#!/bin/perl

# perl script to integrate changes

use Getopt::Std;
use vars qw'$opt_h $opt_c $opt_p $opt_t $opt_s';

getopts('hc:s:t:p:') || usage();
if ($opt_h || (!$opt_c || !$opt_t || !$opt_s)) { usage(); }

$opt_p ||= "p4";
my ($p4) = $opt_p;
my ($change) = $opt_c;

# intelligently decipher $opt_t and $opt_s
my ($valid_s) = 0;
my ($valid_t) = 0;
# removing trailing dots
$opt_t =~ s/\.\.\.$//;
$opt_s =~ s/\.\.\.$//;
# remove trailing slash
$opt_t =~ s/\/$//;
$opt_s =~ s/\/$//;
# check for perforce path
if ($opt_t =~ /^\/\//) {
   my ($dirs) = `p4 dirs $opt_t 2>&1`;
   if ($dirs =~ /no such files/) {
      die "$opt_t doesn't seem to exist?\n";
   } else {
      $valid_t = 1;
   }
}
if ($opt_s =~ /^\/\//) {
   my ($dirs) = `p4 dirs $opt_s 2>&1`;
   if ($dirs =~ /no such files/) {
      die "$opt_s doesn't seem to exist?\n";
   } else {
      $valid_s = 1;
   }
}
if ($ENV{MAHI_SW_BASE}) {
   $ENV{MAHI_SW_BASE} =~ s/\\/\//g; # unix-style slashes
   if (-d "$ENV{MAHI_SW_BASE}/$opt_t") {
      $opt_t = "$ENV{MAHI_SW_BASE}/$opt_t";
      $valid_t = 1;
   }
   if (-d "$ENV{MAHI_SW_BASE}/$opt_s") {
      $opt_s = "$ENV{MAHI_SW_BASE}/$opt_s";
      $valid_s = 1;
   }
}
if (-d "$opt_t") {
   $valid_t = 1;
}
if (-d "$opt_s") {
   $valid_s = 1;
}

unless ($valid_t && $valid_s) {
   die "$opt_s or $opt_t is invalid.\n";
}
$opt_s =~ s/$/\/\.\.\./;
$opt_t =~ s/$/\/\.\.\./;

my (@change) = `$p4 describe -s $change`;
my (@decription);

foreach my $line (@change) {
   last if ($line =~ /Affected files \.\.\./);
   chomp ($line);
   $line =~ s/^[ \t]+//;
   push (@description, $line);
}

# create a change
open (P4CHANGE, ">p4change.tmp") || die "cannot open p4change.tmp\n";
print P4CHANGE "Change:\t new\n";
print P4CHANGE "Description:\n\tIntegrated the following from $opt_s:\n";
foreach (@description) {
   print P4CHANGE "\t$_\n";
}
close (P4CHANGE);
my ($newchange) = `$p4 change -i < p4change.tmp`;
unlink (p4change.tmp);
if ($newchange =~ /Change (\d+) created./) {
   $newchange = $1;
} else {
   die "could not create change\n";
}

my (@integ) = `$p4 integrate -c $newchange $opt_s\@$change,$change $opt_t`;
if ($#integ < 0) {
   `$p4 change -d $newchange`;
   die "Could not integrate using the following cmd:\n$p4 integrate -c $newchange $opt_s\@$change,$change $opt_t\nEnsure that source and target params are correct, that change $change is the correct changelist and the these changes haven't all ready been integrated.\n";
} 
foreach my $file (@integ) {
   if ($file =~ /(\/\/.*)#\d+ - /) {
      $file = $1;
   } else {
      die "parsing error...\n";
   }
   my ($resolve) = `$p4 resolve -as $file`;
}

sub usage {
   # print usage
   print "NAME\n$0\n";
   print "SYNOPSIS\n$0 [-h] [-c <changelist number> -s <source branch> -t <target branch>] \n";
   print "DESCRIPTION\nA perl script to integrate a single changelist.\n";
   print "OPTIONS\n";
   print "\t-c\n\t\tchangelist number.\n";
   print "\t-p\n\t\tperforce executable (default 'p4').\n";
   print "\t-s\n\t\tsource branch\n";
   print "\t-t\n\t\ttarget branch\n";
   print "\n";
   exit (1);
}