#!/usr/bin/perl
# ------------------------------------------------------------------------------
# NAME
#   fcm
#
# SYNOPSIS
#   fcm SUBCOMMAND [OPTIONS...] ARGS...
#
# DESCRIPTION
#   The fcm command is the frontend of the FCM system. The first argument to the
#   command must be a recognised subcommand. See "fcm help" for a full list of
#   functionalities.
#
# COPYRIGHT
#   (C) Crown copyright Met Office. All rights reserved.
#   For further details please refer to the file COPYRIGHT.txt
#   which you should have received as part of this distribution.
# ------------------------------------------------------------------------------

# Standard pragmas:
use warnings;
use strict;

# Standard modules:
use File::Basename;
use File::Spec;
use Getopt::Long;
use Cwd;

# FCM component modules:
use lib File::Spec->catfile (dirname (dirname ($0)), 'lib');
use Fcm::Config;
use Fcm::Extract;
use Fcm::Build;
use Fcm::Util;

BEGIN {
  eval {
    require Fcm::Cm;
    import Fcm::Cm;

    require Fcm::CmUrl;
    import Fcm::CmUrl;
  }
}

# Function declaration:
sub cmp_ext_cfg;
sub invoke_build_system;
sub invoke_extract_system;
sub invoke_cfg_printer;
sub invoke_cm_system;
sub invoke_www_browser;
sub invoke_help;

# ------------------------------------------------------------------------------

my $prog      = basename $0;
my $year      = (localtime)[5] + 1900;
my $copyright = <<EOF;

(C) Crown copyright $year Met Office. All rights reserved.
EOF

# List of sub-commands recognised by FCM
my %subcommand = (
  HLP => [qw/help ? h/],
  BLD => [qw/build bld/],
  EXT => [qw/extract ext/],
  CFG => [qw/cfg/],
  GUI => [qw/gui/],
  CM  => [qw/
    branch    br
    conflicts cf
    add
    blame     praise annotate ann
    cat
    checkout  co
    cleanup
    commit    ci
    copy      cp
    delete    del    remove   rm
    diff      di
    export
    import
    info
    list      ls
    lock
    log
    merge
    mkdir
    mkpatch
    move      mv     rename   ren
    propdel   pdel   pd
    propedit  pedit  pe
    propget   pget   pg
    proplist  plist  pl
    propset   pset   ps
    resolved
    revert
    status    stat   st
    switch    sw
    unlock
    update    up
  /],
  CMP => [qw/cmp-ext-cfg/],
  WWW => [qw/www trac/],
);

# Get configuration settings
my $config = Fcm::Config->new ();
$config->get_config ();

# Determine the functionality of this invocation of the command
my $function = @ARGV ? shift @ARGV : '';

# Run command accordingly
if (grep {$_ eq $function} @{ $subcommand{BLD} }) {
  invoke_build_system;

} elsif (grep {$_ eq $function} @{ $subcommand{EXT} }) {
  invoke_extract_system;

} elsif (grep {$_ eq $function} @{ $subcommand{CFG} }) {
  invoke_cfg_printer;

} elsif (grep {$_ eq $function} @{ $subcommand{GUI} }) {
  &run_command (['fcm_gui', @ARGV], METHOD => 'exec');

} elsif (grep {$_ eq $function} @{ $subcommand{CM} }) {
  invoke_cm_system;

} elsif (grep {$_ eq $function} @{ $subcommand{CMP} }) {
  cmp_ext_cfg;

} elsif (grep {$_ eq $function} @{ $subcommand{WWW} }) {
  invoke_www_browser;

} elsif ($function =~ /^\s*$/ or grep {$_ eq $function} @{ $subcommand{HLP} }) {
  invoke_help;

} else {
  w_report 'Unknown command: ', $function;
  e_report 'Type "', $prog, ' help" for usage';
}

exit;

# ------------------------------------------------------------------------------
# SYNOPSIS
#   $cfg = &main::cfg ();
#
# DESCRIPTION
#   Return the $config variable.
# ------------------------------------------------------------------------------

sub cfg {
  return $config;
}

# ------------------------------------------------------------------------------
# SYNOPSIS
#   &cmp_ext_cfg ();
#
# DESCRIPTION
#   Compare two similar extract configuration files.
# ------------------------------------------------------------------------------

sub cmp_ext_cfg {
  # Check options
  # ----------------------------------------------------------------------------
  my ($wiki, $verbose);

  GetOptions ('wiki|w=s' => \$wiki, 'verbose|v' => \$verbose);

  # Check arguments
  # ----------------------------------------------------------------------------
  e_report $prog, ' ', $function,
           ': 2 extract config files must be specified, abort.'
    if @ARGV < 2;

  # Invoke 2 new instances of the Fcm::Extract class
  # ----------------------------------------------------------------------------
  my (@cfg, $rc);
  for my $i (0 .. 1) {
    $cfg[$i] = Fcm::Extract->new (CFG_SRC => $ARGV[$i]);

    # Read the extract configuration file
    $rc = $cfg[$i]->decipher_cfg;
    $rc = $cfg[$i]->expand_cfg if $rc;

    last if not $rc;
  }

  # Throw error if command has failed
  # ----------------------------------------------------------------------------
  e_report $prog, ' ', $function,
           ': cannot read extract configuration file, abort' if not $rc;

  # Get list of URLs
  # ----------------------------------------------------------------------------
  my @urls = ();
  for my $i (0 .. 1) {
    # List of branches in each extract configuration file
    my @branches = $cfg[$i]->branches;

    for my $branch (@branches) {
      # Ignore declarations of local directories
      next if $branch->type eq 'user';

      # List of SRC declarations in each branch
      my %dirs = $branch->dirs;

      for my $dir (values %dirs) {
        # Set up a new instance of Fcm::CmUrl object for each SRC declaration
        my $cm_url = Fcm::CmUrl->new (
          URL => $dir . ($branch->version ? '@' . $branch->version : ''),
        );

        $urls[$i]{$cm_url->branch_url}{$dir} = $cm_url;
      }
    }
  }

  # Compare
  # ----------------------------------------------------------------------------
  my %log;
  for my $i (0 .. 1) {
    # Compare the first file with the second one and then vice versa
    my $j = ($i == 0) ? 1 : 0;

    for my $branch (sort keys %{ $urls[$i] }) {
      if (exists $urls[$j]{$branch}) {
        # Same REPOS declarations in both files
        for my $dir (sort keys %{ $urls[$i]{$branch} }) {
          if (exists $urls[$j]{$branch}{$dir}) {
            # Same SRC declarations in both files, only need to compare once
            next if $i == 1;

            my $this_url = $urls[$i]{$branch}{$dir};
            my $that_url = $urls[$j]{$branch}{$dir};

            # Check whether their last changed revisions are the same
            my $this_rev = $this_url->svninfo (FLAG => 'Last Changed Rev');
            my $that_rev = $that_url->svninfo (FLAG => 'Last Changed Rev');

            # Make sure last changed revisions differ
            next if $this_rev eq $that_rev;

            # Not interested in the log before the minimum revision
            my $min_rev = ($this_url->pegrev > $that_url->pegrev)
                          ? $that_url->pegrev : $this_url->pegrev;

            $this_rev = $min_rev if $this_rev < $min_rev;
            $that_rev = $min_rev if $that_rev < $min_rev;

            # Get list of changed revisions using the commit log
            my $u   = ($this_rev > $that_rev) ? $this_url : $that_url;
            my %revs = $u->svnlog (REV => [$this_rev, $that_rev]);

            for my $rev (keys %revs) {
              # Check if revision is already in the list
              next if exists $log{$branch}{$rev};

              # Not interested in the minimum revision
              next if $rev == $min_rev;

              # Get list of changed paths. Accept this revision only if it
              # contains changes in the current branch
              my %paths  = %{ $revs{$rev}{paths} };

              for my $path (keys %paths) {
                my $change_url = Fcm::CmUrl->new (URL => $u->root . $path);

                if ($change_url->branch eq $u->branch) {
                  $log{$branch}{$rev} = $u;
                  last;
                }
              }
            }

          } else {
            # Report SRC declaration in one file but not in another
            print $urls[$i]{$branch}{$dir}->url_peg, ':', "\n";
            print '  in    : ', $ARGV[$i], "\n";
            print '  not in: ', $ARGV[$j], "\n\n";
          }
        }

      } else {
        # Report REPOS declaration in one file but not in another
        print $branch, ':', "\n";
        print '  in    : ', $ARGV[$i], "\n";
        print '  not in: ', $ARGV[$j], "\n\n";
      }
    }
  }

  # Report modifications
  # ----------------------------------------------------------------------------
  print 'Revisions at which declared source directories are modified:', "\n\n"
    if keys %log;

  if (defined $wiki) {
    # Output in wiki format
    my $wiki_url  = Fcm::CmUrl->new (URL => &expand_url_keyword (URL => $wiki));
    my $base_trac = $wiki
                    ? &get_browser_url (URL => $wiki_url->project_url)
                    : $wiki_url;
    $base_trac    = $wiki_url if not $base_trac;

    for my $branch (sort keys %log) {
      # Name of the branch
      my $branch_trac = &get_browser_url (URL => $branch);
      $branch_trac =~ s#^$base_trac(?:/*|$)#source:#;

      print '[', $branch_trac, ']:', "\n";

      # Revision table
      for my $rev (sort {$b <=> $a} keys %{ $log{$branch} }) {
        print $log{$branch}{$rev}->display_svnlog ($rev, $base_trac), "\n";
      }

      print "\n";
    }

  } else {
    my $separator = '-' x 80 . "\n";

    for my $branch (sort keys %log) {
      # Output in plain text format
      print $branch, ':', "\n";

      if ($verbose or &cfg->verbose > 1) {
        # Verbose mode, print revision log
        for my $rev (sort {$b <=> $a} keys %{ $log{$branch} }) {
          print $separator, $log{$branch}{$rev}->display_svnlog ($rev), "\n";
        }

      } else {
        # Normal mode, print list of revisions
        print join (' ', sort {$b <=> $a} keys %{ $log{$branch} }), "\n";
      }

      print $separator, "\n";
    }
  }

  return $rc;
}

# ------------------------------------------------------------------------------
# SYNOPSIS
#   &invoke_build_system ();
#
# DESCRIPTION
#   Invoke the build system.
# ------------------------------------------------------------------------------

sub invoke_build_system {
  my ($archive, $full, $ignore_lock, $jobs, $stage, @targets, $verbose);

  GetOptions (
    'archive|a'   => \$archive,     # switch on archive mode?
    'full|f'      => \$full,        # full build?
    'ignore-lock' => \$ignore_lock, # ignore lock file?
    'jobs|j=i'    => \$jobs,        # number of parallel jobs in make
    'stage|s=s'   => \$stage,       # build up to and including this stage
    'targets|t=s' => \@targets,     # make targets
    'verbose|v=i' => \$verbose,     # verbose level
  );

  # Verbose level
  $config->verbose ($verbose) if defined $verbose;

  # Invoke a new instance of the Fcm::Build class
  my $bld = Fcm::Build->new (CFG_SRC  => @ARGV ? join (' ', @ARGV) : cwd ());

  # Perform build
  $bld->build (
    ARCHIVE     => $archive,
    FULL        => $full,
    IGNORE_LOCK => $ignore_lock,
    JOBS        => $jobs ? $jobs : 1,
    STAGE       => $stage ? $stage : 5,
    TARGETS     => (@targets ? [split (/:/, join (':', @targets))] : [qw/all/]),
  );

  return 1;
}

# ------------------------------------------------------------------------------
# SYNOPSIS
#   &invoke_extract_system ();
#
# DESCRIPTION
#   Invoke the extract system.
# ------------------------------------------------------------------------------

sub invoke_extract_system {
  my ($full, $ignore_lock, $verbose);

  GetOptions (
    'full|f'      => \$full,        # full extract?
    'ignore-lock' => \$ignore_lock, # ignore lock file?
    'verbose|v=i' => \$verbose,     # verbose level
  );

  $config->verbose ($verbose) if defined $verbose;

  # Invoke a new instance of the Fcm::Extract class
  my $ext = Fcm::Extract->new (CFG_SRC => @ARGV ? join (' ', @ARGV) : cwd ());

  # Perform extract
  $ext->extract (FULL => $full, IGNORE_LOCK => $ignore_lock);

  return 1;
}

# ------------------------------------------------------------------------------
# SYNOPSIS
#   &invoke_cfg_printer ();
#
# DESCRIPTION
#   Invoke the CFG file pretty printer.
# ------------------------------------------------------------------------------

sub invoke_cfg_printer {

  use Fcm::CfgFile;

  my $out_file;
  GetOptions (
    'output|o=s'  => \$out_file,  # output file for print
  );

  my $file = join (' ', @ARGV);
  e_report $prog, ' ', $function, ': file not specified, abort.' if ! $file;

  # Invoke a new Fcm::CfgFile instance
  my $cfg = Fcm::CfgFile->new (SRC => $file);

  # Read the cfg file
  my $read = $cfg->read_cfg;
  e_report if not $read;

  # Pretty print CFG file
  $cfg->print_cfg ($out_file);

  return 1;
}

# ------------------------------------------------------------------------------
# SYNOPSIS
#   &invoke_cm_system ();
#
# DESCRIPTION
#   Invoke a code management system command.
# ------------------------------------------------------------------------------

sub invoke_cm_system {

  &cm_command ($function);

  return 1;
}

# ------------------------------------------------------------------------------
# SYNOPSIS
#   &invoke_www_browser ();
#
# DESCRIPTION
#   Invoke a web browser on the specified PATH.
# ------------------------------------------------------------------------------

sub invoke_www_browser {

  # Options
  my ($browser);
  GetOptions (
    'browser|b=s' => \$browser, # browser command
  );

  $browser = &cfg->setting (qw/MISC WEB_BROWSER/) unless $browser;

  # Arguments
  my ($arg) = @ARGV ? $ARGV[0] : (&is_wc () ? '.' : '');
  e_report $prog, ' ', $function,
           ': input URL not specified and . not a working copy, abort.'
    if not $arg;

  # Local PATH?
  $arg = &expand_tilde ($arg);
  $arg = &get_url_of_wc ($arg) if -e $arg;

  # Expand URL and revision keywords
  my $www_url = &expand_url_keyword (URL => $arg);
  my $rev     = 'HEAD';

  if ($www_url =~ m#^(\w+://\S+)@(\S+)$#) {
    $www_url = $1;
    $rev     = $2;
  }

  $rev = &expand_rev_keyword (URL => $www_url, REV => $rev, HEAD => 1)
    unless uc ($rev) eq 'HEAD';

  # Get web browser URL
  $www_url = &get_browser_url (URL => $www_url);
  die 'WWW URL not defined for "', $arg, '", abort' unless $www_url;

  $www_url = $www_url . '?rev=' . $rev;

  # Execute command
  my @command = (split (/\s+/, $browser), $www_url);
  &run_command (\@command, METHOD => 'exec', PRINT => 1);
}

# ------------------------------------------------------------------------------
# SYNOPSIS
#   &invoke_help ();
#
# DESCRIPTION
#   Invoke help.
# ------------------------------------------------------------------------------

sub invoke_help {

  my $cmd = @ARGV ? shift @ARGV : undef;

  if ($cmd) {
    if (grep {$_ eq $cmd} @{ $subcommand{BLD} }) {
      print <<EOF;
$prog $cmd: invoke the build system.
usage: $prog $cmd [OPTIONS...] [CFGFILE]

  The path to a CFG file may be provided. Otherwise, the build system
  searches the default locations for a bld cfg file.

  If no option is specified, the options "-s 5 -t all -j 1 -v 1" are assumed.

  If the option for full build is specified, the sub-directories created by
  previous builds will be removed, so that the current build can start cleanly.

  The -s option can be used to limit the actions performed by the build system
  up to a named stage. The stages are:
    "1", "s" or "setup"                - stage 1, setup
    "2", "pp" or "pre_process"         - stage 2, pre-process
    "3", "gd" or "generate_dependency" - stage 3, generate dependency
    "4", "gi" or "generate_interface"  - stage 4, generate Fortran 9X interface
    "5", "m", "make"                   - stage 5, make

  If a colon separated list of targets is specified using the -t option, the
  default targets specified in the configuration file will not be used.

  If archive mode is switched on, build sub-directories that are only used
  in the build process will be archived to TAR files. The default is off.

  If specified, the verbose level must be an integer greater than 0. Verbose
  level 0 is the quiet mode. Increasing the verbose level will increase the
  amount of diagnostic output.

  When a build is invoked, it sets up a lock file in the build root directory.
  The lock is normally removed at the end of the build. While the lock file is
  in place, othe build commands invoked in the same root directory will fail.
  If you need to bypass this check for whatever reason, you can invoke the
  build system with the --ignore-lock option.

Valid options:
  -a [--archive]     : archive build sub-directories?
  -f [--full]        : full build
  --ignore-lock      : ignore lock files in build root directory
  -j [--jobs] arg    : number of parallel jobs that "make" can handle
  -s [--stage] arg   : perform build up to a named stage
  -t [--targets] arg : build a colon (:) separated list of targets
  -v [--verbose] arg : verbose level
$copyright
EOF

    } elsif (grep {$_ eq $cmd} @{ $subcommand{EXT} }) {
      print <<EOF;
$prog $cmd: invoke the extract system.
usage: $prog $cmd [OPTIONS...] [CFGFILE]

  The path to a CFG file may be provided. Otherwise, the extract system
  searches the default locations for an ext cfg file.

  If no option is specified, the system will attempt an incremental extract
  where appropriate.

  If specified, the verbose level must be an integer greater than 0. Verbose
  level 0 is the quiet mode. Increasing the verbose level will increase the
  amount of diagnostic output.

  When an extract is invoked, it sets up a lock file in the extract destination
  root directory. The lock is normally removed at the end of the extract. While
  the lock file is in place, othe extract commands invoked in the same
  destination root directory will fail. If you need to bypass this check for
  whatever reason, you can invoke the extract system with the --ignore-lock
  option.

Valid options:
  -f [--full]        : perform a full/clean extract
  --ignore-lock      : ignore lock files in build root directory
  -v [--verbose] arg : verbose level
$copyright
EOF

    } elsif (grep {$_ eq $cmd} @{ $subcommand{CFG} }) {
      print <<EOF;
$prog $cmd: invoke the CFG file pretty printer.
usage: $prog $cmd [OPTIONS...] FILE

  If no option is specified, the output will be sent to standard output.

Valid options:
  -o [--output] arg : send output to a file as specified by arg.
$copyright
EOF

    } elsif (grep {$_ eq $cmd} @{ $subcommand{GUI} }) {
      print <<EOF;
$prog $cmd: invoke the GUI wrapper for CM commands.
usage: $prog $cmd DIR

  The optional argument DIR modifies the initial working directory.
$copyright
EOF

    } elsif (grep {$_ eq $cmd} @{ $subcommand{CM} }) {
      @ARGV = qw(--help);
      cm_command ($cmd);

    } elsif (grep {$_ eq $cmd} @{ $subcommand{CMP} }) {
      print <<EOF;
$prog $cmd: compare two similar extract configuration files.
usage: $prog $cmd [OPTIONS...] CFG1 CFG2

  Compares the extract configurations of two similar extract configuration
  files CFG1 and CFG2.

Valid options:
  -v [--verbose]  : print revision tables in verbose mode. In particular,
                    display the change log of each revision.
  -w [--wiki] arg : print revision tables in wiki format. The argument to this
                    option must be the Subversion URL or FCM URL keyword of a
                    FCM project associated with the intended Trac system. This
                    option overrides the -v option.
$copyright
EOF

    } elsif (grep {$_ eq $cmd} @{ $subcommand{WWW} }) {
      print <<EOF;
$prog $cmd: invoke the web repository browser on a Subversion URL.
usage: $prog $cmd [OPTIONS...] [PATH]

  If PATH is specified, it must be a FCM URL keyword, a Subversion URL or the
  PATH to a local working copy. If not specified, the current working directory
  is assumed to be a working copy. If the --browser option is specified, the
  specified web browser command is used to launch the repository browser.
  Otherwise, it attempts to use the default browser from the configuration
  setting.

Valid options:
  -b [--browser] arg : specify a command arg for the web browser.
$copyright
EOF

    } elsif (grep {$_ eq $cmd} @{ $subcommand{HLP} }) {
      print <<EOF;
help (?, h): Describe the usage of $prog or its subcommands.
usage: $prog help [SUBCOMMAND...]
$copyright
EOF

      &run_command ([qw/svn help/, $cmd, @ARGV], PRINT => 1);

    } else {
      warn $prog, ' help: "', $cmd, '" not recognised';
      $cmd = undef;
    }
  }

  if (not $cmd) {
    # Get output from "svn help"
    my @lines = &run_command (
      [qw/svn help/], DEVNULL => 1, METHOD => 'qx', ERROR => 'ignore',
    );

    # Get release number, (and revision number from revision number file)
    my $release  = &cfg->setting ('RELEASE');
    my $rev_file = &cfg->setting ('REV_FILE');

    if (-r $rev_file) {
      open FILE, '<', $rev_file;
      my $rev = readline 'FILE';
      close FILE;

      chomp $rev;
      $release .= '-dev (r' . $rev . ')' if $rev;
    }

    # Print common help
    print <<EOF;
usage: $prog <subcommand> [options] [args]
Flexible configuration management system, release $release.
Type "$prog help <subcommand>" for help on a specific subcommand.

Available subcommands:
  help       (h, ?) - help
  build      (bld)  - build system
EOF

    # The following are only available on platforms with "svn" installed
    if (@lines) {
      print <<EOF;
  branch     (br)   - cm system: branch info & creation
  cfg               - CFG file pretty printer
  cmp-ext-cfg       - compare two similar extract configuration files
  conflicts  (cf)   - cm system: resolve conflicts
  extract    (ext)  - extract system
  mkpatch           - create patches from specified revisions of a URL
  trac       (www)  - cm system: browse a path using the web browser
  <SVN COMMANDS>    - any Subversion sub-commands
EOF
    }

    # Print FCM copyright notice
    print $copyright;

    # Print output from "svn help"
    if (@lines) {
      print "\n";
      &print_command ([qw/svn help/]);
      print @lines;
    }
  }

  return 1;
}

# ------------------------------------------------------------------------------
# SYNOPSIS
#   $ans = &main::get_input (MESSAGE => $mesg, TYPE => $type, DEFAULT => $def);
#
# DESCRIPTION
#   Get an input string from the user and return it as $ans. MESSAGE is the
#   main message printed on screen to prompt the user for an input.  If TYPE is
#   'YN', print message to prompt user to enter either 'y' or 'n'. If TYPE is
#   'YNA', then 'a' is given as a third option. If DEFAULT is set, print message
#   to inform user that the return value will be set to the $def (if nothing is
#   entered).
# ------------------------------------------------------------------------------

sub get_input {
  my %args = @_;
  my $type  = exists $args{TYPE}    ? $args{TYPE}    : '';
  my $mesg  = exists $args{MESSAGE} ? $args{MESSAGE} : '';
  my $def   = exists $args{DEFAULT} ? $args{DEFAULT} : '';

  my $ans;

  while (1) {
    # Print the prompt
    print $mesg;
    print "\n", 'Enter "y" or "n"' if uc ($type) eq 'YN';
    print "\n", 'Enter "y", "n" or "a"' if uc ($type) eq 'YNA';
    print ' (or just press <return> for "', $def, '")' if $def;
    print ': ';

    # Get answer from STDIN
    $ans = <STDIN>;
    chomp $ans;

    # Set answer to default, if necessary
    $ans = $def if ($def and not $ans);

    if ($type =~ /^yna?$/i) {
      # For YN and YNA type dialog boxes,
      # check that the answer is in the correct form
      my $pat = (uc ($type) eq 'YN' ? 'y|n' : 'y|n|a');
      last if $ans =~ /^(?:$pat)/i;

    } else {
      last;
    }
  }

  return $ans;
}

# ------------------------------------------------------------------------------

__END__