#!/usr/local/bin/perl -w


use strict;
use warnings;
#################################################################################
#                                                                               #
#   Author: Michael Alessio malessio@perforce.com                               #
#                                                                               #
#   This script is provided as a prototype only and I do not garantee that it   #
#   will work for you.  While feedback and bug reports are apreciated, I do not #
#   garantee that I will address them (but I might :-)                          #
#                                                                               #
#   This script will create a new changelist undoing an existing changelist     #
#   (Possibly requiring multiple resolves depending upon what has happened to   #
#   the involved files since)                                                   #
#                                                                               #
#   Caveat:                                                                     #
#   Delete, Add, and Branch Operations will not be rolled back in this release. #
#   CLI only.  I plan on enabling it to run as a tool in the future.            #
#                                                                               #
#   Usage:                                                                      #
#   1) Run the script and supply it with a changelist number.                   #
#                                                                               #
#################################################################################

my $line;
my $change_output;
my $changelist;
my $i;
my $j;
my $syncstring;
my $integration;
my $filestring;
my $p4string;

my @file_array;
my @revision_array;
my @operation_array;


#
# Get Changelist from user
#

print "Changlist to rollback: ";
$changelist=<STDIN>;
chomp($changelist);
print "\n";

#
# Find file revisions affected by that changelist and how they were affected
#

print "Executing p4 describe -s $changelist\n";
open P4PIPE, "p4 describe -s $changelist |";

$i=0;
while( $line = <P4PIPE> ){
  chomp($line);  
  if ($line eq "Affected files ..."){
    $line = <P4PIPE>;
    while( $line = <P4PIPE> ){
      chomp($line);
      if (($file_array[$i],$revision_array[$i],$operation_array[$i]) = ( $line =~ /^\.\.\.\s(.*)#(\d*) (\w*)$/ )){

        #
        # Notify on add operation
        #
        
        #if (!(($operation_array[$i] eq "edit") or ($operation_array[$i] eq "delete"))){
         # print "File $file_array[$i] was created in change and will remain unaffected\n";
        #}
        $i = $i+1;
      }
    }
  }
}

#
# Sync to appropriate file revisions
#
  
  
$syncstring = "";
$filestring = "Files: \t";
for ($j = 0; $j < $i; $j++){
  if ($operation_array[$j] eq "edit"){  
    $revision_array[$j]=$revision_array[$j]-1;
    $p4string = 'p4 sync "'.$file_array[$j].'#'.$revision_array[$j].'"'."\n";
    print "Executing $p4string\n";
    open P4PIPE, "$p4string |";
    while( $line = <P4PIPE> ){}
    $p4string = 'p4 edit "'.$file_array[$j].'"'."\n";
    print "Executing $p4string\n";
    open P4PIPE, "$p4string |";
    while( $line = <P4PIPE> ){}
    $filestring = "$filestring \n\t$file_array[$j]";
  }
  elsif ($operation_array[$j] eq "integrate"){
    $revision_array[$j]=$revision_array[$j]-1;
    $p4string = 'p4 sync "'.$file_array[$j].'#'.$revision_array[$j].'"'."\n";
    print "Executing $p4string\n";
    open P4PIPE, "$p4string |";
    while( $line = <P4PIPE> ){}
    $p4string = 'p4 edit "'.$file_array[$j].'"'."\n";
    print "Executing $p4string\n";
    open P4PIPE, "$p4string |";
    while( $line = <P4PIPE> ){}
    $filestring = "Hello\t".$filestring.$file_array[$j]."\n";
  }
#  elsif ($operation_array[$j] eq "delete"){
#    $revision_array[$j]=$revision_array[$j]-1;
#    $p4string = 'p4 sync "'.$file_array[$j].'#'.$revision_array[$j].'"'."\n";
#    print "Executing $p4string\n";
#    open P4PIPE, "$p4string |";
#    while( $line = <P4PIPE> ){}
#    $p4string = 'p4 edit "'.$file_array[$j].'"'."\n";
#    print "Executing $p4string\n";
#    open P4PIPE, "$p4string |";
#    while( $line = <P4PIPE> ){}
#    $filestring = "\t".$filestring.$file_array[$j]."\n";
#  } 
#  elsif ($operation_array[$j] eq "add"){
#    $p4string = 'p4 delete "'.$file_array[$j].'"'."\n";
#    print "Executing $p4string\n";
#    open P4PIPE, "$p4string |";
#    while( $line = <P4PIPE> ){}
#    $filestring = "\t".$filestring.$file_array[$j]."\n";
#  }   
#  elsif ($operation_array[$j] eq "branch"){
#    $p4string = 'p4 delete "'.$file_array[$j].'"'."\n";
#    print "Executing $p4string\n";
#    open P4PIPE, "$p4string |";
#    while( $line = <P4PIPE> ){}
#    $filestring = "\t".$filestring.$file_array[$j]."\n";
#  }
   else{
     print "$operation_array[$j] not supported in rollback\n";
   }
}

  #
  # create a new changelist
  #
  
  print "p4 change -i\n";
  print "Change:	new\n";
  print "Description: Rollback of changelist $changelist\n";
  print $filestring;



  open P4PIPE, "| p4 change -i";
  print P4PIPE "Change:	new\n";
  print P4PIPE "Description: Rollback of changelist $changelist\n";
  print P4PIPE $filestring;
  close P4PIPE;