--
-- Licensed to the Apache Software Foundation (ASF) under one or more
-- contributor license agreements.  See the NOTICE file distributed with
-- this work for additional information regarding copyright ownership.
-- The ASF licenses this file to You under the Apache License, Version 2.0
-- (the "License"); you may not use this file except in compliance with
-- the License.  You may obtain a copy of the License at
--
--     http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing, software
-- distributed under the License is distributed on an "AS IS" BASIS,
-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-- See the License for the specific language governing permissions and
-- limitations under the License.
--
local core    = require("apisix.core")
local ngx_time = ngx.time


local _M = {}


local function inject_timestamp(conf, prev_conf, patch_conf)
    if not conf.create_time then
        if prev_conf and prev_conf.node.value.create_time then
            conf.create_time = prev_conf.node.value.create_time
        else
            -- As we don't know existent data's create_time, we have to pretend
            -- they are created now.
            conf.create_time = ngx_time()
        end
    end

    -- For PATCH request, the modification is passed as 'patch_conf'
    if not conf.update_time or (patch_conf and patch_conf.update_time == nil) then
        conf.update_time = ngx_time()
    end
end
_M.inject_timestamp = inject_timestamp


function _M.inject_conf_with_prev_conf(kind, key, conf)
    local res, err = core.etcd.get(key)
    if not res or (res.status ~= 200 and res.status ~= 404) then
        core.log.error("failed to get " .. kind .. "[", key, "] from etcd: ", err or res.status)
        return nil, err
    end

    if res.status == 404 then
        inject_timestamp(conf)
    else
        inject_timestamp(conf, res.body)
    end

    return true
end


return _M