--
-- 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 ver = require("apisix.core.version")
local etcd = require("apisix.cli.etcd")
local util = require("apisix.cli.util")
local file = require("apisix.cli.file")
local ngx_tpl = require("apisix.cli.ngx_tpl")
local profile = require("apisix.core.profile")
local template = require("resty.template")
local argparse = require("argparse")
local pl_path = require("pl.path")
local jsonschema = require("jsonschema")

local stderr = io.stderr
local ipairs = ipairs
local pairs = pairs
local print = print
local type = type
local tostring = tostring
local tonumber = tonumber
local io_open = io.open
local popen = io.popen
local execute = os.execute
local table_insert = table.insert
local getenv = os.getenv
local max = math.max
local floor = math.floor
local str_find = string.find
local str_byte = string.byte
local str_sub = string.sub


local _M = {}


local function help()
    print([[
Usage: apisix [action] <argument>

help:       show this message, then exit
init:       initialize the local nginx.conf
init_etcd:  initialize the data of etcd
start:      start the apisix server
stop:       stop the apisix server
restart:    restart the apisix server
reload:     reload the apisix server
version:    print the version of apisix
]])
end


local function check_version(cur_ver_s, need_ver_s)
    local cur_vers = util.split(cur_ver_s, [[.]])
    local need_vers = util.split(need_ver_s, [[.]])
    local len = max(#cur_vers, #need_vers)

    for i = 1, len do
        local cur_ver = tonumber(cur_vers[i]) or 0
        local need_ver = tonumber(need_vers[i]) or 0
        if cur_ver > need_ver then
            return true
        end

        if cur_ver < need_ver then
            return false
        end
    end

    return true
end


local function get_openresty_version()
    local str = "nginx version: openresty/"
    local ret = util.execute_cmd("openresty -v 2>&1")
    local pos = str_find(ret, str, 1, true)
    if pos then
        return str_sub(ret, pos + #str)
    end

    str = "nginx version: nginx/"
    pos = str_find(ret, str, 1, true)
    if pos then
        return str_sub(ret, pos + #str)
    end
end


local function local_dns_resolver(file_path)
    local file, err = io_open(file_path, "rb")
    if not file then
        return false, "failed to open file: " .. file_path .. ", error info:" .. err
    end

    local dns_addrs = {}
    for line in file:lines() do
        local addr, n = line:gsub("^nameserver%s+([^%s]+)%s*$", "%1")
        if n == 1 then
            table_insert(dns_addrs, addr)
        end
    end

    file:close()
    return dns_addrs
end
-- exported for test
_M.local_dns_resolver = local_dns_resolver


local function version()
    print(ver['VERSION'])
end


local function get_lua_path(conf)
    -- we use "" as the placeholder to enforce the type to be string
    if conf and conf ~= "" then
        if #conf < 2 then
            -- the shortest valid path is ';;'
            util.die("invalid extra_lua_path/extra_lua_cpath: \"", conf, "\"\n")
        end

        local path = conf
        if path:byte(-1) ~= str_byte(';') then
            path = path .. ';'
        end
        return path
    end

    return ""
end


local config_schema = {
    type = "object",
    properties = {
        apisix = {
            properties = {
                config_center = {
                    enum = {"etcd", "yaml"},
                },
                proxy_protocol = {
                    type = "object",
                    properties = {
                        listen_http_port = {
                            type = "integer",
                        },
                        listen_https_port = {
                            type = "integer",
                        },
                        enable_tcp_pp = {
                            type = "boolean",
                        },
                        enable_tcp_pp_to_upstream = {
                            type = "boolean",
                        },
                    }
                },
                port_admin = {
                    type = "integer",
                },
                https_admin = {
                    type = "boolean",
                },
                stream_proxy = {
                    type = "object",
                    properties = {
                        tcp = {
                            type = "array",
                            minItems = 1,
                            items = {
                                anyOf = {
                                    {
                                        type = "integer",
                                    },
                                    {
                                        type = "string",
                                    },
                                },
                            },
                            uniqueItems = true,
                        },
                        udp = {
                            type = "array",
                            minItems = 1,
                            items = {
                                anyOf = {
                                    {
                                        type = "integer",
                                    },
                                    {
                                        type = "string",
                                    },
                                },
                            },
                            uniqueItems = true,
                        },
                    }
                },
                dns_resolver = {
                    type = "array",
                    minItems = 1,
                    items = {
                        type = "string",
                    }
                },
                dns_resolver_valid = {
                    type = "integer",
                },
                ssl = {
                    type = "object",
                    properties = {
                        ssl_trusted_certificate = {
                            type = "string",
                        }
                    }
                },
            }
        },
        nginx_config = {
            type = "object",
            properties = {
                envs = {
                    type = "array",
                    minItems = 1,
                    items = {
                        type = "string",
                    }
                }
            },
        },
        http = {
            type = "object",
            properties = {
                lua_shared_dicts = {
                    type = "object",
                }
            }
        },
        etcd = {
            type = "object",
            properties = {
                resync_delay = {
                    type = "integer",
                },
                user = {
                    type = "string",
                },
                password = {
                    type = "string",
                },
                tls = {
                    type = "object",
                    properties = {
                        cert = {
                            type = "string",
                        },
                        key = {
                            type = "string",
                        },
                    }
                }
            }
        }
    }
}


local function init(env)
    if env.is_root_path then
        print('Warning! Running apisix under /root is only suitable for '
              .. 'development environments and it is dangerous to do so. '
              .. 'It is recommended to run APISIX in a directory '
              .. 'other than /root.')
    end

    -- read_yaml_conf
    local yaml_conf, err = file.read_yaml_conf(env.apisix_home)
    if not yaml_conf then
        util.die("failed to read local yaml config of apisix: ", err, "\n")
    end

    local validator = jsonschema.generate_validator(config_schema)
    local ok, err = validator(yaml_conf)
    if not ok then
        util.die("failed to validate config: ", err, "\n")
    end

    -- check the Admin API token
    local checked_admin_key = false
    if yaml_conf.apisix.enable_admin and yaml_conf.apisix.allow_admin then
        for _, allow_ip in ipairs(yaml_conf.apisix.allow_admin) do
            if allow_ip == "127.0.0.0/24" then
                checked_admin_key = true
            end
        end
    end

    if yaml_conf.apisix.enable_admin and not checked_admin_key then
        local help = [[

%s
Please modify "admin_key" in conf/config.yaml .

]]
        if type(yaml_conf.apisix.admin_key) ~= "table" or
           #yaml_conf.apisix.admin_key == 0
        then
            util.die(help:format("ERROR: missing valid Admin API token."))
        end

        for _, admin in ipairs(yaml_conf.apisix.admin_key) do
            if type(admin.key) == "table" then
                admin.key = ""
            else
                admin.key = tostring(admin.key)
            end

            if admin.key == "" then
                util.die(help:format("ERROR: missing valid Admin API token."), "\n")
            end

            if admin.key == "edd1c9f034335f136f87ad84b625c8f1" then
                stderr:write(
                    help:format([[WARNING: using fixed Admin API token has security risk.]]),
                    "\n"
                )
            end
        end
    end

    if yaml_conf.apisix.enable_admin and
        yaml_conf.apisix.config_center == "yaml"
    then
        util.die("ERROR: Admin API can only be used with etcd config_center.\n")
    end

    local or_ver = get_openresty_version()
    if or_ver == nil then
        util.die("can not find openresty\n")
    end

    local need_ver = "1.17.3"
    if not check_version(or_ver, need_ver) then
        util.die("openresty version must >=", need_ver, " current ", or_ver, "\n")
    end

    local or_info = util.execute_cmd("openresty -V 2>&1")
    local with_module_status = true
    if or_info and not or_info:find("http_stub_status_module", 1, true) then
        stderr:write("'http_stub_status_module' module is missing in ",
                     "your openresty, please check it out. Without this ",
                     "module, there will be fewer monitoring indicators.\n")
        with_module_status = false
    end

    local enabled_plugins = {}
    for i, name in ipairs(yaml_conf.plugins) do
        enabled_plugins[name] = true
    end

    if enabled_plugins["proxy-cache"] and not yaml_conf.apisix.proxy_cache then
        util.die("missing apisix.proxy_cache for plugin proxy-cache\n")
    end

    -- support multiple ports listen, compatible with the original style
    if type(yaml_conf.apisix.node_listen) == "number" then
        local node_listen = {{port = yaml_conf.apisix.node_listen}}
        yaml_conf.apisix.node_listen = node_listen
    elseif type(yaml_conf.apisix.node_listen) == "table" then
        local node_listen = {}
        for index, value in ipairs(yaml_conf.apisix.node_listen) do
            if type(value) == "number" then
                table_insert(node_listen, index, {port = value})
            elseif type(value) == "table" then
                table_insert(node_listen, index, value)
            end
        end
        yaml_conf.apisix.node_listen = node_listen
    end

    if type(yaml_conf.apisix.ssl.listen_port) == "number" then
        local listen_port = {yaml_conf.apisix.ssl.listen_port}
        yaml_conf.apisix.ssl.listen_port = listen_port
    end

    if yaml_conf.apisix.ssl.ssl_trusted_certificate ~= nil then
        local cert_path = yaml_conf.apisix.ssl.ssl_trusted_certificate
        -- During validation, the path is relative to PWD
        -- When Nginx starts, the path is relative to conf
        -- Therefore we need to check the absolute version instead
        cert_path = pl_path.abspath(cert_path)

        local ok, err = util.is_file_exist(cert_path)
        if not ok then
            util.die(err, "\n")
        end

        yaml_conf.apisix.ssl.ssl_trusted_certificate = cert_path
    end

    local admin_api_mtls = yaml_conf.apisix.admin_api_mtls
    if yaml_conf.apisix.https_admin and
       not (admin_api_mtls and
            admin_api_mtls.admin_ssl_cert and
            admin_api_mtls.admin_ssl_cert ~= "" and
            admin_api_mtls.admin_ssl_cert_key and
            admin_api_mtls.admin_ssl_cert_key ~= "")
    then
        util.die("missing ssl cert for https admin")
    end

    -- enable ssl with place holder crt&key
    yaml_conf.apisix.ssl.ssl_cert = "cert/ssl_PLACE_HOLDER.crt"
    yaml_conf.apisix.ssl.ssl_cert_key = "cert/ssl_PLACE_HOLDER.key"

    local dubbo_upstream_multiplex_count = 32
    if yaml_conf.plugin_attr and yaml_conf.plugin_attr["dubbo-proxy"] then
        local dubbo_conf = yaml_conf.plugin_attr["dubbo-proxy"]
        if tonumber(dubbo_conf.upstream_multiplex_count) >= 1 then
            dubbo_upstream_multiplex_count = dubbo_conf.upstream_multiplex_count
        end
    end

    if yaml_conf.apisix.dns_resolver_valid then
        if tonumber(yaml_conf.apisix.dns_resolver_valid) == nil then
            util.die("apisix->dns_resolver_valid should be a number")
        end
    end

    -- Using template.render
    local sys_conf = {
        lua_path = env.pkg_path_org,
        lua_cpath = env.pkg_cpath_org,
        os_name = util.trim(util.execute_cmd("uname")),
        apisix_lua_home = env.apisix_home,
        with_module_status = with_module_status,
        error_log = {level = "warn"},
        enabled_plugins = enabled_plugins,
        dubbo_upstream_multiplex_count = dubbo_upstream_multiplex_count,
    }

    if not yaml_conf.apisix then
        util.die("failed to read `apisix` field from yaml file")
    end

    if not yaml_conf.nginx_config then
        util.die("failed to read `nginx_config` field from yaml file")
    end

    if util.is_32bit_arch() then
        sys_conf["worker_rlimit_core"] = "4G"
    else
        sys_conf["worker_rlimit_core"] = "16G"
    end

    for k,v in pairs(yaml_conf.apisix) do
        sys_conf[k] = v
    end
    for k,v in pairs(yaml_conf.nginx_config) do
        sys_conf[k] = v
    end

    if yaml_conf.apisix.enable_control then
        if not yaml_conf.apisix.control then
            sys_conf.control_server_addr = "127.0.0.1:9090"
        else
            local ip = yaml_conf.apisix.control.ip
            local port = tonumber(yaml_conf.apisix.control.port)

            if ip == nil then
                ip = "127.0.0.1"
            end

            if not port then
                port = 9090
            end

            sys_conf.control_server_addr = ip .. ":" .. port
        end
    end

    if yaml_conf.plugin_attr.prometheus then
        local prometheus = yaml_conf.plugin_attr.prometheus
        if prometheus.enable_export_server then
            local ip = prometheus.export_addr.ip
            local port = tonumber(prometheus.export_addr.port)

            if ip == nil then
                ip = "127.0.0.1"
            end

            if not port then
                port = 9091
            end

            sys_conf.prometheus_server_addr = ip .. ":" .. port
        end
    end

    local wrn = sys_conf["worker_rlimit_nofile"]
    local wc = sys_conf["event"]["worker_connections"]
    if not wrn or wrn <= wc then
        -- ensure the number of fds is slightly larger than the number of conn
        sys_conf["worker_rlimit_nofile"] = wc + 128
    end

    if sys_conf["enable_dev_mode"] == true then
        sys_conf["worker_processes"] = 1
        sys_conf["enable_reuseport"] = false

    elseif tonumber(sys_conf["worker_processes"]) == nil then
        sys_conf["worker_processes"] = "auto"
    end

    if sys_conf.allow_admin and #sys_conf.allow_admin == 0 then
        sys_conf.allow_admin = nil
    end

    local dns_resolver = sys_conf["dns_resolver"]
    if not dns_resolver or #dns_resolver == 0 then
        local dns_addrs, err = local_dns_resolver("/etc/resolv.conf")
        if not dns_addrs then
            util.die("failed to import local DNS: ", err, "\n")
        end

        if #dns_addrs == 0 then
            util.die("local DNS is empty\n")
        end

        sys_conf["dns_resolver"] = dns_addrs
    end

    local env_worker_processes = getenv("APISIX_WORKER_PROCESSES")
    if env_worker_processes then
        sys_conf["worker_processes"] = floor(tonumber(env_worker_processes))
    end

    local exported_vars = file.get_exported_vars()
    if exported_vars then
        if not sys_conf["envs"] then
            sys_conf["envs"]= {}
        end
        for _, cfg_env in ipairs(sys_conf["envs"]) do
            local cfg_name
            local from = str_find(cfg_env, "=", 1, true)
            if from then
                cfg_name = str_sub(cfg_env, 1, from - 1)
            else
                cfg_name = cfg_env
            end

            exported_vars[cfg_name] = false
        end

        for name, value in pairs(exported_vars) do
            if value then
                table_insert(sys_conf["envs"], name .. "=" .. value)
            end
        end
    end

    -- fix up lua path
    sys_conf["extra_lua_path"] = get_lua_path(yaml_conf.apisix.extra_lua_path)
    sys_conf["extra_lua_cpath"] = get_lua_path(yaml_conf.apisix.extra_lua_cpath)

    local conf_render = template.compile(ngx_tpl)
    local ngxconf = conf_render(sys_conf)

    local ok, err = util.write_file(env.apisix_home .. "/conf/nginx.conf",
                                    ngxconf)
    if not ok then
        util.die("failed to update nginx.conf: ", err, "\n")
    end
end


local function init_etcd(env, args)
    etcd.init(env, args)
end


local function start(env, ...)
    -- Because the worker process started by apisix has "nobody" permission,
    -- it cannot access the `/root` directory. Therefore, it is necessary to
    -- prohibit APISIX from running in the /root directory.
    if env.is_root_path then
        util.die("Error: It is forbidden to run APISIX in the /root directory.\n")
    end

    local cmd_logs = "mkdir -p " .. env.apisix_home .. "/logs"
    util.execute_cmd(cmd_logs)

    -- check running
    local pid_path = env.apisix_home .. "/logs/nginx.pid"
    local pid = util.read_file(pid_path)
    pid = tonumber(pid)
    if pid then
        local lsof_cmd = "lsof -p " .. pid
        local hd = popen(lsof_cmd)
        local res = hd:read("*a")
        if not (res and res == "") then
            if not res then
                print("failed to read the result of command: " .. lsof_cmd)
            else
                print("APISIX is running...")
            end

            return
        end

        print("nginx.pid exists but there's no corresponding process with pid ", pid,
              ", the file will be overwritten")
    end

    local parser = argparse()
    parser:argument("_", "Placeholder")
    parser:option("-c --config", "location of customized config.yaml")
    -- TODO: more logs for APISIX cli could be added using this feature
    parser:flag("--verbose", "show init_etcd debug information")
    local args = parser:parse()

    local customized_yaml = args["config"]
    if customized_yaml then
        profile.apisix_home = env.apisix_home .. "/"
        local local_conf_path = profile:yaml_path("config")
        util.execute_cmd("mv " .. local_conf_path .. " " .. local_conf_path .. ".bak")
        util.execute_cmd("ln " .. customized_yaml .. " " .. local_conf_path)
        print("Use customized yaml: ", customized_yaml)
    end

    init(env)
    init_etcd(env, args)

    util.execute_cmd(env.openresty_args)
end


local function stop(env)
    local local_conf_path = profile:yaml_path("config")
    local bak_exist = io_open(local_conf_path .. ".bak")
    if bak_exist then
        util.execute_cmd("rm " .. local_conf_path)
        util.execute_cmd("mv " .. local_conf_path .. ".bak " .. local_conf_path)
    end
    local cmd = env.openresty_args .. [[ -s stop]]
    util.execute_cmd(cmd)
end


local function restart(env)
  stop(env)
  start(env)
end


local function reload(env)
    -- reinit nginx.conf
    init(env)

    local test_cmd = env.openresty_args .. [[ -t -q ]]
    -- When success,
    -- On linux, os.execute returns 0,
    -- On macos, os.execute returns 3 values: true, exit, 0, and we need the first.
    local test_ret = execute((test_cmd))
    if (test_ret == 0 or test_ret == true) then
        local cmd = env.openresty_args .. [[ -s reload]]
        execute(cmd)
        return
    end

    print("test openresty failed")
end


local action = {
    help = help,
    version = version,
    init = init,
    init_etcd = etcd.init,
    start = start,
    stop = stop,
    restart = restart,
    reload = reload,
}


function _M.execute(env, arg)
    local cmd_action = arg[1]
    if not cmd_action then
        return help()
    end

    if not action[cmd_action] then
        stderr:write("invalid argument: ", cmd_action, "\n")
        return help()
    end

    action[cmd_action](env, arg[2])
end


return _M