# Copyright (c) 2014, Loïc Hoguin <essen@ninenines.eu>
# This file is part of erlang.mk and subject to the terms of the ISC License.

.PHONY: bootstrap bootstrap-lib bootstrap-rel new list-templates

# Core targets.

help::
	@printf "%s\n" "" \
		"Bootstrap targets:" \
		"  bootstrap          Generate a skeleton of an OTP application" \
		"  bootstrap-lib      Generate a skeleton of an OTP library" \
		"  bootstrap-rel      Generate the files needed to build a release" \
		"  new t=TPL n=NAME   Generate a module NAME based on the template TPL" \
		"  list-templates     List available templates"

# Bootstrap templates.

bs_appsrc = "{application, $(PROJECT), [" \
	"	{description, \"\"}," \
	"	{vsn, \"0.1.0\"}," \
	"	{id, \"git\"}," \
	"	{modules, []}," \
	"	{registered, []}," \
	"	{applications, [" \
	"		kernel," \
	"		stdlib" \
	"	]}," \
	"	{mod, {$(PROJECT)_app, []}}," \
	"	{env, []}" \
	"]}."
bs_appsrc_lib = "{application, $(PROJECT), [" \
	"	{description, \"\"}," \
	"	{vsn, \"0.1.0\"}," \
	"	{id, \"git\"}," \
	"	{modules, []}," \
	"	{registered, []}," \
	"	{applications, [" \
	"		kernel," \
	"		stdlib" \
	"	]}" \
	"]}."
bs_Makefile = "PROJECT = $(PROJECT)" \
	"include erlang.mk"
bs_app = "-module($(PROJECT)_app)." \
	"-behaviour(application)." \
	"" \
	"-export([start/2])." \
	"-export([stop/1])." \
	"" \
	"start(_Type, _Args) ->" \
	"	$(PROJECT)_sup:start_link()." \
	"" \
	"stop(_State) ->" \
	"	ok."
bs_relx_config = "{release, {$(PROJECT)_release, \"1\"}, [$(PROJECT)]}." \
	"{extended_start_script, true}." \
	"{sys_config, \"rel/sys.config\"}." \
	"{vm_args, \"rel/vm.args\"}."
bs_sys_config = "[" \
	"]."
bs_vm_args = "-name $(PROJECT)@127.0.0.1" \
	"-setcookie $(PROJECT)" \
	"-heart"
# Normal templates.
tpl_supervisor = "-module($(n))." \
	"-behaviour(supervisor)." \
	"" \
	"-export([start_link/0])." \
	"-export([init/1])." \
	"" \
	"start_link() ->" \
	"	supervisor:start_link({local, ?MODULE}, ?MODULE, [])." \
	"" \
	"init([]) ->" \
	"	Procs = []," \
	"	{ok, {{one_for_one, 1, 5}, Procs}}."
tpl_gen_server = "-module($(n))." \
	"-behaviour(gen_server)." \
	"" \
	"%% API." \
	"-export([start_link/0])." \
	"" \
	"%% gen_server." \
	"-export([init/1])." \
	"-export([handle_call/3])." \
	"-export([handle_cast/2])." \
	"-export([handle_info/2])." \
	"-export([terminate/2])." \
	"-export([code_change/3])." \
	"" \
	"-record(state, {" \
	"})." \
	"" \
	"%% API." \
	"" \
	"-spec start_link() -> {ok, pid()}." \
	"start_link() ->" \
	"	gen_server:start_link(?MODULE, [], [])." \
	"" \
	"%% gen_server." \
	"" \
	"init([]) ->" \
	"	{ok, \#state{}}." \
	"" \
	"handle_call(_Request, _From, State) ->" \
	"	{reply, ignored, State}." \
	"" \
	"handle_cast(_Msg, State) ->" \
	"	{noreply, State}." \
	"" \
	"handle_info(_Info, State) ->" \
	"	{noreply, State}." \
	"" \
	"terminate(_Reason, _State) ->" \
	"	ok." \
	"" \
	"code_change(_OldVsn, State, _Extra) ->" \
	"	{ok, State}."
tpl_cowboy_http = "-module($(n))." \
	"-behaviour(cowboy_http_handler)." \
	"" \
	"-export([init/3])." \
	"-export([handle/2])." \
	"-export([terminate/3])." \
	"" \
	"-record(state, {" \
	"})." \
	"" \
	"init(_, Req, _Opts) ->" \
	"	{ok, Req, \#state{}}." \
	"" \
	"handle(Req, State=\#state{}) ->" \
	"	{ok, Req2} = cowboy_req:reply(200, Req)," \
	"	{ok, Req2, State}." \
	"" \
	"terminate(_Reason, _Req, _State) ->" \
	"	ok."
tpl_cowboy_loop = "-module($(n))." \
	"-behaviour(cowboy_loop_handler)." \
	"" \
	"-export([init/3])." \
	"-export([info/3])." \
	"-export([terminate/3])." \
	"" \
	"-record(state, {" \
	"})." \
	"" \
	"init(_, Req, _Opts) ->" \
	"	{loop, Req, \#state{}, 5000, hibernate}." \
	"" \
	"info(_Info, Req, State) ->" \
	"	{loop, Req, State, hibernate}." \
	"" \
	"terminate(_Reason, _Req, _State) ->" \
	"	ok."
tpl_cowboy_rest = "-module($(n))." \
	"" \
	"-export([init/3])." \
	"-export([content_types_provided/2])." \
	"-export([get_html/2])." \
	"" \
	"init(_, _Req, _Opts) ->" \
	"	{upgrade, protocol, cowboy_rest}." \
	"" \
	"content_types_provided(Req, State) ->" \
	"	{[{{<<\"text\">>, <<\"html\">>, '*'}, get_html}], Req, State}." \
	"" \
	"get_html(Req, State) ->" \
	"	{<<\"<html><body>This is REST!</body></html>\">>, Req, State}."
tpl_cowboy_ws = "-module($(n))." \
	"-behaviour(cowboy_websocket_handler)." \
	"" \
	"-export([init/3])." \
	"-export([websocket_init/3])." \
	"-export([websocket_handle/3])." \
	"-export([websocket_info/3])." \
	"-export([websocket_terminate/3])." \
	"" \
	"-record(state, {" \
	"})." \
	"" \
	"init(_, _, _) ->" \
	"	{upgrade, protocol, cowboy_websocket}." \
	"" \
	"websocket_init(_, Req, _Opts) ->" \
	"	Req2 = cowboy_req:compact(Req)," \
	"	{ok, Req2, \#state{}}." \
	"" \
	"websocket_handle({text, Data}, Req, State) ->" \
	"	{reply, {text, Data}, Req, State};" \
	"websocket_handle({binary, Data}, Req, State) ->" \
	"	{reply, {binary, Data}, Req, State};" \
	"websocket_handle(_Frame, Req, State) ->" \
	"	{ok, Req, State}." \
	"" \
	"websocket_info(_Info, Req, State) ->" \
	"	{ok, Req, State}." \
	"" \
	"websocket_terminate(_Reason, _Req, _State) ->" \
	"	ok."
tpl_ranch_protocol = "-module($(n))." \
	"-behaviour(ranch_protocol)." \
	"" \
	"-export([start_link/4])." \
	"-export([init/4])." \
	"" \
	"-type opts() :: []." \
	"-export_type([opts/0])." \
	"" \
	"-record(state, {" \
	"	socket :: inet:socket()," \
	"	transport :: module()" \
	"})." \
	"" \
	"start_link(Ref, Socket, Transport, Opts) ->" \
	"	Pid = spawn_link(?MODULE, init, [Ref, Socket, Transport, Opts])," \
	"	{ok, Pid}." \
	"" \
	"-spec init(ranch:ref(), inet:socket(), module(), opts()) -> ok." \
	"init(Ref, Socket, Transport, _Opts) ->" \
	"	ok = ranch:accept_ack(Ref)," \
	"	loop(\#state{socket=Socket, transport=Transport})." \
	"" \
	"loop(State) ->" \
	"	loop(State)."

# Plugin-specific targets.

bootstrap:
ifneq ($(wildcard src/),)
	$(error Error: src/ directory already exists)
endif
	@printf "%s\n" $(bs_Makefile) > Makefile
	@mkdir src/
	@printf "%s\n" $(bs_appsrc) > src/$(PROJECT).app.src
	@printf "%s\n" $(bs_app) > src/$(PROJECT)_app.erl
	$(eval n := $(PROJECT)_sup)
	@printf "%s\n" $(tpl_supervisor) > src/$(PROJECT)_sup.erl

bootstrap-lib:
ifneq ($(wildcard src/),)
	$(error Error: src/ directory already exists)
endif
	@printf "%s\n" $(bs_Makefile) > Makefile
	@mkdir src/
	@printf "%s\n" $(bs_appsrc_lib) > src/$(PROJECT).app.src

bootstrap-rel:
ifneq ($(wildcard relx.config),)
	$(error Error: relx.config already exists)
endif
ifneq ($(wildcard rel/),)
	$(error Error: rel/ directory already exists)
endif
	@printf "%s\n" $(bs_relx_config) > relx.config
	@mkdir rel/
	@printf "%s\n" $(bs_sys_config) > rel/sys.config
	@printf "%s\n" $(bs_vm_args) > rel/vm.args

new:
ifeq ($(wildcard src/),)
	$(error Error: src/ directory does not exist)
endif
ifndef t
	$(error Usage: make new t=TEMPLATE n=NAME)
endif
ifndef tpl_$(t)
	$(error Unknown template)
endif
ifndef n
	$(error Usage: make new t=TEMPLATE n=NAME)
endif
	@printf "%s\n" $(tpl_$(t)) > src/$(n).erl

list-templates:
	@echo Available templates: $(sort $(patsubst tpl_%,%,$(filter tpl_%,$(.VARIABLES))))