#!/bin/bash
# AOS Backup Script (PRD §5.7: backup container)
# Usage: ./deploy/backup.sh
# Creates a timestamped SQLite backup + SHA-256 checksum.
set -eu

DB_PATH="${DATABASE_URL:-file:/home/z/my-project/db/custom.db}"
DB_FILE="${DB_PATH#file:}"
BACKUP_DIR="${BACKUP_DIR:-/home/z/my-project/db/backups}"
RETENTION_DAYS="${BACKUP_RETENTION_DAYS:-30}"
TIMESTAMP=$(date +%Y%m%d_%H%M%S)
BACKUP_FILE="$BACKUP_DIR/aos_$TIMESTAMP.db"

mkdir -p "$BACKUP_DIR"

echo "=== AOS Backup ==="
echo "  DB: $DB_FILE"
echo "  Backup: $BACKUP_FILE"

# SQLite backup (online, consistent)
if command -v sqlite3 >/dev/null 2>&1; then
    sqlite3 "$DB_FILE" ".backup '$BACKUP_FILE'"
elif command -v cp >/dev/null 2>&1; then
    cp "$DB_FILE" "$BACKUP_FILE"
else
    echo "ERROR: Neither sqlite3 nor cp available"
    exit 1
fi

# SHA-256 checksum
sha256sum "$BACKUP_FILE" > "$BACKUP_FILE.sha256"
echo "  Checksum: $(cat "$BACKUP_FILE.sha256" | cut -d' ' -f1 | head -c 32)..."

# File listing + sizes
echo ""
echo "=== Recent backups ==="
ls -lh "$BACKUP_DIR"/aos_*.db 2>/dev/null | tail -5

# Cleanup old backups
echo ""
echo "=== Cleanup (>$RETENTION_DAYS days) ==="
deleted=$(find "$BACKUP_DIR" -name "aos_*.db" -mtime +$RETENTION_DAYS -print -delete 2>/dev/null | wc -l)
deleted_sha=$(find "$BACKUP_DIR" -name "aos_*.db.sha256" -mtime +$RETENTION_DAYS -print -delete 2>/dev/null | wc -l)
echo "  Deleted: $deleted backups + $deleted_sha checksums"

echo ""
echo "=== Backup complete ==="