#!/usr/bin/perl -w

use strict;

# Usage:
#
# ./darcs-all [-q] [-s] [-i] [-r repo]
#             [--nofib] [--testsuite] [--checked-out] cmd [darcs flags]
#
# Applies the darcs command "cmd" to each repository in the tree.
#
# e.g.
#      ./darcs-all -r http://darcs.haskell.org/ghc get
#          To get any repos which do not exist in the local tree
#
#      ./darcs-all -r ~/ghc-validate push
#          To push all your repos to the ~/ghc-validate tree
#
#      ./darcs-all pull -a
#          To pull everything from the default repos
#
#      ./darc-all push --dry-run
#          To see what local patches you have relative to the main repos
#
# -------------- Flags -------------------
#   -q says to be quite, and -s to be silent.
#
#   -i says to ignore darcs errors and move on to the next repository
#
#   -r repo says to use repo as the location of package repositories
#
#   --checked-out says that the remote repo is in checked-out layout, as
#   opposed to the layout used for the main repo.  By default a repo on
#   the local filesystem is assumed to be checked-out, and repos accessed
#   via HTTP or SSH are assumed to be in the main repo layout; use
#   --checked-out to override the latter.
#
#   --nofib, --testsuite also get the nofib and testsuite repos respectively
#
#   The darcs get flag you are most likely to want is --complete. By
#   default we pass darcs the --partial flag.
#
# ------------ Which repos to use -------------
# darcs-all uses the following algorithm to decide which remote repos to use
#
#  It always computes the remote repos from a single base, $repo_base
#  How is $repo_base set?  
#    If you say "-r repo", then that's $repo_base
#    othewise $repo_base is set thus:
#       look in _darcs/prefs/defaultrepo, 
#       and remove the trailing 'ghc'
#
#  Then darcs-all iterates over the package found in the file
#  ./packages, which has entries like:
#         libraries/array  packages/array  darcs
#    or, in general
#         <local-path>  <remote-path> <vcs>
# 
#    If $repo_base looks like a local filesystem path, or if you give
#    the --checked-out flag, darcs-all works on repos of form
#          $repo_base/<local-path>
#    otherwise darcs-all works on repos of form
#          $repo_base/<remote-path>
#    This logic lets you say
#      both    darcs-all -r http://darcs.haskell.org/ghc-6.12 pull
#      and     darcs-all -r ../HEAD pull
#    The latter is called a "checked-out tree".

# NB: darcs-all *ignores* the defaultrepo of all repos other than the
# root one.  So the remote repos must be laid out in one of the two
# formats given by <local-path> and <remote-path> in the file 'packages'.


$| = 1; # autoflush stdout after each print, to avoid output after die

my $defaultrepo;

my $verbose = 2;
my $ignore_failure = 0;
my $want_remote_repo = 0;
my $checked_out_flag = 0;

my %tags;

my @packages;

# Figure out where to get the other repositories from.
sub getrepo {
    my $basedir = ".";
    my $repo = $defaultrepo || `cat $basedir/_darcs/prefs/defaultrepo`;
    chomp $repo;

    my $repo_base;
    my $checked_out_tree;

    if ($repo =~ /^...*:/) {
        # HTTP or SSH
        # Above regex says "at least two chars before the :", to avoid
        # catching Win32 drives ("C:\").
        $repo_base = $repo;

        # --checked-out is needed if you want to use a checked-out repo
        # over SSH or HTTP
        if ($checked_out_flag) {
            $checked_out_tree = 1;
        } else {
            $checked_out_tree = 0;
        }

        # Don't drop the last part of the path if specified with -r, as
        # it expects repos of the form:
        #
        #   http://darcs.haskell.org
        #
        # rather than
        #   
        #   http://darcs.haskell.org/ghc
        #
        if (!$defaultrepo) {
            $repo_base =~ s#/[^/]+/?$##;
        }
    }
    elsif ($repo =~ /^\/|\.\.\/|.:(\/|\\)/) {
        # Local filesystem, either absolute or relative path
        # (assumes a checked-out tree):
        $repo_base = $repo;
        $checked_out_tree = 1;
    }
    else {
        die "Couldn't work out repo";
    }

    return $repo_base, $checked_out_tree;
}

sub message {
    if ($verbose >= 2) {
        print "@_\n";
    }
}

sub warning {
    if ($verbose >= 1) {
        print "warning: @_\n";
    }
}

sub darcs {
    message "== running darcs @_";
    system ("darcs", @_) == 0
       or $ignore_failure
       or die "darcs failed: $?";
}

sub parsePackages {
    my @repos;
    my $lineNum;

    my ($repo_base, $checked_out_tree) = getrepo();

    open IN, "< packages" or die "Can't open packages file";
    @repos = <IN>;
    close IN;

    @packages = ();
    $lineNum = 0;
    foreach (@repos) {
        chomp;
        $lineNum++;
        if (/^([^# ]+) +([^ ]+) +([^ ]+) +([^ ]+) +([^ ]+)$/) {
            my %line;
            $line{"localpath"}  = $1;
            $line{"tag"}        = $2;
            $line{"remotepath"} = $3;
            $line{"vcs"}        = $4;
            $line{"upstream"}   = $5;
            push @packages, \%line;
        }
        elsif (! /^(#.*)?$/) {
            die "Bad content on line $lineNum of packages file: $_";
        }
    }
}

sub darcsall {
    my $localpath;
    my $remotepath;
    my $path;
    my $tag;
    my @repos;
    my $command = $_[0];
    my $line;

    my ($repo_base, $checked_out_tree) = getrepo();

    for $line (@packages) {
        $localpath  = $$line{"localpath"};
        $tag        = $$line{"tag"};
        $remotepath = $$line{"remotepath"};

        if ($checked_out_tree) {
            $path = "$repo_base/$localpath";
        }
        else {
            $path = "$repo_base/$remotepath";
        }

        if (-d "$localpath/_darcs") {
            if ($want_remote_repo) {
                if ($command =~ /^opt/) {
                    # Allows ./darcs-all optimize --relink
                    darcs (@_, "--repodir", $localpath, "--sibling=$path");
                } else {
                    darcs (@_, "--repodir", $localpath, $path);
                }
            } else {
                darcs (@_, "--repodir", $localpath);
            }
        }
        elsif ($tag eq "-") {
            message "== Required repo $localpath is missing! Skipping";
        }
        else {
            message "== $localpath repo not present; skipping";
        }
    }
}

sub darcsget {
    my $r_flags;
    my $localpath;
    my $remotepath;
    my $path;
    my $tag;
    my @repos;
    my $line;

    my ($repo_base, $checked_out_tree) = getrepo();

    if (! grep /(?:--complete|--partial|--lazy)/, @_) {
        warning("adding --partial, to override use --complete");
        $r_flags = [@_, "--partial"];
    }
    else {
        $r_flags = \@_;
    }

    for $line (@packages) {
        $localpath  = $$line{"localpath"};
        $tag        = $$line{"tag"};
        $remotepath = $$line{"remotepath"};

        if ($checked_out_tree) {
            $path = "$repo_base/$localpath";
        }
        else {
            $path = "$repo_base/$remotepath";
        }

        if ($tags{$tag} eq 1) {
            if (-d $localpath) {
                warning("$localpath already present; omitting");
            }
            else {
                darcs (@$r_flags, $path, $localpath);
            }
        }
    }
}

sub darcsupstreampull {
    my $localpath;
    my $upstream;
    my $line;

    for $line (@packages) {
        $localpath  = $$line{"localpath"};
        $upstream   = $$line{"upstream"};

        if ($upstream ne "-") {
            if (-d $localpath) {
                darcs ("pull", @_, "--repodir", $localpath, $upstream);
            }
        }
    }
}

sub main {
    if (! -d "compiler") {
        die "error: darcs-all must be run from the top level of the ghc tree."
    }

    $tags{"-"} = 1;
    $tags{"dph"} = 1;
    $tags{"nofib"} = 0;
    $tags{"testsuite"} = 0;
    $tags{"extra"} = 0;

    while ($#_ ne -1) {
        my $arg = shift;
        # We handle -q here as well as lower down as we need to skip over it
        # if it comes before the darcs command
        if ($arg eq "-q") {
            $verbose = 1;
        }
        elsif ($arg eq "-s") {
            $verbose = 0;
        }
        elsif ($arg eq "-r") {
            $defaultrepo = shift;
        }
        elsif ($arg eq "-i") {
            $ignore_failure = 1;
        }
        # --nofib tells get to also grab the nofib repo.
        # It has no effect on the other commands.
        elsif ($arg eq "--nofib") {
            $tags{"nofib"} = 1;
        }
        elsif ($arg eq "--no-nofib") {
            $tags{"nofib"} = 0;
        }
        # --testsuite tells get to also grab the testsuite repo.
        # It has no effect on the other commands.
        elsif ($arg eq "--testsuite") {
            $tags{"testsuite"} = 1;
        }
        elsif ($arg eq "--no-testsuite") {
            $tags{"testsuite"} = 0;
        }
        # --dph tells get to also grab the dph repo.
        # It has no effect on the other commands.
        elsif ($arg eq "--dph") {
            $tags{"dph"} = 1;
        }
        elsif ($arg eq "--no-dph") {
            $tags{"dph"} = 0;
        }
        # --extralibs tells get to also grab the extra repos.
        # It has no effect on the other commands.
        elsif ($arg eq "--extra") {
            $tags{"extra"} = 1;
        }
        elsif ($arg eq "--no-extra") {
            $tags{"extra"} = 0;
        }
        # Use --checked-out if the remote repos are a checked-out tree,
        # rather than the master trees.
        elsif ($arg eq "--checked-out") {
            $checked_out_flag = 1;
        }
        else {
            unshift @_, $arg;
            if (grep /^-q$/, @_) {
                $verbose = 1;
            }
            last;
        }
    }

    if ($#_ eq -1) {
        die "What do you want to do?";
    }
    my $command = $_[0];
    parsePackages;
    if ($command eq "get") {
        darcsget @_;
    }
    elsif ($command eq "upstreampull") {
        shift;
        darcsupstreampull @_;
    }
    else {
        if ($command =~ /^(?:w|wh|wha|what|whats|whatsn|whatsne|whatsnew)$/) {
            # Hack around whatsnew failing if there are no changes
            $ignore_failure = 1;
        }
        if ($command =~ /^(pul|pus|sen|put|opt)/) {
            $want_remote_repo = 1;
        }
        darcsall @_;
    }
}

END {
    my $ec = $?;

    message "== Checking for old bytestring repo";
    if (-d "libraries/bytestring/_darcs") {
        if ((system "darcs annotate --repodir libraries/bytestring --match 'hash 20080118173113-3fd76-d5b74c04372a297b585ebea4e16d524551ce5035' > /dev/null 2> /dev/null") == 0) {
            print <<EOF;
============================
ATTENTION!

You have an old bytestring repository in your GHC tree!

Please remove it (e.g. "rm -r libraries/bytestring"), and the new
version of bytestring will be used from a tarball instead.
============================
EOF
        }
    }

    message "== Checking for bytestring tarball";
    if (-d "libraries/bytestring" && not -d "libraries/bytestring/_darcs") {
        print <<EOF;
============================
ATTENTION!

You have an old bytestring in your GHC tree!

Please remove it (e.g. "rm -r libraries/bytestring"), and then run
"./darcs-all get" to get the darcs repository.
============================
EOF
    }

    message "== Checking for unpulled tarball patches";
    if ((system "darcs annotate --match 'hash 20090930200358-3fd76-cab3bf4a0a9e3902eb6dd41f71712ad3a6a9bcd1' > /dev/null 2> /dev/null") == 0) {
        print <<EOF;
============================
ATTENTION!

You have the unpulled tarball patches in your GHC tree!

Please remove them:
    darcs unpull -p "Use mingw tarballs to get mingw on Windows"
and say yes to each patch.
============================
EOF
    }

    $? = $ec;
}

main(@ARGV);