#!/usr/bin/perl
# vim:sts=4 sw=4 et
# perltidy -bext=/ -se -i=4 -it=2 -ci=2 -xci -l=132 -pt=2 -ce -cti=1 -cab=4 -cb -cbo=0 -wbb="% + - * / x != == >= <= =~ !~ < > | &" -enc=utf8 -wn -sot -sct -asc -tqw -sbq=0 -csc -csct=30

use strict;
use warnings;
use 5.024;

use Git;

################################################################
# Helper functions
################################################################

my $git = Git->repository;

my $branch_main    = 'refs/heads/main';
my $re_quarterlies = qr{^refs/heads/20\d\dQ\d\z}oms;

{    # sub context to avoid leaking @push_options
    my @push_options;
    for (my $i = 0 ; $i < $ENV{GIT_PUSH_OPTION_COUNT} ; ++$i) {
        push @push_options, $ENV{"GIT_PUSH_OPTION_${i}"};
    }

    sub has_option {
        my ($opt) = @_;
        for (@push_options) {
            return 1 if $opt eq $_;
        }
        return 0;
    } ## end sub has_option
}

my @quarterlies;

for ($git->command('show-ref', '--heads')) {
    my ($hash, $ref) = split / /;
    next if $ref !~ m{refs/heads/\d\d\d\dQ\d\z}oms;
    push @quarterlies, $ref;
}

@quarterlies = sort @quarterlies;

my $latest_quarterly = $quarterlies[-1];

sub do_die {
    die "\n================================================================\n"
      . join("\n", @_)
      . "\n================================================================\n\n";
}

sub short_ref {
    my ($ref) = @_;
    $ref =~ s{\Arefs/heads/}{}oms;
    return $ref;
}

################################################################
# Here starts actual hooks

################################################################
# Some filenames are forbidden in the repo.
sub deny_filenames {
    my (@changed) = @_;

    for my $file (@changed) {
        if (
            $file    =~ m{\A(?:CVS|[.](?:svn|git))\z}oms    # cvs/svn/git
            || $file =~ m{[.](?:rej|orig)\z}oms             # patch
            || $file =~ m{[.]core\z}oms                     # core file
           )
        {
            do_die
              'This file in your commit look suspiciously like core file,',
              'patch leftover, CVS, Subversion or git directory:',
              $file,
              'Please double-check your commit and try committing again.';
        } ## end if ($file =~ m{\A(?:CVS|[.](?:svn|git))\z}oms...)

        if ($file =~ m{(?:\A|/)Makefile.local\z}oms) {
            do_die
              'Makefile.local is a user file and MUST NOT be committed:',
              $file;
        }
    } ## end for my $file (@changed)
} ## end sub deny_filenames

################################################################
# Some filenames are discouraged in the repo.
sub bad_filenames {
    my (@changed) = @_;

    # Gave the magic push option
    return if has_option('allow-bad-filename');

    for my $file (@changed) {
        if ($file =~ m{/py3}oms) {
            do_die                                                                #
              'Adding new py3- ports is forbidden. File:',                        #
              $file,                                                              #
              'The Python ports have flavors and do not need the py3- ports.';    #
        } ## end if ($file =~ m{/py3}oms)

        if ($file =~ m{[:@]}oms) {
            do_die                                                                     #
              'A file in your commit has a colon (:) or (@) in the name:',             #
              $file,                                                                   #
              'which is not allowed. Use _ instead for patches.',                      #
              'Or even better, generate your patches with make makepatch.',            #
              'For further information please read:',                                  #
              'https://docs.freebsd.org/en/books/porters-handbook/slow-patch.html',    #
              'Please fix this and try committing again.';
        } ## end if ($file =~ m{[:@]}oms)
    } ## end for my $file (@changed)
} ## end sub bad_filenames

################################################################
# Empty files forbidden
sub empty {
    my ($rev, @changed) = @_;

    # Gave the magic push option
    return if has_option('allow-empty');

    for my $file (@changed) {
        my $content = $git->command('show', "$rev:$file");

        next if length($content) > 0;

        do_die                                                             #
          "Some files in your commit are empty: $file",                    #
          'Please fix this and try committing again.',                     #
          'If you really need an empty file, ask portmgr for approval',    #
          'and push with --push-option=allow-empty';
    } ## end for my $file (@changed)
} ## end sub empty

################################################################
# vulm.xml has to be committed alone, as it is never merged back to the
# quarterly branches.
sub vuxml_unique {
    my ($ref, @changed) = @_;

    my ($seen, $other) = (0, 0);

    for my $line (@changed) {
        if ($line =~ m{\Asecurity/vuxml/vuln(?:-\d{4})?.xml\z}oms) {
            $seen = 1;
        } else {
            $other = 1;
        }
    } ## end for my $line (@changed)

    if ($seen && $branch_main ne $ref) {
        do_die "Commits to security/vuxml/vuln.xml are only allowed on main";

    }
    if ($seen && $other) {
        do_die "Commit to security/vuxml/vuln.xml first, and then other files";
    }
} ## end sub vuxml_unique

################################################################
# Check git cherry-pick ran with `-x`
sub cherry_pick {
    my ($ref, $log) = @_;

    # Only do this on quarterlies
    return if $ref !~ $re_quarterlies;

    # Gave the magic push option
    return if has_option('direct-quarterly-commit');

    # Found the actual magic words
    return if $log =~ m{
                        ^                                  # Start of line
                        [(]                                # A litteral opening parenthesis
                        cherry[ ]picked[ ]from[ ]commit    # The magic words
                        [0-9a-fA-F]{30,}                   # A commit hash
                        [)]                                # A litteral closing parenthesis
                        $                                  # End of line
                       }omsx;

    do_die                                                                              # Comments
      "$ENV{GL_USER}, you are pushing a commit to ${\(short_ref($ref))} which does",    # to get this
      'not seems to be a cherry-pick.',                                                 # indented
      '',                                                                               # properly
      'If you did a cherry-pick, you probably forgot to add `-x`,',                     # by
      'make sure you do run `git cherry-pick -x <hash>`.',                              # perltidy
      '',                                                                               #
      'If you did a direct commit, make sure it was approved first, and then run:',     #
      "\tgit push --push-option=direct-quarterly-commit";
} ## end sub cherry_pick

################################################################
# Check that commits only go to the latest quarterly branch
sub unsupported_quarterly {
    my ($ref) = @_;

    # Only applies to quarterlies
    return if $ref !~ $re_quarterlies;

    # If we're the latest, great
    return if $ref eq $latest_quarterly;

    # Gave the magic push option
    return if has_option('unsupported-quarterly');

    do_die                                                                                 # Comments
      "$ENV{GL_USER}, you are pushing a commit to ${\(short_ref($ref))} which is not",     # for
      "the latest quarterly branch. The latest is ${\(short_ref($latest_quarterly))}.",    # indentation
      '',                                                                                  #
      'Please check that you really mean to do this, and got approval, use:',              #
      "\tgit push --push-option=unsupported-quarterly";
} ## end sub unsupported_quarterly

################################################################
# Check log does not contains stuff generated by phabricator
sub stomp_bad_formatting {
    my ($log) = @_;

    if ($log =~ m|\n\nReviewers:[\t ]+|oms) {
        do_die "Non-standard/badly formatted template - found 'Reviewers:' instead of 'Reviewed by:'.";
    }

    if ($log =~ m|\n\nSubscribers:[\t ]+|oms) {
        do_die "Non-standard/badly formatted template - found 'Subscribers:'.";
    }
} ## end sub stomp_bad_formatting

################################################################
# Detect merge conflicts
sub detect_merge_conflicts {
    my ($diff) = @_;

    if (
        $diff =~ m{
                   ^           # Beginning of the line
                   [+]         # A literal plus sign, remember, this is a diff
                   (?:
                      <{7}     # <<<<<<<
                      |        # or
                      >{7}     # >>>>>>>
                   )
                   [ ]         # A literal space
                  }omsx
       )
    {
        do_die                                                           #
          'Some parts of your commit look suspiciously like merge',      #
          'conflict markers.  Please double-check your diff and try',    #
          'committing again.';
    } ## end if ($diff =~ m{ ) (})
} ## end sub detect_merge_conflicts

################################################################
# Require newline at end of line
sub detect_no_newline_at_eof {
    my ($diff) = @_;

    if ($diff =~ m{^\\ No newline at end of file$}oms) {
        do_die                                                           #
          "Some files in your commit does not have newline at end",      #
          "of file. Please fix this and try committing again.";
    }
} ## end sub detect_no_newline_at_eof

################################################################
# Check content of some files
sub stage_only {
    my ($rev, @changed) = @_;

    # Gave the magic push option
    return if has_option('allow-bad-staging');

    for my $file (@changed) {
        if ($file =~ m{/Makefile}oms) {
            my $content = $git->command('show', "$rev:$file");

            if ($content =~ m{if.*def.*(NOPORTDOCS|NOPORTEXAMPLES)}oms) {
                do_die                                                         #
                  "Do not commit ports with NOPORTDOCS or NOPORTEXAMPLES.",    #
                  "The port must be converted to proper OPTIONS.  See",        #
                  "http://www.freebsd.org/doc/en_US.ISO8859-1/books/porters-handbook/makefile-options.html";
            } ## end if ($content =~ m{if.*def.*(NOPORTDOCS|NOPORTEXAMPLES)}oms)

            if ($content =~ m{if[^\n]*def[^\n]*NOPORTDATA}oms) {
                do_die                                                         #
                  "Do not commit ports with NOPORTDATA.",                      #
                  "NOPORTDATA is nonsense as a variable affecting all ports.";
            }
        } elsif ($file =~ m{/pkg-plist}oms) {
            my $content = $git->command('show', "$rev:$file");

            if ($content =~ m{%%PORTDATA%%}oms) {
                do_die                                                         #
                  "Do not commit ports with %%PORTDATA%%.",                    #
                  "NOPORTDATA is nonsense as a variable affecting all ports.";
            }

            if ($content =~ m{%%PYTHON_PYOEXTENSION%%}oms) {
                do_die                                                         #
                  "Do not commit ports with %%PYTHON_PYOEXTENSION%%.",         #
                  "Use either pyo for python 2.7 ports or opt-1.pyc for python 3.5+ ports.";
            }
        } elsif ($file =~ m{/distinfo}oms) {
            my $content = $git->command('show', "$rev:$file");

            if ($content !~ m{^TIMESTAMP = [0-9]*$}oms) {
                do_die                                                                 #
                  "Do not commit ports without TIMESTAMP in their distinfo files.",    #
                  "Rerun make makesum to add it.";
            }
        } ## end elsif ($file =~ m{/distinfo}oms)
    } ## end for my $file (@changed)
} ## end sub stage_only

################################################################
# Main loop, everything called in here.
for (<STDIN>) {
    chomp;
    my ($old, $new, $ref) = split / /;

    unsupported_quarterly($ref);

    for my $rev ($git->command('log', '--format=%H', $new, '--not', '--all')) {

        # Get the raw body of the commit
        my $log = $git->command('show', '-s', '--format=%B', $rev);

        # Get the actual diff of the commit
        my $diff = $git->command('show', $rev);

        # Get the changed files, but not the deleted files, we don't need them for the hooks
        my @changed = $git->command('diff', '--name-only', '--diff-filter=d', "$rev~1..$rev");

        deny_filenames(@changed);
        bad_filenames(@changed);
        vuxml_unique($ref, @changed);
        cherry_pick($ref, $log);
        stomp_bad_formatting($log);
        detect_merge_conflicts($diff);
        detect_no_newline_at_eof($diff);
        empty($rev, @changed);
        stage_only($rev, @changed);
    } ## end for my $rev ($git->command('log',...))
} ## end for (<STDIN>)

exit 0;