#!/bin/bash
# ============================================================================
# 向量记忆增量备份脚本
# 策略：每日一个快照，通过 rsync --link-dest 指向前一天快照
# 文件内容未变时使用硬链接（不占额外空间）
# 保留最近 14 个每日快照
# ============================================================================

set -e

SOURCE="$HOME/.openclaw/memory/main.sqlite"
BACKUP_DIR="$HOME/openclaw-backup/vector_memory/snapshots"
TODAY=$(date +%Y%m%d)
YESTERDAY=$(date -d "yesterday" +%Y%m%d)
SNAPSHOT_TODAY="$BACKUP_DIR/$TODAY"
SNAPSHOT_YESTERDAY="$BACKUP_DIR/$YESTERDAY"

mkdir -p "$BACKUP_DIR"

log() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] [vector_backup] $1"
}

# ---- 检查源文件 ----
if [ ! -f "$SOURCE" ]; then
    log "ERROR: 源文件不存在 $SOURCE"
    exit 1
fi

# ---- 执行增量/全量备份 ----
if [ -n "$SNAPSHOT_YESTERDAY" ] && [ -d "$SNAPSHOT_YESTERDAY" ]; then
    # 有昨天快照：增量硬链接
    mkdir -p "$SNAPSHOT_TODAY"
    rsync -a --link-dest="$SNAPSHOT_YESTERDAY" "$SOURCE" "$SNAPSHOT_TODAY/main.sqlite"
    log "增量备份完成 → $SNAPSHOT_TODAY/main.sqlite ($(du -h "$SNAPSHOT_TODAY/main.sqlite" | cut -f1))"
else
    # 无昨天快照（首次或跨天后首次）：全量
    mkdir -p "$SNAPSHOT_TODAY"
    cp "$SOURCE" "$SNAPSHOT_TODAY/main.sqlite"
    log "全量备份完成 → $SNAPSHOT_TODAY/main.sqlite ($(du -h "$SNAPSHOT_TODAY/main.sqlite" | cut -f1))"
fi

# ---- 清理 14 天前的快照 ----
SNAP_COUNT=$(ls -d "$BACKUP_DIR"/20* 2>/dev/null | wc -l)
if [ "$SNAP_COUNT" -gt 14 ]; then
    ls -dt "$BACKUP_DIR"/20* | tail -n +15 | xargs -r rm -rf
    log "已清理 14 天前的旧快照"
fi

# ---- 打印当前快照列表 ----
log "当前每日快照（共 $SNAP_COUNT 个）:"
for d in $(ls -dt "$BACKUP_DIR"/20* 2>/dev/null); do
    log "  $(basename $d) ($(du -sh "$d" | cut -f1))"
done
log "总磁盘占用: $(du -sh "$BACKUP_DIR" | cut -f1)"