#!/usr/bin/perl

# Copyright (C) 2007 Eric L. Wilhelm

use warnings;
use strict;

=head1 NAME

dev_fetch_books - emulate svn:externals, sans annoying bits

=head1 Synopsis

The svn:externals functionality would be great if it could somehow not
be consistently slow and noisy.  This reinvention means you have to
manually update it, but means you get to manually update it.

=cut

package bin::dev_fetch_books;

use File::Basename ();
use YAML::Syck ();

`which svn` or die "you have no svn";
# no point is using what which said if it only causes problems.
my $svn = 'svn';

my $start_url = 'http://svn.dotreader.com/svn/dotreader/trunk/books';
my $book_dir = 'books/';

sub main {
  my (@args) = @_;

  unless(-e $book_dir) {
    print "checkout to $book_dir\n";
    system($svn, 'checkout', $start_url) and die "oops $?";
  }

  # otherwise, go into update mode

  my $defs = YAML::Syck::LoadFile($book_dir . 'externals.yml');
  ref($defs) or die "something wrong";

  foreach my $dir (keys(%$defs)) {
    local $| = 1;
    print "$dir ... ";
    my $dest_dir = $book_dir.$dir;
    # TODO we could probably cut this time to 1/n by remembering the
    # current HEAD rev for a given repository.
    if(-e $dest_dir) {
      system($svn, 'update', $dest_dir) and die "update $dir failed";
    }
    else {
      system($svn, 'checkout', $defs->{$dir}, $dest_dir) and
        die "checkout $dir failed";
    }
  }

}

package main;

if($0 eq __FILE__) {
  bin::dev_fetch_books::main(@ARGV);
}

# vi:ts=2:sw=2:et:sta
my $package = 'bin::dev_fetch_books';