set -eux

export branch=fix-pymongo-history
# Commit prior to PYTHON-4264 
BASE_COMMIT=da03da34c6498378d6a9a7f5c9c5c19cd579d9b1

pymongo_files=("client_session.py" "encryption.py" "auth_oidc.py" \
       "collection.py" "pool.py" "command_cursor.py" "mongo_client.py" \
       "change_stream.py" "cursor.py" \
       "auth.py" "database.py")

git checkout master
git branch -D $branch || true
git checkout -b $branch
git checkout master
git branch -D restore-file || true
git checkout -b restore-file $BASE_COMMIT

function move() {
    local name=$1
    local source=$2
    local target=$3
    echo $target
    # The important rename commit.
    git mv $source $target 
    git add $target
    git commit -m "Rename $source to $target"
    git checkout HEAD~1 $source
    git add $source
    # Sync files with latest state.
    git checkout master $target
    git checkout master $source
    git add $target $source
    git commit -m "Sync $name to master"
}

for name in "${pymongo_files[@]}"
do
    mkdir -p pymongo/synchronous
    source="pymongo/$name"
    target="pymongo/synchronous/$name"
    move $name $source $target
done

mkdir -p gridfs/synchronous
name="grid_file.py"
source="gridfs/$name"
target="gridfs/synchronous/$name"
move $name $source $target

# # There should not be any conflicts or changes to target file in this commit!
git merge -X theirs $branch -m "Merge $branch"
# # The missing "fast-forward merge" feature on GitHub.
git checkout $branch && git merge --ff-only restore-file