%%% @doc
%%% GSC CLI: explorer/harness for sfc iteration
%%% @end

-module(gsc_cli).
-vsn("0.1.0").
-author("Peter Harpending <peterharpending@qpq.swiss>").
-copyright("Peter Harpending <peterharpending@qpq.swiss>").
-license("GPL-3.0-only").

-export([start/1]).

-include("$gsc_include/gsc.hrl").
-include("ansi.hrl").

do_help() ->
    io:format("~ts", [help_screen()]).

help_screen() ->
    ["you can't help people who refuse to help themsleves\n"].

-spec start(ArgV) -> ok
    when ArgV :: [string()].

start([]) ->
    do_eshell(),
    ok;
start(["shell"]) ->
    do_eshell(),
    ok;
start(["eshell"]) ->
    do_eshell(),
    ok;
start(ArgV) ->
    %io:format("ArgV: ~p~n", [ArgV]),
    do(ArgV),
    zx:silent_stop().

do(["list"]) ->
    do_tlist();
do(["list", "tests"]) ->
    do_tlist();
do(["run", "tests"]) ->
    io:format("TestModules = ~p~n", [known_modules_with_prefix("ts")]),
    do_runall_tests();
do(["tokenizers_agree", Foo]) ->
    io:format("~p~n", [tokenizers_agree(Foo)]);
% slowly phasing out shitty names like lctokens
% tokens = native sfc token representation
do(["tokens", Foo]) -> do_tokens(Foo);
do(["color_tokens", Foo]) -> do_color_tokens(Foo);
do(["ctokens", Foo]) -> do_color_tokens(Foo);
do(["colour_tokens" | _]) -> do_doi();
% so_tokens = so_scan tokens
do(["so", "tokens", Foo]) -> do_so_tokens(Foo);
do(["so_tokens", Foo]) -> do_so_tokens(Foo);
% gso_tokens = our mockery
do(["gso", "tokens", Foo]) -> do_gso_tokens(Foo);
do(["gso_tokens", Foo]) -> do_gso_tokens(Foo);
% print source file to screen with token boundaries highlighted
% script utility
do(["rmm", Foo]) ->
    do_rmm(Foo);
do(Args) ->
    io:format("bad args: ~p~n", [Args]),
    do_help().

do_doi() ->
    FP = zx:get_home() ++ "/priv/doi.txt",
    Cmd = "less " ++ FP,
    io:format("~s~n", [Cmd]).


do_runall_tests() ->
    lists:foreach(fun run_mod_main/1, test_mods()).

test_mods() ->
    known_modules_with_prefix("gt_").

known_modules_with_prefix(Pfx) ->
    ModsZipBeamsZipLoaded = code:all_available(),
    kmp(Pfx, ModsZipBeamsZipLoaded, []).

kmp(_Pfx, [], Acc) ->
    lists:sort(Acc);
kmp(Pfx, [{ModStr, _BeamPath, _Loaded} | Rest], Acc) ->
    case lists:prefix(Pfx, ModStr) of
        false -> kmp(Pfx, Rest, Acc);
        true  -> kmp(Pfx, Rest, [list_to_atom(ModStr) | Acc])
    end.

run_mod_main(Mod) ->
    io:format("========================================\n"
              "~p:main()\n"
              "========================================\n",
              [Mod]),
    try
        Mod:main()
    catch
        Err:ErrType:Trace ->
            io:format("~p: ~p~n", [Err, ErrType]),
            io:format("Trace:~n~p~n", [Trace])
    end.

do_tlist() ->
    lists:foreach(
        fun(ModName) ->
            io:format("~s~n", [ModName])
        end,
        test_mods()
    ).


-spec do_eshell() -> ok.
% @doc start an erlang shell

do_eshell() ->
    io:format("Welcome to the GSC shell!~n", []),
    case shell:start_interactive() of
        ok -> ok;
        {error, already_started} -> ok;
        {error, Reason} -> error(Reason)
    end.

tokenizers_agree(File) ->
    so_tokens(File) =:= tokens(File).


do_tokens(FilePath) ->
    [io:format("~p~n", [Tk]) || Tk <- tokens(FilePath)].

do_so_tokens(FilePath) ->
    [io:format("~p~n", [Tk]) || Tk <- so_tokens(FilePath)].

do_gso_tokens(FilePath) ->
    [io:format("~p~n", [Tk]) || Tk <- gso_tokens(FilePath)].


% rmm = run module:main() with our context loaded
% useful for prototyping
do_rmm(FilePath) ->
    case compile:file(FilePath) of
        {ok, Mod} -> Mod:main();
        Error     -> error(Error)
    end.


so_tokens(FilePath) ->
    {ok, FileBytes} = file:read_file(FilePath),
    FileStr = unicode:characters_to_nfc_list(FileBytes),
    {ok, Tokens} = so_scan:scan(FileStr),
    Tokens.

gso_tokens(FilePath) ->
    {ok, FileBytes} = file:read_file(FilePath),
    FileStr = unicode:characters_to_nfc_list(FileBytes),
    {ok, Tokens} = gso_scan:scan(FileStr),
    Tokens.


tokens(FilePath) ->
    {ok, Tokens} = gsc:tokens_from_file(FilePath),
    Tokens.


do_color_tokens(File) ->
    case gsc:tokens_from_file(File) of
        {ok, Tokens} ->
            ColorizedSrcStr = colorize_tokens(chunk_color_wheel(), Tokens, ""),
            Full = [?ANSI_INVERT, ColorizedSrcStr, ?ANSI_UNINVERT],
            io:format("~s", [Full]);
        Error ->
            io:format("~p~n", [Error])
    end.

chunk_color_wheel() ->
    %[yellow, blue].
    [red, green, yellow, blue, magenta, cyan].



colorize_tokens(Wheel, [T | Ts], Acc) ->
    {Color, NewWheel} = rotate(Wheel),
    NewAcc = [Acc, colorize_token_str(Color, T)],
    colorize_tokens(NewWheel, Ts, NewAcc);
colorize_tokens(_, [], Acc) ->
    Acc.

rotate([A | Rest]) ->
    {A, Rest ++ [A]}.

colorize_token_str(Color, #tk{str = Str}) ->
    {Pfx, Sfx} = color_fixes(Color),
    [Pfx, Str, Sfx].

color_fixes(red)     -> {?ANSI_FG_RED,     ?ANSI_FG_RESET};
color_fixes(green)   -> {?ANSI_FG_GREEN,   ?ANSI_FG_RESET};
color_fixes(yellow)  -> {?ANSI_FG_YELLOW,  ?ANSI_FG_RESET};
color_fixes(blue)    -> {?ANSI_FG_BLUE,    ?ANSI_FG_RESET};
color_fixes(magenta) -> {?ANSI_FG_MAGENTA, ?ANSI_FG_RESET};
color_fixes(cyan)    -> {?ANSI_FG_CYAN,    ?ANSI_FG_RESET}.