--
-- 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 get_routes = require("apisix.router").http_routes
local get_stream_routes = require("apisix.router").stream_routes
local apisix_upstream = require("apisix.upstream")
local resource = require("apisix.admin.resource")
local schema_plugin = require("apisix.admin.plugins").check_schema
local tostring = tostring
local ipairs = ipairs
local type = type
local loadstring = loadstring


local function check_conf(id, conf, need_id, schema)
    local ok, err = core.schema.check(schema, conf)
    if not ok then
        return nil, {error_msg = "invalid configuration: " .. err}
    end

    if need_id and not id then
        return nil, {error_msg = "wrong type of service id"}
    end

    local upstream_conf = conf.upstream
    if upstream_conf then
        local ok, err = apisix_upstream.check_upstream_conf(upstream_conf)
        if not ok then
            return nil, {error_msg = err}
        end
    end

    local upstream_id = conf.upstream_id
    if upstream_id then
        local key = "/upstreams/" .. upstream_id
        local res, err = core.etcd.get(key)
        if not res then
            return nil, {error_msg = "failed to fetch upstream info by "
                                     .. "upstream id [" .. upstream_id .. "]: "
                                     .. err}
        end

        if res.status ~= 200 then
            return nil, {error_msg = "failed to fetch upstream info by "
                                     .. "upstream id [" .. upstream_id .. "], "
                                     .. "response code: " .. res.status}
        end
    end

    if conf.plugins then
        local ok, err = schema_plugin(conf.plugins)
        if not ok then
            return nil, {error_msg = err}
        end
    end

    if conf.script then
        local obj, err = loadstring(conf.script)
        if not obj then
            return nil, {error_msg = "failed to load 'script' string: "
                                     .. err}
        end

        if type(obj()) ~= "table" then
            return nil, {error_msg = "'script' should be a Lua object"}
        end
    end

    return true
end


local function delete_checker(id)
    local routes, routes_ver = get_routes()
    core.log.info("routes: ", core.json.delay_encode(routes, true))
    core.log.info("routes_ver: ", routes_ver)
    if routes_ver and routes then
        for _, route in ipairs(routes) do
            if type(route) == "table" and route.value
               and route.value.service_id
               and tostring(route.value.service_id) == id then
                return 400, {error_msg = "can not delete this service directly,"
                                         .. " route [" .. route.value.id
                                         .. "] is still using it now"}
            end
        end
    end

    local stream_routes, stream_routes_ver = get_stream_routes()
    core.log.info("stream_routes: ", core.json.delay_encode(stream_routes, true))
    core.log.info("stream_routes_ver: ", stream_routes_ver)
    if stream_routes_ver and stream_routes then
        for _, route in ipairs(stream_routes) do
            if type(route) == "table" and route.value
               and route.value.service_id
               and tostring(route.value.service_id) == id then
                return 400, {error_msg = "can not delete this service directly,"
                                         .. " stream_route [" .. route.value.id
                                         .. "] is still using it now"}
            end
        end
    end

    return nil, nil
end


return resource.new({
    name = "services",
    kind = "service",
    schema = core.schema.service,
    checker = check_conf,
    delete_checker = delete_checker
})