#!/bin/bash
# Hermes Sync Script - 同步记忆和技能到 Gitea
# 用法: ./sync.sh [local|pull|push|status]

set -e

HERMES_HOME="${HERMES_HOME:-$HOME/.hermes}"
SYNC_DIR="/root/hermes-sync-tmp"
BRANCH_NAME="$(hostname)"
GITEA_REMOTE="origin"
COMMIT_MSG="Sync $(date '+%Y-%m-%d %H:%M')"

# 颜色输出
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m'

log() { echo -e "${GREEN}[$(date '+%H:%M:%S')]${NC} $1"; }
warn() { echo -e "${YELLOW}[$(date '+%H:%M:%S')] WARNING:${NC} $1"; }
error() { echo -e "${RED}[$(date '+%H:%M:%S')] ERROR:${NC} $1"; }

# 同步函数 - 从远程拉取最新记忆和技能
pull_changes() {
    log "Pulling latest changes from remote..."
    cd "$SYNC_DIR"
    
    git fetch "$GITEA_REMOTE" 2>/dev/null || warn "Fetch failed (may be empty repo)"
    
    # 尝试合并远程更改
    if git rev-parse "$GITEA_REMOTE/$BRANCH_NAME" >/dev/null 2>&1; then
        if git show-ref --quiet -- HEAD 2>/dev/null && ! git diff --quiet "$GITEA_REMOTE/$BRANCH_NAME" HEAD 2>/dev/null; then
            log "Merging remote changes..."
            git merge "$GITEA_REMOTE/$BRANCH_NAME" --no-edit || {
                warn "Merge conflict detected, attempting auto-resolve..."
                # 自动解决：ours 优先（保留本地记忆）
                git checkout --ours memories/ skills/ 2>/dev/null || true
                git add memories/ skills/
                git commit -m "Auto-resolved merge conflict at $(date)"
            }
        else
            log "Already up to date"
        fi
    fi
    
    # 如果本地分支不存在，基于远程创建
    if ! git rev-parse "$BRANCH_NAME" >/dev/null 2>&1; then
        if git rev-parse "$GITEA_REMOTE/$BRANCH_NAME" >/dev/null 2>&1; then
            git checkout -b "$BRANCH_NAME" "$GITEA_REMOTE/$BRANCH_NAME"
        fi
    fi
    
    # 复制到 hermes 目录
    rsync -a --delete "$SYNC_DIR/memories/" "$HERMES_HOME/memories/" 2>/dev/null || {
        mkdir -p "$HERMES_HOME/memories/"
        cp -r "$SYNC_DIR/memories/"* "$HERMES_HOME/memories/" 2>/dev/null || true
    }
    
    # 技能目录用 rsync 合并（不删除本地独有的）
    rsync -a --delete "$SYNC_DIR/skills/" "$HERMES_HOME/skills/" 2>/dev/null || {
        cp -r "$SYNC_DIR/skills/"* "$HERMES_HOME/skills/" 2>/dev/null || true
    }
    
    log "Pull complete. Memories and skills updated."
}

# 推送本地更改到远程
push_changes() {
    log "Pushing local changes to remote..."
    cd "$SYNC_DIR"
    
    # 确保分支存在
    if ! git rev-parse "$BRANCH_NAME" >/dev/null 2>&1; then
        git checkout -b "$BRANCH_NAME"
    fi
    
    # 复制 hermes 内容到同步目录
    mkdir -p "$SYNC_DIR/memories" "$SYNC_DIR/skills"
    rsync -a "$HERMES_HOME/memories/" "$SYNC_DIR/memories/" 2>/dev/null || true
    rsync -a "$HERMES_HOME/skills/" "$SYNC_DIR/skills/" 2>/dev/null || true
    
    # 检查是否有更改
    if git diff --quiet && git diff --cached --quiet; then
        log "No changes to push"
        return 0
    fi
    
    git add -A
    git commit -m "$COMMIT_MSG"
    git push "$GITEA_REMOTE" "$BRANCH_NAME" --force || {
        error "Push failed! Check credentials and network."
        return 1
    }
    
    log "Push complete. Your changes are now synced."
}

# 双向同步
sync_bidirectional() {
    log "Starting bidirectional sync..."
    pull_changes
    push_changes
}

# 查看状态
show_status() {
    cd "$SYNC_DIR"
    echo "=== Hermes Sync Status ==="
    echo "Branch: $BRANCH_NAME"
    echo ""
    echo "Local changes:"
    git status -s 2>/dev/null || echo "  (clean)"
    echo ""
    echo "Remote changes:"
    git fetch "$GITEA_REMOTE" 2>/dev/null
    if git rev-parse "$GITEA_REMOTE/$BRANCH_NAME" >/dev/null 2>&1; then
        BEHIND=$(git rev-list --count "$BRANCH_NAME..$GITEA_REMOTE/$BRANCH_NAME" 2>/dev/null || echo "?")
        AHEAD=$(git rev-list --count "$GITEA_REMOTE/$BRANCH_NAME..$BRANCH_NAME" 2>/dev/null || echo "?")
        echo "  Behind remote: $BEHIND commits"
        echo "  Ahead of remote: $AHEAD commits"
    else
        echo "  No remote branch yet"
    fi
    echo ""
    echo "Last sync:"
    git log -1 --format="%cr (%s)" 2>/dev/null || echo "  Never committed"
}

# 主逻辑
case "${1:-status}" in
    pull)
        pull_changes
        ;;
    push)
        push_changes
        ;;
    sync|bidirectional)
        sync_bidirectional
        ;;
    status)
        show_status
        ;;
    *)
        echo "Usage: $0 {pull|push|sync|status}"
        echo "  pull        - Pull from remote to local"
        echo "  push        - Push local to remote"
        echo "  sync        - Pull then push (bidirectional)"
        echo "  status      - Show sync status"
        exit 1
        ;;
esac