%%%----------------------------------------------------------------------
%%%
%%% ejabberd, Copyright (C) 2002-2017   ProcessOne
%%%
%%% This program is free software; you can redistribute it and/or
%%% modify it under the terms of the GNU General Public License as
%%% published by the Free Software Foundation; either version 2 of the
%%% License, or (at your option) any later version.
%%%
%%% This program is distributed in the hope that it will be useful,
%%% but WITHOUT ANY WARRANTY; without even the implied warranty of
%%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
%%% General Public License for more details.
%%%
%%% You should have received a copy of the GNU General Public License along
%%% with this program; if not, write to the Free Software Foundation, Inc.,
%%% 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
%%%
%%%----------------------------------------------------------------------

Vars = case file:consult(filename:join([filename:dirname(SCRIPT),"vars.config"])) of
	   {ok, Terms} ->
	       Terms;
	   _Err ->
	       []
       end ++ [{cflags, "-g -O2 -Wall"}, {cppflags, "-g -O2 -Wall"},
	       {ldflags, ""}, {system_deps, false}],
{cflags, CFlags} = lists:keyfind(cflags, 1, Vars),
{cppflags, CPPFlags} = lists:keyfind(cppflags, 1, Vars),
{ldflags, LDFlags} = lists:keyfind(ldflags, 1, Vars),
{system_deps, SystemDeps}  = lists:keyfind(system_deps, 1, Vars),

GetCfg0 = fun(F, Cfg, [Key | Tail], Default) ->
		  Val = case lists:keyfind(Key, 1, Cfg) of
			    {Key, V1} -> V1;
			    false -> Default
			end,
		  case Tail of
		      [] ->
			  Val;
		      _ ->
			  F(F, Val, Tail, Default)
		  end
	  end,
ModCfg0 = fun(F, Cfg, [Key | Tail], Op, Default) ->
		  {OldVal, PartCfg} = case lists:keytake(Key, 1, Cfg) of
					  {value, {_, V1}, V2} -> {V1, V2};
					  false -> {if Tail == [] -> Default; true -> [] end, Cfg}
				      end,
		  case Tail of
		      [] ->
			  [{Key, Op(OldVal)} | PartCfg];
		      _ ->
			  [{Key, F(F, OldVal, Tail, Op, Default)} | PartCfg]
		  end
	  end,

FilterConfig = fun(F, Cfg, [{Path, true, ModFun, Default} | Tail]) ->
		       F(F, ModCfg0(ModCfg0, Cfg, Path, ModFun, Default), Tail);
		  (F, Cfg, [{Path, SourcePath, true, ModFun, Default, SourceDefault} | Tail]) ->
		       SourceVal = GetCfg0(GetCfg0, Cfg, SourcePath, SourceDefault),
		       ModFun2 = fun(V) -> ModFun(V, SourceVal) end,
		       F(F, ModCfg0(ModCfg0, Cfg, Path, ModFun2, Default), Tail);
		  (F, Cfg, [_ | Tail]) ->
		       F(F, Cfg, Tail);
		  (_, Cfg, []) ->
		       Cfg
	       end,

IsRebar3 = case application:get_key(rebar, vsn) of
	       {ok, VSN} ->
		   [VSN1 | _] = string:tokens(VSN, "-"),
		   [Maj, _Min, _Patch] = string:tokens(VSN1, "."),
		   (list_to_integer(Maj) >= 3);
	       undefined ->
		   lists:keymember(mix, 1, application:loaded_applications())
	   end,

SysVer = erlang:system_info(otp_release),

ProcessSingleVar = fun(F, Var, Tail) ->
			   case F(F, [Var], []) of
			       [] -> Tail;
			       [Val] -> [Val | Tail]
			   end
		   end,

ProcessVars = fun(_F, [], Acc) ->
		      lists:reverse(Acc);
		 (F, [{Type, Ver, Value} | Tail], Acc) when
			Type == if_version_above orelse
			Type == if_version_below ->
		      SysVer = erlang:system_info(otp_release),
		      Include = if Type == if_version_above ->
					SysVer > Ver;
				   true ->
					SysVer < Ver
				end,
		      if Include ->
			      F(F, Tail, ProcessSingleVar(F, Value, Acc));
			 true ->
			      F(F, Tail, Acc)
		      end;
		 (F, [{Type, Ver, Value, ElseValue} | Tail], Acc) when
			Type == if_version_above orelse
			Type == if_version_below ->
		      Include = if Type == if_version_above ->
					SysVer > Ver;
				   true ->
					SysVer < Ver
				end,
		      if Include ->
			      F(F, Tail, ProcessSingleVar(F, Value, Acc));
			 true ->
			      F(F, Tail, ProcessSingleVar(F, ElseValue, Acc))
		      end;
		 (F, [{Type, Var, Value} | Tail], Acc) when
			Type == if_var_true orelse
			Type == if_var_false ->
		      Flag = Type == if_var_true,
		      case proplists:get_bool(Var, Vars) of
			  V when V == Flag ->
			      F(F, Tail, ProcessSingleVar(F, Value, Acc));
			  _ ->
			      F(F, Tail, Acc)
		      end;
		 (F, [{Type, Value} | Tail], Acc) when
			Type == if_rebar3 orelse
			Type == if_not_rebar3 ->
		      Flag = Type == if_rebar3,
		      case IsRebar3 == Flag of
			  true ->
			      F(F, Tail, ProcessSingleVar(F, Value, Acc));
			  _ ->
			      F(F, Tail, Acc)
		      end;
		 (F, [{Type, Var, Match, Value} | Tail], Acc) when
			Type == if_var_match orelse
			Type == if_var_no_match ->
		      case proplists:get_value(Var, Vars) of
			  V when V == Match ->
			      F(F, Tail, ProcessSingleVar(F, Value, Acc));
			  _ ->
			      F(F, Tail, Acc)
		      end;
		 (F, [{if_have_fun, MFA, Value} | Tail], Acc) ->
		      {Mod, Fun, Arity} = MFA,
		      code:ensure_loaded(Mod),
		      case erlang:function_exported(Mod, Fun, Arity) of
			  true ->
			      F(F, Tail, ProcessSingleVar(F, Value, Acc));
			  false ->
			      F(F, Tail, Acc)
		      end;
		 (F, [Other1 | Tail1], Acc) ->
		      F(F, Tail1, [F(F, Other1, []) | Acc]);
		 (F, Val, Acc) when is_tuple(Val) ->
		      list_to_tuple(F(F, tuple_to_list(Val), Acc));
		 (_F, Other2, _Acc) ->
		      Other2
	      end,

MaybeApply = fun(Val) when is_function(Val) ->
		     Val();
		(Val) ->
		     Val
	     end,
MaybeApply2 = fun(Val, Arg) when is_function(Val) ->
		      Val(Arg);
		 (Val, _) ->
		      Val
	      end,

AppendStr = fun(Append) ->
		    fun("") ->
			    lists:flatten(MaybeApply(Append));
		       (Val) ->
			    lists:flatten([Val, " ", MaybeApply(Append)])
		    end
	    end,
AppendList = fun(Append) ->
		     fun(Val) ->
			     Val ++ MaybeApply(Append)
		     end
	     end,
AppendStr2 = fun(Append) ->
		     fun("", Arg) ->
			     lists:flatten(MaybeApply2(Append, Arg));
			(Val, Arg) ->
			     lists:flatten([Val, " ", MaybeApply2(Append, Arg)])
		     end
	     end,
AppendList2 = fun(Append) ->
		      fun(Val, Arg) ->
			      Val ++ MaybeApply2(Append, Arg)
		      end
	      end,

Rebar3DepsFilter =
fun(DepsList) ->
	lists:map(fun({DepName, _, {git, _, {tag, Version}}}) ->
			  {DepName, Version};
		     (Dep) ->
			  Dep
		  end, DepsList)
end,

GlobalDepsFilter =
fun(Deps) ->
	DepNames = lists:map(fun({DepName, _, _}) -> DepName;
				({DepName, _}) -> DepName
			     end, Deps),
	lists:filtermap(fun(Dep) ->
				case code:lib_dir(Dep) of
				    {error, _} ->
					{true, "Unable to locate dep '" ++ atom_to_list(Dep) ++ "' in system deps."};
				    _ ->
					false
				end
			end, DepNames)
end,

{ok, Cwd} = file:get_cwd(),
TestConfigFile = filename:join([Cwd, "test", "config.ctc"]),
TestConfig = case file:read_file_info(TestConfigFile) of
		 {ok, _} ->
		     [" -userconfig ct_config_plain ", TestConfigFile, " "];
		 _ ->
		     ""
	     end,

ResolveDepPath = case {SystemDeps, IsRebar3} of
		     {true, _} ->
			 fun("deps/" ++ Rest) ->
				 Slash = string:str(Rest, "/"),
				 case code:lib_dir(string:sub_string(Rest, 1, Slash -1)) of
				     {error, _} -> Rest;
				     V -> V ++ string:sub_string(Rest, Slash)
				 end;
			    (Path) ->
				 Path
			 end;
		     {_, true} ->
			 fun("deps/" ++ Rest) ->
				 Slash = string:str(Rest, "/"),
				 "_build/default/lib/" ++
				     string:sub_string(Rest, 1, Slash - 1) ++
				     string:sub_string(Rest, Slash);
			    (Path) ->
				 Path
			 end;
		     _ ->
			 fun(P) ->
				 P
			 end
		 end,

CtParams = fun(CompileOpts) ->
		   ["-ct_hooks cth_surefire ",
		    lists:map(fun({i, IncPath}) ->
				      [" -include ", filename:join([Cwd, ResolveDepPath(IncPath)])]
			      end, CompileOpts),
		    TestConfig]
	   end,

GenDepConfigureLine =
fun(DepPath, Flags) ->
	["sh -c 'if test ! -f config.status -o ",
	 "../../config.status -nt config.status; ",
	 "then (",
	 "CFLAGS=\"", CFlags,"\" ",
	 "CPPFLAGS=\"", CPPFlags, "\" "
	 "LDFLAGS=\"", LDFlags, "\"",
	 " ./configure ", string:join(Flags, " "),
	 "); fi'"]
end,

GenDepsConfigure =
fun(Hooks) ->
	lists:map(fun({Pkg, Flags}) ->
			  DepPath = ResolveDepPath("deps/" ++ Pkg ++ "/"),
			  {add, list_to_atom(Pkg), [{pre_hooks, {'compile',
			   lists:flatten(GenDepConfigureLine(DepPath, Flags))}}]}
		  end, Hooks)
end,

ProcessErlOpt = fun(Vals) ->
			lists:map(
			  fun({i, Path}) ->
				  {i, ResolveDepPath(Path)};
			     (ErlOpt) ->
				  ErlOpt
			  end, Vals)
		end,

ProcssXrefExclusions = fun(Items) ->
			       [{lists:flatten(["(XC - UC) || (XU - X - B ",
					       [[" - ", V] || V <- Items], ")"]),
				[]}]
		       end,

ProcessFloatingDeps =
fun(Deps, FDeps) ->
	lists:map(fun({DepName, _Ver, {git, Repo, _Commit}} = Dep) ->
			  case lists:member(DepName, FDeps) of
			      true ->
				  {DepName, ".*", {git, Repo}};
			      _ ->
				  Dep
			  end;
		     (Dep2) ->
			  Dep2
		  end, Deps)
end,

TravisPostHooks =
fun(true) ->
	[{eunit, "echo '\n%%! -pa .eunit/ deps/coveralls/ebin\n" ++
	      "main(_)->{ok,F}=file:open(\"erlang.json\",[write])," ++
	      "io:fwrite(F,\"~s\",[coveralls:convert_file(" ++
	      "\".eunit/cover.coverdata\", \"" ++
	      os:getenv("TRAVIS_JOB_ID") ++
	      "\", \"travis-ci\",\"\")]).' > getcover.erl"},
	 {eunit, "escript ./getcover.erl"}];
   (_) ->
	[]
end,

Rules = [
	 {[provider_hooks], IsRebar3,
	  AppendList([{pre, [
			     {compile, {asn, compile}},
			     {clean, {asn, clean}}
			    ]}]), []},
	 {[deps], os:getenv("TRAVIS") == "true",
	  AppendList([{coveralls, ".*", {git, "https://github.com/markusn/coveralls-erl.git", "master"}}]), []},
	 {[post_hooks], [cover_enabled], os:getenv("TRAVIS") == "true",
	  AppendList2(TravisPostHooks), [], false},
	 {[overrides], [post_hook_configure], SystemDeps == false,
	  AppendList2(GenDepsConfigure), [], []},
	 {[ct_extra_params], [eunit_compile_opts], true,
	  AppendStr2(CtParams), "", []},
	 {[erl_opts], true,
	  ProcessErlOpt, []},
	 {[xref_queries], [xref_exclusions], true,
	  AppendList2(ProcssXrefExclusions), [], []},
	 {[deps], [floating_deps], true,
	  ProcessFloatingDeps, [], []},
	 {[deps], IsRebar3,
	  Rebar3DepsFilter, []},
	 {[deps], SystemDeps /= false,
	  GlobalDepsFilter, []}
	],

Config = [{plugin_dir, filename:join([filename:dirname(SCRIPT),"plugins"])}]++
FilterConfig(FilterConfig, ProcessVars(ProcessVars, CONFIG, []), Rules),

%io:format("ejabberd configuration:~n  ~p~n", [Config]),

Config.

%% Local Variables:
%% mode: erlang
%% End:
%% vim: set filetype=erlang tabstop=8: