segment digitalhuman memory knowledgeusage pointaccount pointtransaction auditlog systemlog'
first=1
for table in $tables; do
  [ "$first" -eq 1 ] || printf ',\n'
  first=0
  printf '    "%s": %s' "$table" "$(count "$table")"
done
printf '\n  }\n}\n'