#!/usr/bin/perl -w

# -*- Mode: perl; indent-tabs-mode: nil; c-basic-offset: 2  -*-

#

#  Copyright (C) 2000, 2001 Eazel, Inc.

#  Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007 Apple Inc.

#

#  prepare-ChangeLog 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.

#

#  prepare-ChangeLog 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., 675 Mass Ave, Cambridge, MA 02139, USA.

#

# Perl script to create a ChangeLog entry with names of files

# and functions from a diff.

#

# Darin Adler <darin@bentspoon.com>, started 20 April 2000

# Java support added by Maciej Stachowiak <mjs@eazel.com>

# Objective-C, C++ and Objective-C++ support added by Maciej Stachowiak <mjs@apple.com>

# Git support added by Adam Roben <aroben@apple.com>

#

# TODO:

#   List functions that have been removed too.

#   Decide what a good logical order is for the changed files

#     other than a normal text "sort" (top level first?)

#     (group directories?) (.h before .c?)

#   Handle yacc source files too (other languages?).

#   Help merge when there are ChangeLog conflicts or if there's

#     already a partly written ChangeLog entry.

#   Add command line option to put the ChangeLog into a separate

#     file or just spew it out stdout.

#   Add SVN version numbers for commit (can't do that until

#     the changes are checked in, though).

#   Work around diff stupidity where deleting a function that starts

#     with a comment makes diff think that the following function

#     has been changed (if the following function starts with a comment

#     with the same first line, such as /**)

#   Work around diff stupidity where deleting an entire function and

#     the blank lines before it makes diff think you've changed the

#     previous function.

use strict;

use warnings;

use File::Basename;

use File::Spec;

use FindBin;

use Getopt::Long;

use lib $FindBin::Bin;

use POSIX qw(strftime);

use VCSUtils;

sub changeLogDate($);

sub firstDirectoryOrCwd();

sub diffFromToString();

sub diffCommand(@);

sub statusCommand(@);

sub createPatchCommand($);

sub diffHeaderFormat();

sub findOriginalFileFromSvn($);

sub generateFileList(\@\@\%);

sub gitConfig($);

sub isModifiedStatus($);

sub isAddedStatus($);

sub isConflictStatus($);

sub statusDescription($$);

sub extractLineRange($);

sub canonicalizePath($);

sub testListForChangeLog(@);

sub get_function_line_ranges($$);

sub get_function_line_ranges_for_c($$);

sub get_function_line_ranges_for_java($$);

sub method_decl_to_selector($);

sub processPaths(\@);

sub reviewerAndDescriptionForGitCommit($);

# Project time zone for Cupertino, CA, US

my $changeLogTimeZone = "PST8PDT";

my $gitCommit = 0;

my $gitReviewer = "";

my $openChangeLogs = 0;

my $showHelp = 0;

my $spewDiff = $ENV{"PREPARE_CHANGELOG_DIFF"};

my $updateChangeLogs = 1;

my $parseOptionsResult =

    GetOptions("diff|d!" => \$spewDiff,

               "git-commit:s" => \$gitCommit,

               "git-reviewer:s" => \$gitReviewer,

               "help|h!" => \$showHelp,

               "open|o!" => \$openChangeLogs,

               "update!" => \$updateChangeLogs);

if (!$parseOptionsResult || $showHelp) {

    print STDERR basename($0) . " [-d|--diff] [-h|--help] [-o|--open] [--git-commit=<committish>] [--git-reviewer=<name>] [svndir1 [svndir2 ...]]\n";

    print STDERR "  -d|--diff      Spew diff to stdout when running\n";

    print STDERR "  --git-commit   Populate the ChangeLogs from the specified git commit\n";

    print STDERR "  --git-reviewer When populating the ChangeLogs from a git commit claim that the spcified name reviewed the change.\n";

    print STDERR "                 This option is useful when the git commit lacks a Signed-Off-By: line\n";

    print STDERR "  -h|--help      Show this help message\n";

    print STDERR "  -o|--open      Open ChangeLogs in an editor when done\n";

    print STDERR "  --[no-]update  Update ChangeLogs from svn before adding entry (default: update)\n";

    exit 1;

}

my %paths = processPaths(@ARGV);

my $isGit = isGitDirectory(firstDirectoryOrCwd());

my $isSVN = isSVNDirectory(firstDirectoryOrCwd());

$isSVN || $isGit || die "Couldn't determine your version control system.";

# Find the list of modified files

my @changed_files;

my $changed_files_string;

my %changed_line_ranges;

my %function_lists;

my @conflict_files;

my $SVN = "svn";

my $GIT = "git";

my %supportedTestExtensions = map { $_ => 1 } qw(html shtml svg xml xhtml pl php);

my @addedRegressionTests = ();

my $didChangeRegressionTests = 0;

generateFileList(@changed_files, @conflict_files, %function_lists);

if (!@changed_files && !@conflict_files || !%function_lists) {

    print STDERR "  No changes found.\n";

    exit 1;

}

if (@conflict_files) {

    print STDERR "  The following files have conflicts. Run prepare-ChangeLog again after fixing the conflicts:\n";

    print STDERR join("\n", @conflict_files), "\n";

    exit 1;

}

if (@changed_files) {

    $changed_files_string = "'" . join ("' '", @changed_files) . "'";

    # For each file, build a list of modified lines.

    # Use line numbers from the "after" side of each diff.

    print STDERR "  Reviewing diff to determine which lines changed.\n";

    my $file;

    open DIFF, "-|", diffCommand(@changed_files) or die "The diff failed: $!.\n";

    while (<DIFF>) {

        $file = makeFilePathRelative($1) if $_ =~ diffHeaderFormat();

        if (defined $file) {

            my ($start, $end) = extractLineRange($_);

            if ($start >= 0 && $end >= 0) {

                push @{$changed_line_ranges{$file}}, [ $start, $end ];

            } elsif (/DO_NOT_COMMIT/) {

                print STDERR "WARNING: file $file contains the string DO_NOT_COMMIT, line $.\n";

            }

        }

    }

    close DIFF;

}

# For each source file, convert line range to function list.

if (%changed_line_ranges) {

    print STDERR "  Extracting affected function names from source files.\n";

    foreach my $file (keys %changed_line_ranges) {

        # Only look for function names in .c files.

        next unless $file =~ /\.(c|cpp|m|mm|h|java)/;

        # Find all the functions in the file.

        open SOURCE, $file or next;

        my @function_ranges = get_function_line_ranges(\*SOURCE, $file);

        close SOURCE;

        # Find all the modified functions.

        my @functions;

        my %saw_function;

        my @change_ranges = (@{$changed_line_ranges{$file}}, []);

        my @change_range = (0, 0);

        FUNCTION: foreach my $function_range_ref (@function_ranges) {

            my @function_range = @$function_range_ref;

            # Advance to successive change ranges.

            for (;; @change_range = @{shift @change_ranges}) {

                last FUNCTION unless @change_range;

                # If past this function, move on to the next one.

                next FUNCTION if $change_range[0] > $function_range[1];

                # If an overlap with this function range, record the function name.

                if ($change_range[1] >= $function_range[0]

                    and $change_range[0] <= $function_range[1]) {

                    if (!$saw_function{$function_range[2]}) {

                        $saw_function{$function_range[2]} = 1;

                        push @functions, $function_range[2];

                    }

                    next FUNCTION;

                }

            }

        }

        # Format the list of functions now.

        if (@functions) {

            $function_lists{$file} = "" if !defined $function_lists{$file};

            $function_lists{$file} .= "\n        (" . join("):\n        (", @functions) . "):";

        }

    }

}

# Get some parameters for the ChangeLog we are about to write.

my $date = changeLogDate($changeLogTimeZone);

my $name = $ENV{CHANGE_LOG_NAME}

  || $ENV{REAL_NAME}

  || gitConfig("user.name")

  || (split /\s*,\s*/, (getpwuid $<)[6])[0]

  || "set REAL_NAME environment variable";

my $email_address = $ENV{CHANGE_LOG_EMAIL_ADDRESS}

  || $ENV{EMAIL_ADDRESS}

  || gitConfig("user.email")

  || "set EMAIL_ADDRESS environment variable";

if ($gitCommit) {

    $name = `$GIT log --max-count=1 --pretty=\"format:%an\" \"$gitCommit\"`;

    $email_address = `$GIT log --max-count=1 --pretty=\"format:%ae\" \"$gitCommit\"`;

}

# Remove trailing parenthesized notes from user name (bit of hack).

$name =~ s/\(.*?\)\s*$//g;

# Find the change logs.

my %has_log;

my %files;

foreach my $file (sort keys %function_lists) {

    my $prefix = $file;

    my $has_log = 0;

    while ($prefix) {

        $prefix =~ s-/[^/]+/?$-/- or $prefix = "";

        $has_log = $has_log{$prefix};

        if (!defined $has_log) {

            $has_log = -f "${prefix}ChangeLog";

            $has_log{$prefix} = $has_log;

        }

        last if $has_log;

    }

    if (!$has_log) {

        print STDERR "No ChangeLog found for $file.\n";

    } else {

        push @{$files{$prefix}}, $file;

    }

}

# Get the latest ChangeLog files from svn.

my $logs = "";

foreach my $prefix (sort keys %files) {

    $logs .= " ${prefix}ChangeLog";

}

if ($logs && $updateChangeLogs && $isSVN) {

    print STDERR "  Running 'svn update' to update ChangeLog files.\n";

    open ERRORS, "$SVN update -q$logs |" or die "The svn update of ChangeLog files failed: $!.\n";

    print STDERR "    $_" while <ERRORS>;

    close ERRORS;

}

# Write out a new ChangeLog file.

foreach my $prefix (sort keys %files) {

    print STDERR "  Editing the ${prefix}ChangeLog file.\n";

    open OLD_CHANGE_LOG, "${prefix}ChangeLog" or die "Could not open ${prefix}ChangeLog file: $!.\n";

    # It's less efficient to read the whole thing into memory than it would be

    # to read it while we prepend to it later, but I like doing this part first.

    my @old_change_log = <OLD_CHANGE_LOG>;

    close OLD_CHANGE_LOG;

    open CHANGE_LOG, "> ${prefix}ChangeLog" or die "Could not write ${prefix}ChangeLog\n.";

    print CHANGE_LOG "$date  $name  <$email_address>\n\n";

    my ($reviewer, $description) = reviewerAndDescriptionForGitCommit($gitCommit) if $gitCommit;

    $reviewer = "NOBODY (OO" . "PS!)" if !$reviewer;

    print CHANGE_LOG "        Reviewed by $reviewer.\n\n";

    print CHANGE_LOG $description . "\n" if $description;

    if ($prefix =~ m/WebCore/ || `pwd` =~ m/WebCore/) {

        if ($didChangeRegressionTests) {

            print CHANGE_LOG testListForChangeLog(sort @addedRegressionTests);

        } else {

            print CHANGE_LOG "        WARNING: NO TEST CASES ADDED OR CHANGED\n\n";

        }

    }

    foreach my $file (sort @{$files{$prefix}}) {

        my $file_stem = substr $file, length $prefix;

        print CHANGE_LOG "        * $file_stem:$function_lists{$file}\n";

    }

    print CHANGE_LOG "\n", @old_change_log;

    close CHANGE_LOG;

}

# Write out another diff.

if ($spewDiff && @changed_files) {

    print STDERR "  Running diff to help you write the ChangeLog entries.\n";

    local $/ = undef; # local slurp mode

    open DIFF, "-|", createPatchCommand($changed_files_string) or die "The diff failed: $!.\n";

    print <DIFF>;

    close DIFF;

}

# Open ChangeLogs.

if ($openChangeLogs && $logs) {

    print STDERR "  Opening the edited ChangeLog files.\n";

    my $editor = $ENV{"CHANGE_LOG_EDIT_APPLICATION"};

    if ($editor) {

        system "open -a '$editor'$logs";

    } else {

        system "open -e$logs";

    }

}

# Done.

exit;

sub canonicalizePath($)

{

    my ($file) = @_;

    # Remove extra slashes and '.' directories in path

    $file = File::Spec->canonpath($file);

    # Remove '..' directories in path

    my @dirs = ();

    foreach my $dir (File::Spec->splitdir($file)) {

        if ($dir eq '..' && $#dirs >= 0 && $dirs[$#dirs] ne '..') {

            pop(@dirs);

        } else {

            push(@dirs, $dir);

        }

    }

    return ($#dirs >= 0) ? File::Spec->catdir(@dirs) : ".";

}

sub changeLogDate($)

{

    my ($timeZone) = @_;

    my $savedTimeZone = $ENV{'TZ'};

    # Set TZ temporarily so that localtime() is in that time zone

    $ENV{'TZ'} = $timeZone;

    my $date = strftime("%Y-%m-%d", localtime());

    if (defined $savedTimeZone) {

         $ENV{'TZ'} = $savedTimeZone;

    } else {

         delete $ENV{'TZ'};

    }

    return $date;

}

sub get_function_line_ranges($$)

{

    my ($file_handle, $file_name) = @_;

    if ($file_name =~ /\.(c|cpp|m|mm|h)$/) {

        return get_function_line_ranges_for_c ($file_handle, $file_name);

    } elsif ($file_name =~ /\.java$/) {

        return get_function_line_ranges_for_java ($file_handle, $file_name);

    }

    return ();

}

sub method_decl_to_selector($)

{

    (my $method_decl) = @_;

    $_ = $method_decl;

    if ((my $comment_stripped) = m-([^/]*)(//|/*).*-) {

        $_ = $comment_stripped;

    }

    s/,\s*...//;

    if (/:/) {

        my @components = split /:/;

        pop @components if (scalar @components > 1);

        $_ = (join ':', map {s/.*[^[:word:]]//; scalar $_;} @components) . ':';

    } else {

        s/\s*$//;

        s/.*[^[:word:]]//;

    }

    return $_;

}

# Read a file and get all the line ranges of the things that look like C functions.

# A function name is the last word before an open parenthesis before the outer

# level open brace. A function starts at the first character after the last close

# brace or semicolon before the function name and ends at the close brace.

# Comment handling is simple-minded but will work for all but pathological cases.

#

# Result is a list of triples: [ start_line, end_line, function_name ].

sub get_function_line_ranges_for_c($$)

{

    my ($file_handle, $file_name) = @_;

    my @ranges;

    my $in_comment = 0;

    my $in_macro = 0;

    my $in_method_declaration = 0;

    my $in_parentheses = 0;

    my $in_braces = 0;

    my $brace_start = 0;

    my $brace_end = 0;

    my $skip_til_brace_or_semicolon = 0;

    my $word = "";

    my $interface_name = "";

    my $potential_method_char = "";

    my $potential_method_spec = "";

    my $potential_start = 0;

    my $potential_name = "";

    my $start = 0;

    my $name = "";

    my $next_word_could_be_namespace = 0;

    my $potential_namespace = "";

    my @namespaces;

    while (<$file_handle>) {

        # Handle continued multi-line comment.

        if ($in_comment) {

            next unless s-.*\*/--;

            $in_comment = 0;

        }

        # Handle continued macro.

        if ($in_macro) {

            $in_macro = 0 unless /\\$/;

            next;

        }

        # Handle start of macro (or any preprocessor directive).

        if (/^\s*\#/) {

            $in_macro = 1 if /^([^\\]|\\.)*\\$/;

            next;

        }

        # Handle comments and quoted text.

        while (m-(/\*|//|\'|\")-) { # \' and \" keep emacs perl mode happy

            my $match = $1;

            if ($match eq "/*") {

                if (!s-/\*.*?\*/--) {

                    s-/\*.*--;

                    $in_comment = 1;

                }

            } elsif ($match eq "//") {

                s-//.*--;

            } else { # ' or "

                if (!s-$match([^\\]|\\.)*?$match--) {

                    warn "mismatched quotes at line $. in $file_name\n";

                    s-$match.*--;

                }

            }

        }

        # continued method declaration

        if ($in_method_declaration) {

              my $original = $_;

              my $method_cont = $_;

              chomp $method_cont;

              $method_cont =~ s/[;\{].*//;

              $potential_method_spec = "${potential_method_spec} ${method_cont}";

              $_ = $original;

              if (/;/) {

                  $potential_start = 0;

                  $potential_method_spec = "";

                  $potential_method_char = "";

                  $in_method_declaration = 0;

                  s/^[^;\{]*//;

              } elsif (/{/) {

                  my $selector = method_decl_to_selector ($potential_method_spec);

                  $potential_name = "${potential_method_char}\[${interface_name} ${selector}\]";

                  $potential_method_spec = "";

                  $potential_method_char = "";

                  $in_method_declaration = 0;

                  $_ = $original;

                  s/^[^;{]*//;

              } elsif (/\@end/) {

                  $in_method_declaration = 0;

                  $interface_name = "";

                  $_ = $original;

              } else {

                  next;

              }

        }

        # start of method declaration

        if ((my $method_char, my $method_spec) = m&^([-+])([^0-9;][^;]*);?$&) {

            my $original = $_;

            if ($interface_name) {

                chomp $method_spec;

                $method_spec =~ s/\{.*//;

                $potential_method_char = $method_char;

                $potential_method_spec = $method_spec;

                $potential_start = $.;