#!/usr/bin/perl -w

# Simple script to apply a whole bunch of patches to Freeciv.
# Usage:
# apply.pl [-p patch]
#      apply all patches in order to the current directory
#      (should be run within the freeciv-patched directory)
#      If the -p option is specified, only patches up to (but not including)
#      the named patch are applied
# apply.pl -R [-p patch]
#      remove all patches (in reverse order) from the current directory
# apply.pl -f
#      recreate all patches; requires "makefreepatch.sh" in $toppath.

use Getopt::Std;

# The directory where you keep all your Freeciv CVS builds
$toppath = "/scratch/ben/freeciv";

# The directory where the impr-gen patches are stored
$patchpath = "$toppath/impr-gen-patches";

# Clean Freeciv CVS
$origpath = "$toppath/freeciv-cvs";

# Freeciv CVS + impr-gen patches
$newpath = "$toppath/freeciv-patched";

# Directory where the -f option puts new, recreated patches
$newpatchpath = "$patchpath/new";

$errors = 0;

# The patches to apply, in order
@patches = (
  "neweff-implement-update-v11.patch",
  "neweff-iterator-v6.patch",
  "numbuildings-v2.patch",
  "effect-update-defer-v10.patch",
  "effect-city-bonuses-v14.patch",
  "effect-citydlg-happiness-v4.patch",
  "effect-tile-bonuses-v10.patch",
  "effect-unit-mods-v11.patch",
  "effect-boost-research-v12.patch",
  "effect-corrupt-revolt-v5.patch",
  "effect-upgrades-v11.patch",
  "effect-global-city-v41.patch",
  "effect-combat-v7.patch",
  "effect-govchange-v4.patch",
  "impr-gen-readme-v7.patch",
  "effect-no-sink-deep-v3.patch",
  "effect-spy-resistant-v3.patch",
  "helpdata-v4.patch",
  "effect-palace-walls-v9.patch",
  "destroyed-effects-v20.patch",
  "effect-unit-v20.patch",
  "effect-nationgov-v11.patch",
  "effect-outside-v10.patch",
  "effect-cost-v2.patch"
);

my (%opts, $lastpatch);

getopts('Rfp:', \%opts);

$lastpatch = $#patches + 1;
if (defined($opts{p})) {
  for ($i = 0; $i <= $#patches; $i++) {
    if ($patches[$i] =~ /^$opts{p}/) {
      $lastpatch = $i;
      last;
    }
  }
}

if (defined($opts{R})) {
  for ($i = $lastpatch - 1; $i >= 0; $i--) {
    print "### Removing $patches[$i]\n";
    system("patch -p1 -R < $patchpath/$patches[$i]");
    if ($? >> 8) {
      $errors++;
    }
  }
  if ($lastpatch <= $#patches) {
    print "\nPatches removed up to (but not including) ".
          "$patches[$lastpatch]\n\n";
  }
} elsif (defined($opts{f})) {
  chdir($newpath);
  for ($i = 0; $i < $lastpatch; $i++) {
    print "### Fixing up $patches[$i]\n";
    chdir($newpath);
    print "### Applying $patches[$i] to freeciv-patched\n";
    system("patch -p1 < $patchpath/$patches[$i]");
    if ($? >> 8) {
      $errors++;
    }
    chdir($toppath);
    print "### Generating new $patches[$i]\n";
    system("./makefreecivpatch.sh > $newpatchpath/$patches[$i]");
    chdir($origpath);
    print "### Applying $patches[$i] to freeciv-cvs\n";
    system("patch -p1 < $patchpath/$patches[$i]");
    if ($? >> 8) {
      $errors++;
    }
  }
  chdir($origpath);
  for ($i = $lastpatch - 1; $i >= 0; $i--) {
    print "### Removing $patches[$i] from freeciv-cvs\n";
    system("patch -p1 -R < $patchpath/$patches[$i]");
    if ($? >> 8) {
      $errors++;
    }
  }
} else {
  for ($i = 0; $i < $lastpatch; $i++) {
    print "### Applying $patches[$i]\n";
    system("patch -p1 < $patchpath/$patches[$i]");
    if ($? >> 8) {
      $errors++;
    }
  }
  if ($lastpatch <= $#patches) {
    print "\nPatches added up to (but not including) ".
          "$patches[$lastpatch]\n\n";
  }
}

if ($errors > 0) {
  print "\n\nWARNING: $errors errors were encountered while applying ".
        "patches - check output!\n\n";
}