#!/usr/bin/env bash
set -euo pipefail

# ============================================
# SiYuan 备份脚本
# 备份工作空间数据 + 配置文件
# ============================================

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$SCRIPT_DIR"

# 加载配置
if [ -f .env ]; then
    sed -i 's/\r$//' .env
    set -a; source .env; set +a
else
    echo "[ERROR] .env 文件不存在，请先运行 deploy.sh" >&2
    exit 1
fi

# ===== 配置 =====
DATA_DIR="${SIYUAN_DATA_DIR:-/data/siyuan/workspace}"
BACKUP_BASE="${BACKUP_DIR:-/var/backups/siyuan}"
TIMESTAMP=$(date +%Y%m%d_%H%M%S)
BACKUP_DIR_FULL="${BACKUP_BASE}/${TIMESTAMP}"
RETENTION_DAYS=30

echo "========== SiYuan 备份 =========="
echo "时间: $(date '+%Y-%m-%d %H:%M:%S')"
echo "数据目录: $DATA_DIR"
echo "备份目录: $BACKUP_DIR_FULL"
echo ""

mkdir -p "$BACKUP_DIR_FULL"

# ===== 备份工作空间数据 =====
echo "[1/3] 备份 SiYuan 工作空间..."
if [ -d "$DATA_DIR" ]; then
    tar czf "$BACKUP_DIR_FULL/siyuan-workspace.tar.gz" -C "$(dirname "$DATA_DIR")" "$(basename "$DATA_DIR")"
    echo "  ✓ 工作空间已备份"
else
    echo "  ⚠ 数据目录不存在: $DATA_DIR"
fi

# ===== 备份 docker-compose 和配置 =====
echo "[2/3] 备份部署配置..."
tar czf "$BACKUP_DIR_FULL/siyuan-config.tar.gz" \
    -C "$SCRIPT_DIR" \
    docker-compose.yml .env nginx/ 2>/dev/null || true
echo "  ✓ 配置已备份"

# ===== 清理旧备份 =====
echo "[3/3] 清理 ${RETENTION_DAYS} 天前的旧备份..."
find "$BACKUP_BASE" -maxdepth 1 -type d -mtime +${RETENTION_DAYS} -exec rm -rf {} \; 2>/dev/null || true
echo "  ✓ 旧备份已清理"

# ===== 汇总 =====
echo ""
echo "========== 备份完成 =========="
TOTAL_SIZE=$(du -sh "$BACKUP_DIR_FULL" | cut -f1)
echo "备份位置: $BACKUP_DIR_FULL"
echo "备份大小: $TOTAL_SIZE"
echo ""
echo "备份内容:"
ls -lh "$BACKUP_DIR_FULL/"
echo ""
echo "恢复方法:"
echo "  cd $SCRIPT_DIR && docker compose down"
echo "  tar xzf $BACKUP_DIR_FULL/siyuan-workspace.tar.gz -C $(dirname "$DATA_DIR")"
echo "  chown -R ${SIYUAN_PUID:-1000}:${SIYUAN_PGID:-1000} $DATA_DIR"
echo "  cd $SCRIPT_DIR && docker compose up -d"