#!/usr/bin/env bash
# save-patches.sh — 将 Antigravity 自定义改动导出为 patch 文件
# 用法: ./tools/scripts/save-patches.sh [输出目录]
set -euo pipefail

REPO_ROOT="$(cd "$(dirname "$0")/../.." && pwd)"
OUTPUT_DIR="${1:-$REPO_ROOT/tools/patches}"
UPSTREAM="origin/main"

cd "$REPO_ROOT"

# 检查是否有新的 upstream commits
DIVERGED=$(git log --oneline "$UPSTREAM"..HEAD 2>/dev/null | wc -l | tr -d ' ')
if [ "$DIVERGED" -eq 0 ]; then
    echo "[save-patches] 没有领先 upstream 的 commits，无需保存。"
    exit 0
fi

mkdir -p "$OUTPUT_DIR"

# 导出 patches
git format-patch "$UPSTREAM"..HEAD --output-directory "$OUTPUT_DIR" --no-stat

COUNT=$(ls "$OUTPUT_DIR"/*.patch 2>/dev/null | wc -l | tr -d ' ')
echo "[save-patches] ✅ 已导出 $COUNT 个 patch 到 $OUTPUT_DIR/"
echo ""
echo "恢复方法（在全新 upstream checkout 上）："
echo "  git am $OUTPUT_DIR/*.patch"
echo "  # 或逐一应用："
echo "  for p in $OUTPUT_DIR/*.patch; do git am \"\$p\" || git am --skip; done"