%---------------------------------------------------------------------------%
% vim: ft=mercury ts=4 sw=4 et
%---------------------------------------------------------------------------%
% Copyright (C) 1995-1997, 1999, 2002, 2004-2012 The University of Melbourne.
% Copyright (C) 2013, 2015-2023 The Mercury team.
% This file may only be copied under the terms of the GNU General
% Public License - see the file COPYING in the Mercury distribution.
%---------------------------------------------------------------------------%
%
% Mercury profiler
% Main author: petdr.
%
% Processes the Prof.* and the *.prof files to produce an output very similar
% to `gprof'
%
% Based on the profiling scheme described in the paper: Graham, Kessler and
% McKusick "Gprof: a call graph execution profiler", Proceedings of the 1982
% SIGPLAN Symposium on Compiler Construction, pages 120-126.
%
%---------------------------------------------------------------------------%
%---------------------------------------------------------------------------%

:- module mercury_profile.
:- interface.

:- import_module io.

:- pred main(io::di, io::uo) is det.

%---------------------------------------------------------------------------%
%---------------------------------------------------------------------------%

:- implementation.

:- import_module call_graph.
:- import_module generate_output.
:- import_module globals.
:- import_module options.
:- import_module output.
:- import_module process_file.
:- import_module propagate.
:- import_module snapshots.

:- import_module bool.
:- import_module getopt.
:- import_module library.
:- import_module list.
:- import_module string.

%---------------------------------------------------------------------------%

main(!IO) :-
    io.command_line_arguments(Args0, !IO),
    OptionOps = option_ops_multi(short_option, long_option, option_default,
        special_handler),
    getopt.process_options(OptionOps, Args0, Args, GetoptResult),
    (
        GetoptResult = error(Error),
        ErrorMessage = option_error_to_string(Error),
        usage_error(ErrorMessage, !IO)
    ;
        GetoptResult = ok(OptionTable0),
        globals.io_init(OptionTable0, !IO),
        postprocess_options(Args, !IO),
        main_2(Args, !IO)
    ).

:- pred postprocess_options(list(string)::in,
    io::di, io::uo) is det.

postprocess_options(Args, !IO) :-
    % --very-verbose implies --verbose
    globals.io_lookup_bool_option(very_verbose, VeryVerbose, !IO),
    (
        VeryVerbose = yes,
        globals.io_set_option(verbose, bool(yes), !IO)
    ;
        VeryVerbose = no
    ),

    % Any empty list of arguments implies that we must build the call
    % graph from the dynamic information.
    (
        Args = [],
        globals.io_set_option(dynamic_cg, bool(yes), !IO)
    ;
        Args = [_ | _]
    ).

%---------------------------------------------------------------------------%

:- pred display_version(io.text_output_stream::in, io::di, io::uo) is det.

display_version(OutputStream, !IO) :-
    Version = library.mercury_version,
    io.format(OutputStream, "Mercury profiler, version %s", [s(Version)],
        !IO),
    Package = library.package_version,
    ( if Package = "" then
        io.nl(OutputStream, !IO)
    else
        io.format(OutputStream, " (%s)\n", [s(Package)], !IO)
    ),
    write_copyright_notice(OutputStream, !IO).

    % Display error message and then short usage message.
    %
:- pred usage_error(string::in, io::di, io::uo) is det.

usage_error(ErrorMessage, !IO) :-
    io.progname_base("mercury_profile", ProgName, !IO),
    io.stderr_stream(StdErr, !IO),
    io.format(StdErr, "%s: %s\n", [s(ProgName), s(ErrorMessage)], !IO),
    io.set_exit_status(1, !IO),
    short_usage(StdErr, !IO).

    % Display short_usage message.
    % XXX the only place we call short_usage is in usage_error above.
    % Also: why does the default name of the executable differ betweeen
    % the two?
:- pred short_usage(io.text_output_stream::in, io::di, io::uo) is det.

short_usage(OutputStream, !IO) :-
    io.progname_base("mprof", ProgName, !IO),
    io.format(OutputStream, "Usage: %s[<options>] [<files>]\n",
        [s(ProgName)], !IO),
    io.format(OutputStream, "Use `%s --help' for more information.\n",
        [s(ProgName)], !IO).

:- pred long_usage(io.text_output_stream::in, io::di, io::uo) is det.

long_usage(OutputStream, !IO) :-
    io.progname_base("mprof", ProgName, !IO),
    io.write_string(OutputStream, "Name: mprof - Mercury profiler\n", !IO),
    write_copyright_notice(OutputStream, !IO),
    io.write_strings(OutputStream, [
        "Usage: ", ProgName, " [<options>] [<files>]\n",
        "\n",
        "Description:\n"
    ], !IO),
    io.write_prefixed_lines(OutputStream, "\t", [
        "`mprof' produces execution profiles for Mercury programs.",
        "It outputs a flat profile and optionally also a hierarchical",
        "(call graph based) profile based on data collected during program",
        "execution."
    ], !IO),
    io.write_string(OutputStream, "\nArguments:\n", !IO),
    io.write_prefixed_lines(OutputStream, "\t", [
        "If no <files> are specified, then the `--use-dynamic' option",
        "is implied: the call graph will be built dynamically.",
        "Otherwise, the <files> specified should be the `.prof' file",
        "for every module in the program. The `.prof' files, which are",
        "generated automatically by the Mercury compiler, contain the",
        "program's static call graph."
    ], !IO),
    io.write_string(OutputStream, "\nOptions:\n", !IO),
    options_help(OutputStream, !IO).

:- pred write_copyright_notice(io.text_output_stream::in, io::di, io::uo)
    is det.

write_copyright_notice(OutputStream, !IO) :-
    io.write_strings(OutputStream, [
        "Copyright (C) 1995-2012 The University of Melbourne\n",
        "Copyright (C) 2013-2023 The Mercury team\n"
    ], !IO).

%---------------------------------------------------------------------------%

:- pred main_2(list(string)::in, io::di, io::uo) is det.

main_2(Args, !IO) :-
    globals.io_get_globals(Globals, !IO),
    io.stdout_stream(StdOut, !IO),
    ( if globals.lookup_bool_option(Globals, help, yes) then
        long_usage(StdOut, !IO)
    else if globals.lookup_bool_option(Globals, version, yes) then
        display_version(StdOut, !IO)
    else
        globals.lookup_bool_option(Globals, snapshots, Snapshots),
        (
            Snapshots = yes,
            show_snapshots(StdOut, !IO)
        ;
            Snapshots = no,
            main_3(Args, !IO)
        )
    ).

:- pred main_3(list(string)::in, io::di, io::uo) is det.

main_3(Args, !IO) :-
    io.stderr_stream(StdErr, !IO),
    % ZZZ io.set_output_stream(StdErr, StdOut, !IO),
    globals.io_lookup_bool_option(verbose, Verbose, !IO),

    ProgressStream = StdErr,
    maybe_write_string(ProgressStream, Verbose,
        "% Processing input files...", !IO),
    process_profiling_data_files(ProgressStream, StdErr,
        Prof0, CallGraph0, !IO),
    maybe_write_string(ProgressStream, Verbose,
        " done\n", !IO),

    globals.io_lookup_bool_option(call_graph, CallGraphOpt, !IO),
    (
        CallGraphOpt = yes,
        maybe_write_string(ProgressStream, Verbose,
            "% Building call graph...", !IO),
        build_call_graph(ProgressStream, Args, CallGraph0, CallGraph, !IO),
        maybe_write_string(ProgressStream, Verbose,
            " done\n", !IO),

        maybe_write_string(ProgressStream, Verbose,
            "% Propagating counts...", !IO),
        propagate_counts(CallGraph, Prof0, Prof, !IO),
        maybe_write_string(ProgressStream, Verbose,
            " done\n", !IO)
    ;
        CallGraphOpt = no,
        Prof = Prof0
    ),

    maybe_write_string(ProgressStream, Verbose,
        "% Generating output...", !IO),
    generate_prof_output(ProgressStream, Prof, IndexMap, ProfilerOutput, !IO),
    maybe_write_string(ProgressStream, Verbose,
        " done\n", !IO),

    io.stdout_stream(StdOut, !IO),
    output_profile(StdOut, ProfilerOutput, IndexMap, !IO).

%---------------------------------------------------------------------------%
:- end_module mercury_profile.
%---------------------------------------------------------------------------%
